Alert archive / Mississippi / Mesoscale Discussions in 2016

Mesoscale Discussion 37

January 21, 20168 counties in Alabama; Escambia County, Okaloosa County, Santa Rosa County, Florida; 9 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Jan 21, 2016, 5:29 PM CST for 8 counties in Alabama; Escambia County, Okaloosa County, Santa Rosa County, Florida; 9 counties in Mississippi. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Jan 21, 2016, 5:29 PM CST (23:29 UTC)
Expired: Jan 21, 2016, 7:30 PM CST
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 80%

Counties Baldwin County, AL, Choctaw County, AL, Clarke County, AL, Conecuh County, AL, Escambia County, AL, Mobile County, AL, Monroe County, AL, Washington County, AL, Escambia County, FL, Okaloosa County, FL, Santa Rosa County, FL, Clarke County, MS, George County, MS, Greene County, MS, Harrison County, MS, Jackson County, MS, Lauderdale County, MS, Perry County, MS, Stone County, MS, Wayne County, MS

The radar

The Mobile radar (KMOB), 49 km from the middle of the area, began a volume at 23:29 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Tornado Watch 7Jan 21, 6:30 PM CST

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 11.5 hours before the alert went out and 187 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: 208 J/kg
Mixed-layer CIN: -93 J/kg
Mixed-layer LCL: 600 m above ground
0-6 km bulk shear: 55 kt
0-1 km storm-relative helicity: 146 m²/s²
0-3 km storm-relative helicity: 184 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.2

Open this sounding in Storm Lab

The text

As transmitted.

556 
ACUS11 KWNS 212329
SWOMCD
SPC MCD 212329 
FLZ000-ALZ000-MSZ000-220130-

MESOSCALE DISCUSSION 0037
NWS STORM PREDICTION CENTER NORMAN OK
0529 PM CST THU JAN 21 2016

AREAS AFFECTED...SERN MS / SWRN AL / WRN FL PANHANDLE

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

VALID 212329Z - 220130Z

PROBABILITY OF WATCH ISSUANCE...80 PERCENT

SUMMARY...A TORNADO WATCH WILL LIKELY BE ISSUED PRIOR TO 02Z.

DISCUSSION...SURFACE OBSERVATIONS OVER SERN LA AND BUOYS E OF THE
MOUTH OF THE MS RIVER INDICATE THE MARITIME FRONT IS ROUGHLY 50 MI S
OF THE BARRIER ISLANDS OF MS AND AL.  AS THE BOUNDARY ADVANCES NWD
THIS EVENING COINCIDENT WITH THE APPROACH OF THE MID- TO UPPER-LEVEL
TROUGH...A MORE FAVORABLE JUXTAPOSITION OF THE VEERING AND
STRENGTHENING WIND PROFILE WITH HEIGHT AND A MARGINALLY BUOYANT
AIRMASS WILL SUPPORT 1) ISOLD STRONG TO SEVERE STORMS TO MOVE INTO
THE REGION FROM THE W...AND 2) WARM SECTOR STORM DEVELOPMENT FROM
THE CONTINENTAL SHELF VICINITY MOVING ASHORE AND POSING A SEVERE
RISK.  PRIOR TO THE CONVECTIVE LINE PASSAGE OVER THE MOBILE BAY AND
WRN FL PANHANDLE VICINITY LATER TONIGHT...MODEL FORECAST SOUNDINGS
SHOW 0-1 KM SRH INCREASING TO AOA 300 M2 PER S2---COMPARATIVELY
HIGHER THAN VALUES OVER THE LOWER MS VALLEY THIS AFTERNOON.  AS
SUCH...A TORNADO WATCH WILL LIKELY BE REQUIRED LATER THIS EVENING
ONCE STORMS ENCROACH ON THE AREA FROM THE S AND W.

..SMITH/CORFIDI.. 01/21/2016

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

ATTN...WFO...TAE...BMX...MOB...JAN...LIX...

LAT...LON   30278951 32498881 32108747 30918633 30338629 30278951

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 21, 11:03 AM CST	Mesoscale Discussion	SPC	Attala, Hinds, Leake, Madison, Warren, Yazoo	87 min
Jan 21, 1:44 PM CST	Mesoscale Discussion	SPC	Adams, Amite, Claiborne, Copiah, Covington, Forrest and 13 more	2 hr
Jan 21, 2:14 PM CST	Tornado Watch	SPC	Adams, Amite, Claiborne, Clarke, Copiah, Covington and 26 more	6 hr
Jan 21, 4:57 PM CST	Mesoscale Discussion	SPC	Amite, Jefferson Davis, Lawrence, Lincoln, Pike, Simpson and 2 more	63 min

Nearby

Mesoscale Discussions in Mississippi, 2016 Mesoscale Discussions in Alabama, 2016 Mesoscale Discussions in Florida, 2016 Every 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.