Alert archive / Mississippi / Mesoscale Discussions in 2003

Mesoscale Discussion 976

May 14, 200324 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at May 14, 2003, 2:28 PM CDT for 24 counties in Mississippi. It was in force for 62 min.

The area

The outline as issued.

The facts

Issued
May 14, 2003, 2:28 PM CDT (19:28 UTC)
Expired
May 14, 2003, 3:30 PM CDT
In force
62 min
Issued by
the Storm Prediction Center
All 24 counties

Attala County, MS, Carroll County, MS, Chickasaw County, MS, Choctaw County, MS, Clay County, MS, Holmes County, MS, Humphreys County, MS, Kemper County, MS, Lauderdale County, MS, Leake County, MS, Leflore County, MS, Madison County, MS, Montgomery County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Oktibbeha County, MS, Scott County, MS, Sharkey County, MS, Sunflower County, MS, Washington County, MS, Webster County, MS, Winston County, MS, Yazoo County, MS

The watches that followed

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

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 7.5 hours before the alert went out and 146 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, Jackson, MS at 12:00Z on 2003-05-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 56 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Jackson, MS at 12:00Z on 2003-05-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 205 square meters per square second.193958Sfc1 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
56 J/kg
Mixed-layer CIN
-185 J/kg
Mixed-layer LCL
564 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
205 m²/s²
0-3 km storm-relative helicity
241 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

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

249 
ACUS11 KWNS 141928
SWOMCD
SPC MCD 141928 
ALZ000-MSZ000-142030-

MESOSCALE DISCUSSION 0976
NWS STORM PREDICTION CENTER NORMAN OK
0228 PM CDT WED MAY 14 2003

AREAS AFFECTED...NRN  / CENTRAL MS...

CONCERNING...SEVERE THUNDERSTORM WATCH 368...

VALID 141928Z - 142030Z

THUNDERSTORMS CONTINUE TO MOVE EWD ACROSS ERN PORTIONS OF WW. 
SEVERE THREAT HAS REMAINED LOW...AND THUS WW MAY BE CANCELLED PRIOR
TO ITS SCHEDULED 14/22Z EXPIRATION.

LATEST RADAR IMAGERY SHOWS THUNDERSTORMS MOVING ACROSS ERN PORTIONS
OF WW ATTM...WITH SOME NEW CONVECTIVE DEVELOPMENT INVOF SRN PORTIONS
OF WW NEAR JAN.  BOUNDARY-LAYER AIRMASS HAS REMAINED STABLE ON THE
COOL SIDE OF NW-SE SURFACE FRONT OVER CENTRAL MS PRECLUDING A
WIDESPREAD SEVERE THREAT...BUT SOME DESTABILIZATION HAS OCCURRED ON
THE WARM SIDE OF BOUNDARY.  NONETHELESS...18Z JAN RAOB INDICATES
RELATIVELY WEAK INSTABILITY /AROUND 1000 J/KG MEAN-LAYER CAPE/ AND
MARGINAL DEEP-LAYER WIND FIELD...SUGGESTING THAT ANY FURTHER
THUNDERSTORM DEVELOPMENT SHOULD REMAIN MARGINALLY-SEVERE AT BEST. 
GIVEN CURRENT THINKING...WW MAY BE CANCELLED IN THE NEXT HOUR OR SO.

..GOSS.. 05/14/2003

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

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

34068891 33898850 31998845 32919099 33739096 33538996
34008891

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 14, 10:26 AM CDTMesoscale DiscussionSPCAttala, Bolivar, Calhoun, Carroll, Chickasaw, Choctaw and 28 more94 min
May 14, 11:10 AM CDTSevere Thunderstorm WatchSPCAttala, Bolivar, Calhoun, Carroll, Chickasaw, Choctaw and 26 more6 hr
May 14, 6:10 PM CDTSevere Thunderstorm WatchSPCClaiborne, Copiah, Covington, Hinds, Issaquena, Jefferson and 13 more6 hr

Nearby

Mesoscale Discussions in Mississippi, 2003Every mesoscale discussion in 2003

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.