Alert archive / Florida / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 142, NWS Miami, FL

September 4, 2012Palm Beach County, Florida

NWS Miami, FL issued this severe thunderstorm warning at Sep 4, 2012, 7:05 PM EDT for Palm Beach County, Florida. It was in force for 25 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
Sep 4, 2012, 7:05 PM EDT (23:05 UTC)
Expired
Sep 4, 2012, 7:30 PM EDT
In force
25 min
Issued by
NWS Miami, FL
Area
Storm-based polygon

County Palm Beach County, FL

The radar

The Miami radar (KAMX), 118 km from the middle of the area, began a volume at 23:07 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

Miami, FL (KMFL), launched 12:00Z, 11.1 hours before the alert went out and 93 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 12:00Z on 2012-09-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2198 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Miami, FL at 12:00Z on 2012-09-04The 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
2198 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
759 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
-5 m²/s²
0-3 km storm-relative helicity
61 m²/s²
Significant tornado parameter
0.5
Supercell composite
2.9

Open this sounding in Storm Lab

The text

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

687 
WUUS52 KMFL 042305
SVRMFL
FLC099-042330-
/O.NEW.KMFL.SV.W.0142.120904T2305Z-120904T2330Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MIAMI FL
705 PM EDT TUE SEP 4 2012

THE NATIONAL WEATHER SERVICE IN MIAMI HAS ISSUED A

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

* UNTIL 730 PM EDT

* AT 705 PM EDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH.  THIS STORM WAS LOCATED 8 MILES SOUTHWEST OF
  WELLINGTON...AND MOVING NORTHEAST AT 15 MPH.

* THE STORM WILL AFFECT...
  RURAL CENTRAL PALM BEACH COUNTY
  AND SURROUNDING COMMUNITIES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS IN EXCESS OF 58 MPH AND
OR LARGE HAIL. FREQUENT TO EXCESSIVE LIGHTNING AND HEAVY RAINFALL IS
ALSO POSSIBLE. IF THE STORM APPROACHES YOUR LOCATION, SEEK SHELTER IN
AN ENCLOSED BUILDING ON THE LOWEST FLOOR AND STAY AWAY FROM WINDOWS.

&&

LAT...LON 2680 8021 2663 8004 2647 8032 2659 8044
TIME...MOT...LOC 2306Z 230DEG 14KT 2657 8031

$$

AK
2 follow-up statements
911 
WWUS52 KMFL 042311
SVSMFL

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MIAMI FL
711 PM EDT TUE SEP 4 2012

FLC099-042330-
/O.CON.KMFL.SV.W.0142.000000T0000Z-120904T2330Z/
PALM BEACH FL-
711 PM EDT TUE SEP 4 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM EDT
FOR EAST CENTRAL PALM BEACH COUNTY...

AT 710 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING DESTRUCTIVE WINDS
IN EXCESS OF 70 MPH. THIS STORM WAS LOCATED 6 MILES SOUTH OF
WELLINGTON...MOVING NORTHEAST AT 20 MPH.

SEVERE THUNDERSTORMS CAN PRODUCE DAMAGING WINDS IN EXCESS OF 70
MPH...LARGE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAINFALL. FOR
YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR
HOME OR BUSINESS. THIS STORM HAS THE POTENTIAL TO CAUSE SERIOUS
INJURY AND SIGNIFICANT DAMAGE TO PROPERTY.

LAT...LON 2650 8029 2661 8041 2680 8021 2663 8004
TIME...MOT...LOC 2311Z 231DEG 18KT 2658 8028

$$

AK
227 
WWUS52 KMFL 042326
SVSMFL

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MIAMI FL
726 PM EDT TUE SEP 4 2012

FLC099-042337-
/O.EXP.KMFL.SV.W.0142.000000T0000Z-120904T2330Z/
PALM BEACH FL-
726 PM EDT TUE SEP 4 2012

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL PALM BEACH COUNTY
WILL EXPIRE AT 730 PM EDT...

NATIONAL WEATHER SERVICE RADAR INDICATED THAT THE THUNDERSTORM HAS
WEAKENED. THUS THE THUNDERSTORM WARNING WILL EXPIRE AT 730 PM EDT.

LAT...LON 2650 8029 2661 8041 2680 8021 2663 8004
TIME...MOT...LOC 2327Z 231DEG 18KT 2663 8021

$$

AK

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 4, 1:49 PM EDTSpecial Weather StatementMFLBroward26 min
Sep 4, 4:09 PM EDTSpecial Weather StatementMFLHendry36 min
Sep 4, 4:54 PM EDTSpecial Weather StatementMFLBroward36 min
Sep 4, 4:56 PM EDTSpecial Weather StatementMFLHendry34 min
Sep 4, 5:11 PM EDTSpecial Weather StatementMFLBroward34 min
Sep 4, 5:56 PM EDTSpecial Marine WarningMFL64 min
Sep 4, 6:02 PM EDTSpecial Weather StatementMFLPalm Beach28 min
Sep 4, 6:05 PM EDTSpecial Weather StatementMFLBroward25 min
Sep 4, 6:23 PM EDTSevere Thunderstorm WarningMFLBroward, Palm Beach21 min
Sep 4, 6:56 PM EDTSpecial Weather StatementMFLPalm Beach34 min
Sep 4, 7:38 PM EDTSpecial Weather StatementMFLPalm Beach37 min
Sep 4, 7:51 PM EDTSpecial Marine WarningMFL54 min

Nearby

Severe Thunderstorm Warnings in Florida, 2012Every severe thunderstorm warning in 2012

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.