Alert archive / Florida / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 13, NWS Miami, FL

April 5, 2011Broward County, Palm Beach County, Florida

NWS Miami, FL issued this severe thunderstorm warning at Apr 5, 2011, 1:40 PM EDT for Broward County, Palm Beach County, Florida. It was in force for 35 min. 7 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Apr 5, 2011, 1:40 PM EDT (17:40 UTC)
Expired: Apr 5, 2011, 2:15 PM EDT
In force: 35 min
Issued by: NWS Miami, FL
Area: Storm-based polygon

Counties Broward County, FL, Palm Beach County, FL

The radar

The Miami radar (KAMX), 110 km from the middle of the area, began a volume at 17:42 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.

What was reported inside it

Time	Report	Where	Remark
Apr 5, 1:40 PM EDT	TSTM WND GST 45	Boca Raton, FL	A THUNDERSTORM WIND GUST OF 39 KTS...OR 45 MPH...WAS RECORDED BY A MESONET SENSOR IN BOCA RATON AT 140 PM EDT.
Apr 5, 1:40 PM EDT	TSTM WND GST 48	Delray Beach, FL	A THUNDERSTORM WIND GUST OF 42 KTS...OR 48 MPH...WAS RECORDED BY A MESONET SENSOR IN DELRAY BEACH AT 140 PM EDT.
Apr 5, 1:50 PM EDT	TSTM WND GST 53	Deerfield Beach, FL	A THUNDERSTORM WIND GUST OF 46 KTS...OR 53 MPH...WAS RECORDED BY A MESONET SENSOR IN DEERFIELD BEACH AT 150 PM EDT.
Apr 5, 1:55 PM EDT	TSTM WND GST 54	Tamarac, FL	A THUNDERSTORM WIND GUST OF 47 KTS...OR 54 MPH...WAS RECORDED BY A MESONET SENSOR IN TAMARAC AT 155 PM EDT.
Apr 5, 1:58 PM EDT	TSTM WND GST 51	Pompano Beach, FL	A THUNDERSTORM WIND GUST OF 44 KTS...OR 51 MPH...WAS RECORDED BY THE ASOS AT THE POMPANO BEACH AIRPORT AT 158 PM EDT.
Apr 5, 2:00 PM EDT	FUNNEL CLOUD	Boynton Beach, FL	A TRAINED SPOTTER REPORTED A FUNNEL CLOUD JUST OFF THE BEACH MOVING AWAY FROM THE COAST...BUT BECAME OBSCURED BY HEAVY RAIN. WINDS ESTIMATED AROUND 60 MPH WITH A PASSING GUST FRONT AND THUNDERSTORMS.
Apr 5, 2:00 PM EDT	TSTM WND GST 51	Pompano Beach, FL	A THUNDERSTORM WIND GUST OF 44 KTS...OR 51 MPH...WAS RECORDED BY THE ASOS AT THE POMPANO BEACH AIRPORT AT 200 PM EDT.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Miami, FL (KMFL), launched 12:00Z, 5.7 hours before the alert went out and 84 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2028 J/kg
Mixed-layer CIN: -1 J/kg
Mixed-layer LCL: 645 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 155 m²/s²
0-3 km storm-relative helicity: 208 m²/s²
Significant tornado parameter: 1.6
Supercell composite: 9.0

Open this sounding in Storm Lab

The text

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

571 
WUUS52 KMFL 051740
SVRMFL
FLC011-099-051815-
/O.NEW.KMFL.SV.W.0013.110405T1740Z-110405T1815Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MIAMI FL
140 PM EDT TUE APR 5 2011

THE NATIONAL WEATHER SERVICE IN MIAMI HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN BROWARD COUNTY IN SOUTH FLORIDA.
  EASTERN PALM BEACH COUNTY IN SOUTH FLORIDA.

* UNTIL 215 PM EDT

* AT 138 PM EDT...NATIONAL WEATHER SERVICE METEOROLOGISTS HAVE
  DETECTED A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING PENNY
  SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS
  WERE LOCATED ALONG A LINE EXTENDING FROM 5 MILES EAST OF NORTH PALM
  BEACH TO 20 MILES WEST OF CORAL SPRINGS...AND MOVING EAST AT 35
  MPH.

* THE LINE OF STORMS WILL AFFECT...
  HAVERHILL...
  GREENACRES CITY...
  LAKE WORTH...
  BOYNTON BEACH...
  DELRAY BEACH...
  CORAL SPRINGS...
  AND SURROUNDING COMMUNITIES.

