Note:
The expiration time in the watch graphic is amended if the watch is
replaced, cancelled or extended.
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Watch Status Reports.
SEL3
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 393
NWS STORM PREDICTION CENTER NORMAN OK
755 AM CDT FRI MAY 30 2008
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
SOUTHEASTERN IOWA
WESTERN AND NORTHERN ILLINOIS
NORTHEASTERN MISSOURI
LAKE MICHIGAN
EFFECTIVE THIS FRIDAY MORNING AND AFTERNOON FROM 755 AM UNTIL 200
PM CDT.
TORNADOES...HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 90 STATUTE
MILES EAST AND WEST OF A LINE FROM 30 MILES SOUTH SOUTHWEST OF
QUINCY ILLINOIS TO 25 MILES NORTHWEST OF MARSEILLES ILLINOIS.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU3).
REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND 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.
OTHER WATCH INFORMATION...THIS TORNADO WATCH REPLACES TORNADO
WATCH NUMBER 392. WATCH NUMBER 392 WILL NOT BE IN EFFECT AFTER
755 AM CDT.
DISCUSSION...AIR MASS FCST TO DESTABILIZE THROUGHOUT REMAINDER
MORNING AHEAD OF EXISTING MCS MOVING EWD OUT OF SERN IA/NRN MO
REGION. WELL DEFINED OUTFLOW BOUNDARY FROM CHICAGO METRO WSWWD
ACROSS NRN IL MAY PROVIDE ENHANCED LOW LEVEL
ASCENT/SRH/VORTICITY...AND MAY LIFT NWD SLIGHTLY DURING LATE MORNING
HOURS AHEAD OF CONVECTION. DEEP-LAYER SHEAR AND INCREASING BOUNDARY
LAYER THETAE WILL FAVOR POTENTIAL FOR DAMAGING WIND AND POTENTIAL
FOR A FEW TORNADIC TSTMS WITH THIS CONVECTION.
AVIATION...TORNADOES AND 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 26040.
...EDWARDS/CORFIDI
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW3
WW 393 TORNADO IA IL MO LM 301255Z - 301900Z
AXIS..90 STATUTE MILES EAST AND WEST OF LINE..
30SSW UIN/QUINCY IL/ - 25NW MMO/MARSEILLES IL/
..AVIATION COORDS.. 80NM E/W /19SSW UIN - 32W JOT/
HAIL SURFACE AND ALOFT..1.5 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 500. MEAN STORM MOTION VECTOR 26040.
REPLACES WW 392..IA IL MO
LAT...LON 39549309 41619076 41618727 39548973
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU3.
Watch 393 Status Report Messages:
STATUS REPORT #2 ON WW 393
VALID 301555Z - 301640Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 5 ESE IRK TO
40 ENE UIN TO 15 N MMO.
..SPC..05/30/08
ATTN...WFO...DVN...LSX...ILX...LOT...
&&
STATUS REPORT FOR WT 393
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
ILC001-009-017-031-043-063-091-093-099-105-107-113-125-129-179-
197-203-301640-
IL
. ILLINOIS COUNTIES INCLUDED ARE
ADAMS BROWN CASS
COOK DUPAGE GRUNDY
KANKAKEE KENDALL LA SALLE
LIVINGSTON LOGAN MCLEAN
MASON MENARD TAZEWELL
WILL WOODFORD
$$
MOC127-205-301640-
MO
. MISSOURI COUNTIES INCLUDED ARE
MARION SHELBY
$$
LMZ741-742-301640-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
WILMETTE HARBOR TO NORTHERLY ISLAND IL
NORTHERLY ISLAND TO CALUMET HARBOR IL
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #1 ON WW 393
VALID 301425Z - 301540Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 SSW IRK
TO 20 NW UIN TO 30 ESE BRL TO 30 SE MLI TO 30 ENE MLI.
..SPC..05/30/08
ATTN...WFO...DVN...LSX...ILX...LOT...
&&
STATUS REPORT FOR WT 393
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
ILC001-009-011-017-031-043-057-063-091-093-095-099-105-107-109-
113-123-125-129-143-155-169-175-179-197-203-301540-
IL
. ILLINOIS COUNTIES INCLUDED ARE
ADAMS BROWN BUREAU
CASS COOK DUPAGE
FULTON GRUNDY KANKAKEE
KENDALL KNOX LA SALLE
LIVINGSTON LOGAN MCDONOUGH
MCLEAN MARSHALL MASON
MENARD PEORIA PUTNAM
SCHUYLER STARK TAZEWELL
WILL WOODFORD
$$
MOC127-205-301540-
MO
. MISSOURI COUNTIES INCLUDED ARE
MARION SHELBY
$$
LMZ741-742-301540-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
WILMETTE HARBOR TO NORTHERLY ISLAND IL
NORTHERLY ISLAND TO CALUMET HARBOR IL
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
Note:
Click for Complete Product Text.
Tornadoes
Probability of 2 or more tornadoes
|
Mod (40%)
|
Probability of 1 or more strong (F2-F5) tornadoes
|
Mod (30%)
|
Wind
Probability of 10 or more severe wind events
|
Mod (40%)
|
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 (10%)
|
Combined Severe Hail/Wind
Probability of 6 or more combined severe hail/wind events
|
High (80%)
|
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 
@NWSSPC
