Alert archive / Florida / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 35, NWS Melbourne, FL

July 20, 2002Seminole County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Jul 20, 2002, 4:56 PM EDT for Seminole County, Florida. It was in force for 34 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
Jul 20, 2002, 4:56 PM EDT (20:56 UTC)
Expired
Jul 20, 2002, 5:30 PM EDT
In force
34 min
Issued by
NWS Melbourne, FL
Area
Whole counties

County Seminole County, FL

The radar

The Melbourne radar (KMLB), 88 km from the middle of the area, began a volume at 20:56 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

Tampa Bay, FL (KTBW), launched 12:00Z, 8.9 hours before the alert went out and 160 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 2002-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3682 joules per kilogram.LCLEL10008507005003002001001 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 2002-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -22 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
3682 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
586 m above ground
0-6 km bulk shear
4 kt
0-1 km storm-relative helicity
-22 m²/s²
0-3 km storm-relative helicity
20 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

493 
WUUS52 KMLB 202056
SVRMLB
FLC117-202130-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MELBOURNE FL
454 PM EDT SAT JUL 20 2002

THE NATIONAL WEATHER SERVICE IN MELBOURNE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN SEMINOLE COUNTY
  IN EAST CENTRAL FLORIDA

* UNTIL 530 PM EDT.

* AT 450 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  A SEVERE THUNDERSTORM OVER WEKIVA SPRINGS...  MOVING NORTHEAST AT  
  5 TO 10 MPH.

* THE SEVERE THUNDERSTORM WILL BE...
  NEAR WEKIVA SPRINGS...LAKE MARY AND ALTAMONTE SPRINGS. 

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS IN EXCESS OF 58 MILES AN
HOUR...DESTRUCTIVE HAIL...DEADLY LIGHTNING AND VERY HEAVY RAIN. IF
THE STORM APPROACHES YOU...MOVE TO AN INTERIOR ROOM ON THE LOWEST 
FLOOR. THIS STORM WILL ALSO EXCESSIVE LIGHTNING...MOVE INDOORS NOW.

$$

LAT...LON 2872 8142 2861 8135 2877 8116 2884 8136

VOLKMER

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 20, 2:45 PM EDTSpecial Marine WarningMLB105 min
Jul 20, 2:45 PM EDTSpecial Marine WarningMLB105 min
Jul 20, 2:51 PM EDTSevere Thunderstorm WarningMLBBrevard54 min
Jul 20, 3:50 PM EDTSevere Thunderstorm WarningMLBOrange, Osceola40 min
Jul 20, 4:27 PM EDTSevere Thunderstorm WarningMLBOrange, Osceola63 min
Jul 20, 5:52 PM EDTSevere Thunderstorm WarningMLBLake53 min

Nearby

Severe Thunderstorm Warnings in Florida, 2002Every severe thunderstorm warning in 2002

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.