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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.
SEL8
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 298
NWS STORM PREDICTION CENTER NORMAN OK
940 PM CDT WED MAY 13 2009
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
NORTHWEST ARKANSAS
SOUTHERN AND EASTERN OKLAHOMA
A SMALL PART OF NORTHWEST TEXAS
EFFECTIVE THIS WEDNESDAY NIGHT AND THURSDAY MORNING FROM 940 PM
UNTIL 400 AM CDT.
HAIL TO 2 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 30 MILES NORTHWEST OF
HARRISON ARKANSAS TO 35 MILES WEST SOUTHWEST OF ARDMORE OKLAHOMA.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU8).
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.
OTHER WATCH INFORMATION...CONTINUE...WW 293...WW 295...WW
296...WW 297...
DISCUSSION...A BROKEN BAND OF SEVERE STORMS...WITH SOME EMBEDDED
SUPERCELLS...CONTINUES TO DEVELOP SWD/SEWD ALONG THE COLD FRONT
ACROSS OK. DESPITE THE LOSS OF DAYTIME HEATING...STRONG INSTABILITY
AND PRONOUNCED CONVERGENCE/LOW-LEVEL FRONTOGENESIS WILL HELP
MAINTAIN EXISTING STORMS AND SUPPORT NEW DEVELOPMENT FOR THE NEXT
SEVERAL HOURS. LARGE HAIL CAN BE EXPECTED WITH THE STRONGEST
STORMS...WHILE THE DAMAGING WIND THREAT SHOULD INCREASE SOME AS A
RESULT OF STORM MERGERS/INTERACTIONS AND SUBSEQUENT COLD POOL AND
SMALL BOW ECHO FORMATION.
AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM
MOTION VECTOR 32020.
...THOMPSON
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW8
WW 298 SEVERE TSTM AR OK TX 140240Z - 140900Z
AXIS..105 STATUTE MILES EAST AND WEST OF LINE..
30NW HRO/HARRISON AR/ - 35WSW ADM/ARDMORE OK/
..AVIATION COORDS.. 90NM E/W /35NE RZC - 22WSW ADM/
HAIL SURFACE AND ALOFT..2 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 550. MEAN STORM MOTION VECTOR 32020.
LAT...LON 36569163 34089575 34089941 36569541
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU8.
Watch 298 Status Report Messages:
STATUS REPORT #1 ON WW 298
VALID 140740Z - 140840Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 NE FSI TO
35 NW ADM TO 35 NNW PRX.
..SPC..05/14/09
ATTN...WFO...LZK...TSA...OUN...
&&
STATUS REPORT FOR WS 298
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
OKC013-019-023-031-033-067-069-085-095-099-127-137-140840-
OK
. OKLAHOMA COUNTIES INCLUDED ARE
BRYAN CARTER CHOCTAW
COMANCHE COTTON JEFFERSON
JOHNSTON LOVE MARSHALL
MURRAY PUSHMATAHA STEPHENS
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
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 (40%)
|
Hail
Probability of 10 or more severe hail events
|
High (70%)
|
Probability
of 1 or
more hailstones > 2 inches
|
Mod (40%)
|
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.
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