Alert archive / Florida / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 39, NWS Tampa Bay, FL

February 28, 1998Citrus County, Florida

NWS Tampa Bay, FL issued this severe thunderstorm warning at Feb 28, 1998, 8:05 AM EST for Citrus County, Florida. It was in force for 60 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
Feb 28, 1998, 8:05 AM EST (13:05 UTC)
Expired
Feb 28, 1998, 9:05 AM EST
In force
60 min
Issued by
NWS Tampa Bay, FL
Area
Whole counties

County Citrus County, FL

The radar

The Tampa radar (KTBW), 128 km from the middle of the area, began a volume at 13:05 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
Feb 28, 8:24 AM ESTHail 0.75Crystal River, FL

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, 1.1 hours before the alert went out and 128 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 1998-02-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1297 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 1998-02-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 194 square meters per square second.19395878Sfc1 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
1297 J/kg
Mixed-layer CIN
-29 J/kg
Mixed-layer LCL
722 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
194 m²/s²
0-3 km storm-relative helicity
188 m²/s²
Significant tornado parameter
1.5
Supercell composite
10.6

Open this sounding in Storm Lab

The text

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

765 
WUUS1 KTBW 281306 RRA
SVRTBW
FLC017-GMZ850-281405-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
805 AM EST SAT FEB 28 1998

THE NATIONAL WEATHER SERVICE HAS ISSUED A...SEVERE THUNDERSTORM WARNING
EFFECTIVE UNTIL 905 AM EST FOR

...CITRUS COUNTY

...AND INCLUDING THE GULF WATERS FROM WACCASASSA BAY TO HOMOSASSA RIVER

DOPPLER RADAR INDICATED SEVERE THUNDERSTORMS NEAR CRYSTAL RIVER
AND CHASSAHOWITZKA SPRINGS MOVING EAST AT 30 MPH.

BY DEFINITION...SEVERE THUNDERSTORMS HAVE WINDS OF 58 MPH OR GREATER
AND/OR DIME SIZE HAIL OR LARGER. IF THIS STORM APPROACHES YOUR
AREA...GO INDOORS AND STAY UNTIL THE STORM PASSES.

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 Feb 28, 3:15 AM EST, 4 hours 50 minutes earlier.

Area forecast discussion, Feb 28, 3:15 AM EST, 4 hours 50 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY-RUSKIN, FL
315 AM EST SAT FEB 28 1998

A SHORT WAVE MOVING INTO THE PANHANDLE THIS MORNING IS ADDING FIRE TO
THE THUNDERSTORMS IN THE AREA.  THE SHORT WAVE WILL SWING NORTH INTO
THE APPALACHIANS THIS AFTERNOON...BUT NOT WITHOUT GIVING OUR FRONT A
LITTLE PUSH SOUTH AND EASTWARD.  THEN EXPECT THE FRONT TO STALL AGAIN
OVER NORTH FLORIDA.  WITH THE LONGWAVE TROUGH REMAINING WELL TO OUR
WEST...ALBEIT A FLATTER TROUGH...THROUGHOUT THE PERIOD I DO NOT SEE ANY
REASON TO PUSH THE FRONT THROUGH TOO RAPIDLY.  IN FACT I WOULD BE REAL
HAPPY TO SEE THE CURRENT ZONES CHANGED FOR SUNDAY TO READ MOSTLY
CLOUDY WITH A SLIGHT CHANCE OR CHANCE OF THUNDERSTORMS.

THE ETA IS AGAIN MY MODEL OF CHOICE...BUT LIKE ALL OF THE MODELS I THINK
IT IS IN TOO MUCH OF A HURRY TO PUSH THE FRONT OUT.  THERE IS A SECONDARY
FRONT APPROACHING THE MISSISSIPPI VALLEY THIS MORNING WHICH MAY GIVE
OUR FRONT A LITTLE PUSH...BUT NOT ENOUGH TO PUSH IT INTO THE ATLANTIC.  IT
IS HARD TO ARGUE WHEN ALL MODELS AGREE ON SOMETHING BUT THE BUILDING
RIDGE IN THE GULF...WHICH I AM PRESUMING IS PUSHING OUT OUR FRONT JUST
LOOKS A LITTLE FISHY.  AGAIN MY ARGUMENT IS THAT THE BASE OF THE TROUGH
IS WELL WEST OF OUR AREA AND THE AVN DROPS ANOTHER SHORT WAVE DOWN
THE BACKSIDE OF THE TROUGH 60 TO 72 HOURS OUT CAUSING IT TO RETROGRADE
BACK TOWARDS TEXAS.

