Alert archive / Florida / Mesoscale Discussions in 2012

Mesoscale Discussion 735

May 6, 2012Baldwin County, Alabama; 16 counties in Florida; 5 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at May 6, 2012, 4:41 PM CDT for Baldwin County, Alabama; 16 counties in Florida; 5 counties in Georgia. It was in force for 64 min.

The area

The outline as issued.

The facts

Issued: May 6, 2012, 4:41 PM CDT (21:41 UTC)
Expired: May 6, 2012, 5:45 PM CDT
In force: 64 min
Issued by: the Storm Prediction Center

All 22 counties

Baldwin County, AL, Bay County, FL, Calhoun County, FL, Escambia County, FL, Gadsden County, FL, Gulf County, FL, Holmes County, FL, Jackson County, FL, Jefferson County, FL, Leon County, FL, Liberty County, FL, Madison County, FL, Okaloosa County, FL, Santa Rosa County, FL, Wakulla County, FL, Walton County, FL, Washington County, FL, Brooks County, GA, Decatur County, GA, Grady County, GA, Seminole County, GA, Thomas County, GA

The radar

The Eglin Afb radar (KEVX), 33 km from the middle of the area, began a volume at 21:45 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

Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 9.7 hours before the alert went out and 126 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: 900 J/kg
Mixed-layer CIN: -74 J/kg
Mixed-layer LCL: 859 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 9 m²/s²
0-3 km storm-relative helicity: 7 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

749 
ACUS11 KWNS 062142
SWOMCD
SPC MCD 062141
FLZ000-GAZ000-ALZ000-062245-

MESOSCALE DISCUSSION 0735
NWS STORM PREDICTION CENTER NORMAN OK
0441 PM CDT SUN MAY 06 2012

AREAS AFFECTED...SRN AL/GA...FL PANHANDLE

CONCERNING...SEVERE THUNDERSTORM WATCH 257...

VALID 062141Z - 062245Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 257
CONTINUES.

SUMMARY...A LOOSELY ORGANIZED COMPLEX OF STRONG TO SEVERE
THUNDERSTORMS WILL CONTINUE TO DRIFT SWD TOWARD THE GULF COAST.
COUNTIES IN THE WAKE OF THIS COMPLEX HAVE BEEN RAIN COOLED AND MAY
BE CLEARED.

DISCUSSION...A SERIES OF OUTFLOW BOUNDARIES HAVE INITIATED NEW
CONVECTION ACROSS THE WW AREA...WITH 2130Z VISIBLE IMAGERY CLEARLY
SHOWING A LARGE OUTFLOW MERGER ACROSS THE FL PANHANDLE. THE SURFACE
OBSERVATION AT TLH SHOWS THAT TEMPERATURES HAVE WARMED MUCH HIGHER
THAN MODEL FORECAST ACROSS INTERIOR AREAS...WITH SOME MIXING
MAINTAINING MID 60S DEW POINTS. GIVEN STEEP LOW LEVEL LAPSE RATES
AND EVAPORATIVE COOLING POTENTIAL...DMGG WIND POTENTIAL MAY BE
SOMEWHAT ENHANCED OVER THE NEXT FEW HOURS AS NEW INITIATION OCCURS
CLOSER TO THE COAST. HOWEVER...SURGING OUTFLOW BOUNDARIES MAY ALSO
INTERFERE WITH MORE SUSTAINED UPDRAFTS AT TIMES...RESULTING IN
WEAKENING OLDER CONVECTION INLAND AS WELL. HAIL STILL REMAINS
POSSIBLE WITH STRONGER CORES. WEAK DEEP LAYER WINDS SUGGEST
GENERALLY DISORGANIZED PULSE AND MULTICELLULAR STORMS SHOULD
CONTINUE.

..HURLBUT.. 05/06/2012

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

ATTN...WFO...JAX...TAE...MOB...

LAT...LON   30948791 30908664 30968487 30918365 30618313 30198343
            29848473 29728525 29848536 30048545 30478677 30428784
            30948791

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 6, 12:04 PM CDT	Mesoscale Discussion	SPC	Barbour, Bullock, Butler, Choctaw, Clarke, Coffee and 17 more	86 min
May 6, 12:50 PM CDT	Severe Thunderstorm Watch	SPC	Baldwin, Butler, Clarke, Coffee, Conecuh, Covington and 8 more	5 hr
May 6, 1:38 PM CDT	Mesoscale Discussion	SPC	Sumter	2 hr

Nearby

Mesoscale Discussions in Florida, 2012 Mesoscale Discussions in Georgia, 2012 Mesoscale Discussions in Alabama, 2012 Every mesoscale discussion in 2012

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.