Alert archive / Florida / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 135, NWS Tampa Bay, FL

August 18, 2001Sarasota County, Florida

NWS Tampa Bay, FL issued this severe thunderstorm warning at Aug 18, 2001, 4:28 PM EDT for Sarasota County, Florida. It was in force for 47 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 18, 2001, 4:28 PM EDT (20:28 UTC)
Expired: Aug 18, 2001, 5:15 PM EDT
In force: 47 min
Issued by: NWS Tampa Bay, FL
Area: Whole counties

County Sarasota County, FL

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 12:00Z, 8.5 hours before the alert went out and 58 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 23 minutes earlier.

Area forecast discussion, Aug 18, 2:05 PM EDT, 2 hours 23 minutes 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.

Issued	Product	Office	Counties	Lasted
Aug 18, 4:05 PM EDT	Severe Thunderstorm Warning	TBW	Polk	25 min

Nearby

Severe Thunderstorm Warnings in Florida, 2001 Every 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; the sounding from the Mesonet's radiosonde archive.