Alert archive / Florida / Mesoscale Discussions in 2011

Mesoscale Discussion 45

January 25, 201113 counties in Florida

The Storm Prediction Center issued this mesoscale discussion at Jan 25, 2011, 7:20 PM EST for 13 counties in Florida. It was in force for 55 min.

The area

The outline as issued.

The facts

Issued
Jan 25, 2011, 7:20 PM EST (00:20 UTC)
Expired
Jan 25, 2011, 8:15 PM EST
In force
55 min
Issued by
the Storm Prediction Center

Counties Brevard County, FL, Charlotte County, FL, Collier County, FL, DeSoto County, FL, Glades County, FL, Hendry County, FL, Highlands County, FL, Indian River County, FL, Lee County, FL, Martin County, FL, Okeechobee County, FL, Palm Beach County, FL, Saint Lucie County, FL

The radar

The Tampa radar (KTBW), 131 km from the middle of the area, began a volume at 00:23 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Miami, FL (KMFL), launched 00:00Z, 0.3 hours before the alert went out and 168 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 2011-01-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1046 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 2011-01-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 201 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
1046 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
569 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
201 m²/s²
0-3 km storm-relative helicity
276 m²/s²
Significant tornado parameter
1.3
Supercell composite
8.2

Open this sounding in Storm Lab

The text

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

751 
ACUS11 KWNS 260020
SWOMCD
SPC MCD 260020 
FLZ000-260115-

MESOSCALE DISCUSSION 0045
NWS STORM PREDICTION CENTER NORMAN OK
0620 PM CST TUE JAN 25 2011

AREAS AFFECTED...CNTRL/SRN FL

CONCERNING...TORNADO WATCH 7...

VALID 260020Z - 260115Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 7 CONTINUES.

QLCS/DISCRETE SUPERCELLS CONTINUE TO PROPAGATE ESE ACROSS CNTRL/SW
FL...WELL-AHEAD OF MESOSCALE MODEL TIMING.  PRIMARY UNCERTAINTY FOR
THE NEXT FEW HOURS WILL BE HOW FAR S THE SEVERE THREAT WILL EVOLVE. 


HIGHEST POTENTIAL FOR TORNADOES AND DAMAGING WIND GUSTS WILL EXIST
FROM AREAS NW-N OF LAKE OKEECHOBEE INTO THE VERO BEACH-MELBOURNE
REGION THROUGH 01Z.  HERE...CORE OF SSWLY LLJ OF 40-50 KTS
EXISTS...YIELDING STRONGLY VEERING 0-1KM PROFILES WITH SRH OF
350-400 M2/S2 BASED OFF THE MLB VWP.  

STRONGEST PORTION OF THE LLJ WILL BEGIN SHIFTING NE AWAY FROM FL BY
LATE EVENING AS THE SRN STREAM WAVE ACCELERATES ENE. AIR MASS ACROSS
S FL WILL REMAIN UNSTABLE...AND WITH AT LEAST WEAK HEIGHT FALLS
SPREADING ACROSS THE REGION...THUNDERSTORMS WILL REMAIN POSSIBLE S
OF THE CURRENT WATCH THIS EVENING.  WIND PROFILES BECOME
INCREASINGLY VEERED WITH TIME WITH AT LEAST 35-40 KTS OF H85-H7
FLOW.  THIS SUGGESTS THAT STORMS MAY AT LEAST POSE AN ISOLATED
DAMAGING WIND THREAT ACROSS S FL.

..RACY.. 01/26/2011

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...MFL...MLB...TBW...

LAT...LON   26388254 27728147 28358081 28658059 28408018 27318009
            26298054 25838133 25798198 26138246 26388254

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 25, 8:03 PM ESTTornado WatchSPCBroward, Collier, Glades, Hendry, Indian River, Martin and 3 more4 hr
Jan 25, 9:51 PM ESTMesoscale DiscussionSPCBroward, Miami-Dade, Palm Beach54 min

Nearby

Mesoscale Discussions in Florida, 2011Every mesoscale discussion 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.