Hurricane evacuation decision making guide Sumter County

[From the U.S. Government Printing Office, www.gpo.gov]

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HURRICANE EVACUATION

DECISION MAKING GUIDE:

SUMTER COUNTY

Prepared by the

Withlacoochee Regional Planning Council

July, 1984

The preparation of this report was primarily supported
by a grant from the U. S. Office of Coastal Management,
National Oceanic and Atmospheric Administration; and
the Florida Office of Coastal Management, Department
of Environmental Regulation through the Coastal Zone
Management Act of 1972, as amended. Supplemental
funding was provided by the Florida Department of
Community Affairs.

WITHLACOOCHEE REGIONAL PLANNING COUNCIL

BOARD OF DIRECTORS

Citrus County

Wilbur H. Langley, Sr.
N.R."Nick" Bryant
**S.H. "Sid" Kennedy*
***Charles A. Black

Hernando County

*Frank Fish, Secretary
***Ralph Shepard
**Charles P. Fagan
Henry D. Ledbetter

Levy County

**W.S. "Sammy" Cason
J-L. Townsend
***Kathryn P. Harris, Chairwoman*

Marion County

Roy Abshier
Bruce Bartlett
**Marianthe Coppedge
***Robert A. Schwalb, Jr.
***Nicholas Mansito, Jr.
***Eugene A. Poole, Vice-Chrm.

City of Ocala

*Sally Ann Knope**

Sumter County

**G.H. Tompkins
*W. Tom Blackmon
***Eunice M. Neville

*Executive Committee
"Municipal Representative
***Governor Appointees

TABLE OF CONTENTS

CHAPTER PAGE

INTRODUCTION . . . . . . . . . . . . . . . . . . 1

I QUICK RE FERENCE GUIDE . . . . . . . . . . . . . 2

Ii EXTENT OF EVACUATION . . . . . . . . . . . . . . 5

III PUBLIC SHELTER CAPACITY . . . . . . . . . . . . 13

IV EVACUATION TIMES . . . . . . . . . . . . . . . . 16

V WARNING INFORMATION . . . . . . . . . . . . . . 25

Vi REGIONAL COORDINATIVE MECHANISM . . . . . . . . 28

VII LOCAL COORDINATION . . . . . . . . . . . . . . . 36

APPENDIX A - SUMTER COUNTY EVACUATION ZONE
BOUNDARIES . . . . . . . . . . . . . . . . . . A-1

APPENDIX B - THE SAFFIR/SIMPSON HURRICANE
SCALE . . . . . . . . . . . . . . . . . . . .

LIST OF MAPS

MAP PAGE

1 EVACUATION NETWORK-SUMTER COUNTY . . . . . . . . . 9

2 EVACUATION ZONES-SUMTER COUNTY . . . . . . . . . . 10

LIST OF TABLES

TABLE PAGE

1 SUMTER COUNTY EVACUATION TIMES . . . . . . . . . . 3

2 SUMTER COUNTY EVACUATION TIMES . . . . . . . . . . 4

3 INLAND SHELTER CAPACITY SUMMARY . . . . . . . . . 11

4 SUMTER COUNTY EVACUATING POPULATION AT RISK AND
EVACUATING VEHICLES . . . . . . . . . . . . . . 12

5 SUMTER COUNTY PRIMARY SHELTERS . . . . . . . . . . 14

6 SUMTER COUNTY ALTERNATE SHELTERS . . . . . . . . . 15

7 GALE FORCE WIND ANALYSIS AND SHELTER DURATION
PERIOD BY STORM TYPE AND INTENSITY . . . . . . . 17

8 SENSITIVITY ANALYSIS OF PRE-LANDFALL HAZARD
TIMES . . . . . . . . . . . . . . . . . . . . . 20

9 REGIONAL VULNERABILITY LEVELS . . . . . . . . . . 22

10 EVACUATION TIMES VULNERABILITY LEVEL 'A'. . . 23

11 EVACUATION TIMES VULNERABILITY LEVEL 'B'. . . 24

LIST OF FIGURES

FIGURE PAGE

1 EMERGENCY FACILITY PROFILE . . . . . . . . . . . . 31

INTRODUCTION

As part of the Withlacoochee Hurricane Evacuation Plan,
decision-making guides are to be furnished to each county
in the region and the Florida Bureau of Emergency Management
for use as a ready reference tool by decision-makers during
the approach of the storm. The purpose of the guide is to
provide information to assist local and state civil.defense
officials and other emergency management organizations to
implement the critical actions necessary to prepare for, and
respond to, a hurricane threat.

This guide consist of two parts. The first part is
excerpted from the technical data report prepared for the
inland counties of the region. This section provides infor-
mation on the expected number of evacuees, needed sheltering
and evacuation times according to the direction of the
hurricane.

The second part is concerned with the coordination of
the evacuation. This includes information on the roles and
responsibilities of agencies involved in the issuance of the
evacuation order and the management of the evacuation. In
addition, the coordination section includes a discussion of
the implications of the findings of the technical data report
on local evacuation decision-making.

Also, a quick reference guide is included which presents
information on the expected number of evacuees and recommended
evacuation order times according to several evacuation
scenarios.

CHAPTER I

QUICK REFERENCE GUIDE

The purpose of this chapter is to provide local decision-
makers with a quick reference guide as to the number of
persons vulnerable to hurricane hazards in Sumter County and
the recommended evacuation order times according to the
forecasted intensity of the hurricane.

As stated in the technical report, it is recommended
that mobile home residents be evacuated due to hazards
created by hurricane winds. An estimated 4,902 persons from
Sumter County are expected to seek public shelter.

It should be noted that the remaining chapters in this
document should be read prior to consulting this quick
reference guide in order to gain familiarity with how these
numbers were calculated.

The evacuation times shown in the following tables
include the hours needed for clearance and avoidance of the
pre-landfall wind hazard.

TABLE 1

SUMTER COUNTY
EVACUATION TIMES
LOCAL EVACUATION ONLY

STORM TRACK INTENSITY EVACUATION,TIMES (Hours)

Normal 1 12 3/4
Normal 2 13 1/4
Normal 3 15 1/4
Normal 4 16 1/4
Normal 5 14 1/4
-----------------------------------------------------------------------
Exiting 1 11 3/4
Exiting 2 12 3/4

-----------
Paralleling 1 11 3/4
Paralleling 2 12 3/4
Paralleling 3 14 1/4
Paralleling 4 15 1/4

TABLE 2

SUMTER COUNTY EVACUATION TIMES
(With Tampa Bay Area Evacuation)

STORM TRACK1/ INTENSITY EVACUATION TIME (Hours)-

Normal 1 25
Normal 2 25 1/2
Normal 3 27 1/2
Normal 4 28 1/2
Normal 5 26 1/2

----------------------------------------------------------------------
Exiting 1 24
Exiting 2 25
P_a__ra_1__1e__7 -------------------------------------------------------------
ling 1 24
Paralleling 2 25
Paralleling 3 26 1/2
Paralleling 4 27 1/2

1/ A normal storm track is a head-on direct strike.

