Alert archive / Florida / Mesoscale Discussions in 2011

Mesoscale Discussion 192

March 5, 20115 counties in Alabama; 8 counties in Florida

The Storm Prediction Center issued this mesoscale discussion at Mar 5, 2011, 7:12 PM CST for 5 counties in Alabama; 8 counties in Florida. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued: Mar 5, 2011, 7:12 PM CST (01:12 UTC)
Expired: Mar 5, 2011, 8:45 PM CST
In force: 93 min
Issued by: the Storm Prediction Center

Counties Coffee County, AL, Covington County, AL, Dale County, AL, Geneva County, AL, Houston County, AL, Bay County, FL, Calhoun County, FL, Gulf County, FL, Holmes County, FL, Jackson County, FL, Okaloosa County, FL, Walton County, FL, Washington County, FL

The radar

The Eglin Afb radar (KEVX), 30 km from the middle of the area, began a volume at 01:12 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 00:00Z, 1.2 hours before the alert went out and 166 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: 3 J/kg
Mixed-layer CIN: -51 J/kg
Mixed-layer LCL: 1138 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 136 m²/s²
0-3 km storm-relative helicity: 142 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.

879 
ACUS11 KWNS 060112
SWOMCD
SPC MCD 060112 
FLZ000-ALZ000-060245-

MESOSCALE DISCUSSION 0192
NWS STORM PREDICTION CENTER NORMAN OK
0712 PM CST SAT MAR 05 2011

AREAS AFFECTED...SERN AL AND THE WRN FL PANHANDLE

CONCERNING...TORNADO WATCH 40...

VALID 060112Z - 060245Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 40 CONTINUES.

A THREAT FOR ISOLATED DAMAGING WIND AS WELL AS AN ISOLATED TORNADO
OR TWO WILL PERSIST NEXT COUPLE HOURS MAINLY NEAR COASTAL AREAS OF
THE FL PANHANDLE.

THIS EVENING A PRE-FRONTAL LINE OF STORMS EXTENDS FROM A MESO-LOW IN
SWRN AL NEAR THE FL BORDER SWD INTO THE NERN GULF MOVING EAST AT 30
KT. LATEST OBJECTIVE ANALYSIS AND SURFACE DATA INDICATE THE HIGHER
THETA-E BOUNDARY LAYER AIR AND GREATER INSTABILITY REMAIN OFFSHORE
WITH MLCAPE BELOW 500 J/KG INLAND FROM COAST. LIGHTNING TRENDS
CONFIRM A WEAK THERMODYNAMIC ENVIRONMENT INLAND WITH MOST STRIKES
CONFINED TO PORTION OF LINE ALONG AND SOUTH OF THE COAST. ACTIVITY
IS EMBEDDED WITHIN STRONG VERTICAL SHEAR WITH LARGE 0-1 KM
HODOGRAPHS. LEWP STRUCTURES CONTINUE TO BE OBSERVED OFF THE COAST OF
FL...AND THIS ACTIVITY WILL REMAIN CAPABLE OF ISOLATED WIND DAMAGE
AND A TORNADO OR TWO ESPECIALLY AS IT APPROACHES THE MIDDLE FL
PANHANDLE WHERE THE TERRAIN BENDS FARTHER SWD.

THE 00Z TALLAHASSEE SOUNDING WAS SAMPLED EAST OF PRIMARY MOIST AXIS
AND SHOWS VERY LITTLE INSTABILITY. MODEST DESTABILIZATION MAY OCCUR
FARTHER EAST DUE TO LOW-LEVEL THETA-E ADVECTION. HOWEVER...TENDENCY
WILL PROBABLY BE FOR LINE TO WEAKEN AS IT ADVANCES EWD LATER THIS
EVENING. WATCH DECISION DOWNSTREAM FROM CURRENT WW WILL ULTIMATELY
DEPEND ON CONVECTIVE TRENDS.

..DIAL.. 03/06/2011

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

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

LAT...LON   31618600 31488530 30588497 29798529 29668595 30438649
            30968686 31418681 31618600

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Mar 5, 9:19 PM CST	Mesoscale Discussion	SPC	Gadsden, Liberty	56 min
Mar 6, 12:29 PM CST	Mesoscale Discussion	SPC	Indian River, Martin, Okeechobee, Palm Beach, Saint Lucie	2 hr

Nearby

Mesoscale Discussions in Florida, 2011 Mesoscale Discussions in Alabama, 2011 Every 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.