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The expiration time in the watch graphic is amended if the watch is
replaced, cancelled or extended.
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Watch Status Reports.
SEL1
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 231
NWS STORM PREDICTION CENTER NORMAN OK
510 AM CDT SUN MAY 3 2009
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
CENTRAL AND NORTHERN LOUISIANA
EASTERN TEXAS
EFFECTIVE THIS SUNDAY MORNING FROM 510 AM UNTIL 1100 AM CDT.
HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 105
STATUTE MILES EAST AND WEST OF A LINE FROM 45 MILES SOUTHEAST OF
HUNTSVILLE TEXAS TO 30 MILES NORTH OF SHREVEPORT LOUISIANA. FOR
A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU1).
REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR 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. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.
DISCUSSION...SMALL LINE OF ELEVATED TSTMS OVER CENTRAL TX AT 10Z IS
MOVING EWD AT NEAR 50 KT AND SHOULD BEGIN INGESTING RICHER GULF
MOISTURE AS IT OVERSPREADS WARM SECTOR WITHIN THE HOUR OVER ERN TX.
AIR MASS REMAINS MODERATELY UNSTABLE WITHIN WARM SECTOR...WITH WEAK
CAPPING...AHEAD OF POTENT SHORTWAVE TROUGH EJECTING ACROSS TX.
STORMS MAY EVOLVE INTO A BOW ECHO AND RACE EWD INVOF STALLED SURFACE
OUTFLOW BOUNDARY/FRONT EXTENDING ACROSS ERN TX AND CENTRAL LA
THROUGH THE MORNING...WITH EVENTUAL BACKBUILDING ALONG COMPOSITE
OUTFLOW INTO SERN TX. MARGINALLY SEVERE HAIL MAY ACCOMPANY ELEVATED
STORMS...ALTHOUGH WIND DAMAGE MAY BECOME PARAMOUNT AS STORMS ROOT
NEARER THE SURFACE THROUGH THE MORNING.
AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 26040.
...EVANS
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW1
WW 231 SEVERE TSTM LA TX 031010Z - 031600Z
AXIS..105 STATUTE MILES EAST AND WEST OF LINE..
45SE UTS/HUNTSVILLE TX/ - 30N SHV/SHREVEPORT LA/
..AVIATION COORDS.. 90NM E/W /28NE IAH - 7N EIC/
HAIL SURFACE AND ALOFT..1.5 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 500. MEAN STORM MOTION VECTOR 26040.
LAT...LON 30269669 32869563 32869201 30269318
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU1.
Watch 231 Status Report Messages:
STATUS REPORT #2 ON WW 231
VALID 031450Z - 031540Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 WNW CLL
TO 20 N UTS TO 25 WSW ESF.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 686
..SPC..05/03/09
ATTN...WFO...LCH...SHV...FWD...HGX...
&&
STATUS REPORT FOR WS 231
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
LAC011-079-115-031540-
LA
. LOUISIANA PARISHES INCLUDED ARE
BEAUREGARD RAPIDES VERNON
$$
TXC199-241-351-373-407-455-457-031540-
TX
. TEXAS COUNTIES INCLUDED ARE
HARDIN JASPER NEWTON
POLK SAN JACINTO TRINITY
TYLER
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #1 ON WW 231
VALID 031145Z - 031240Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 SSW CLL
TO 15 N UTS TO 35 NNW LFK TO 10 N GGG TO 40 N GGG.
FOR ADDITIONAL INFORMATION SEE UPCOMING SPC MESOSCALE DISCUSSION
684.
..EDWARDS..05/03/09
ATTN...WFO...LCH...SHV...FWD...HGX...
&&
STATUS REPORT FOR WS 231
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
LAC011-013-015-017-021-027-031-043-049-059-061-069-073-079-081-
085-111-115-119-127-031240-
LA
. LOUISIANA PARISHES INCLUDED ARE
BEAUREGARD BIENVILLE BOSSIER
CADDO CALDWELL CLAIBORNE
DE SOTO GRANT JACKSON
LA SALLE LINCOLN NATCHITOCHES
OUACHITA RAPIDES RED RIVER
SABINE UNION VERNON
WEBSTER WINN
$$
TXC005-073-183-185-199-203-225-241-291-315-339-347-351-365-373-
401-403-405-407-419-455-457-459-471-031240-
TX
. TEXAS COUNTIES INCLUDED ARE
ANGELINA CHEROKEE GREGG
GRIMES HARDIN HARRISON
HOUSTON JASPER LIBERTY
MARION MONTGOMERY NACOGDOCHES
NEWTON PANOLA POLK
RUSK SABINE SAN AUGUSTINE
SAN JACINTO SHELBY TRINITY
TYLER UPSHUR WALKER
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
Note:
Click for Complete Product Text.
Tornadoes
Probability of 2 or more tornadoes
|
Low (20%)
|
Probability of 1 or more strong (F2-F5) tornadoes
|
Low (5%)
|
Wind
Probability of 10 or more severe wind events
|
Mod (50%)
|
Probability of 1 or more wind events > 65 knots
|
Mod (30%)
|
Hail
Probability of 10 or more severe hail events
|
Mod (50%)
|
Probability
of 1 or
more hailstones > 2 inches
|
Low (20%)
|
Combined Severe Hail/Wind
Probability of 6 or more combined severe hail/wind events
|
High (80%)
|
For each watch, probabilities for particular events inside the watch
(listed above in each table) are determined by the issuing forecaster.
The "Low" category contains probability values ranging from less than 2%
to 20% (F2-F5 tornadoes), less than 5% to 20% (all other probabilities),
"Moderate" from 30% to 60%, and "High" from 70% to greater than 95%.
High values are bolded and lighter in color to provide awareness of
an increased threat for a particular event.
weather.gov 
