Mesoscale Discussion 24

Issued

Jan 16, 2016, 11:03 PM EST (04:03 UTC)

Expired

Jan 17, 2016, 1:00 AM EST

In force

117 min

Issued by

the Storm Prediction Center

Chance of a watch

80%

Counties Charlotte County, FL, Collier County, FL, DeSoto County, FL, Glades County, FL, Hardee County, FL, Hendry County, FL, Highlands County, FL, Lee County, FL, Manatee County, FL, Monroe County, FL, Okeechobee County, FL, Polk County, FL, Sarasota County, FL

The Tampa radar (KTBW), 123 km from the middle of the area, began a volume at 04:04 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 4Jan 17, 12:45 AM EST

692 
ACUS11 KWNS 170404
SWOMCD
SPC MCD 170403 
FLZ000-170600-

MESOSCALE DISCUSSION 0024
NWS STORM PREDICTION CENTER NORMAN OK
1003 PM CST SAT JAN 16 2016

AREAS AFFECTED...CENTRAL/SOUTHERN FLORIDA PENINSULA

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

VALID 170403Z - 170600Z

PROBABILITY OF WATCH ISSUANCE...80 PERCENT

SUMMARY...ORGANIZED SEVERE WEATHER POTENTIAL...INCLUDING THE RISK
FOR SUPERCELLS CAPABLE OF PRODUCING A STRONG TORNADO OR
TWO...APPEARS LIKELY TO INCREASE ACROSS THE FLORIDA SUN COAST DURING
THE 07-09Z TIME FRAME.  A WATCH FOR AT LEAST THIS AREA PROBABLY WILL
BE ISSUED BY 06Z.  MUCH OF THE REMAINDER OF THE CENTRAL/SOUTHERN
FLORIDA PENINSULA MAY ALSO BE INCLUDED AT THAT TIME...WITH AN
EVOLVING LINE OF STORMS EXPECTED TO RAPIDLY SPREAD INLAND AND ACROSS
THE REGION THROUGH DAYBREAK...ACCOMPANIED BY THE RISK FOR SEVERE
WIND GUSTS AND TORNADOES

DISCUSSION...LOWER/MID-TROPOSPHERIC WARM ADVECTION APPEARS TO BE
SUPPORTING ONGOING CONVECTIVE DEVELOPMENT ACROSS THE OFFSHORE SHELF
WATERS INTO FLORIDA GULF COASTAL AREAS BETWEEN FORT MYERS AND TAMPA.
IN THE PRESENCE OF WEAK MID-LEVEL LAPSE RATES...AND ROOTED ABOVE A
RESIDUAL COOL/STABLE BOUNDARY LAYER...ACTIVITY IS NOT PARTICULARLY
VIGOROUS AT THE PRESENT TIME.  AND...SOUTHERLY LOW-LEVEL WIND FIELDS
REMAIN WEAK AS WELL.

HOWEVER...BASED ON LATEST MODEL OUTPUT...INCLUDING THE RAPID REFRESH
AND HIGH RESOLUTION RAPID REFRESH...CONSIDERABLE STRENGTHENING OF
SOUTHERLY LOW-LEVEL FLOW APPEARS LIKELY WITHIN THE NEXT FEW HOURS. 
WITH THE APPROACH OF A VIGOROUS UPSTREAM SHORT WAVE TROUGH AND
ASSOCIATED SURFACE CYCLONE...NOW OVER THE CENTRAL GULF OF
MEXICO...850 MB WINDS ARE FORECAST TO INCREASE TO 50-70 KT ACROSS
COASTAL AREAS DURING THE 06-09Z TIME FRAME.  IN ADDITION TO
CONTRIBUTING TO SUBSTANTIAL STRENGTHENING OF LOW-LEVEL SHEAR...THIS
LIKELY WILL BE ACCOMPANIED BY THE NORTHWARD ADVECTION OF MORE
SUBSTANTIVE BOUNDARY LAYER MOISTURE NOW PRESENT ACROSS THE FLORIDA
STRAITS AND SOUTHEASTERN GULF OF MEXICO.  

ASSOCIATED DESTABILIZATION LIKELY WILL BECOME MORE CONDUCIVE TO
ORGANIZED SEVERE STORM DEVELOPMENT...WHICH MAY MATERIALIZE INITIALLY
AS DISCRETE SUPERCELLS ALONG A CONFLUENCE AXIS ASSOCIATED WITH THE
850 MB JET.  THIS COULD IMPACT COASTAL AREAS AROUND FORT
MYERS...NORTHWARD TOWARD SARASOTA...PERHAPS TAMPA BAY ...AS EARLY AS
08-09Z WITH A RISK FOR TORNADOES...ONE OR TWO OF WHICH COULD BE
STRONG.

..KERR/HART.. 01/17/2016

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

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

LAT...LON   27648272 28228184 27958102 27128042 26168049 25288090
            24598237 26188216 26988259 27648272

Mesoscale Discussions in Florida, 2016Every mesoscale discussion in 2016

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.