Alert archive / Florida / Mesoscale Discussions in 2007

Mesoscale Discussion 101

February 1, 20074 states

The Storm Prediction Center issued this mesoscale discussion at Feb 1, 2007, 7:56 AM CST for 4 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Feb 1, 2007, 7:56 AM CST (13:56 UTC)
Expired: Feb 1, 2007, 10:00 AM CST
In force: 2 hr
Issued by: the Storm Prediction Center

Counties Baldwin County, AL, Covington County, AL, Escambia County, AL, Geneva County, AL, Houston County, AL, Mobile County, AL, Bay County, FL, Calhoun County, FL, Escambia County, FL, Gulf County, FL, Holmes County, FL, Jackson County, FL, Okaloosa County, FL, Santa Rosa County, FL, Walton County, FL, Washington County, FL, Plaquemines Parish, LA, Saint Bernard Parish, LA, Jackson County, MS

The radar

The Mobile radar (KMOB), 91 km from the middle of the area, began a volume at 14:01 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

Slidell Radar S, LA (KSIL), launched 12:00Z, 1.9 hours before the alert went out and 188 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: 111 J/kg
Mixed-layer CIN: -57 J/kg
Mixed-layer LCL: 514 m above ground
0-6 km bulk shear: 65 kt
0-1 km storm-relative helicity: 168 m²/s²
0-3 km storm-relative helicity: 180 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

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

000 
ACUS11 KWNS 011356
SWOMCD
SPC MCD 011356 
GAZ000-FLZ000-ALZ000-MSZ000-LAZ000-011600-

MESOSCALE DISCUSSION 0101
NWS STORM PREDICTION CENTER NORMAN OK
0756 AM CST THU FEB 01 2007

AREAS AFFECTED...EXTREME SE LA / EXTREME SRN MS AND AL / WRN FL
PNHDL

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 011356Z - 011600Z

SFC-BASED TSTMS HAVE BEEN SLOWLY INCREASING OVER THE N CNTRL GULF OF
MEXICO AND EXTREME SE LA/FAR SRN MS/AL FOR THE PAST 2-3 HRS.  THIS
ACTIVITY SHOULD CONTINUE TO SLOWLY INCREASE THIS MORNING AS LOW
LEVEL MOISTURE RETURN AND LARGE SCALE ASCENT GRADUALLY INCREASE
DOWNSTREAM FROM APPARENT SHORTWAVE IMPULSE OVER E TX.  LOW TO MID
LEVEL LAPSE RATES WILL REMAIN WEAK...BUT INCREASING MOISTURE INFLOW
WITH RESULT IN FURTHER DESTABILIZATION WITH SBCAPE POSSIBLY REACHING
500 J/KG ALONG THE IMMEDIATE CNTRL GULF CST BY MID MORNING.  COUPLED
WITH MDT TO STRONG /50+ KT/ DEEP WSWLY SHEAR AND ABSENCE OF STRONG
LINEAR FORCING...POTENTIAL WILL EXIST FOR A FEW SUSTAINED SEMI-
DISCRETE STORMS/POSSIBLE SUPERCELLS WITH AN ATTENDANT THREAT FOR
BOWING SEGMENTS/HIGH WIND.

..CORFIDI.. 02/01/2007

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

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

28978978 30018967 31178732 31408502 29778521 29528762

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 31, 11:43 PM CST	Mesoscale Discussion	SPC	DeKalb, Jackson, Limestone, Madison, Marshall, Morgan	6 hr
Feb 1, 12:18 PM CST	Mesoscale Discussion	SPC	Houston	57 min
Feb 1, 12:52 PM CST	Tornado Watch	SPC	Coffee, Dale, Geneva, Henry, Houston	8 hr
Feb 1, 2:44 PM CST	Mesoscale Discussion	SPC	Alachua, Baker, Bay, Bradford, Calhoun, Columbia and 19 more	91 min
Feb 1, 3:17 PM CST	Tornado Watch	SPC	Alachua, Baker, Bradford, Clay, Columbia, Duval and 10 more	9 hr
Feb 1, 5:52 PM CST	Mesoscale Discussion	SPC	Alachua, Baker, Bay, Bradford, Calhoun, Citrus and 27 more	83 min

Nearby

Mesoscale Discussions in Florida, 2007 Mesoscale Discussions in Alabama, 2007 Mesoscale Discussions in Louisiana, 2007 Every mesoscale discussion in 2007

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.