CHAPTER II

EXTENT OF EVACUATION

The extent of the hurricane evacuation refers to the
identification of those persons vulnerable to hurricane
hazards in Sumter County and the calculation of this vulner-
able population.

Identification of Vulnerable Population

The major hazards associated with a hurricane are: (1)
storm surge and saltwater flooding; (2) high winds; and (3)
fresh water flooding. In Sumter County the hazards relevant
to potential inland area evacuation are limited to freshwater
flooding and high winds.

Freshwater Flooding

Freshwater flooding occurs as a result of rainfall before,
during and after a hurricane. About 6 to 12 inches of rain-
fall can be expected to accompany a hurricane, although no
predictive tools are available for determining the rate and
geographic distribution of the rainfall. In Sumter County
the problems associated with freshwater flooding during a
hurricane include: lake and river flooding necessitating
evacuation of homes; and inundation of possible evacuation
routes. Freshwater flooding in the inland counties is
usually slowly rising water that does not create a life
threatening situation. The effects of early rainfall on
evacuation times are discussed in Chapter IV, Evacuation
Times.

Hurricane winds

Hurricane force winds are defined as attaining and
exceeding sustained wind velocities of 74 mph; sustained
winds being defined as the average wind value for 1 minute
interval. There have been reported cases of hurricane winds
reaching as high as 190 mph. In addition to sustained
winds, peak gusts are also a factor to consider.

Although the impact of sustained winds on large building
structures has been examined using wind-tunnel tests and
numerical modeling procedures, no experiments in the real
atmosphere have been conducted to determine the impact of
hurricane gusts on structures. However, it is clear that
sustained hurricane force winds and peak gusts can cause roof
failure, the outward collapse of walls and glass openings,
and enormous agricultural losses.

In Sumter Countymobile homes are the structures most
vulnerable to hurricane force winds. They are necessarily
of lightweight construction, with generally flat sides and
ends. Because of these characteristics, the winds of
hurricanes can toss mobile homes around, rolling them over
and over to complete the destruction. In addition, mobile
homes are also more susceptible to damage from flying debris.

Although local regulations require that mobile..home.s be
anchored to withstand high winds with "over-the-top" and
frame tiedowns, anchorage system requirements usually are
designed only to withstand a wind velocity of from 70 mph, to
100 mph. In addition, the threat of flying debris is not.
mitigated by tiedowns. Because hurricane winds can reach
190 mph, the National Weather Service recommends that mobile
home residents move to more sound structures prior to the
onset of hurricane winds.

Not only must the high winds hazard be considered for
its ability to damage property, but also for its ability to
interrupt evacuation efforts. Evacuation activities cannot
be safely carried out after the arrival of sustained gale
force winds (40 mph), generally several hours before hurricane
eye landfall. Therefore, it is recommended that all evacuees
should have completed their movement to safe destinations
before the arrival of these winds.

Population-At-Risk

The hazards of the hurricane will require the evacuation
of an estimated 9,113 persons in Sumter County.

Evacuation Destination Distribution

As part of the technical data for this plan, a statis-
tically significant survey of hurricane response behavior was

conducted in the Withlacoochee region.'/ One of the questions
asked in the survey was the evacuation destination. The
destinations were public shelter, friend or relative and
hotel/motel.

Based on the results of this survey and discussions with
the Regional Disaster Preparedness Advisory Committee, the
following evacuation destination distribution was developed
for the inland counties:

Evacuation Percentage of Population-At-Risk
Destination Seeking Destination

Public Shelter 53.8%
Friend or Relative 18.5%
Hotel/Motel 27.7%

It should be noted that, for the hotel/motel destination
there is not sufficient hotel/motel capacity to accommodate
the expected number of evacuees seeking this destination.
Therefore, those evacuees unable to obtain a hotel or motel
in Sumter County are assumed to seek such destinations outside
the region.

Tampa Bay Evacuees

Tampa Bay evacuation data has been analyzed by the
Florida Bureau of Emergency Management to estimate the 2/
number of evacuees expected to enter the Withlacoochee Region.

It is estimated tha t 114,455 persons seeking shelter
will enter the inland region. of these-evacuees, about 36,800
will seek public shelter. Only 9,080 shelter spaces are
available in Sumter County. Those not finding public shelter
will have to pass through to other areas.

'/Behavioral Surveys for the Withlacooche e Regional
DisastSr Preparedness Plan, H. W. Lochner, Inc., 1982.
"/Report on the Expected Coastal Demand for Inland
County Shelter Facilities-from the Tampa Bay and Southwest
Florida Regions, Florida Bureau of Emergency Management,
1982.

Evacuation Routes and Zones

As part of a transportation model of a hurricane evacu-
ation in the Withlacoochee region, the evacuation roadway
network for each county was designated.2/ This network is
displayed in Map 1 for Sumter County.

Another task of the transportation modeling effort was
to divide the counties into evacuating zones. Zones were
based on the roadway network and other easily identifiable
boundaries. These zones show the distribution of the population-
at-risk within the county and thereby assists in the allocation
of manpower and other resources within the county. Map 2
displays the evacuation zones developed for Sumter County.
Appendix A provides a written description of these zones.
Table 4 shows the distribution of the evacuation population
and number of vehicles, broken out by evacuation destination.

2/Transportation Analysis: Withlacoochee Regional
Hurricane Evacuation Plan, Post, Buckley, Schuh & Jernigan,
August, 1983.

