Mesoscale Discussion 25

Issued

Jan 17, 2011, 10:17 AM EST (15:17 UTC)

Expired

Jan 17, 2011, 12:15 PM EST

In force

118 min

Issued by

the Storm Prediction Center

The Miami radar (KAMX), 150 km from the middle of the area, began a volume at 15:17 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.

• Tornado Watch 5Jan 17, 11:25 AM EST
• Tornado Watch 6Jan 17, 11:55 AM EST

478 
ACUS11 KWNS 171518
SWOMCD
SPC MCD 171517
FLZ000-171715-

MESOSCALE DISCUSSION 0025
NWS STORM PREDICTION CENTER NORMAN OK
0917 AM CST MON JAN 17 2011

AREAS AFFECTED...S FL

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 171517Z - 171715Z

PORTIONS OF CNTRL AND SRN FL WILL ARE BEING MONITORED FOR INCREASING
CONVECTIVE TRENDS AND A WW COULD BE REQUIRED LATER TODAY.

SURFACE ANALYSIS SHOWS LOW PRESSURE OVER THE ERN GULF OF MEXICO THIS
MORNING...AND ALONG AN E-W ORIENTED SURFACE BOUNDARY EXTENDING EWD
ACROSS N CNTRL FL. BUOY OBSERVATIONS INDICATE DEWPOINTS IN THE LOW
TO MID 60S F LURKING JUST OFFSHORE AHEAD OF THIS BOUNDARY...ALTHOUGH
COOL/STABLE CONDITIONS CURRENTLY EXIST OVER MUCH OF CNTRL FL WITH
DEWPOINTS ONLY IN THE 50S F.

TO THE S...A WARM FRONT WAS NOTED ACROSS THE FL KEYS AND ACROSS THE
SE COAST OF FL...WHERE SURFACE TEMPERATURES WERE ALREADY IN THE
LOWER 70S AND DEWPOINTS INTO THE MID 60S F. ADDITIONAL DEVELOPMENT
WAS OCCURRING SWD ALONG A CONFLUENCE LINE WHICH MAY DEMARCATE A
SLIGHTLY MORE UNSTABLE AIR MASS.

THERE APPEARS TO BE TWO SEPARATE THREAT AREAS OVER FL TODAY...THE
FIRST OVER THE SERN PENINSULA WHERE STORMS WILL PERSIST ALONG A
RETREATING WARM FRONT. STORMS ACROSS THE KEYS AND OFFSHORE HAVE
SHOWN SIGNS OF ROTATION AT TIMES...AND THIS TREND MAY CONTINUE AS
THE STORMS MOVE ACROSS SRN FL THIS AFTERNOON WHEN AT LEAST SOME
FURTHER DESTABILIZATION IS ANTICIPATED. WITH A MOIST AIR MASS IN
PLACE AND AMPLE SHEAR THROUGHOUT THE PROFILE...ISOLATED/BRIEF
TORNADOES MAY OCCUR.

THE SECOND AREA WILL BE ALONG THE MAIN SURFACE BOUNDARY OVER CNTRL
FL...WHERE DESTABILIZATION THROUGH ADVECTION AS WELL AS POCKETS OF
HEATING WILL OCCUR. STORMS CURRENTLY TRAINING ALONG THIS BOUNDARY
MAY STRENGTHEN THROUGH THE DAY AND BECOME MORE SURFACE BASED WITH
TIME...WITH THE MAIN THREAT BEING A FEW DAMAGING WIND GUSTS.

..JEWELL.. 01/17/2011

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

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

LAT...LON   28528126 28858073 28498044 28178055 26927997 25728002
            25358018 24938048 24838065 25028117 25338129 25628138
            25828175 26348195 26428229 26808233 27308268 27598284
            28238166 28528126

Mesoscale Discussions in Florida, 2011Every mesoscale discussion in 2011

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.