Alert archive / Florida / Freeze Warnings in 2012

Freeze Warning 4, NWS Miami, FL

December 21, 2012Glades County, Hendry County, Florida

NWS Miami, FL issued this freeze warning at Dec 21, 2012, 2:31 PM EST for Glades County, Hendry County, Florida. It took effect at Dec 22, 2012, 2:00 AM EST. It was in force for 5 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Dec 21, 2012, 2:31 PM EST (19:31 UTC)
In effect from
Dec 22, 2012, 2:00 AM EST
Expired
Dec 22, 2012, 7:29 AM EST
In force
5 hr
Issued by
NWS Miami, FL

Counties Glades County, FL, Hendry County, FL

The radar

The Miami radar (KAMX), 148 km from the middle of the area, began a volume at 19:32 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, 7.5 hours before the alert went out and 137 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 2012-12-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 33 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 2012-12-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 148 square meters per square second.193958Sfc1 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
33 J/kg
Mixed-layer CIN
-39 J/kg
Mixed-layer LCL
957 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
148 m²/s²
0-3 km storm-relative helicity
146 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.6

Open this sounding in Storm Lab

The text

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

511 
WWUS72 KMFL 211931
NPWMFL

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE MIAMI FL
231 PM EST FRI DEC 21 2012

FLZ063-066-221400-
/O.UPG.KMFL.FZ.A.0004.121222T0700Z-121222T1400Z/
/O.NEW.KMFL.FZ.W.0004.121222T0700Z-121222T1400Z/
/O.NEW.KMFL.FZ.A.0005.121223T0700Z-121223T1400Z/
GLADES-HENDRY-
INCLUDING THE CITIES OF...MOORE HAVEN...CLEWISTON
231 PM EST FRI DEC 21 2012

...FREEZE WARNING IN EFFECT FROM 2 AM TO 9 AM EST SATURDAY...
...FREEZE WATCH IN EFFECT FROM LATE SATURDAY NIGHT THROUGH SUNDAY
MORNING...

THE NATIONAL WEATHER SERVICE IN MIAMI HAS ISSUED A FREEZE
WARNING...WHICH IS IN EFFECT FROM 2 AM TO 9 AM EST SATURDAY. A
FREEZE WATCH HAS ALSO BEEN ISSUED. THIS FREEZE WATCH IS IN EFFECT
FROM LATE SATURDAY NIGHT THROUGH SUNDAY MORNING. 

* TEMPERATURE...NEAR 32 DEGREES IN SOME SPOTS.

* IMPACTS...POTENTIAL DAMAGE TO CROPS AND OTHER SENSITIVE 
  VEGETATION. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FREEZE WARNING MEANS TEMPERATURES OF 32 DEGREES OR LOWER ARE
IMMINENT OR HIGHLY LIKELY...FOR ANY DURATION OF TIME. THESE
CONDITIONS WILL KILL CROPS AND OTHER SENSITIVE VEGETATION.

A FREEZE WATCH MEANS TEMPERATURES OF 32 DEGREES OR LOWER ARE
POSSIBLE...FOR ANY DURATION OF TIME. THESE CONDITIONS COULD KILL
CROPS AND OTHER SENSITIVE VEGETATION.

&&

$$
1 follow-up statement
587 
WWUS72 KMFL 221229
NPWMFL

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE MIAMI FL
729 AM EST SAT DEC 22 2012

FLZ063-066-222030-
/O.CAN.KMFL.FZ.W.0004.000000T0000Z-121222T1400Z/
/O.CON.KMFL.FZ.A.0005.121223T0700Z-121223T1400Z/
GLADES-HENDRY-
INCLUDING THE CITIES OF...MOORE HAVEN...CLEWISTON
729 AM EST SAT DEC 22 2012

...FREEZE WATCH REMAINS IN EFFECT FROM LATE TONIGHT THROUGH
SUNDAY MORNING...
...FREEZE WARNING IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN MIAMI HAS CANCELLED THE FREEZE
WARNING. 

* TEMPERATURE...THE TEMPERATURES ACROSS THE AFFECTED AREA HAVE
  FALLEN INTO THE MID TO UPPER 30S WITH FREEZING CONDITIONS NO
  LONGER A THREAT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FREEZE WATCH MEANS TEMPERATURES OF 32 DEGREES OR LOWER ARE
POSSIBLE...FOR ANY DURATION OF TIME. THESE CONDITIONS COULD KILL
CROPS AND OTHER SENSITIVE VEGETATION.

&&

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 21, 4:30 AM ESTWind Chill AdvisoryMFLBroward, Collier, Glades, Hendry, Miami-Dade, Palm Beach28 hr
Dec 21, 5:26 AM ESTRip Current StatementMFLCollier14 hr
Dec 21, 5:52 AM ESTRed Flag WarningMFLBroward, Miami-Dade, Palm Beach11 hr
Dec 21, 2:31 PM ESTFreeze WatchMFLGlades, Hendry23 hr

Nearby

Freeze Warnings in Florida, 2012Every freeze 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.