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 457
NWS STORM PREDICTION CENTER NORMAN OK
415 AM CDT THU JUN 18 2009
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
CENTRAL ILLINOIS
EFFECTIVE THIS THURSDAY MORNING FROM 415 AM UNTIL 1000 AM CDT.
HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 55
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 40 MILES WEST
SOUTHWEST OF PEORIA ILLINOIS TO 30 MILES SOUTH OF DANVILLE
ILLINOIS. 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 454...WW 455...WW 456...
DISCUSSION...MULTIPLE CLUSTERS OF INTENSE THUNDERSTORMS OVER
SOUTHEAST IA AND WESTERN IL WILL LIKELY MAINTAIN INTENSITY AS IT
TRACKS ACROSS CENTRAL IL. STORMS ARE ALONG THE GRADIENT OF A VERY
UNSTABLE AIRMASS...WITH ACTIVITY MOVING AT OVER 40 KNOTS. DAMAGING
WINDS APPEAR TO BE THE MAIN THREAT.
AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM
MOTION VECTOR 26040.
...HART
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW7
WW 457 SEVERE TSTM IL 180915Z - 181500Z
AXIS..55 STATUTE MILES NORTH AND SOUTH OF LINE..
40WSW PIA/PEORIA IL/ - 30S DNV/DANVILLE IL/
..AVIATION COORDS.. 50NM N/S /55NE UIN - 23NW TTH/
HAIL SURFACE AND ALOFT..2 INCHES. WIND GUSTS..70 KNOTS.
MAX TOPS TO 500. MEAN STORM MOTION VECTOR 26040.
LAT...LON 41249037 40568759 38978759 39659037
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU7.
Watch 457 Status Report Messages:
STATUS REPORT #2 ON WW 457
VALID 181150Z - 181240Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 W SPI TO
15 ENE SPI TO 30 NNE CMI TO 30 NNW DNV.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1199
..CARBIN..06/18/09
ATTN...WFO...ILX...LOT...
&&
STATUS REPORT FOR WS 457
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
ILC019-021-023-025-029-033-035-041-045-049-079-101-115-139-147-
159-167-173-183-181240-
IL
. ILLINOIS COUNTIES INCLUDED ARE
CHAMPAIGN CHRISTIAN CLARK
CLAY COLES CRAWFORD
CUMBERLAND DOUGLAS EDGAR
EFFINGHAM JASPER LAWRENCE
MACON MOULTRIE PIATT
RICHLAND SANGAMON SHELBY
VERMILION
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #1 ON WW 457
VALID 181050Z - 181140Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 WSW PIA
TO 15 SW BMI TO 30 N BMI.
..CARBIN..06/18/09
ATTN...WFO...ILX...LOT...
&&
STATUS REPORT FOR WS 457
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
ILC017-019-021-023-029-035-039-041-045-053-057-107-113-115-125-
129-139-147-167-169-173-183-181140-
IL
. ILLINOIS COUNTIES INCLUDED ARE
CASS CHAMPAIGN CHRISTIAN
CLARK COLES CUMBERLAND
DE WITT DOUGLAS EDGAR
FORD FULTON LOGAN
MCLEAN MACON MASON
MENARD MOULTRIE PIATT
SANGAMON SCHUYLER SHELBY
VERMILION
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
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 (50%)
|
Probability of 1 or more wind events > 65 knots
|
Mod (40%)
|
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
|
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 
