Alert archive / Florida / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 91, NWS Tampa Bay, FL
NWS Tampa Bay, FL issued this severe thunderstorm warning at May 21, 1999, 3:30 PM EDT for Manatee County, Sarasota County, Florida. It was in force for 35 min. 2 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
- May 21, 1999, 3:30 PM EDT (19:30 UTC)
- Expired
- May 21, 1999, 4:05 PM EDT
- In force
- 35 min
- Issued by
- NWS Tampa Bay, FL
- Area
- Whole counties
Counties Manatee County, FL, Sarasota County, FL
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 21, 3:50 PM EDT | Hail 1.75 | Bradenton, FL | Golfball sized hail was reported in the Lakewood Ranch Estates along State Road 70 two miles east of Interstate 75 by the Manatee county sheriff department. |
| May 21, 4:15 PM EDT | Hail 0.75 | Myakka City, FL | Dime sized hail was reported at the Pacific Tomato Farm along State Road 70 by the Myakka City Grocery Store. |
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, 7.5 hours before the alert went out and 42 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.
- Mixed-layer CAPE
- 1033 J/kg
- Mixed-layer CIN
- -65 J/kg
- Mixed-layer LCL
- 947 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 36 m²/s²
- 0-3 km storm-relative helicity
- 76 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
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 May 21, 3:00 PM EDT, 30 minutes earlier.
Area forecast discussion, May 21, 3:00 PM EDT, 30 minutes before
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAMPA BAY-RUSKIN FL 300 PM EDT FRI MAY 21 1999 ECSB MAKING GOOD PROGRESS INTO OUR EASTERN COUNTIES AND SETTING OFF TSRA ACROSS POLK CO. MEANWHILE...WCSB ALSO SETTING OFF QUITE A FEW TSRA ALONG THE WEST COAST. AS I TYPE...TSRA CONTINUES OVERHEAD AT THE OFFICE. EXPECT SHOWERS TO CONTINUE WITH SOME SEVERE ACTIVITY POSSIBLE AS SOON AS SEABREEZES COLLIDE. AS JAX POINTED OUT...MOS WAS AND CONTINUES TO BE STINGY WITH POPS ACROSS THE AREA WHICH DOESNT SEEM TO REPRESENT WHAT IS ACTUALLY HAPPENENING. THE 50H VORT LOBE...WHICH IS RIGHT OVER US THIS AFTERNOON...IS FORECAST TO SLIDE SOUTHWARD INTO MIA CWA BY TOMORROW. THIS MAY DECREASE COVERAGE ACROSS THE NORTH AND CENTRAL...BUT THINK CHANCE POPS WOULD STILL BE IN ORDER. SFC HIGH IS EXPECTED TO BE IN THE ATLANTIC WITH A LIGHT EAST/SOUTHEAST FLOW...SO WCSB SHOULD STILL BE AROUND TO INTERACT WITH ECSB. STILL KEEPING ONE EYE ON CARIBBEAN DISTURBANCE...BUT EACH OF THE LATER MODEL RUNS CONTINUE TO PUSH THE SYSTEM FARTHER EAST AND IF THE TREND CONTINUES...WILL NOT AFFECT US. SG/67
In the hours before
Special weather statement, May 21, 1:30 PM EDT, 2 hours before
FLZ039-042-043-048>052-055>057-060>062-065-220000- WEST CENTRAL AND SOUTHWEST FLORIDA HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL 130 PM EDT FRI MAY 21 1999 ...STRONG TO SEVERE THUNDERSTORMS POSSIBLE THIS AFTERNOON AND EVENING... THE PRESENCE OF AN UPPER LEVEL DISTURBANCE AND PLENTY OF LOW LEVEL MOISTURE WILL COMBINE WITH THE EAST COAST SEA BREEZE TO PRODUCE SCATTERD STRONG TO SEVERE THUNDERSTORMS ACROSS MUCH OF THE REGION THROUGH THE REMAINDER OF AFTERNOON AND INTO THE EVENING TONIGHT. EAST TO SOUTHEAST FLOW WILL BRING THE EAST COAST SEA BREEZE ACROSS THE STATE AND WILL INTERACT WITH THE WEST COAST SEA BREEZE NEAR THE WEST COAST. DUE TO UNUSUALLY COLD AIR ALOFT...ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL FOR LARGE HAIL AND DAMAGING DOWNBURST WINDS OF 45 MPH OR GREATER. THE BEST CHANCES FOR THUNDERSTORMS THIS AFTERNOON WILL BE ALONG AND SOUTH OF A TAMPA TO LAKELAND LINE...WHERE MOISTURE AND INSTABILITY REMAIN A BIT HIGHER. HOWEVER...OTHER THUNDERSTORMS ARE POSSIBLE ALONG ALL COASTAL COUNTIES THROUGHOUT THE REMAINDER OF THE DAY. ALL RESIDENTS PLANNING ANY OUTDOOR ACTIVITIES SHOULD REMAIN ALERT TO RAPIDLY CHANGING WEATHER CONDITIONS. REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO THE STORM TO BE STRUCK BY LIGHTNING ...SO MOVE INDOORS IMMEDIATELY. GARRARD
Special weather statement, May 21, 1:30 PM EDT, 2 hours before
FLZ039-042-043-048>052-055>057-060>062-065-220000- WEST CENTRAL AND SOUTHWEST FLORIDA HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL 130 PM EDT FRI MAY 21 1999 ...STRONG TO SEVERE THUNDERSTORMS POSSIBLE THIS AFTERNOON AND EVENING... THE PRESENCE OF AN UPPER LEVEL DISTURBANCE AND PLENTY OF LOW LEVEL MOISTURE WILL COMBINE WITH THE EAST COAST SEA BREEZE TO PRODUCE SCATTERD STRONG TO SEVERE THUNDERSTORMS ACROSS MUCH OF THE REGION THROUGH THE REMAINDER OF AFTERNOON AND INTO THE EVENING TONIGHT. EAST TO SOUTHEAST FLOW WILL BRING THE EAST COAST SEA BREEZE ACROSS THE STATE AND WILL INTERACT WITH THE WEST COAST SEA BREEZE NEAR THE WEST COAST. DUE TO UNUSUALLY COLD AIR ALOFT...ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL FOR LARGE HAIL AND DAMAGING DOWNBURST WINDS OF 45 MPH OR GREATER. THE BEST CHANCES FOR THUNDERSTORMS THIS AFTERNOON WILL BE ALONG AND SOUTH OF A TAMPA TO LAKELAND LINE...WHERE MOISTURE AND INSTABILITY REMAIN A BIT HIGHER. HOWEVER...OTHER THUNDERSTORMS ARE POSSIBLE ALONG ALL COASTAL COUNTIES THROUGHOUT THE REMAINDER OF THE DAY. ALL RESIDENTS PLANNING ANY OUTDOOR ACTIVITIES SHOULD REMAIN ALERT TO RAPIDLY CHANGING WEATHER CONDITIONS. REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO THE STORM TO BE STRUCK BY LIGHTNING ...SO MOVE INDOORS IMMEDIATELY. GARRARD
The office that day
Everything else NWS Tampa Bay, FL issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 20, 8:08 PM EDT | Severe Thunderstorm Warning | TBW | Highlands | 32 min |
| May 20, 8:29 PM EDT | Severe Thunderstorm Warning | TBW | DeSoto | 31 min |
| May 21, 3:01 PM EDT | Severe Thunderstorm Warning | TBW | Manatee | 34 min |
| May 21, 3:30 PM EDT | Severe Thunderstorm Warning | TBW | Hillsborough | 35 min |
| May 21, 4:06 PM EDT | Severe Thunderstorm Warning | TBW | Hillsborough, Manatee | 29 min |
| May 21, 4:06 PM EDT | Severe Thunderstorm Warning | TBW | Pinellas | 29 min |
| May 21, 4:28 PM EDT | Severe Thunderstorm Warning | TBW | Sarasota | 32 min |
| May 21, 4:33 PM EDT | Severe Thunderstorm Warning | TBW | Hillsborough | 32 min |
| May 21, 4:33 PM EDT | Severe Thunderstorm Warning | TBW | Lee | 32 min |
| May 21, 4:49 PM EDT | Severe Thunderstorm Warning | TBW | Charlotte | 31 min |
| May 21, 4:58 PM EDT | Severe Thunderstorm Warning | TBW | DeSoto | 47 min |
| May 21, 5:15 PM EDT | Tornado Warning | TBW | DeSoto | 45 min |
| May 21, 5:25 PM EDT | Severe Thunderstorm Warning | TBW | Hardee | 50 min |
| May 21, 5:33 PM EDT | Severe Thunderstorm Warning | TBW | Polk | 57 min |
| May 21, 5:42 PM EDT | Severe Thunderstorm Warning | TBW | Pinellas | 33 min |
| May 21, 6:00 PM EDT | Severe Thunderstorm Warning | TBW | Sumter | 45 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.