Note:
The expiration time in the watch graphic is amended if the watch is
replaced, cancelled or extended.
Note: Click for
Watch Status Reports.
SEL0
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 600
NWS STORM PREDICTION CENTER NORMAN OK
1120 PM CDT FRI JUL 17 2009
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
SOUTHWEST TEXAS
EFFECTIVE THIS FRIDAY NIGHT AND SATURDAY MORNING FROM 1120 PM
UNTIL 400 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 60
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 50 MILES NORTH OF
MARFA TEXAS TO 80 MILES SOUTHEAST OF MIDLAND TEXAS. FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU0).
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 599...
DISCUSSION...NEW THUNDERSTORMS HAVE RAPIDLY DEVELOPED ALONG OUTFLOW
BOUNDARY MOVING SWD INTO THE PERMIAN BASIN. THIS IS EXPECTED TO
REINFORCE COLD POOL PRODUCTION BEHIND THE GUST FRONT...WHICH IS
EXPECTED TO PROGRESS SWD INTO THE EARLY MORNING HOURS WITH A
CONTINUED THREAT FOR DAMAGING WND GUSTS.
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 32025.
...WEISS
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW0
WW 600 SEVERE TSTM TX 180420Z - 180900Z
AXIS..60 STATUTE MILES NORTH AND SOUTH OF LINE..
50N MRF/MARFA TX/ - 80SE MAF/MIDLAND TX/
..AVIATION COORDS.. 50NM N/S /48N MRF - 43WSW SJT/
HAIL SURFACE AND ALOFT..1.5 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 500. MEAN STORM MOTION VECTOR 32025.
LAT...LON 31950401 32000123 30260123 30220401
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU0.
Watch 600 Status Report Messages:
STATUS REPORT #1 ON WW 600
VALID 180645Z - 180740Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 SSE CNM
TO 5 SSE INK TO 20 SE MAF TO 10 SSW BGS.
..BROYLES..07/18/09
ATTN...WFO...MAF...SJT...
&&
STATUS REPORT FOR WS 600
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
TXC103-105-173-371-383-389-443-461-475-180740-
TX
. TEXAS COUNTIES INCLUDED ARE
CRANE CROCKETT GLASSCOCK
PECOS REAGAN REEVES
TERRELL UPTON WARD
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
Note:
Click for Complete Product Text.
Tornadoes
Probability of 2 or more tornadoes
|
Low (<5%)
|
Probability of 1 or more strong (F2-F5) tornadoes
|
Low (5%)
|
Wind
Probability of 10 or more severe wind events
|
Mod (40%)
|
Probability of 1 or more wind events > 65 knots
|
Low (20%)
|
Hail
Probability of 10 or more severe hail events
|
Low (10%)
|
Probability
of 1 or
more hailstones > 2 inches
|
Low (10%)
|
Combined Severe Hail/Wind
Probability of 6 or more combined severe hail/wind events
|
High (70%)
|
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 
