Alert archive / Florida / Mesoscale Discussions in 2016

Mesoscale Discussion 14

January 9, 20165 counties in Florida

The Storm Prediction Center issued this mesoscale discussion at Jan 9, 2016, 2:41 PM EST for 5 counties in Florida. It was in force for 64 min.

The area

The outline as issued.

The facts

Issued
Jan 9, 2016, 2:41 PM EST (19:41 UTC)
Expired
Jan 9, 2016, 3:45 PM EST
In force
64 min
Issued by
the Storm Prediction Center
Chance of a watch
40%

Counties Charlotte County, FL, Lee County, FL, Manatee County, FL, Pinellas County, FL, Sarasota County, FL

The radar

The Tampa radar (KTBW), 56 km from the middle of the area, began a volume at 19:42 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.

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 12:00Z, 7.7 hours before the alert went out and 56 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, Tampa Bay, FL at 12:00Z on 2016-01-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 45 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, Tampa Bay, FL at 12:00Z on 2016-01-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 179 square meters per square second.1939587897117136Sfc1 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
45 J/kg
Mixed-layer CIN
-162 J/kg
Mixed-layer LCL
822 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
179 m²/s²
0-3 km storm-relative helicity
261 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

658 
ACUS11 KWNS 091942
SWOMCD
SPC MCD 091941 
FLZ000-092045-

MESOSCALE DISCUSSION 0014
NWS STORM PREDICTION CENTER NORMAN OK
0141 PM CST SAT JAN 09 2016

AREAS AFFECTED...FLORIDA PENINSULA GULF COAST

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 091941Z - 092045Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...STRONG TO SEVERE STORMS ARE SPREADING TOWARD AREAS
NEAR/SOUTH OF TAMPA BAY...AND MAY REACH COASTAL AREAS DURING THE
21-23Z TIME FRAME.  AREAL COVERAGE/EXTENT OF SEVERE WEATHER
POTENTIAL STILL SEEMS LOW ENOUGH THAT A WATCH PROBABLY IS NOT
NEEDED...BUT TRENDS WILL CONTINUE TO BE MONITORED FOR THIS
POSSIBILITY.  SEVERE WEATHER PROBABILITIES ARE BEING INCREASED TO A
CATEGORICAL SLIGHT RISK FOR PORTIONS OF THIS AREA IN THE UPCOMING
20Z CONVECTIVE OUTLOOK.

DISCUSSION...CONVECTION WITH EMBEDDED THUNDERSTORMS...ASSOCIATED
WITHIN AN AREA OF BROAD LARGE-SCALE ASCENT AND DESTABILIZATION OVER
THE NORTHEASTERN GULF OF MEXICO...IS IN THE PROCESS OF DEVELOPING
EASTWARD TOWARD THE FLORIDA PENINSULA GULF COAST.  THE LEADING EDGE
OF THIS ACTIVITY APPEARS LIKELY TO REACH COASTAL AREAS DURING THE
21-23Z TIME FRAME...BEFORE ATTEMPTING TO SPREAD INLAND.  

THIS ACTIVITY INCLUDES SEVERAL DISCRETE CELLS...SOME WITH STRONG
MID-LEVEL ROTATION EVIDENT...PERHAPS WITHIN A ZONE OF ENHANCED
LOWER/MID TROPOSPHERIC SHEAR ALONG AN EFFECTIVE WARM FRONTAL ZONE TO
THE WEST AND SOUTHWEST OF TAMPA BAY,  THE LATEST RAPID REFRESH
SUGGESTS THAT MODEST STRENGTHENING OF SOUTHWESTERLY 850 MB FLOW TO
AROUND 30 KT MAY ACCOMPANY THE INLAND PROGRESSION OF THIS CONVECTION
THOUGH EARLY EVENING.  IT REMAINS A BIT UNCLEAR WHETHER THERE WILL
BE MUCH FURTHER BOUNDARY LAYER MOISTENING/DEEPENING ACROSS THE
COASTAL WATERS INTO COASTAL AREAS.  BUT IF THIS DOES OCCUR...THE
RISK WILL INCREASE FOR SUPERCELLS SPREADING INLAND WITH POTENTIAL
FOR SEVERE HAIL AND PERHAPS A TORNADO OR TWO.

..KERR/WEISS.. 01/09/2016

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

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

LAT...LON   28348292 28148261 27788230 26968162 26468162 26048212
            26078310 26398370 27808436 28688430 28508324 28348292

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jan 9, 11:03 AM ESTMesoscale DiscussionSPCBay, Calhoun, Escambia, Gulf, Holmes, Jackson and 5 more117 min

Nearby

Mesoscale Discussions in Florida, 2016Every mesoscale discussion in 2016

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.