Alert archive / Mississippi / Mesoscale Discussions in 2008

Mesoscale Discussion 252

February 17, 20085 counties in Alabama; 40 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Feb 17, 2008, 4:19 AM CST for 5 counties in Alabama; 40 counties in Mississippi. It was in force for 56 min.

The area

The outline as issued.

The facts

Issued
Feb 17, 2008, 4:19 AM CST (10:19 UTC)
Expired
Feb 17, 2008, 5:15 AM CST
In force
56 min
Issued by
the Storm Prediction Center
All 45 counties

Colbert County, AL, Franklin County, AL, Lamar County, AL, Marion County, AL, Pickens County, AL, Alcorn County, MS, Attala County, MS, Benton County, MS, Calhoun County, MS, Carroll County, MS, Chickasaw County, MS, Choctaw County, MS, Clay County, MS, Coahoma County, MS, Grenada County, MS, Holmes County, MS, Humphreys County, MS, Itawamba County, MS, Kemper County, MS, Lafayette County, MS, Leake County, MS, Lee County, MS, Leflore County, MS, Lowndes County, MS, Madison County, MS, Marshall County, MS, Monroe County, MS, Montgomery County, MS, Neshoba County, MS, Noxubee County, MS, Oktibbeha County, MS, Panola County, MS, Pontotoc County, MS, Prentiss County, MS, Quitman County, MS, Sunflower County, MS, Tallahatchie County, MS, Tate County, MS, Tippah County, MS, Tishomingo County, MS, Union County, MS, Webster County, MS, Winston County, MS, Yalobusha County, MS, Yazoo County, MS

The radar

The Columbus AFB radar (KGWX), 91 km from the middle of the area, began a volume at 10:20 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

Little Rock, AR (KLZK), launched 00:00Z, 10.3 hours before the alert went out and 158 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-pSkew-T log-p diagram, Little Rock, AR at 00:00Z on 2008-02-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Little Rock, AR at 00:00Z on 2008-02-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 358 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
550 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
358 m²/s²
0-3 km storm-relative helicity
624 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.

000 
ACUS11 KWNS 171019
SWOMCD
SPC MCD 171019 
ALZ000-MSZ000-ARZ000-171115-

MESOSCALE DISCUSSION 0252
NWS STORM PREDICTION CENTER NORMAN OK
0419 AM CST SUN FEB 17 2008

AREAS AFFECTED...PARTS OF CENTRAL/NERN MS

CONCERNING...SEVERE THUNDERSTORM WATCH 60...

VALID 171019Z - 171115Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 60
CONTINUES.

WW 60 WILL BE ALLOWED TO EXPIRE...AS SCHEDULED AT 11Z.

ONGOING TSTMS ALONG NRN EXTENT OF SQUALL LINE...NOW MOVING THROUGH
CENTRAL MS...HAVE CONTINUED TO SHOW SIGNS OF DECREASING INTENSITY AS
INDICATED BY RECENT TRENDS IN LIGHTNING DATA.  HEIGHTS ARE EXPECTED
TO FALL ACROSS NRN MS/NWRN AL AS UPPER LOW/TROUGH APPROACHES THE MID
MS VALLEY...RESULTING IN COOLING 850-500 MB TEMPERATURES PER 07Z RUC
SOUNDINGS VALID THROUGH THIS MORNING.  THIS COMBINED WITH MOISTENING
LOW LEVELS SHOULD WEAKEN THE CAP.  HOWEVER...AT LEAST IN THE SHORT
TERM /THROUGH ABOUT MID MORNING/...TSTM ACTIVITY IS EXPECTED TO
REMAIN ELEVATED...AND THUS LIMIT THE NRN EXTENT OF SEVERE WEATHER. 
GIVEN STRENGTH OF WIND FLOW JUST OFF THE SURFACE /45-50 KT AOB 1 KM
PER AREA WSR-88D VWP AND WIND PROFILER DATA/...A FEW STRONGER WIND
GUSTS COULD STILL REACH THE SURFACE...BUT OVERALL WIND THREAT IS
EXPECTED TO REMAIN LOW ENOUGH TO PRECLUDE ISSUANCE OF A NEW WW TO
THE NE OF WW 60.

..PETERS.. 02/17/2008

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

ATTN...WFO...BMX...HUN...MEG...JAN...

32768840 32638905 32589027 32449070 33079084 34329067
34928963 35008808 34778763 33758776

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 17, 2:13 AM CSTMesoscale DiscussionSPCMobile32 min
Feb 17, 5:05 AM CSTMesoscale DiscussionSPCBaldwin, Choctaw, Clarke, Conecuh, Dallas, Escambia and 8 more55 min
Feb 17, 5:26 AM CSTTornado WatchSPCAutauga, Baldwin, Butler, Choctaw, Clarke, Conecuh and 14 more7 hr
Feb 17, 7:13 AM CSTMesoscale DiscussionSPCAutauga, Baldwin, Butler, Chilton, Choctaw, Clarke and 16 more62 min
Feb 17, 9:43 AM CSTMesoscale DiscussionSPCAutauga, Baldwin, Butler, Chilton, Choctaw, Clarke and 17 more62 min
Feb 17, 12:14 PM CSTMesoscale DiscussionSPCAutauga, Barbour, Bullock, Chambers, Clay, Coffee and 16 more91 min
Feb 17, 12:32 PM CSTTornado WatchSPCAutauga, Baldwin, Barbour, Bullock, Butler, Chambers and 28 more7 hr
Feb 17, 2:45 PM CSTMesoscale DiscussionSPCAutauga, Baldwin, Barbour, Bullock, Butler, Chambers and 22 more90 min
Feb 17, 5:19 PM CSTMesoscale DiscussionSPCChambers, Dale, Geneva, Henry, Houston86 min
Feb 16, 10:41 PM CSTMesoscale DiscussionSPCAdams, Issaquena, Washington94 min
Feb 16, 11:30 PM CSTSevere Thunderstorm WatchSPCAdams, Amite, Attala, Bolivar, Carroll, Claiborne and 25 more6 hr
Feb 17, 2:45 AM CSTTornado WatchSPCAmite, Claiborne, Clarke, Copiah, Covington, Forrest and 23 more5 hr

Nearby

Mesoscale Discussions in Mississippi, 2008Mesoscale Discussions in Alabama, 2008Every mesoscale discussion in 2008

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.