Alert archive / Florida / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 24, NWS Tampa Bay, FL

March 31, 2001Polk County, Florida

NWS Tampa Bay, FL issued this severe thunderstorm warning at Mar 31, 2001, 4:15 PM EST for Polk County, Florida. It was in force for 25 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: Mar 31, 2001, 4:15 PM EST (21:15 UTC)
Expired: Mar 31, 2001, 4:40 PM EST
In force: 25 min
Issued by: NWS Tampa Bay, FL
Area: Whole counties

County Polk County, FL

The radar

The Tampa radar (KTBW), 74 km from the middle of the area, began a volume at 21:15 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Cape Canaveral, FL (KXMR), launched 12:00Z, 9.3 hours before the alert went out and 131 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: 1036 J/kg
Mixed-layer CIN: -13 J/kg
Mixed-layer LCL: 575 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 22 m²/s²
0-3 km storm-relative helicity: 44 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 1.0

Open this sounding in Storm Lab

The text

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

000 
WUUS52 KTBW 312117 CCA
SVRTBW

FLC105-312140-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING...COR EXP TIME IN HEADER
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
415 PM EST SAT MAR 31 2001

THE NATIONAL WEATHER SERVICE IN RUSKIN HAS ISSUED A

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

* UNTIL 440 PM EST.

* AT 415 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM WITH LARGE HAIL...6 MILES SOUTH OF HAINES
  CITY...MOVING EAST AT 40 MPH.

* THE SEVERE THUNDERSTORM WILL AFFECT...
  HAINES CITY.

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

$$


13
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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 Mar 31, 3:15 PM EST, 1 hour earlier.

Area forecast discussion, Mar 31, 3:15 PM EST, 1 hour before

WEST CENTRAL AND SOUTHWEST FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
315 PM EST SAT MAR 31 2001

WILL CANCEL FLOOD WATCH WITH THIS PACKAGE. WE ARE GETTING LOCALLY
HEAVY RAIN WITH THE SEVERE THUNDERSTORMS...BUT NOT WIDESPREAD
ENOUGH TO JUSTIFY THE CONTINUATION OF THE FLOOD WATCH.

SEVERE WEATHER WILL BE PROBLEM THIS EVENING...BUT FAIR WEATHER
SUNDAY AND BEYOND AS HIGH PRESSURE BUILDS IN AT ALL LEVELS FOR THE
WEEK.

MARINE: WILL LET CURRENT FORECAST RIDE AS LITTLE TIME TO LOOK AT
ANYTHING. SCEC CRITERIA MAY BE MET SUNDAY...AS PER CURRENT FORECAST.

PRELIM NUMBERS:
TPA 62/76/52/76 1000
FMY 66/81/55/80 4000

.TBW...FIRE WX WATCH SUNDAY FLZ039-042>043-052-056>057-061...AND
       INTERIOR FLZ048>049.

ALSHEIMER

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 31, 1:46 PM EST	Severe Thunderstorm Warning	TBW	Hillsborough, Pasco	29 min
Mar 31, 2:02 PM EST	Severe Thunderstorm Warning	TBW	Pinellas	28 min
Mar 31, 2:22 PM EST	Severe Thunderstorm Warning	TBW	Hillsborough	38 min
Mar 31, 2:27 PM EST	Severe Thunderstorm Warning	TBW	Polk	33 min
Mar 31, 3:01 PM EST	Severe Thunderstorm Warning	TBW	Hillsborough, Polk	29 min
Mar 31, 3:31 PM EST	Severe Thunderstorm Warning	TBW	Polk	44 min
Mar 31, 5:18 PM EST	Severe Thunderstorm Warning	TBW	Manatee, Sarasota	57 min
Mar 31, 6:27 PM EST	Severe Thunderstorm Warning	TBW	Sarasota	48 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; radar from the NEXRAD Level II archive.