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Watch Status Reports.
SEL4
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 494
NWS STORM PREDICTION CENTER NORMAN OK
1240 AM MDT TUE JUN 23 2009
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
WESTERN AND NORTH CENTRAL NEBRASKA
SOUTH CENTRAL SOUTH DAKOTA
EFFECTIVE THIS TUESDAY MORNING FROM 1240 AM UNTIL 700 AM MDT.
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 20 MILES WEST
SOUTHWEST OF ALLIANCE NEBRASKA TO 25 MILES EAST NORTHEAST OF
AINSWORTH NEBRASKA. FOR A COMPLETE DEPICTION OF THE WATCH SEE
THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).
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.
DISCUSSION...SMALL WRN NEB MCS EXPECTED TO CONTINUE GENERALLY
ENEWD...SUPPORTED BY UPLIFT OF MOIST LOW LVL ELY FLOW ATOP NE-MOVING
SYSTEM COLD POOL. WV IMAGERY SUGGESTS THAT MCS MAY BE
SUPPORTED...IN PART...BY ASCENT IN ENTRANCE REGION OF A NRN STREAM
JET STREAK. GIVEN DEEP EML ABOVE MOIST LAYER...FORWARD PROPAGATING
SEGMENTS/VERY SMALL BOWS MAY YIELD A FEW SPOTS OF HIGH
WIND/MARGINALLY SVR HAIL THROUGH LATER THIS MORNING /REF MCD 1280/.
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 25025.
...CORFIDI
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW4
WW 494 SEVERE TSTM NE SD 230640Z - 231300Z
AXIS..60 STATUTE MILES NORTH AND SOUTH OF LINE..
20WSW AIA/ALLIANCE NE/ - 25ENE ANW/AINSWORTH NE/
..AVIATION COORDS.. 50NM N/S /15ENE BFF - 22ENE ANW/
HAIL SURFACE AND ALOFT..1.5 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 500. MEAN STORM MOTION VECTOR 25025.
LAT...LON 42810316 43599952 41849952 41060316
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU4.
Watch 494 Status Report Messages:
STATUS REPORT #5 ON WW 494
VALID 231230Z - 231300Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 W BUB TO
45 WNW MHN TO 45 WNW VTN.
WW 494 WILL BE ALLOWED TO EXPIRE AT 13Z.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1284
..GUYER..06/23/09
ATTN...WFO...LBF...UNR...
&&
STATUS REPORT FOR WS 494
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
NEC009-015-017-031-071-089-103-115-149-183-231300-
NE
. NEBRASKA COUNTIES INCLUDED ARE
BLAINE BOYD BROWN
CHERRY GARFIELD HOLT
KEYA PAHA LOUP ROCK
WHEELER
$$
SDC095-121-123-231300-
SD
. SOUTH DAKOTA COUNTIES INCLUDED ARE
MELLETTE TODD TRIPP
$$
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.
$$
STATUS REPORT #4 ON WW 494
VALID 231125Z - 231240Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 WNW BBW
TO 35 ENE AIA TO 65 ENE CDR.
..GUYER..06/23/09
ATTN...WFO...LBF...UNR...
&&
STATUS REPORT FOR WS 494
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
NEC009-015-017-031-071-089-103-115-149-183-231240-
NE
. NEBRASKA COUNTIES INCLUDED ARE
BLAINE BOYD BROWN
CHERRY GARFIELD HOLT
KEYA PAHA LOUP ROCK
WHEELER
$$
SDC007-071-095-121-123-231240-
SD
. SOUTH DAKOTA COUNTIES INCLUDED ARE
BENNETT JACKSON MELLETTE
TODD TRIPP
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #3 ON WW 494
VALID 231040Z - 231140Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1283
..GUYER..06/23/09
ATTN...WFO...LBF...UNR...
&&
STATUS REPORT FOR WS 494
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
NEC005-009-017-031-049-069-075-091-103-113-117-161-171-231140-
NE
. NEBRASKA COUNTIES INCLUDED ARE
ARTHUR BLAINE BROWN
CHERRY DEUEL GARDEN
GRANT HOOKER KEYA PAHA
LOGAN MCPHERSON SHERIDAN
THOMAS
$$
SDC007-071-095-121-123-231140-
SD
. SOUTH DAKOTA COUNTIES INCLUDED ARE
BENNETT JACKSON MELLETTE
TODD TRIPP
$$
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.
$$
STATUS REPORT #2 ON WW 494
VALID 230925Z - 231040Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1281
..GUYER..06/23/09
ATTN...WFO...LBF...UNR...
&&
STATUS REPORT FOR WS 494
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
NEC005-009-017-031-049-069-075-091-103-113-117-161-171-231040-
NE
. NEBRASKA COUNTIES INCLUDED ARE
ARTHUR BLAINE BROWN
CHERRY DEUEL GARDEN
GRANT HOOKER KEYA PAHA
LOGAN MCPHERSON SHERIDAN
THOMAS
$$
SDC007-071-095-121-123-231040-
SD
. SOUTH DAKOTA COUNTIES INCLUDED ARE
BENNETT JACKSON MELLETTE
TODD TRIPP
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #1 ON WW 494
VALID 230750Z - 230840Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..GUYER..06/23/09
ATTN...WFO...LBF...UNR...
&&
STATUS REPORT FOR WS 494
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
NEC005-009-017-031-049-069-075-091-103-113-117-161-171-230840-
NE
. NEBRASKA COUNTIES INCLUDED ARE
ARTHUR BLAINE BROWN
CHERRY DEUEL GARDEN
GRANT HOOKER KEYA PAHA
LOGAN MCPHERSON SHERIDAN
THOMAS
$$
SDC007-121-123-230840-
SD
. SOUTH DAKOTA COUNTIES INCLUDED ARE
BENNETT TODD TRIPP
$$
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
|
Low (20%)
|
Probability
of 1 or
more hailstones > 2 inches
|
Low (<5%)
|
Combined Severe Hail/Wind
Probability of 6 or more combined severe hail/wind events
|
Mod (50%)
|
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 
