Tornado Watch 898

Issued

Dec 22, 2011, 4:36 AM CST (10:36 UTC)

Expired

Dec 22, 2011, 12:05 PM CST

In force

7 hr

Issued by

the Storm Prediction Center

Largest hail expected

0.5 in

Strongest gust expected

60 kt

The Jackson/Brandon,MS radar (KDGX), 89 km from the middle of the area, began a volume at 10:37 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.

Two or more tornadoes

30%

One or more EF2 to EF5 tornadoes

20%

Ten or more severe wind reports

50%

One or more gusts of 65 knots or more

30%

Ten or more severe hail reports

10%

One or more hailstones of 2 inches or more

5%

Six or more combined severe hail and wind reports

90%

• Mesoscale Discussion 2387Dec 22, 4:11 AM CST
• Mesoscale Discussion 2388Dec 22, 7:50 AM CST

546 
WWUS20 KWNS 221041
SEL8
SPC WW 221041
LAZ000-MSZ000-CWZ000-221900-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 898
NWS STORM PREDICTION CENTER NORMAN OK
435 AM CST THU DEC 22 2011

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

       CENTRAL AND EASTERN LOUISIANA
       SOUTHERN AND CENTRAL MISSISSIPPI
       COASTAL WATERS

EFFECTIVE THIS THURSDAY MORNING AND AFTERNOON FROM 435 AM UNTIL
100 PM CST.

TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 80 STATUTE
MILES EAST AND WEST OF A LINE FROM 90 MILES NORTH NORTHEAST OF
JACKSON MISSISSIPPI TO 20 MILES SOUTH OF INTRACOASTAL CITY
LOUISIANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

DISCUSSION...SSW-NNE SQLN NOW EVOLVING OVER THE SABINE RVR VLY
EXPECTED TO INCREASE IN EXTENT AND POSSIBLY INTENSITY AS THE LINE
CONTINUES EWD INTO REGION OF RAPID LOW LVL MOISTENING/WARMING AHEAD
OF TX SHORTWAVE TROUGH.  WELL-DEFINED JET EXIT REGION FORMING IN
RESPONSE TO AMPLIFICATION OF THE DOWNSTREAM UPR RDG WILL ENHANCE
LARGE SCALE ASCENT OVER LA/MS.  THIS MAY FOSTER DEVELOPMENT OF
ADDITIONAL STORMS AHEAD OF THE SQLN IN CONFLUENT LOW LVL SSWLY FLOW.
STRENGTHENING WIND FIELD WILL SUPPORT EMBEDDED SUPERCELLS/LEWPS
WITHIN SQLN LINE...WITH AN ATTENDANT RISK FOR DMGG WIND/ISOLD
TORNADOES.  ISOLD TORNADOES ALSO WILL BE POSSIBLE WITH ANY STORMS
THAT FORM AHEAD OF SQLN.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
400. MEAN STORM MOTION VECTOR 21040.


...CORFIDI

Tornado Watches in Mississippi, 2011Tornado Watches in Louisiana, 2011Every tornado watch in 2011

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.