Note:
The expiration time in the watch graphic is amended if the watch is
replaced, cancelled or extended.
Note: Click for
Watch Status Reports.
SEL7
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 357
NWS STORM PREDICTION CENTER NORMAN OK
155 PM CDT SUN JUN 20 2010
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
PARTS OF SOUTHERN MONTANA
PARTS OF CENTRAL AND NORTHERN WYOMING
EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 155 PM UNTIL 800
PM 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 60
STATUTE MILES EAST AND WEST OF A LINE FROM 50 MILES EAST
SOUTHEAST OF LANDER WYOMING TO 55 MILES EAST NORTHEAST OF
HARLOWTON MONTANA. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU7).
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 356...
DISCUSSION...THUNDERSTORMS WILL INCREASE IN NUMBER AND INTENSITY
WITH CONTINUED HEATING OF A MODERATELY UNSTABLE AIR MASS ACROSS THE
WATCH AREA. INITIAL STORMS OVER HIGHER TERRAIN BUT WITH STEEP LAPSE
RATES AND APPROACH OF UPPER S/WV FROM THE SW...STRONGER/SEVERE
STORMS WILL DEVELOP ACROSS THE WATCH WITH LARGE HAIL AND LOCAL
DAMAGING WINDS THE PRIMARY THREAT.
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 23025.
...HALES
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW7
WW 357 SEVERE TSTM MT WY 201855Z - 210100Z
AXIS..60 STATUTE MILES EAST AND WEST OF LINE..
50ESE LND/LANDER WY/ - 55ENE 3HT/HARLOWTON MT/
..AVIATION COORDS.. 50NM E/W /59SSE BOY - 40ESE LWT/
HAIL SURFACE AND ALOFT..2 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 450. MEAN STORM MOTION VECTOR 23025.
LAT...LON 42520900 46721001 46720748 42520663
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU7.
Watch 357 Status Report Messages:
STATUS REPORT #4 ON WW 357
VALID 210030Z - 210140Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 60 N CPR TO
30 WSW LWT.
..HURLBUT..06/21/10
ATTN...WFO...BYZ...RIW...
&&
STATUS REPORT FOR WS 357
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC003-017-065-075-087-103-111-210140-
MT
. MONTANA COUNTIES INCLUDED ARE
BIG HORN CUSTER MUSSELSHELL
POWDER RIVER ROSEBUD TREASURE
YELLOWSTONE
$$
WYC019-033-210140-
WY
. WYOMING COUNTIES INCLUDED ARE
JOHNSON SHERIDAN
$$
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.
$$
STATUS REPORT #3 ON WW 357
VALID 202330Z - 210040Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 NE CPR TO
55 NW LND.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1042
..HURLBUT..06/20/10
ATTN...WFO...BYZ...RIW...
&&
STATUS REPORT FOR WS 357
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC003-009-017-065-075-087-103-111-210040-
MT
. MONTANA COUNTIES INCLUDED ARE
BIG HORN CARBON CUSTER
MUSSELSHELL POWDER RIVER ROSEBUD
TREASURE YELLOWSTONE
$$
WYC003-017-019-029-033-043-210040-
WY
. WYOMING COUNTIES INCLUDED ARE
BIG HORN HOT SPRINGS JOHNSON
PARK SHERIDAN WASHAKIE
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #2 ON WW 357
VALID 202145Z - 202240Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..HURLBUT..06/20/10
ATTN...WFO...BYZ...RIW...
&&
STATUS REPORT FOR WS 357
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC003-009-017-065-075-087-103-111-202240-
MT
. MONTANA COUNTIES INCLUDED ARE
BIG HORN CARBON CUSTER
MUSSELSHELL POWDER RIVER ROSEBUD
TREASURE YELLOWSTONE
$$
WYC003-013-017-019-025-029-033-043-202240-
WY
. WYOMING COUNTIES INCLUDED ARE
BIG HORN FREMONT HOT SPRINGS
JOHNSON NATRONA PARK
SHERIDAN WASHAKIE
$$
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.
$$
STATUS REPORT #1 ON WW 357
VALID 202020Z - 202140Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..STOPPKOTTE..06/20/10
ATTN...WFO...BYZ...RIW...
&&
STATUS REPORT FOR WS 357
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC003-009-017-065-075-087-103-111-202140-
MT
. MONTANA COUNTIES INCLUDED ARE
BIG HORN CARBON CUSTER
MUSSELSHELL POWDER RIVER ROSEBUD
TREASURE YELLOWSTONE
$$
WYC003-013-017-019-025-029-033-043-202140-
WY
. WYOMING COUNTIES INCLUDED ARE
BIG HORN FREMONT HOT SPRINGS
JOHNSON NATRONA PARK
SHERIDAN WASHAKIE
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
Note:
Click for Complete Product Text.
Tornadoes
Probability of 2 or more tornadoes
|
Low (10%)
|
Probability of 1 or more strong (F2-F5) tornadoes
|
Low (<2%)
|
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.