Alert archive / Florida / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 22, NWS Tampa Bay, FL

April 28, 1999Polk County, Florida

NWS Tampa Bay, FL issued this severe thunderstorm warning at Apr 28, 1999, 4:31 PM EDT for Polk County, Florida. It was in force for 29 min. 3 reports 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
Apr 28, 1999, 4:31 PM EDT (20:31 UTC)
Expired
Apr 28, 1999, 5:00 PM EDT
In force
29 min
Issued by
NWS Tampa Bay, FL
Area
Whole counties

County Polk County, FL

What was reported inside it

TimeReportWhereRemark
Apr 28, 4:45 PM EDTHail 1.75Lakeland, FLGolfball sized hail was reported by a Skywarn spotter near the intersection of State Road 37 and County Road 540A.
Apr 28, 4:45 PM EDTThunderstorm WindLakeland, FLSkywarn spotters reported that the roofs of a few homes and commercial buildings incurred damage, while several commercial signs, trees and large branches were downed by thunderstorm winds near the intersection of State Road 37 and Lake Mirium Drive.
Apr 28, 4:48 PM EDTHail 1.75Lakeland, FLThe public reported golfball sized hail through at Hardin Boulevard near U.S. Highway 92 in Lakeland through Bay News Nine Cable Television.

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, 8.5 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 1999-04-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1203 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 1999-04-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 0 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
1203 J/kg
Mixed-layer CIN
-41 J/kg
Mixed-layer LCL
869 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
0 m²/s²
0-3 km storm-relative helicity
12 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 Apr 28, 2:52 PM EDT, 1 hour 39 minutes earlier.

Area forecast discussion, Apr 28, 2:52 PM EDT, 1 hour 39 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY-RUSKIN FL
252 PM EDT WED APR 28 1999

CURRENTLY NUMEROUS OUTFLOW BNDRYS NOTED ON SATL LOOP COMBINING WITH
SUFFICIENT MSTR AND INSTABILITY PWS 1.5 AND LIS -8 IS RESULTING
IN A LARGE AREA OF SHOWERS AND THUNDERSTORMS OVER MY INTERIOR ZONES
FROM LAKE PLACID NORTH TO HAINES CITY. IN ADDITION LARGE CLUSTERS OF
TSTMS ONGOING OVER THE NERN GULF WATERS. AS THE AFTERNOON CONTINUES
EXPECT TO SEE THE BEST AREAL COVERAGE OF STORMS TO CONTINUE OVER MY
INTERIOR ZONES...AND WOULD SUGGEST AT LEAST GOOD CHANCE CATEGORY
MENTION INTO THE EARLY EVENING HOURS. AS FOR MY COASTAL ZONES OUTFLOW
BNDRYS FROM GULF ACTIVITY IN CONJUNCTION WITH WCSB BNDRY MAY HELP TO
FIRE OFF CONVECTION ALONG THE IMMEDIATE COASTAL LOCATIONS LATER THIS
AFTERNOON AND WOULD RECOMMEND AT LEAST CHANCE CATEGORY POPS FOR THE
EVENING HOURS.

FOR TONIGHT...ALL CONVECTION SHOULD BEGIN TO WIND DOWN AFTER SUNSET
WITH LOSS OF SFC HTG AND WITH NVA MOVING INTO THE FA ON BACK SIDE OF
WEAK SHORT WAVE TROUGH MOVG EWD. SKIES SHOULD BECOME PARTLY CLOUDY
LATE TONIGHT AND WITH ADDED GROUND MOISTURE FROM THIS AFTERNOONS
PRECIP WILL LIKELY SEE AREAS OF FOG AND LOW CLOUDS DEVELOP AND
MENTION IN ZONES LOOKS IN ORDER.

FCST...HIGH AMPLIFIED PATTERN WITH OMEGA TYPE BLOCK OVER THE CENTRAL
U.S. WILL CONTINUE THRU THIS FCST CYCLE. ALL SHORT RANGE MODELS ARE
IN RELATIVELY GOOD AGREEMENT WITH THIS SCENARIO THRU 36 HRS...THEN
SOME SUBTLE DIFFERENCES ARE NOTED. CLOSED LOW OVER THE SW U.S. WILL
AMPLIFY SOME WHILE CLOSED LOW OVER THE UPR MS VALLEY MOVES SEWD WITH
ENERGY FROM CANADIAN MARITIMES CLOSED LOW DROPPING SWWD INTO THIS
LOW AND FORMING A CLOSED LOW OVER THE SERN GULF STATES VCNTY SC/GA
BORDER BY 12Z ON FRIDAY WITH A WEAK SFC REFLECTION EAST OF KJAX.
AVN/NGM AGREE ON THIS WHILE ETA KEEPS THIS TROUGH MORE OPENED UP AND
MOVES IT FURTHER EAST. WITH THE OMEGA BLOCKING TYPE PATTERN ALREADY
IN PLACE I CANT SEE WHY ETA WOULD BE SO PROGRESSIVE THUS WILL LEAN
TOWARD AVN/NGM SOLUTION IN THIS PACKAGE. WITH LITTLE OVERALL CHANGES
TO STABILITY OR MSTR PARAMETERS...THE THREAT OF SHOWERS AND TSTMS
WILL CONTINUE ON THURSDAY WITH HIGHEST POPS CONTINUING TO RESIDE OVER
MY INTERIOR ZONES WHERE E/W COAST SEA BREEZE AND OUTFLOW BNDRY
COLLISION TAKE PLACE. AS FOR TEMPS PREFER WARMER LOOKING FAN MINS TO
ACCOUNT FOR LIGHT WESTERLY FLOW OFF THE GULF...AND BLEND OF FAN/FWC
WITH MAXS.

