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The expiration time in the watch graphic is amended if the watch is
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Watch Status Reports.
SEL2
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 842
NWS STORM PREDICTION CENTER NORMAN OK
130 PM MDT TUE AUG 19 2008
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
WESTERN AND CENTRAL MONTANA
EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 130 PM UNTIL
800 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 55
STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES NORTHEAST OF
CUT BANK MONTANA TO 15 MILES SOUTH SOUTHEAST OF BUTTE MONTANA.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU2).
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 841...
DISCUSSION...SCATTERED THUNDERSTORMS HAVE BEGUN TO FORM AHEAD OF
UPPER TROUGH MOVING INTO WESTERN MT. THESE STORMS WILL SPREAD
NORTHEASTWARD THROUGH THE AFTERNOON AND EARLY EVENING ACROSS THE
WATCH AREA. DESPITE LIMITED LOW LEVEL MOISTURE...STEEP LAPSE RATES
AND INCREASING WINDS ALOFT WILL POSE A RISK OF ISOLATED SEVERE
STORMS CAPABLE OF LARGE HAIL AND DAMAGING WINDS.
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 450. MEAN STORM
MOTION VECTOR 22030.
...HART
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW2
WW 842 SEVERE TSTM MT 191930Z - 200200Z
AXIS..55 STATUTE MILES EAST AND WEST OF LINE..
40NE CTB/CUT BANK MT/ - 15SSE BTM/BUTTE MT/
..AVIATION COORDS.. 50NM E/W /55SE YQL - 31NNE DLN/
HAIL SURFACE AND ALOFT..2 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 450. MEAN STORM MOTION VECTOR 22030.
LAT...LON 49021054 45741123 45741351 49021297
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU2.
Watch 842 Status Report Messages:
STATUS REPORT #5 ON WW 842
VALID 200040Z - 200140Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 SSE BTM
TO 30 NNW 3DU.
BUT...THE THREAT IS DIMINISHING OR BECOMING MORE HIGHLY
LOCALIZED... AND REMAINING VALID PORTION OF THE WW MAY BE CANCELLED
EARLY.
..KERR..08/20/08
ATTN...WFO...TFX...MSO...
&&
STATUS REPORT FOR WS 842
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC007-013-015-035-041-043-049-051-059-073-099-101-200140-
MT
. MONTANA COUNTIES INCLUDED ARE
BROADWATER CASCADE CHOUTEAU
GLACIER HILL JEFFERSON
LEWIS AND CLARK LIBERTY MEAGHER
PONDERA TETON TOOLE
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #4 ON WW 842
VALID 192340Z - 200040Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 SSE BTM
TO 30 NNW 3DU.
..KERR..08/19/08
ATTN...WFO...TFX...MSO...
&&
STATUS REPORT FOR WS 842
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC007-013-015-035-041-043-049-051-059-073-099-101-200040-
MT
. MONTANA COUNTIES INCLUDED ARE
BROADWATER CASCADE CHOUTEAU
GLACIER HILL JEFFERSON
LEWIS AND CLARK LIBERTY MEAGHER
PONDERA TETON TOOLE
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #3 ON WW 842
VALID 192235Z - 192340Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..KERR..08/19/08
ATTN...WFO...TFX...MSO...
&&
STATUS REPORT FOR WS 842
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC007-013-015-023-035-039-041-043-049-051-059-073-077-093-099-
101-192340-
MT
. MONTANA COUNTIES INCLUDED ARE
BROADWATER CASCADE CHOUTEAU
DEER LODGE GLACIER GRANITE
HILL JEFFERSON LEWIS AND CLARK
LIBERTY MEAGHER PONDERA
POWELL SILVER BOW TETON
TOOLE
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #2 ON WW 842
VALID 192130Z - 192240Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..KERR..08/19/08
ATTN...WFO...TFX...MSO...
&&
STATUS REPORT FOR WS 842
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC007-013-015-023-035-039-041-043-049-051-059-073-077-093-099-
101-192240-
MT
. MONTANA COUNTIES INCLUDED ARE
BROADWATER CASCADE CHOUTEAU
DEER LODGE GLACIER GRANITE
HILL JEFFERSON LEWIS AND CLARK
LIBERTY MEAGHER PONDERA
POWELL SILVER BOW TETON
TOOLE
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #1 ON WW 842
VALID 192030Z - 192140Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..MEAD..08/19/08
ATTN...WFO...TFX...MSO...
&&
STATUS REPORT FOR WS 842
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC007-013-015-023-035-039-041-043-049-051-059-073-077-093-099-
101-192140-
MT
. MONTANA COUNTIES INCLUDED ARE
BROADWATER CASCADE CHOUTEAU
DEER LODGE GLACIER GRANITE
HILL JEFFERSON LEWIS AND CLARK
LIBERTY MEAGHER PONDERA
POWELL SILVER BOW TETON
TOOLE
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
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 (30%)
|
Probability of 1 or more wind events > 65 knots
|
Mod (30%)
|
Hail
Probability of 10 or more severe hail events
|
Mod (30%)
|
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 (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.
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