S S201

301 MAP 1

0 66
00 103
S EVACUATION NETWORK
SUMTER COUNTY
Q Sol @oS02
\\ 44 Slol S12 S03
'9-20 S102
Sloo ildwood
470
SID 0

106 oleman
S04 S202
Sloa 470
'A05
S205 301
3109 S06
silo )- - - -4D 0
48 Sill S112
ushnelf
S07 3113 46 S14 Center Hill
116
478 S115 F-
CISOG 1 469 z
Webster D
S117 S09 6 0
204 Sio L)
4 .L --04 SI
78A S207o LJ
S203 50 y-
S119 <
-J
C 0 lie, j
S208

LEGEND

0 STREET OR INTERSECTION
LOCATION (NODE)
0 EVACUATION ZONE CENTER
(CENTROID)
S112 NODE OR CENTROID NUMBER 71
0

POLK COUNTY
4

5 10
Graphic Scale
Source: Post, Buckley, Schuh & Jernigan, Inc. Scale In Mi les
9

MAP 2
301
6 EVACUATION ZONES
SUMTER COUNTY
S@ S2

75
44 ildwood
470 S3

Coleman
S4

SO- 301
S6
48 S7
4T6 se 46 Cent r Hill
478
469 z
Webst r
0
S9 C)
4 r L e 4
w

0 0
C N

LEGEND

SO EVACUATION ZONE NUMBER

471

POLK COUNTY

5
10
Graphic Scale
Source: Post, Buckley, Schuh Jernigan, Inc. Scale In Miles

TABLE 3

INLAND SHELTER CAPACITY SUMMARY

LOCAL EVACUEES SHELTER SPACE REMAINING
SEEKING SHELTER (PRIMARY + SECONDARY)= TOTAL OPENINGS_

MARION 17,625 29,329 + 10,012 = 39,341 21,716

SUMTER 4,902 6,407 + 2,673 = 9,080 4,178

TABLE 4

SUMTER COUNTY EVACUATING POPULATION AT RISK AND EVACUATING VEHICLES

Evacuating Evacuating
Population 1 2 3 4 Vehicles 1 2 3 4
Zone #SOl 294 133
158 54 82 0 71 25 37 0
Zone #S02 1064 480
572 197 295 0 258 89 133 0
Zone #S03 578 261
311 107 160 0 140 48 72 0
Zone #S04 1785 806
960 330 494 0 433 149 223 0
Zone #S05 2384 1076
1283 441 660 0 579 199 298 0
Zone #S06 556 251
299 103 154 0 135 46 70 0
Zone #S07 265 119
142 49 73 0 64 22 33 0
Zone #S08 367 166
198 68 102 0 89 31 46 0
Zone #S09 1061 479
571 196 294 0 258 89 133 0
Zone #SlO 759 343
408 140 210 0 184 63 -95 0
9113 4902 1685 2524 0 4114 2211 761 1140 0

1 = Red Cross Shelter % Participation 100 Surge Zones
2 = Friends Home per Mobile Home Unit 2.7
3 = Hotel/Motel per Other Unit 2.7
4 = Do Not Know Avg. Veh. per D.U. 1.7
Veh. Usage % 71.7
Dist. %: S=53.8 FR=18.5 HM=27.7 DK=O

low' -W an go' low,

CHAPTER III

PUBLIC SHELTER CAPACITY

Primary and Secondary Shelters

Primary shelters consist of the public schools in Sumter
County which will be opened and used first in the event of a
evacuation. Table 5 presents the capacity of the primary public
shelters in Sumter County. About 6,407 persons could be
accommodated.
Secondary shelters in Sumter County are churches, meeting
halls and other public oriented buildings. The capacity of
secondary shelters is presented in Table 6.

More than sufficient space is available to shelter
local evacuees. However, if an evacuation order is issued
for both the Tampa Bay and Withlacoochee regions, all the
primary and secondary shelter capacity in Sumter County may
have to be-utilized. The implications of a Withlacoochee and
Tampa Bay evacuation on evacuation times are discussed in the
next chapter.

Shelter Duration Periods

The shelter duration period is defined as the minimum
period of time in which evacuees must remain in their evacu-
ation destination until the hurricane passes. This is defined
as the period of time before and after the occurrence of
gale force winds (32 - 63 mph). Gale force winds are assumed
to create hazardous conditions due to flying debris. These
times were calculated from the results of the SPLASH model
and are displayed in Table 7 for each hurricane type and
intensity. It should be noted that these are minimum shelter
duration periods and that actual shelter duration periods
may have to be increased depending on the results of the
storm.

TABLE 5

SUMTER COUNTY PRIMARY SHELTERS

Capacity
Primary Shelter Address 20 sq.f't./person

Bushnell Elementary School Flannery Ave., Bushnell 74-
FL 33531

North Sumter Intermediate Huey St., Wildwood, FL 462
School 32785

North Sumter Primary School Warfield Ave., Wildwood, 140
FL 32785

South Sumter High School Highway 475 North, 1692
Bushnell, FL 33513

South Sumter Middle School N. W. 10th Street, Webster, 948
FL 33597
1 ' I
Webster Elementary School Highway 471, Webster, FL 514
33597

Wildwood High School Huey St., Wildwood, FL 1532
32795

Wildwood Middle School Fruitland Park Road, 1045
Wildwood, FL 32785

TOTAL 6407

Source: Withlacoochee Regional Planning Council staff, Sumter
County Shelter Inventory, March, 1982.

TABLE ro,

SUMTER COUNTY ALTERNATE SHELTERS

Capacity
Secondary Shelter Address 20 sq. ft./person

First Baptist Church Creek Road & Hwy. 301, Oxford 264

First Baptist Church SR 470, Lake Panasoffkee 150

First Baptist Church lst Avenue & 2nd Street, Webster 300

Church of Christ 507 Gamble Ave., Wildwood 236

First Baptist Church Oxford St. & Mason Ave., Wildwood 1,000

First Baptist Church of 124 W. Anderson Avenue, Bushnell 206
God

Bushnell Presbyterian Church W. Dade Ave. and Broad St., Bushnell 97

First United Methodist W. Noble Avenue, Bushnell 70
Church

Wildwood United Methodist 308 North Mason St., Wildwood 100

First Baptist Church P. 0. Box 151, Center Hill 250

TOTAL 2,673

Source: Withlacoochee Regional Planning Council staff, Secondary Shelter
Inventory, March, 1983.

CHAPTER IV

EVACUATION TIMES

Evacuation times consist of three components: pre-
landfall hazard time, behavioral response time and clearance
time.

Pre-landfall hazard time is the number of hours before
the eye of the storm strikes or makes its closest point of
approach in which gale force winds occur. It is assumed
that evacuation must be completed before the occurrence of
gale force winds due to the potential.of hazardous driving
conditions. Pre-landfall hazard times are presented in
table 8 for each storm type and intensity.

Behavioral response time is the amount of time it takes
for the vulnerable population to respond to the evacuation
order. These times were based on the survey of hurricane
response behavior conducted in the Withlacoochee region and
previous evacuation studies and were calculated as part of
the transportation model.

Clearance time is the amount of travel time it takes
for the vulnerable population to reach their evacuation desti-
nations. This time was calculated as a part of the anspor-
tation model developed for the Withlacoochee region.

