Alert archive / Florida / Severe Thunderstorm Warnings in 2004

Severe Thunderstorm Warning 95, NWS Miami, FL

August 29, 2004Palm Beach County, Florida

NWS Miami, FL issued this severe thunderstorm warning at Aug 29, 2004, 8:48 PM EDT for Palm Beach County, Florida. It was in force for 57 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 29, 2004, 8:48 PM EDT (00:48 UTC)
Expired
Aug 29, 2004, 9:45 PM EDT
In force
57 min
Issued by
NWS Miami, FL
Area
Counties, with a storm outline in the text

County Palm Beach County, FL

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Miami, FL (KMFL), launched 00:00Z, 0.8 hours before the alert went out and 116 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, Miami, FL at 00:00Z on 2004-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1770 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, Miami, FL at 00:00Z on 2004-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 5 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
1770 J/kg
Mixed-layer CIN
-21 J/kg
Mixed-layer LCL
1070 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
5 m²/s²
0-3 km storm-relative helicity
15 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.

000 
WUUS52 KMFL 300048 CCA
SVRMIA
FLC099-300145-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING...CORRECTION 
NATIONAL WEATHER SERVICE MIAMI FL
844 PM EDT SUN AUG 29 2004

LOCATION CORRECTION 

THE NATIONAL WEATHER SERVICE IN MIAMI HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN PALM BEACH COUNTY IN SOUTH FLORIDA.

* UNTIL 945 PM EDT

* AT 844 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
STORM CAPABLE OF PRODUCING DIME SIZE HAIL JUST SOUTH OF PAHOKEE     
...MOVING NORTHEAST AT 20 MPH.

* THE STORM WILL AFFECT...
  PAHOKEE BY 845 PM EDT.
  CANAL POINT BY 855 PM EDT.

SEVERE THUNDERSTORMS CAN PRODUCE DAMAGING WINDS IN EXCESS OF 60 
MPH...LARGE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAINFALL. STAY 
INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.

LAT...LON 2676 8073 2673 8070 2688 8056 2691 8061

$$

JR

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 Miami, FL wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 29, 1:15 PM EDT, 7 hours 33 minutes earlier.

Area forecast discussion, Aug 29, 1:15 PM EDT, 7 hours 33 minutes before
SOUTH FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
115 PM EDT SUN AUG 29 2004

.DISCUSSION...THE PROBLEM WE HAVE IN THIS CYCLE IS HURRICANE
FRANCES. BECAUSE OF THE LATEST TPC/HPC GUIDANCE WHICH WAS FROM 15UTC
HAVE HAD TO INCREASE THE WINDS IN THE FRIDAY THROUGH THE WEEKEND
PERIOD. WE ARE LIMITED TO 30 KNOTS IN THESE PERIODS FOR SUSTAINED
WINDS.  HAVE ALSO INCREASED THE RAIN PROBABILITY BECAUSE OF THE DAY
5-7 FRANCES TRACK.  UNFORTUNATELY AT THIS TIME THESE GRIDDED
CONDITIONS SHOULD STILL BE VIEWED AS UNCERTAIN.  OR TO A CERTAIN
EXTENT CAN BE IGNORED SINCE A RELATIVELY LITTLE ERROR IN FRANCES
WILL GIVE A BIG ERROR IN WHAT WE HAVE PUT IN THE GRIDS.  WHEN THE
DATA FROM THE RECON AND NOAA PLANES GET INTO THE 30/OOUTC MODEL RUNS
WE SHOULD HAVE A BETTER INDICATION OF THE STRENGTH OF THE UPPER
ATLANTIC RIDGE AND THE POSSIBLE TRACK OF THE STORM.

IN THE TIME UNTIL THE APPROACH OF FRANCES OR BETWEEN NOW AND FRIDAY
WE SHOULD SEE LITTLE IN DAY TO DAY CHANGES.  WE SHOULD REMAIN MAINLY
IN A VERY WEAK SURFACE PRESSURE PATTERN WHICH WILL PROBABLY BE MORE
OF A TROUGH THAN A RIDGE.  SO WE SHOULD CONTINUE WITH LITTLE CHANGE
UNTIL THE HURRICANE STARTS ITS IMPACT.

