Alert archive / Florida / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 134, NWS Tampa Bay, FL

August 18, 2001Polk County, Florida

NWS Tampa Bay, FL issued this severe thunderstorm warning at Aug 18, 2001, 4:05 PM EDT for Polk County, Florida. It was in force for 25 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Aug 18, 2001, 4:05 PM EDT (20:05 UTC)
Expired
Aug 18, 2001, 4:30 PM EDT
In force
25 min
Issued by
NWS Tampa Bay, FL
Area
Whole counties

County Polk County, FL

What was reported inside it

TimeReportWhereRemark
Aug 18, 4:10 PM EDTThunderstorm WindLakeland, FLA Skywarn Spotter reported that thunderstorm winds uprooted several large trees south of the intersection of U.S. Highway 98 and Rock Ridge Road.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 12:00Z, 8.1 hours before the alert went out and 74 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Tampa Bay, FL at 12:00Z on 2001-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2466 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tampa Bay, FL at 12:00Z on 2001-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 1 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
2466 J/kg
Mixed-layer CIN
-26 J/kg
Mixed-layer LCL
764 m above ground
0-6 km bulk shear
4 kt
0-1 km storm-relative helicity
1 m²/s²
0-3 km storm-relative helicity
13 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

419 
WUUS52 KTBW 182006
SVRTBW
FLC105-182030-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
405 PM EDT SAT AUG 18 2001

THE NATIONAL WEATHER SERVICE IN RUSKIN HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHWESTERN POLK COUNTY IN FLORIDA.

* UNTIL 430 PM EDT.

* AT 405 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM WITH LARGE HAIL...OVER NORTHWESTERN POLK
  COUNTY...MOVING NORTHEAST AT 5 MPH.

* THE SEVERE THUNDERSTORM WILL AFFECT...
  RURAL AREAS NORTH OF KATHLEEN AND ALONG HIGHWAY 98.

SEVERE THUNDERSTORMS CONTAIN WIND GUSTS OF 60 MPH OR HIGHER...AND
HAIL THE SIZE OF DIMES OR LARGER. MOVE TO A PLACE OF SAFETY.

$$

LAT...LON 2824 8211 2805 8197 2824 8188 2831 8201

33
NNNN

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Tampa Bay, FL wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 18, 2:05 PM EDT, 2 hours earlier.

Area forecast discussion, Aug 18, 2:05 PM EDT, 2 hours before
WEST CENTRAL AND SOUTHWEST FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
205 PM EDT SAT AUG 18 2001

CURRENTLY...CONVECTION JUST BEGINNING ALONG THE WEST COAST SEA
BREEZE. VISIBLE LOOP INDICATES LOW LEVEL RIDGE AXIS OVER THE CENT FA.
CONVECTION ALSO FIRING ALONG SEA BREEZE OVER SE FL...AND IS MOVING
WNW TOWARD THE SW FA. HEAT INDICES ALREADY NEAR 103...WITH INTERIOR
LIKELY TO REACH 105. SLOW STORM MOTIONS AND HIGH PWS SHOULD LEAD TO
THE POTENTIAL FOR LOCALLY HEAVY RAINFALL. EXPECT CONVECTION TO PUSH
INLAND FROM TPA NORTH BY LATE AFTN/EARLY EVENING.

--FCST DISC--
LITTLE CHANGE IN OVER ALL PATTERN THROUGH MON. UPPER TROF DIGS OVER
THE EASTERN U.S. THROUGH THE PERIOD...WHICH HELPS TO LOWER MID/UPPER
HTS OVER THE FA. ASSOCIATED SFC FRONT/TROF REMAINS WELL NORTH OF THE
FA OVER SCENT GA. DESPITE UPPER HTS FALLS...THE SFC RIDGE AXIS SEEMS
TO SIT GENERALLY OVER THE CENT FA/PENIN...KEEPING RELATIVELY LIGHT
FLOW. AS PREVIOUS FCSTRS HAVE MENTIONED...LOWERING OF MID/UPPER HTS
SHOULD LESSEN LARGE SCALE SUBSIDENCE...AND HELP INCREASE CONVECTIVE
COVERAGE SUN AND MON. WILL CONTINUE TO TREND POPS SLOWLY UPWARD SUN
AND MON...WITH 40-50% SUN...AND 50-60% MON. THIS FITS THE AVN TREND
IN POPS...AND IS ALSO CLOSE TO CLIMO. FWC POPS SEEM TOO LOW GIVEN
DEEP MOISTURE AND LOWERING UPPER HTS. HUMIDITY LEVELS EXPECTED TO
REMAIN HIGH GIVEN LITTLE/NO CHANGE IN AIRMASS.

--EXTENDED--
MUCH OF THE EXTENDED PERIOD DEPENDS ON THE FATE OF CHANTAL. USING
NHCS LATEST FCST TRACK...PLACES THE SYSTEM SOMEWHERE OVER THE
NORTHERN YUCATAN PENINSULA BY LATE MON AND TUES. WILL KEEP FCST
VERY CONSERVATIVE FOR NOW...AND HOLD POPS GENERALLY NEAR CLIMO
THROUGH SAT. MAIN EFFECTS FOR NOW WILL LIKELY BE IN THE MARINE.

--MARINE--
NO PROBLEMS THROUGH THE WEEKEND. GIVEN POTENTIAL UNCERTAINTIES WITH
THE TRACK OF CHANTAL...WILL BEGIN TRENDING WINDS AND SEAS UPWARD OVER
THE S WATERS MON AND TUE...AND LIKELY ALL AREAS BY LATER TUE AND
WED. TOO EARLY TO TELL WHETHER ANY HIGHLIGHTS WILL BE NEEDED.

PRELIM S:
TPA 078/092 078/090 2435
FMY 077/093 077/091 3546=

.TBW...NONE.

MORALES

The office that day

Everything else NWS Tampa Bay, FL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 18, 4:28 PM EDTSevere Thunderstorm WarningTBWSarasota47 min

Nearby

Severe Thunderstorm Warnings in Florida, 2001Every severe thunderstorm warning in 2001

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.