Evacuation time is the sum of these components. Tables
9 and 10 display the evacuation times by each level of vulner-
ability for each county in the Withlacoochee region. It can
be seen that evacuation times are greatly increased in some
counties, if both the Withlacoochee and Tampa Bay regions
are issued an evacuation order.

l/ Clearance time is calculated by determining which
link in the evacuation roadway network, displayed in Man 2,
is the most congested during the evacuation process. T@i,s
is called the "critical link". The amount of time it takes
for the last vehicle to "clear" this link is the clearance
time. Appendix B presents the distribution of traffic on
the roadway network in Hernando County according to the
evacuation scenarios developed for this report. The
critical links are denoted with an asterisk.

TABLE 7

GALE FORCE WIND ANALYSIS AND SHELTER DURATION PERIOD
BY STORM TYPE AND INTENSITY

Storm Storm Pre-landfall Shelter-Duration
Type intensity Hazard Time Period
Normal 5 7.01/ 12.03-/
Normal 4 9.0 15.0
Normal 3 8.0 14.0
Normal 2 6.0 11.0
Normal 1 5.5 9.5

Paralleling 4 8.0 17.0
Paralleling 3 7.0 15', 0
Paralleling 2 5.5 11.0
Paralleling 1 4.5 9.0

Exiting 2 5.5 13.0
Exiting 1 4.5 12.0

l/ Pre-landfall hazard time and shelter duration period
for storm intensity category five are shorter due to a narrower
radius of maximum winds

Source: SPLASH II computer output.

Timing Adjustments

(1) Evacuation order Adjustment. The behavioral response
time includes response time before and after the evacuation
order is issued. The amount of response time before.the
evacuation order is issued should be subtracted from the
evacuation times listed in tables 9 and 10 in order to arrive
at the minimum evacuation order time. These adjustments are
as follows:
Behavioral Response Adjustment
Behavioral Response Change in Evacuation Time

A (quick) subtract 1 hour,
B (medium) subtract 2 hours
C (slow) subtract 3 hours

forth in this report include the number of hours before eye
landfall (pre-landfall hazard time) when ambient high winds
might prevent evacuation from being carried out. However,
depending on the-structure, size, or forward speed of the
storm, hurricane-induced rainfall may precede this point in
time. Historically, rainfall has occurred as late as two
hours before eye landfall and as early as twenty hours before
eye landfall. Such rainf all would reduce.roadway carrying
capacity because of limited driver visibility and wet pave-
ment. This reduction has been estimated at approximately
fifteen percent in past transportation studies. This adjust-
ment requires a monitoring of the forecasted arrival of
rainfall by the local weather service office radar. If the
arrival of rainfall is forecasted substantially before the
pre-landfall hazards time an amount of time equal to about
fifteen percent of the clearance*time should be immediately
added to the evacuation time. The clearance time is the over-
all evacuation time minus the pre-landfall hazards time.

Based on the above, the following are the changes in
evacuation time according to behavioral response:

Rainfall Adjdstment
Behavioral Response Change in Evacuation Time

A add 1.5 hours
B add 1.5 hours
C add 2 hours

(3) Changes in Hurricane Parameters. Certain variables
were used Eo-predict wind speeds in the SPLASH model. If,
according to the monitoring of the storm before landfall,
these variables are different, the arrival of gale force winds
could change and thereby affect pre-landfall hazard times.

. The parameters in the SPLASH model which can affect the
arrival of gale force winds and thereby pre-landfall hazard
times are the forward speed of the storm and the radius to
maximum winds. As the storm speed increases, there is less
time required for the arrival of gale force winds, thereby
reducing pre-landfall hazard time. As the radius-to-maximum
winds increases, gale force winds arrive sooner, thereby
increasing pre-landfall hazard times.

In order to ascertain the sensitivity of pre-landfall
hazard times to the aforementioned, additional SPLASH program
runs were made. Forward speed and radius-to-maximum winds
were independently varied in each additional run. The results
are presented and explained in Table 8.

(4) Unpredictable Road Blockaaes. The intensity of traffic
during a hurricane evacuation will always be accompanied by
a certain number of traffic accidents and breakdowns.
Although roadway shoulders are available for.vehicles in dis-
tress, the movement of such vehicles to these areas is often
difficult and disruptive. It is recommended that at least
two traffic control personnel be positioned at each key road-
way link so that one can assist disabled vehicles as needed.
A tow vehicle should also be positioned at each critical link
to facilitate the removal of immobilized vehicles. Those
roadways that historically experience flooding due to rainfall
alone should be monitored for vehicle distress and help.

To guard against an unpredictable, and thus unquanti-
fiable blockage of evacuation routes that could add to the
overall evacuation time, a safety margin of up to two hours
will be added to the evacuation times. Such unpredictable
blockages could include.disabled vehicles, traffic accidents
and fallen trees or other debris.

Recommended Evacuation Times

It is recommended that a medium behavioral response be
used in determining the evacuation order time. It is also
recommended that two hours be added to the evacuation time
to account for unpredictable road blockages. Other adjust-
ments in evacuation times should be made as necessary
according to the previously mentioned adjustment factors.

TABLE 8

SENSITIVITY ANALYSIS OF PRE-LANDFALL
HAZARD TIMES

Storm Speed

Intensity Level Change in Storm Speed Change in Hazard Time

1 +15 mph -1.5 hrs.
2 +15 -2.0
3 +15 -4.0
4 +15 -4.0
5 +15 -3.0

Radius to Maximum Winds (RMW)-
Change in RMW Change in Hazard Time 2/

-10 -2
+10 +2
+20 +4
+30 +6

l/ Changes in pre-landfall hazard times for other changes
in storm speed can be determined from this table. For example,
if the storm speed is forecasted 10 mph greater than the storm
speed used in the SPLASH model, which is 15 mph, the resultant
change in storm speed is proportional. The hazard times will
increa e only if the forecasted storm speed is less than 15 mph.
2@Generally there is a 2 hour change in hazard time for
every 10 mile change in RMW. The RMW used in the SPLASH model
are shown in table 1.

SOURCE: SPLASH II computer printouts prepared by the National
Hurricane Center.

Based on the above recommendations, the following is a
range of recommended evacuation order times:

Recommended Evacuation Time

11 3/4 - 28 1/2 hours

The times represent minimum evacuation order times,
excluding previously mentioned adjustment factors. These
times should be adjusted, using these factors, according to
forecasted hurricane conditions. Please refer to tables 1
and 2.

