Alert archive / Mississippi / Mesoscale Discussions in 2011

Mesoscale Discussion 13

January 9, 201110 counties in Alabama; 27 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Jan 9, 2011, 3:06 PM CST for 10 counties in Alabama; 27 counties in Mississippi. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued: Jan 9, 2011, 3:06 PM CST (21:06 UTC)
Expired: Jan 9, 2011, 7:00 PM CST
In force: 4 hr
Issued by: the Storm Prediction Center

All 37 counties

Bibb County, AL, Choctaw County, AL, Dallas County, AL, Greene County, AL, Hale County, AL, Marengo County, AL, Perry County, AL, Pickens County, AL, Sumter County, AL, Tuscaloosa County, AL, Attala County, MS, Carroll County, MS, Choctaw County, MS, Clarke County, MS, Copiah County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Jasper County, MS, Kemper County, MS, Lauderdale County, MS, Leake County, MS, Lowndes County, MS, Madison County, MS, Montgomery County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Oktibbeha County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Simpson County, MS, Smith County, MS, Warren County, MS, Winston County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 126 km from the middle of the area, began a volume at 21:06 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

Jackson, MS (KJAN), launched 12:00Z, 9.1 hours before the alert went out and 133 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1327 m above ground
0-6 km bulk shear: 64 kt
0-1 km storm-relative helicity: 75 m²/s²
0-3 km storm-relative helicity: 139 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.

773 
ACUS11 KWNS 092107
SWOMCD
SPC MCD 092106
ALZ000-MSZ000-LAZ000-100100-

MESOSCALE DISCUSSION 0013
NWS STORM PREDICTION CENTER NORMAN OK
0306 PM CST SUN JAN 09 2011

AREAS AFFECTED...CNTRL AND N-CNTRL MS / W-CNTRL AL

CONCERNING...WINTER MIXED PRECIPITATION

VALID 092106Z - 100100Z

INTENSIFYING MIXED PRECIP RATES ARE FORECAST TO DEVELOP OVER THE
NEXT FEW HOURS ACROSS MS AND THEN SHIFT EWD INTO W-CNTRL AL BY EARLY
EVENING.  HOURLY LIQUID EQUIVALENT PRECIP RATES RANGING FROM
0.05-0.10 INCH ARE EXPECTED FOR SEVERAL HOURS WITH LOCALLY HIGHER
RATES POSSIBLE.

EARLY AFTERNOON SATELLITE IMAGERY INDICATES THAT A ZONE OF STRONG
DEEP LAYER ASCENT /DCVA/ IS MOVING ENEWD ACROSS THE SABINE RIVER
VALLEY THIS AFTERNOON AND WILL MOVE ACROSS THE LOWER MS VALLEY THIS
EVENING.  AHEAD OF THIS FEATURE...WARM CONVEYER UPGLIDE IS OCCURRING
ABOVE A SHALLOW COLD DOME THAT IS CONTINUING TO DRAW COOL/DRY AIR
INTO THE REGION FROM A SLOW TO ERODE SURFACE HIGH OVER THE OH
VALLEY.  THUS...INITIAL MOISTENING IS OCCURRING IN THE MID-LEVELS AS
SEEN BY JAN/BMX 12-18Z RAOBS.  RICHER MOISTURE CONTENT ALONG THE
GULF COAST VICINITY HAS BEGUN TO GRADUALLY MOVE NWD INTO THE LOWER
MS VALLEY PER REGIONAL RADAR MOSAIC DATA THE PAST FEW HOURS.  AS
THIS OCCURS...EXPECT THE PRE-CONDITIONED COLUMN TO SATURATE QUICKLY
AND RESULT IN WET-BULB COOLING AND ONSET OF APPRECIABLE PRECIP RATES
/0.05-0.10 INCH PER HOUR/.  FORECAST SOUNDINGS INDICATE FREEZING
RAIN WILL PRIMARILY BE THE PRECIP TYPE INVOF THE I-20 CORRIDOR WITH
SLEET/SNOW FARTHER N AND NW NEAR HWY 82.

..SMITH.. 01/09/2011

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

ATTN...WFO...BMX...MOB...MEG...JAN...

LAT...LON   32248706 31858756 31799063 32139090 32969101 33359061
            33738825 33638737 32978686 32248706

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 9, 7:09 AM CST	Mesoscale Discussion	SPC	Hinds, Issaquena, Sharkey, Warren, Yazoo	5 hr

Nearby

Mesoscale Discussions in Mississippi, 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.