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Watch Status Reports.
SEL8
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 668
NWS STORM PREDICTION CENTER NORMAN OK
300 PM MDT THU AUG 6 2009
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
SOUTH CENTRAL MONTANA
NORTHWEST WYOMING
EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 300 PM UNTIL
1000 PM MDT.
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 60
STATUTE MILES EAST AND WEST OF A LINE FROM 55 MILES EAST
NORTHEAST OF HARLOWTON MONTANA TO 50 MILES EAST OF JACKSON
WYOMING. 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 666...WW 667...
DISCUSSION...STRONG SEVERE STORMS HAVE DEVELOPED IN A BAND FROM
EXTREME SERN ID NNEWD INTO SRN MT. THIS ACTIVITY IS AHEAD OF A
STRONG UPPER LOW MOVING ENEWD INTO THE GREAT BASIN...AND INCREASING
DYNAMIC FORCING IS FORECAST TO SPREAD DOWNSTREAM TOWARD THE NRN
ROCKIES THIS EVENING. LOW LEVEL MOISTURE WITH SURFACE DEW POINTS IN
THE UPPER 50S IS CONTRIBUTING TO MLCAPE OF 1000-1500 J/KG...AND
WSWLY MID LEVEL WINDS OF 40-45 KT ARE RESULTING IN DEEP LAYER SHEAR
SUPPORTIVE OF SEVERE STORMS INCLUDING ISOLATED SUPERCELLS. LARGE
HAIL AND DAMAGING WINDS WILL BE POSSIBLE WITH STRONGER STORMS.
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 500. MEAN STORM
MOTION VECTOR 24030.
...WEISS
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW8
WW 668 SEVERE TSTM MT WY 062100Z - 070400Z
AXIS..60 STATUTE MILES EAST AND WEST OF LINE..
55ENE 3HT/HARLOWTON MT/ - 50E JAC/JACKSON WY/
..AVIATION COORDS.. 50NM E/W /40ESE LWT - 43E JAC/
HAIL SURFACE AND ALOFT..2 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 500. MEAN STORM MOTION VECTOR 24030.
LAT...LON 46720748 43590852 43591093 46721001
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU8.
Watch 668 Status Report Messages:
STATUS REPORT #6 ON WW 668
VALID 070230Z - 070340Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 55 WNW SHR
TO 55 ESE LVM TO 30 NE LVM TO 20 SW 3HT.
..MEAD..08/07/09
ATTN...WFO...BYZ...RIW...
&&
STATUS REPORT FOR WS 668
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC003-009-037-065-095-097-103-107-111-070340-
MT
. MONTANA COUNTIES INCLUDED ARE
BIG HORN CARBON GOLDEN VALLEY
MUSSELSHELL STILLWATER SWEET GRASS
TREASURE WHEATLAND YELLOWSTONE
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #5 ON WW 668
VALID 070140Z - 070240Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 55 ENE COD
TO 45 NW COD TO 40 NE WEY.
..MEAD..08/07/09
ATTN...WFO...BYZ...RIW...
&&
STATUS REPORT FOR WS 668
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC003-009-037-065-067-095-097-103-107-111-070240-
MT
. MONTANA COUNTIES INCLUDED ARE
BIG HORN CARBON GOLDEN VALLEY
MUSSELSHELL PARK STILLWATER
SWEET GRASS TREASURE WHEATLAND
YELLOWSTONE
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #4 ON WW 668
VALID 070035Z - 070140Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 55 WNW SHR
TO 40 NE COD TO 30 WNW WRL TO 50 SSW COD TO 35 ENE JAC TO 25 NNW
JAC.
..MEAD..08/07/09
ATTN...WFO...BYZ...RIW...
&&
STATUS REPORT FOR WS 668
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC003-009-037-065-067-095-097-103-107-111-070140-
MT
. MONTANA COUNTIES INCLUDED ARE
BIG HORN CARBON GOLDEN VALLEY
MUSSELSHELL PARK STILLWATER
SWEET GRASS TREASURE WHEATLAND
YELLOWSTONE
$$
WYC029-039-070140-
WY
. WYOMING COUNTIES INCLUDED ARE
PARK TETON
$$
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.
$$
STATUS REPORT #3 ON WW 668
VALID 062345Z - 070040Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..MEAD..08/06/09
ATTN...WFO...BYZ...RIW...
&&
STATUS REPORT FOR WS 668
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC003-009-037-065-067-095-097-103-107-111-070040-
MT
. MONTANA COUNTIES INCLUDED ARE
BIG HORN CARBON GOLDEN VALLEY
MUSSELSHELL PARK STILLWATER
SWEET GRASS TREASURE WHEATLAND
YELLOWSTONE
$$
WYC029-039-070040-
WY
. WYOMING COUNTIES INCLUDED ARE
PARK TETON
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #2 ON WW 668
VALID 062225Z - 062340Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..JEWELL..08/06/09
ATTN...WFO...BYZ...RIW...
&&
STATUS REPORT FOR WS 668
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC003-009-037-065-067-095-097-103-107-111-062340-
MT
. MONTANA COUNTIES INCLUDED ARE
BIG HORN CARBON GOLDEN VALLEY
MUSSELSHELL PARK STILLWATER
SWEET GRASS TREASURE WHEATLAND
YELLOWSTONE
$$
WYC029-039-062340-
WY
. WYOMING COUNTIES INCLUDED ARE
PARK TETON
$$
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.
$$
STATUS REPORT #1 ON WW 668
VALID 062135Z - 062240Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..MEAD..08/06/09
ATTN...WFO...BYZ...RIW...
&&
STATUS REPORT FOR WS 668
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC003-009-037-065-067-095-097-103-107-111-062240-
MT
. MONTANA COUNTIES INCLUDED ARE
BIG HORN CARBON GOLDEN VALLEY
MUSSELSHELL PARK STILLWATER
SWEET GRASS TREASURE WHEATLAND
YELLOWSTONE
$$
WYC029-039-062240-
WY
. WYOMING COUNTIES INCLUDED ARE
PARK TETON
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
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 (40%)
|
Probability of 1 or more wind events > 65 knots
|
Low (20%)
|
Hail
Probability of 10 or more severe hail events
|
Mod (30%)
|
Probability
of 1 or
more hailstones > 2 inches
|
Low (10%)
|
Combined Severe Hail/Wind
Probability of 6 or more combined severe hail/wind events
|
Mod (60%)
|
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 