TABLE 9

REGIONAL VULNERABILITY LEVELS

Storm Description/Saffir-
Vulnerabilty Level Simpson Intensity Category

A Exiting hurricane, category 1-2
Paralleling hurricane, category 1-2
Normal hurricane, category 1-2

A w/Tampa Bay Same as vulnerability level A, Tampa
Bay Region also evacuates

B Paralleling hurricane, category 3-4
Normal hurricane, category 3-5

B w/Tampa Bay Same as vulnerability level B,
Tampa Bay Region also evacuates

TABLE 10

EVACUATION TIMES (in hours)

VULNERABILITY LEVEL 'A'

REGIONAL VULNERABILITY LEVEL
Response A w/Tampa Bay
-Curve A Evacuation

Levy County A-Quick Response 8 3/4 - 12 1/4 83/4 - 12 1/4
B-Medium Response 11 3/4 - 15 1/4 11 3/4 - 15 1/4
C-Slow Response 14 3/4 - 18 1/4 14 3/4 - 18 1/4

Citrus County A-Quick Response 12 1/4 - 15 3/4 12 1/4 - 15 3/4
B-Medium Response 14 17 1/2 14 - 17 1/2
C-Slow Response 16 19 1/2 16 - 19 1/2

Hernando County A-Quick Response 8 3/4 12 1/4 29 1/2 - 33
B-Medium Response 12 15 1/2 30 - 33 1/2
C-Slow Response 15 18 1/2 30 3/4 - 34 1/4

Marion County A-Quick Response 9 1/2 13 1/2 22 1/2 - 26
B-Medium Response 12 1/2 - 16 24 - 27 1/2
C-Slow Response 15 1/2 - 19 25 1/2 - 29

Sumter County A-Quick Response 9 - 12 1/2 22 1/2 - 26
B-Medium Response 11 3/4 - 15 1/4 24 -27 112
C-Slow Response 14 1/2 - 18 1/4 25 1/2 29

SOURCE: Post, Buckley, Schuh & Jernigan, Inc. and WRPC Staff.

TABLE 11

EVACUATION TIMES (in hours)

VULNERABILITY LEVEL IBI

REGIONAL VULNERABILITY LEVEL
Response B w/Tampa Bay
-Curve B Evacuation
Levy County A-Quick Response 10 3/4 - 13 3/4 11 3/4 - 14 3/4
B-Medium Response 14 1/4 - 16 1/4 14 1/4 - 16 1/4
C-Slow Response. 17 1/4 - 19 1/4 17 1/4 - 19 1/4

Citrus County A-Quick Response 16 1/4 - 18 1/4 16 1/4 - 18 1/4
B-Medium Response 18 - 20 18 - 20
C-Slow Response 20 - 22 20 - 22

Hernando County A-Quick Response 15 1/4 - 18 1/4 32 - 34 1/2
B-Medium Response 15 1/4 - 17 1/4 32 1/2 - 34 1/2
C-Slow Response 17 1/2 - 19 1/2 33 1/4 - 35 1/4

Marion County A-Quick Response 12 - 14 25 1/4 - 27 1/4
B-Medium Response 15 - 17 26 3/4 - 28 3/4
C-Slow Response 18 - 20 28 1/4 - 30 1/4

Sumter County A-Quick Response 11 1/2 - 13 1/2 25 - 27
B-Medium Response 14 1/4 - 16 1/4 26 1/2 - 28 1/2
C-Slow Response 17 1/4 - 19 1/4 28 - 30

SOURCE: Post, Buckley, Schuh & Jernigan, Inc. and WRPC Staff

CHAPTER V

WARNING INFORMATION

Warning information refers to the flow of information'
on the need for hurricane evacuation from the National Hurri-
cane Center to the general public. The purpose of this
chapter is not to propose a new method for the dissemination
of warning information, but rather to explain the existing
system.

Agency Participants and.Warning Process

The following are the principal Federal, State and
local governmental agencies involved in the warning system:

- National Hurricane.Center, Miami
- Tampa Area Office, National Weather service, Ruskin
- Florida Bureau of Emergency Management, Tallahassee
- Central Florida Area office, Florida
(Bureau of Emergency Management, Wildwood)
- County Civil Defense Department
Public Media (TV/Radio)

The warning process is initiated by the National Hurri-
cane Center and reaches the public through the following
five-step procedure:

1. A potential hurricane picked up in satellite
images is usually the subject of the first of
a series of advisory messages issued by the
National Hurricane Center at six hour intervals
(5 and 11 A.M. and P.M., Eastern Standard Time).
These early advisories are aimed mainly at
shipping and aviation interests. When the storm
intensifies further into a tropical storm, it is
given a name.

2. If-the hurricane or tropical storm approaches
land, the advisory information begins to focus
on coastal and inland effects.

A Hurricane Watch announcement becomes part of
the NHC advisories when the storm threatens
coastal and inland areas. This Watch covers a
specified area and period of time and means that
hurricame conditions are a real possibility.

A Hurricane Warning is added to the advisory when
hurricane condiFiUons, winds of at least 74 miles
per hour, high water and storm tides, are expected
within a period of up to 24 hours. The Warning
identifies coastal areas where these conditions
are expected to occur.

3. As the threat to coastal areas becomes more apparentl
the advisories are then interspersed with inter-
mediate advisories every three hours or as needed.

4. once a hurricane becomes a threat to the Withla-
coochee Region, then the Tampa Area office of the
National Weather Service will add local statements
to each NHC advisory and intermediate advisories.
The local statements will consist of recommendations
for precautionary actions and completion times,
existing conditions of wind and tides, information
regarding projected storm tides confronting counties
of the region.

5. All normal warning information will be provided to
the general public through the media (radio/TV) by
the NHC and when necessary, local government.

The warning information provided by the hurricane advi-
sories, intermediate advisories and local statements will be
used as a basis to alert local officials and disaster organi-
zations of any potential hurricane threat. These warnings
are augmented by restricted information to local governments
also furnished by the NHC to assist those governments in
preparation and evacuation decision-making. This restricted
information is normally received over the National Warning
System (NAWAS) by the Department of Civil Defense, or, when
activated, the Sumter County Emergency Operations Center (EOC).

On the basis of the aforementioned warning procedure,
the Governor of Florida is advised by the State Bureau of
Emergency Management to issue an evacuation-order for the
affected local area; or, the chief elected official of each
affected local political jurisdiction may issue the evacu--
ation order, as advised by its disaster preparedness agency
or committee.

The Central Florida Area Office will serve as the lead
agency for coordinating an interregional evacuation, which
is described in Chapter VI, Regional Coordinative Mechanism.

Local disaster preparedness agencies and other agencies,
such as fire districts, Red Cross and Sheriffs'Departments
will be the key agencies in carrying out the evacuation.