EXTENDED...ON FRIDAY THE WEATHER MAY BECOME VERY INTERESTING ACRS MY
NRN INTO N-CENTRAL FA AS CLOSED UPR AND SFC LOWS WITH TRAILING FRONT
BEGINS TO AFFECT THE REGION. ATTM SOME STRONG TSTMS MAY BE POSSIBLE
AS COLD POOL ALOFT WITH UPR LOW WORKS IT WAY SOUTH INTO THE FA. IN
ADDITION COOLER TEMPS ARE EXPECTED DUE TO CLOUDS AND PRECIP.

MARINE...CONTINUED SOUTHWEST TO WESTERLY FLOW AROUND 10 KNOTS SHOULD
DO IT THROUGH THURSDAY WITH PM SEA BREEZE DVLPG. NO HIGHLIGHTS ARE
NEEDED.

TPA BB 071/086 070/082 064 57343
FMY BB 070/088 070/085 066 57343
LAL TT 070/090 069/086 065 57564

MCMICHAEL

In the hours before

Special weather statement, Apr 28, 11:02 AM EDT, 5 hours 29 minutes before
FLZ039-042-043-048>052-055>057-060>062-065-282330-

WEST CENTRAL AND SOUTHWEST FLORIDA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
1102 AM EDT WED APR 28 1999

...SCATTERED THUNDERSTORMS THIS AFTERNOON AND EARLY EVENING SOME
   POSSIBLY STRONG...

A WEAK DISTURBANCE IN THE UPPER LEVELS OF THE ATMOSPHERE ALONG WITH
SUFFICIENT MOISTURE...INSTABILITY AND SEA BREEZE BOUNDARY COLLISIONS
WILL ALL AID IN THE DEVELOPMENT OF SCATTERED SHOWERS AND THUNDER-
STORMS THIS AFTERNOON. SHOWERS AND THUNDERSTORMS WILL INITIALLY BEGIN
TO FORM ALONG THE WEST COAST SEA BREEZE EARLY THIS AFTERNOON...THEN
MOVE TOWARD THE INTERIOR PENINSULA DURING THE MID AND LATE AFTERNOON
HOURS WHERE THE BEST AREAL COVERAGE AND INTENSITY OF STORMS WILL
RESIDE.

AT THE PRESENT TIME LOCATIONS BETWEEN BUSHNELL AND ARCADIA AND
EAST TO SEBRING AND LAKE OKEECHOBEE WILL HAVE THE GREATEST THREAT
OF STORMS THIS AFTERNOON. THE PRIMARY THREAT FROM THE THUNDERSTORMS
THIS AFTERNOON WILL BE IN THE FORM OF LOCALLY HEAVY RAINS...FREQUENT
DEADLY LIGHTNING STRIKES...STRONG GUSTY WINDS TO 40 MPH AND HAIL.

ALL RESIDENTS OF WEST CENTRAL AND SOUTHWEST FLORIDA PLANNING ANY
OUTDOOR ACTIVITIES THIS AFTERNOON SHOULD BE ALERT TO RAPIDLY
CHANGING WEATHER CONDITIONS. IF THREATENING WEATHER APPROACHES YOUR
LOCATION...MOVE INDOORS IMMEDIATELY. SKYWARN STORM SPOTTERS AND
EMERGENCY MANAGEMENT OFFICIALS ARE ASKED TO RELAY ANY REPORTS OF
ADVERSE WEATHER TO THE NATIONAL WEATHER SERVICE OFFICE HERE IN
RUSKIN FLORIDA.

MCMICHAEL
Local storm report, Apr 28, 11:29 AM EDT, 5 hours 2 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE OFFICE TAMPA BAY AREA - RUSKIN FLORIDA
1129 AM EDT WED APR 28 1999

TIME(EDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

545  PM    FORT BASINGER             FL   0.75 INCH HAIL
04/27/99   HIGHLANDS                      REPORTED BY SKYWARN STORM
                                          SPOTTER.
Local storm report, Apr 28, 11:39 AM EDT, 4 hours 52 minutes before
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Local storm report, Apr 28, 11:39 AM EDT, 4 hours 52 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

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

IssuedProductOfficeCountiesLasted
Apr 28, 3:16 PM EDTSevere Thunderstorm WarningTBWPolk44 min
Apr 28, 3:35 PM EDTSevere Thunderstorm WarningTBWDeSoto25 min
Apr 28, 4:07 PM EDTSevere Thunderstorm WarningTBWDeSoto23 min
Apr 28, 7:04 PM EDTSevere Thunderstorm WarningTBWHillsborough, Pinellas41 min
Apr 28, 7:10 PM EDTSevere Thunderstorm WarningTBWSumter35 min

Nearby

Severe Thunderstorm Warnings in Florida, 1999Every severe thunderstorm warning in 1999

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.