WITH INSTABILITY WELL ENTRENCHED AND EVEN MORE RICH LOW LEVEL AIR
ADVECTING IN I WOULD NOT BE SURPRISED TO SEE SOME THUNDER AROUND THIS
AFTERNOON.  I WAS AWOKEN BY A THUNDER AROUND NOON TODAY AT MY HOUSE
AND CONDITIONS ARE A LITTLE BETTER TODAY.  FWC AND FAN GUIDANCE ARE
FINALLY LOOKING PRETTY CLOSE I HAVE NO PROBLEM WITH EITHER...WHICH
WOULD INDICATE THAT THE HIGH TEMP WE HAVE FOR TODAY IN THE ZONES MAY
BE A LITTLE ON THE LOW SIDE...BUT NOT OUT OF THE BALLPARK.  POPS MAY BE A
LITTLE LOW IN OUR FAR NORTHERN COUNTIES FOR TODAY...CENTRAL AND SOUTH
LOOK OK.  THANKS FOR YOUR THOUGHTS MLB.

SOBIEN

In the hours before

Special weather statement, Feb 28, 6:00 AM EST, 2 hours 5 minutes before
FLZ039-042-043-048>052-055>057-060>062-065-GMZ830-850-853-870-873-2802300-

WEST CENTRAL AND SOUTHWEST FLORIDA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
600 AM EST SAT FEB 28 1998

...ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS WEST CENTRAL AND
   SOUTHWEST FLORIDA SATURDAY NIGHT...

...RIVER FLOOD WARNINGS REMAIN IN EFFECT FOR THE WITHLACOOCHEE...
   MYAKKA...AND PEACE RIVERS...AND CYPRESS CREEK...

...LOCALLY HEAVY RAINFALL POSSIBLE THIS AFTERNOON AND TONIGHT
   PORTIONS OF WEST CENTRAL FLORIDA...

A VERY SLOW MOVING FRONTAL BOUNDARY STRETCHING ACROSS THE FLORIDA
BIG BEND AREA SOUTHWEST INTO THE GULF OF MEXICO THIS MORNING WILL
DRIFT INTO NORTH CENTRAL FLORIDA BY SUNDAY MORNING.  A STRONG UPPER
LEVEL JET AND A SUFFICIENTLY UNSTABLE ATMOSPHERE OVER FLORIDA WILL
LEAD TO THUNDERSTORMS THAT WILL DEVELOP ALONG THE FRONT AND JUST
AHEAD OF THE FRONT.  THE AREAS OF RAIN THAT DO FORM WILL
MOVE NEARLY PARALLEL TO THE FRONT OVER THE SAME AREAS. THIS WOULD
CAUSE LOCALLY HEAVY RAINFALL AMOUNTS TO BE POSSIBLE. GIVEN
ALREADY SATURATED GROUND AND HIGH RIVER LEVELS...THE PREMISE FOR
WORSENED RIVER FLOODING AND FLOODING OF LOW LYING AND FLOOD PRONE
AREAS EXISTS TODAY AND TONIGHT.

WIDESPREAD SEVERE WEATHER IS NOT EXPECTED WITH THIS EVENT BUT THE
ATMOSPHERE WILL BE UNSTABLE ENOUGH AND WINDS ALOFT STRONG ENOUGH
THAT AN ISOLATED SEVERE THUNDERSTORM MAY BE POSSIBLE.  IN ADDITION DRY
AIR ALOFT MAY ENHANCE THUNDERSTORMS SOMEWHAT.  THE MAIN THREAT WITH
THESE STORMS WILL BE STRONG WINDS AND LARGE HAIL.

RESIDENTS LIVING IN THESE FLOOD PRONE AREAS SHOULD REMAIN ALERT TO
THE POSSIBILITY OF FLOODING IF THE HEAVY RAINS DEVELOP.