The following is a chronological summary of key warning
conditions, based on the above information, in relation to
the number of hours before projected hurricane eye landfall
or closest point of approach:

- 72 hour advisory: storm assigned Category number on..
Saffir/Simpson Scale by NHC (See Appendix B for a
description of the Saffir/Simpson scale)
- 48 hours before projected eye landfall: local
areas placed under hurricane watch condition by NHC
- 24 hours before projected eye landfall-.@ local
areas placed under hurricane warning condition by NHC
- 12-24 hours before projected eye landfall: local
area advised to evacuate by NHC advisory or local NWS
office Local Action Statement
- Governor advised by Bureau of Emergency Management
to issue an evacuation order for the local area or
County Commissionadvised to issue an evacuation order
by the Civil Defense Director, the local evacuation
order should be issued according to the recommended
evacuation order times in this guide.

CHAPTER VI

REGIONAL COORDINATIVE MECHANISM

Regional Evacuation Scenarios

For purpose of this report, "regional" is defined.as
.affecting more than one county. Accepting-this definition,
the hurricane is definitely a regional event. This is 'not
only because its hazards can affect a relatively large area,
but also due to the error in prediction as to where.the hurri-
cane will strike, or make.--its closest point of approach (CPA)
during the hurricane warning period, typically 12 to 24 hours
before CPA. It is possible that up to a 250-mile "warning
area" along.the coast may occur during the warning period
due to this error in prediction. Therefore, it is possible
that, for example, both.the Withlacoochee and the Tampa Bay
regions may fall under this "warning area" and, hence, have
to be evacuated.

It should be further noted*that the rate of reduction of
hurricane-force winds after the hurricane makes its closest
point of approach is largely unpredictable. Therefore, it
is assumed that the mobile-home residents in the inland
counties will have to evacuate regardless of the type or
intensity of the hypothetical hurricane tracks modeled in the
SPLASH computer model, should an evacuation order be issued
for the inland counties.

Based upon the above information, three regional evacu-
ation scenarios have been designated for purposes of this
report. They ar e as follows:

Regional Scenario A: includes all of the residents
within the evacuation zones associated with Vulner-
ability Level 'A' in the coastal counties, the
mobile-home residents in the remainder of the coastal
counties and the mobile-home residents in the inland
couniies.

Regional Scenario B: includes all of the residents
within the evacuation zones associated with Vulner-
ability-Levels A and B, the remainder of the coastal
mobile-home residents and inland mobile-home residents.

Regional Scenario C: includes all of the residents in
Regional Scenario B and the number of persons entering
the Withlacoochee region from the Tampa Bay region,
based on the worst-case regional evacuation scenario
f or the Tampa Bay region.

The aforementioned scenarios do not cover all the possi-
bilities in that it is possible that, for example, only the
northern counties of Levy and Marion need be evacuated should
the "warning area" be further to the north. The same applies
to the southern counties of Citrus, Sumter and Hernando;
should it be further to the south. It is also possible that
the Tampa Bay region may be evacuated without any of the
counties in the Withlacoochee region evacuated. Thus, the
regional scenarios should be viewed as worst-case planning
possibilities, based on currently available information.

The population-at-risk for each regi onal scenario is
shown below:
Regionwide
Regional Scenario Population-At-Risk

A 98,742,
B 112,232
C 255,742

Implications for Evacuation Decision-Making

The evacuation times for Sumter County are influenced
by the extent of the evacuation traffic from the Tampa Bay
region. The influx from this area will generate additional
traffic that will slow the local evacuation of mobile homes.

Evacuees entering from the coastal area of Hernando,
Citrus and Levy Counties will be limited to those seeking
shelter at friends, relatives or hotel/motel.

Regional Coordination

Lead Agency

To effectively coordinate a regional response to a
hurricane emergency,.a lead agency must be designated to pro-
vide a linkage among the organizational participants. The
lead agency must have jurisdiction over a multi-county area,
and possess sufficient expertise, staff and funding to effec-
tively manage the evacuation. A reliable communication
system is also crucial for the overall coordination of the
evacuation.

It is proposed that the Central Florida Area office for
the Bureau of Emergency Management (CEFA) located in Wildwood,
be designated as the lead agency for interregional evacuation
management. While other entities were considered for desig-
nation as lead agency,-CEPA appears to be best qualified for
terms of the criteria mentioned above. (See Figure
As the lead agency with overall re'sponsibilities for
coordination in the Withlacoochee Region, CEFA will serve
as the focal point for the flow bf information on hurricane
warnings, evacuations and shelter openings.

Regional Entities.

Organizations thaf will be involved at the regional
level include the Florida Highway Patrol, the Red Crods and
the Health and Rehabilitative Services Department. The FHP
maintains traffic control and Maintains the progress of the
evacuation. Continuous communication with the regional EOC
will provide up-to-the-minute information on the evacuation
and thereby improved decision-making during the emergency.
The Red Cross will be involved at the regional level in the
opening and staffing of shelters. The regional office of the
Red Cross would assist in areas without a local Red Cross
Chapter. 'The State Department,of HRS provides manpower
assistanc@_, to the Red Cross should insufficient personnel-be
available for staffing of hurricane shelters.

Figure 1

Emergency Facility Profile

Name

Central Florida Area Office (CEFA),
Bureau of Emergency Management

Location

E. C. Rowell Building
S.R. 301 & 44A
Wildwood, Sumter County

Communication Systems:

- Standard Phone line
- Local Government Radio (18 counties, daily roll call)
- National Warning System (NAWAS - dedicated telephone
line, some counties only)
- State Warning System (telephone line)
- "Hot ring" to nuclear plant and Levy and Citrus
Countie s
- Emergency Telephones - 16 telephones

Staffing

Normal Conditions - Hours 8 a.m. - 5 p.m., 14-F
Secretary
Communicator
Local Government Assistance Representative

Emergency Conditions - 24 hours until emergency is over.
In addition to normal staff, representatives from
State agencies are present at the site (e.g. Florida
Highway Patrol)

Other Facilities

EOC Room, Status Board, area-wide maps

Procedures for Implementation of the Interregional
Evacuation Plan

To be effective, the plan for interregional evacuation
must contain a coordinative mechanism to establish procedures
for the opening of shelters and reception sites in coordi-
nation with evacuation movements. The proposed procedures
for implementation of the interregional plan are described
below for each phase of the hurricane emergency.

Normal Conditions

Representatives of the participating agencies involved
in the plan will meet on a regular basis to enhance ongoing
coordination among the agencies and identify problems with
the implementation of the plan.