&&

.MARINE...BOATING SHOULD BE GOOD THROUGH THE WEEK.  THEN BY LATE
WEEK REGARDLESS OF THE EVENTUAL FRANCES TRACK WE SHOULD SEE
DETERIORATING BOATING ESPECIALLY IN THE ATLANTIC.

&&

.FIRE WEATHER...NO CONCERNS.

&&

.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 76 91 77 91 / 10 40 20 30
FORT LAUDERDALE 78 91 79 90 / 10 40 20 30
MIAMI           78 91 79 91 / 10 40 20 30
NAPLES          77 90 75 91 / 05 30 20 20
&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.

&&
Hazardous weather outlook, Aug 29, 10:15 AM EDT, 10 hours 33 minutes before
HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE MIAMI FL
1015 AM EDT SUN AUG 29 2004

FLZ063-066>075-292200-
BROWARD METROPOLITAN-DADE METROPOLITAN-EASTERN COLLIER-GLADES-HENDRY-
MAINLAND MONROE-PALM BEACH EASTERN-PALM BEACH WESTERN-
WESTERN BROWARD-WESTERN COLLIER-WESTERN DADE-
1015 AM EDT SUN AUG 29 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTH FLORIDA.

.DAY ONE...TODAY

...SCATTERED AFTERNOON THUNDERSTORMS EAST COAST AND INTERIOR...

SCATTERED THUNDERSTORMS WILL DEVELOP THIS AFTERNOON AND WILL FAVOR
THE INTERIOR AND ATLANTIC COAST PORTIONS OF SOUTH FLORIDA.
LIGHTNING, LOCAL DOWNPOURS, AND GUSTY WINDS ARE POSSIBLE.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

HURRICANE FRANCES IS FORECAST TO MOVE WEST-NORTHWEST INTO THE
CENTRAL BAHAMAS BY LATE THURSDAY. INTERESTS IN SOUTH FLORIDA SHOULD
MONITOR THE LATEST ADVISORIES ON THIS HURRICANE OVER THE NEXT
SEVERAL DAYS AS FRANCES APPOACHES THE BAHAMAS.

COMPREHENSIVE WEATHER FORECASTS, GRAPHICS, AND PREPAREDNESS
INFORMATION CAN BE FOUND ON OUR WEB SITE AT MIAMIWEATHER.INFO.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY.

HANDEL

In the hours before

Special weather statement, Aug 29, 8:31 PM EDT, 17 minutes before
SIGNIFICANT WEATHER ALERT
NATIONAL WEATHER SERVICE MIAMI FL
831 PM EDT SUN AUG 29 2004

FLZ067-300130-
PALM BEACH WESTERN-
831 PM EDT SUN AUG 29 2004

STRONG THUNDERSTORMS HAVE MOVED INTO WESTERN PALM BEACH COUNTY AND
WILL MOVE NORTHEAST AT 10 MPH. THESES THUNDERSTORMS WILL CROSS U S
27 AND MOVE INTO OKEELANTA AND BELLE GLADE AREA OVER THE NEXT HALF
HOUR. VERY HEAVY RAIN AND ALMOST CONTINOUS LIGHTNING WILL ACCOMPANY
THESE THUNDERSTORMS.

EXPECT FREQUENT LIGHTNING...GUSTY WINDS TO 50 MPH...PEA-SIZED HAIL...
AND TORRENTIAL DOWNPOURS CAN BE EXPECTED. A WARNING WILL BE ISSUED
IF THIS THUNDERSTORM ACTIVITY STRENGTHENS.

THE MAIN IMPACT WILL BE FREQUENT LIGHTNING. TREES AND OPEN SHELTERS
FOUND ON BEACHES OR GOLF COURSES OFFER NO PROTECTION. GET INDOORS
NOW

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 29, 8:44 PM EDTSevere Thunderstorm WarningMFLPalm Beach61 min
Aug 29, 8:46 PM EDTSpecial Marine WarningMFL59 min

Nearby

Severe Thunderstorm Warnings in Florida, 2004Every severe thunderstorm warning in 2004

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.