Alert archive / Florida / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 21, NWS Tampa Bay, FL

March 31, 2001Polk County, Florida

NWS Tampa Bay, FL issued this severe thunderstorm warning at Mar 31, 2001, 2:27 PM EST for Polk County, Florida. It was in force for 33 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
Mar 31, 2001, 2:27 PM EST (19:27 UTC)
Expired
Mar 31, 2001, 3:00 PM EST
In force
33 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 19:30 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.

What was reported inside it

TimeReportWhereRemark
Mar 31, 2:38 PM ESTHail 1.75Polk City, FLGolfball to dime sized hail was reported by Skywarn Spotters from Haines City to Polk City in northern Polk county.

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

Cape Canaveral, FL (KXMR), launched 12:00Z, 7.5 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-pSkew-T log-p diagram, Cape Canaveral, FL at 12:00Z on 2001-03-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1036 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Cape Canaveral, FL at 12:00Z on 2001-03-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 22 square meters per square second.1939587897117Sfc1 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
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 311927
SVRTBW
FLC105-312000-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
227 PM EST SAT MAR 31 2001

THE NATIONAL WEATHER SERVICE IN RUSKIN HAS ISSUED A

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

* UNTIL 300 PM EST.

* AT 227 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM WITH LARGE HAIL...OVER NORTHWESTERYN POLK
  COUNTY...MOVING NORTHEAST AT 35 MPH.

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

$$

LAT...LON 2825 8200 2808 8192 2825 8140 2845 8150

NNNN

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 31, 1:46 PM ESTSevere Thunderstorm WarningTBWHillsborough, Pasco29 min
Mar 31, 2:02 PM ESTSevere Thunderstorm WarningTBWPinellas28 min
Mar 31, 2:22 PM ESTSevere Thunderstorm WarningTBWHillsborough38 min
Mar 31, 3:01 PM ESTSevere Thunderstorm WarningTBWHillsborough, Polk29 min
Mar 31, 3:31 PM ESTSevere Thunderstorm WarningTBWPolk44 min
Mar 31, 4:15 PM ESTSevere Thunderstorm WarningTBWPolk25 min
Mar 31, 5:18 PM ESTSevere Thunderstorm WarningTBWManatee, Sarasota57 min
Mar 31, 6:27 PM ESTSevere Thunderstorm WarningTBWSarasota48 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; radar from the NEXRAD Level II archive.