This group should meet as a permanent committee, and
focus on the regional aspects of hurricane planning and
operations. Activities of the committee may include:

- testing of the plan;
- review of the institutional arrangements for
coordination;
- improvement of public awareness of hurricane hazards;
exchange information on ways to improve disaster
response and recovery.

Emeraency Conditions

As a hurricane develops and threatens land areas, the
National Hurricane Center will issue a hurricane watch twenty
four to forty-eight hours before landfall. This alerts
threatened areas to potential storm conditions. A hurricane
warning should be issued according to the recommended evacu-
ation order times in this report. These warnings are issued
to the State Bureau of Emergency Management as well as county
civil defense offices.2/

2/It s hould be noted that warning times may have to be
revised in light of the evacuation times calculated for the
county.

Post Emergency Conditions

As the hurricane hazard recedes from the region, the
Area Coordinator should continue to act as the liaison between
coastal and inland counties. Information on when it is-safe
to return to effected areas can be transmitted to the inland
county civil defense offices. The Area Office should also
assist where ever possible in an expedient and effective
disaster recovery process.

After recovery has been completed, the interregional
committee should meet to evaluate the plan as implemented
and identify any problems that may have occurred.

Public Notification

During non-emergency periods, public information and
education is disseminated by various agencies through news
releases, news features, and radio and television programs.
Such activity serves to increase awareness of emergency
preparedness programs and provides the citizens with a
knowledge of the basic precautions necessary during an
emergency.

During emergency periods, it is necessary to provide the
public with clear, concise, and timely information and
instructions to the general public. It is important that one
single agency in each Jurisdiction be designated as the
sources of public information in an emergency. This will
avoid the issuance of conflicting reports and provide a con-
tinuous flow of information regarding governmental decisions,
recommendations and instructions. Public notification and
instructions will be issued by the civil preparedness agency
within each respective jurisdiction. This information should
be disseminated after consultation and coordination with the
Central Florida Area office, Bureau of Emergency Management.

While primary responsibility for public notification is
conferred,to the respective civil preparedness agencies, it
is suggested that the procedures below be incorporated into
the public notification process to improve interregional
coordination. These suggestions are divided into three
phases: normal, emergency, and post emergency conditions.

Normal

Public information materials developed as part of the
Regional Hurricane Evacuation Plan (and prepared by the Regional
Planning Council) should be disseminated to coastal and
inland residents. This material will educate the public on
hurricane hazards, and provide instructions based on the
findings of the inland shelter study. The material will
identify the sources of further information and assistance
during the emergency phase.

Emergency

It is suggested that as the emergency approaches, an
emergency public information officer be activated to act as
the only official sources of public information for that
jurisdiction. This officer should be pre-designated and in
constant communication with the National Hurricane Center,
surrounding EOC's and CEFA.

Evacuation and sheltering instructions on cassette tapes
or radio scripts which have been prepared beforehand can be
dissminated at this time. In the print media, area news-
papers could print hurricane supplements which have been
prepared in cooperation with the civil preparedness agency.

Post Emergency

In this phase the public information officer should
continue to be the official source of public information
and should receive information*from various service agencies
for dissemination to the public. The officer should assist
State and Federal officers in local dissemination of infor-
mation concerning their programs.

Personnel for Reception Centers and Shelters

I
Assignment and notification of personnel to emergency
facilities is the responsibility of the county civil defense
director. The mobilization of emergency personnel will
follow the issuance of an evacuation order. Through consul-
tation with CEFA, the civil defense director should have a
good idea of the timing and scope of the evacuation in
coastal areas. He may then mobilize county resources to the
required level.

To(ensure that shelters and reception centers are pro-
perly staffed in an emergency, it is suggested that procedures
be established for assignment and notification of personnel.
These procedures should be developed as part of a plan of
action that is consistent with the regional plan and relevent
to the needs and resources of the county.

Suggested Plan of Action

Key members of county government, the Red Cross and
other agencies should meet with the civil defense directors as
a group to establish the roles and responsibilities of the!
participants. A plan of action can be devised to acquaint:
each member with the duties that his organization is expected
to perform.

The group or committee is put on call with the issuance
of the hurricane watch. Key members of the committee (those
in charge of a county division for example) would meet with
the civil defense officer to review plans, and determine
readiness of equipment, supplies and personnel.

Several hours prior to the recommended evacuation order
times, the key personnel would activate their departmental or
agency emergency plans, and alert and maintain communications
with personnel. As evacuations are announced, the committee
would monitor the situation and respond to instructions from
the civil defense officer.

Prior to the recommended evacuation order time, the EOC
should be fully operational with each participant performing
assigned duties and.tasks. Emergency operations would be in
full swing and involve several different areas:

- communication with the Red Cross for shelter openings
- broadcast of hurricane precautions
- communications with public utilities
- law enforcement: patrols, road blocks, rescues
- coordination of emergency services and needs

With the onslaught of the hurricane, activities in the
effected areas are halted. The progress of the storm and
emergency operations are monitored at the EOC.

After the danger has passed, post disaster operations
will be initiated. A written report and evaluation should
be provided to the civil defense officer.

CHAPTER VII

LOCAL COORDINATION

The specific roles and responsibilities for hurricane
evacuation in Sumter County are described in the Peacetime
Emergency Plan. The local government is charged with the
following tasks regarding local evacuation.

1. Provide local law enforcement resources for
evacuation traffic control.

2. Coordinate the provision of welfare support
to individuals and families, to include
shelters, food, clothing and medical supplies.

3. Provide local law enforcement resources to
provide security for evacuated areas.

4. Maintain plans identifying procedures necessary
to ensure safe and orderly evacuation of
threatened areas.

5. Based upon information and existing conditions,
recommend or order evacuation.

6. Activate procedures related to public informa-
tion and warning as necessary for support of
evacuation.

7. Coordinate provision of local transportation
assets to supplement use of private vehicles
for evacuation.

8. Ensure that equipment is available for expedi-
tious removal of disabled vehicles and debris
from evacuation routes.

It should be noted that local evacuation may need to be
accelerated in order to cope with an influx of traffic from
other regions such as Tampa Bay. Local officials should
adjust the timing of the evacuation order to account for
delays caused by this additional traffic congestion.