SURFACE OBSERVATIONS AT WEST PALM BEACH AIRPORT REPORTED 60 MPH WIND 
GUSTS WITH THESE STORMS.R

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS CAN PRODUCE VERY STRONG 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 2655 8003 2655 8004 2629 8007 2619 8009
      2616 8012 2631 8076 2697 8007 2682 8002
      2678 8002 2678 8005 2675 8002
TIME...MOT...LOC 1739Z 283DEG 31KT 2679 7997 2635 8057

$$

PS

2 follow-up statements

034 
WWUS52 KMFL 051806
SVSMFL

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MIAMI FL
206 PM EDT TUE APR 5 2011

FLC011-099-051815-
/O.CON.KMFL.SV.W.0013.000000T0000Z-110405T1815Z/
PALM BEACH FL-BROWARD FL-
206 PM EDT TUE APR 5 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 215 PM EDT
FOR NORTHEASTERN BROWARD AND SOUTHEASTERN PALM BEACH COUNTIES...

AT 201 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING 
DAMAGING WINDS IN EXCESS OF 60 MPH. SMALL HAIL IS ALSO POSSIBLE. 
THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM DELRAY BEACH 
TO TAMARAC...MOVING SOUTHEAST AT 45 MPH.

THE SEVERE THUNDERSTORMS WILL BE NEAR...
MARGATE...
DEERFIELD BEACH...
SEA RANCH LAKES...
AND SURROUNDING COMMUNITIES.

SEVERE THUNDERSTORMS CAN PRODUCE VERY STRONG 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 2627 8054 2659 8019 2658 8008 2659 8004
      2655 8003 2655 8004 2629 8007 2619 8009
      2616 8012
TIME...MOT...LOC 1806Z 293DEG 40KT 2642 8002 2620 8026

$$

PS

887 
WWUS52 KMFL 051814
SVSMFL

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MIAMI FL
214 PM EDT TUE APR 5 2011

FLC011-099-051822-
/O.EXP.KMFL.SV.W.0013.000000T0000Z-110405T1815Z/
PALM BEACH FL-BROWARD FL-
214 PM EDT TUE APR 5 2011

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN BROWARD AND
SOUTHEASTERN PALM BEACH COUNTIES WILL EXPIRE AT 215 PM EDT...

NATIONAL WEATHER SERVICE RADAR INDICATED THAT THE THUNDERSTORMS HAVE
MOVED OUT OF THE WARNED AREA. THUS THE THUNDERSTORM WARNING WILL 
EXPIRE AT 215 PM EDT. 

HOWEVER...THUNDERSTORMS REMAIN IN THE AREA AND A SIGNIFICANT 
WEATHER ADVISORY REMAINS IN EFFECT FOR THE BROWARD SECTOR OF THE 
WARNED AREA. LIGHTNING...GUSTY WINDS OF 45 TO 55 MPH...VERY HEAVY 
RAINFALL AND SMALL HAIL ARE STILL POSSIBLE. STAY TUNED TO NOAA 
WEATHER RADIO OR LOCAL MEDIA FOR THE LATEST UPDATES.

LAT...LON 2627 8054 2659 8019 2658 8008 2659 8004
      2655 8003 2655 8004 2629 8007 2619 8009
      2616 8012
TIME...MOT...LOC 1812Z 293DEG 40KT 2645 8000 2623 8024

$$

PS

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 5, 4:18 AM EDT	Small Craft Advisory	MFL		15 hr
Apr 5, 11:22 AM EDT	Special Weather Statement	MFL	Glades	53 min
Apr 5, 11:50 AM EDT	Special Marine Warning	MFL		85 min
Apr 5, 12:04 PM EDT	Special Weather Statement	MFL	Collier, Glades, Hendry	56 min
Apr 5, 12:42 PM EDT	Special Marine Warning	MFL		93 min
Apr 5, 12:47 PM EDT	Special Weather Statement	MFL	Collier, Hendry, Palm Beach	43 min
Apr 5, 1:06 PM EDT	Special Weather Statement	MFL	Broward	24 min
Apr 5, 1:26 PM EDT	Special Weather Statement	MFL	Broward, Palm Beach	34 min
Apr 5, 1:34 PM EDT	Special Marine Warning	MFL		56 min
Apr 5, 1:54 PM EDT	Special Weather Statement	MFL	Broward	36 min
Apr 5, 2:02 PM EDT	Special Marine Warning	MFL		58 min
Apr 5, 2:25 PM EDT	Special Marine Warning	MFL		95 min
Apr 5, 2:31 PM EDT	Special Weather Statement	MFL	Miami-Dade	59 min
Apr 5, 2:59 PM EDT	Special Marine Warning	MFL		61 min
Apr 5, 3:52 PM EDT	Special Marine Warning	MFL		83 min

Nearby

Severe Thunderstorm Warnings in Florida, 2011 Every severe thunderstorm warning in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.