SKYWARN UNITS SHOULD BE AWARE THAT THEY MAY BE NEEDED LATER TODAY
AND TONIGHT...IF SEVERE THUNDERSTORMS DO DEVELOP.

FOR THE LATEST WARNINGS AND STATEMENTS ON THUNDERSTORMS OR RIVER
FLOODING...LISTEN TO NOAA WEATHER RADIO OR COMMERCIAL RADIO AND TV.

SOBIEN
Special weather statement, Feb 28, 6:36 AM EST, 1 hour 29 minutes before
FLZ039-042-043-048>052-055>057-060>062-065-GMZ830-850-853-870-873-2802300-

WEST CENTRAL AND SOUTHWEST FLORIDA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
600 AM EST SAT FEB 28 1998

...ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS WEST CENTRAL AND
   SOUTHWEST FLORIDA SATURDAY NIGHT...

...RIVER FLOOD WARNINGS REMAIN IN EFFECT FOR THE WITHLACOOCHEE...
   MYAKKA...AND PEACE RIVERS...AND CYPRESS CREEK...

...LOCALLY HEAVY RAINFALL POSSIBLE THIS AFTERNOON AND TONIGHT
   PORTIONS OF WEST CENTRAL FLORIDA...

A VERY SLOW MOVING FRONTAL BOUNDARY STRETCHING ACROSS THE FLORIDA
BIG BEND AREA SOUTHWEST INTO THE GULF OF MEXICO THIS MORNING WILL
DRIFT INTO NORTH CENTRAL FLORIDA BY SUNDAY MORNING.  A STRONG UPPER
LEVEL JET AND A SUFFICIENTLY UNSTABLE ATMOSPHERE OVER FLORIDA WILL
LEAD TO THUNDERSTORMS THAT WILL DEVELOP ALONG THE FRONT AND JUST
AHEAD OF THE FRONT.  THE AREAS OF RAIN THAT DO FORM WILL
MOVE NEARLY PARALLEL TO THE FRONT OVER THE SAME AREAS. THIS WOULD
CAUSE LOCALLY HEAVY RAINFALL AMOUNTS TO BE POSSIBLE. GIVEN
ALREADY SATURATED GROUND AND HIGH RIVER LEVELS...THE PREMISE FOR
WORSENED RIVER FLOODING AND FLOODING OF LOW LYING AND FLOOD PRONE
AREAS EXISTS TODAY AND TONIGHT.

WIDESPREAD SEVERE WEATHER IS NOT EXPECTED WITH THIS EVENT BUT THE
ATMOSPHERE WILL BE UNSTABLE ENOUGH AND WINDS ALOFT STRONG ENOUGH
THAT AN ISOLATED SEVERE THUNDERSTORM MAY BE POSSIBLE.  IN ADDITION DRY
AIR ALOFT MAY ENHANCE THUNDERSTORMS SOMEWHAT.  THE MAIN THREAT WITH
THESE STORMS WILL BE STRONG WINDS AND LARGE HAIL.

RESIDENTS LIVING IN THESE FLOOD PRONE AREAS SHOULD REMAIN ALERT TO
THE POSSIBILITY OF FLOODING IF THE HEAVY RAINS DEVELOP.

SKYWARN UNITS &SHOULD BE AWARE THAT THEY MAY BE NEEDED LATER TODAY
AND TONIGHT...IF SEVERE THUNDERSTORMS DO DEVELOP.

FOR THE LATEST WARNINGS AND STATEMENTS ON THUNDERSTORMS OR RIVER
FLOODING...LISTEN TO NOAA WEATHER RADIO OR COMMERCIAL RADIO AND TV.

SOBIEN

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 28, 9:20 AM ESTSevere Thunderstorm WarningTBWPasco60 min
Feb 28, 10:22 AM ESTSevere Thunderstorm WarningTBWPasco48 min
Feb 28, 11:45 AM ESTSevere Thunderstorm WarningTBWPolk65 min
Feb 28, 12:10 PM ESTSevere Thunderstorm WarningTBWHillsborough, Manatee65 min

Nearby

Severe Thunderstorm Warnings in Florida, 1998Every severe thunderstorm warning in 1998

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.