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APPENDIX A

SUMTER COUNTY
EVACUATION ZONE BOUNDARIES

Evacuation
Zone Zone Boundary Description

S1 South of Sumter County line; west of CR 466, Wildwood city
limit and railroad; north of Lake Panasoffkee and Outlet River;
east of Sumter County line

S2 South of Sumter County line; west of Sumter County line; north
of railroad and Wildwood city limit; east of CR 466

S3 Wildwood city limits; SR 35 area south to Florida* Turnpike

S4 South of railroad and Florida Turnpike; west of Sumter County
line; north of CR 470; east of CR 471, Coleman city limits and
railroad

S5 South of Outlet River and Lake Panasoffkee; west of railroad
and Bushnell city limit; north of CR 476; east of Sumter County
line

S6 South of Shady Brook and CR 470; west of Sumter County line;
north of CR 476 and Center Hill city limit; east of railroad and
Bushnell city limit

S7 B ushnell city limits; one square mile area northwest of city

S8 South of CR 476 and Bushnell city limit; west of CR 471; north
of CR 478 and railroad; east of CR 476B

S9 South of CR 476, CR 476B, CR 478 and railroad; west of CR
471 and Webster city limit; north of Sumter County line; east of
Sumter County line

Slo South of CR 476, Center Hill northern city limit and railroad;
west of Sumter County line; north of Sumter County line; east
of Sumter County line and CR 471

A-1

APPENDIX B

THE SAFFIR/SIMPSON HURRICANE SCALE

The Saffir/Simpson Hurricane Scale is used by the National
Weather Service to give public safety officials a continuing
assessment of the potential for wind and storm surge damage
from a hurricane in progress. Scale numbers are made avail-
able to public safety officials when a hurricane is within
72 hours of landfall. Scale assessments are revised regularly'
as new observations are made, and public safety organizations
are kept informed of new estimates of the hurricane's disaster
potential.

Scale numbers range from 1 to 5. Scale No. 1 begins with
hurricanes in which the maximum sustained winds are at least
74 mph, or which will produce a storm surge 4 to 5 feet above
normal water level, while Scale No. 5 applies to those in
which the maximum sustained winds are 155 mph or more, which
have the potential of producing a storm surge more than 18
feet above normal.

The scale was developed by Herbert Saffir, Dade County,
Florida, consulting engineer, and Dr. Robert H. Simpson,
former National Hurricane Center director, and projects scale
assessment categor.ies as follows:

Category No. 1 - Winds of 74 to 95 mph. Damage primarily
to shubbery, trees, foliag(@, and unanchored mobile homes.
No real damage to other structures. Some damage to
poorly constructed signs. Storm surge 4 to 5 feet above
normal. Low-lying coastal roads inundated, minor pier
damage, some small craft in exposed anchorage torn from
moorings.

Category No. 2 - Winds of 96 to 110 mph. Considerable
damage to shrubbery and tree foliage; some trees blown
down., Major damage to exposed mobile homes. Extensive
damage to poorly constructed signs. Some damage to
roofing materials of buildings; some window and door
damage. Coastal roads and low-lying escape routes
inland cut by rising water two to four hours before
arrival of hurricane center. Considerable damage to
piers. Marinas flooded. Small craft in unprotected
anchorages torn from moorings. Evacuation of-some
shoreline residences and low-lying island areas required.

NNW

APPENDIX B

category No 3 - Winds of 111 to 130 mph. Foliage torn
from trees; large trees blown.down. Practically all
poorly constructed signs blown down. Some damage to
roofing materials of buildings; some window and door
damage. Some structural damage to small buildings.
Mobile homes destroyed. Storm.surge 9 to 12 feet above
normal. Serious flooding at coast and many smaller
structures near coast destroyed; large structures near
coast damaged by battering waves and floating debris.
Low-lying escape routes inland cut by rising water
three to five hours before hurricane center arrives.
Flat terrain 5 feet or less above sea level flooded
inland 8 miles or more. Evacuation of low-lying resi-
dences within several blocks of shoreline possible
required.

Category No. 4 - Winds of 131 to 155 mph. Shrubs and
.trees blown down; all signs down. Extensive damage to
roofing materials, windows, and doors. Complete failure
of roofs on many small residences. Complete destruction
of mobile homes. Storm surge 13 to 18 feet above nor-
mal.. Flat terrain 10 feet or less above sea level flooded
inland as far as six miles. Major damage to lower floors
to structures near shore due to flooding and battering
by waves and floating debris. Low-lying escape routes
inland cut by rising water three to five hours before
hurricane center arrives. major erosion of beaches..
massive evacuation of all residences within 500 yards
of shore possibly required, and of single-story resi-
dences on low ground within two miles of shore.

Category No. 5 - Winds greater than 155 mph. Shrubs
and trees blown down; considerable damage to roofs on
many residences and industrial buildings. Extensive
shattering of glass in windows and doors. Some complete
building failures. Small buildings over-turned or blown
away. Complete destruction of mobile homes. Storm
surge greater than 18 feet above normal. Major damage
to lower floors of all structures less than 15 feet
above,sea level within 500 yards of shore. Low-lying
escape routes inland cut by rising water three to five
hours before hurricane center arrives. Massive evacu-
ation of residential areas on low ground within five to
ten miles of shore possible required.

Dr. Neil Frank, present National Hurricane Center director,
has adapted atmospheric pressure ranges to the Saffir/Sampson
Scale. These pressure -ranges, along with a numerical break-
down of wind and storm surge ranges are:

B-2

APPENDIX B

SCALE CENTRAL PRESSURES WINDS SURGE
NUMBER MILLIBARS INCHES (MPH) (FT.) DAMAGE

1 .980 28.94 74- 95 4- 5 Minimal
2 965-979 28.5 -28.91 96-110 6- 8 Moderate
3 945-964 27.91-28.47 111-130 9-12 Extensive
4 920-944 27.17-27.88 131-155 13-18 Extreme
5 920 27.17 155+ 18+ Catastrophic

B-3

WITHLACOOCHEE REGIONAL PLANNING COUNCIL

STAFF

James D. Mims Ed Isenhour
Executive Director Planning Intern

Lorene Finch William Scarff
Administrative Assistant Research Assistant/Housing
Rehabilitation Specialist

Peggy Alexander Vivian A. Whittier
Finance Director Research Assistant/Information
Specialist

Charlotte Neupauer Lynn Rich
Full Charge Bookkeeper Research Assistant/Information
Specialist

William E. Taylor Glenda Roberts
Graphics Chief Secretarial Supervisor

Joyce E. Cusick Kim Greene
Senior Planner/Community Secretary II
Development

*Kevin Smith Dedra Freeman
Principal.Planner Secretary I

Mark Sinclair Tonja Edmondson
Principal Planner General Clerical Assistant

Oliver Pinkston Doris Pullings
Planning Intern General Clerical Assistant

Taylor Warner
Planning Intern

*Planner responsible for the preparation of this report.

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