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The expiration time in the watch graphic is amended if the watch is
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Watch Status Reports.
SEL1
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 181
NWS STORM PREDICTION CENTER NORMAN OK
1045 AM EDT SAT APR 25 2009
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
MUCH OF LOWER MICHIGAN
LAKE HURON
EFFECTIVE THIS SATURDAY MORNING AND AFTERNOON FROM 1045 AM UNTIL
400 PM EDT.
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 80
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 35 MILES NORTHWEST
OF GRAND RAPIDS MICHIGAN TO 40 MILES EAST OF BAD AXE MICHIGAN.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU1).
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...LINES OF THUNDERSTORMS INCREASING AND MOVING RAPIDLY
EWD ACROSS LWR MI WHERE AIRMASS HAS DESTABILIZED UNDER STRONG
MORNING HEATING. WITH 40-50KT OF SHEAR DAMAGING WINDS WILL BE THE
PRIMARY THREAT AS STRONG WIND MAX PASSES JUST TO THE NORTH OF AREA.
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 25035.
...HALES
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW1
WW 181 SEVERE TSTM MI LH 251445Z - 252000Z
AXIS..80 STATUTE MILES NORTH AND SOUTH OF LINE..
35NW GRR/GRAND RAPIDS MI/ - 40E BAX/BAD AXE MI/
..AVIATION COORDS.. 70NM N/S /4NNE MKG - 39NE ECK/
HAIL SURFACE AND ALOFT..2 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 450. MEAN STORM MOTION VECTOR 25035.
LAT...LON 44388601 44938219 42618219 42088601
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU1.
Watch 181 Status Report Messages:
STATUS REPORT #4 ON WW 181
VALID 251900Z - 252040Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 10 E MKG TO
20 ESE RQB TO 50 NE BAX.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 564
..SPC..04/25/09
ATTN...WFO...APX...GRR...DTX...
&&
STATUS REPORT FOR WS 181
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MIC005-015-017-025-037-045-049-057-063-065-067-073-075-077-081-
087-093-099-111-117-125-139-145-147-151-155-157-159-161-163-
252040-
MI
. MICHIGAN COUNTIES INCLUDED ARE
ALLEGAN BARRY BAY
CALHOUN CLINTON EATON
GENESEE GRATIOT HURON
INGHAM IONIA ISABELLA
JACKSON KALAMAZOO KENT
LAPEER LIVINGSTON MACOMB
MIDLAND MONTCALM OAKLAND
OTTAWA SAGINAW ST. CLAIR
SANILAC SHIAWASSEE TUSCOLA
VAN BUREN WASHTENAW WAYNE
$$
LCZ422-423-460-LHZ422-441-442-443-462-463-464-252040-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
ST. CLAIR RIVER
DETROIT RIVER
LAKE ST. CLAIR OPEN LAKE (U.S. PORTION)
INNER SAGINAW BAY SW OF POINT AU GRES TO BAY PORT MI
PORT AUSTIN TO HARBOR BEACH MI
HARBOR BEACH TO PORT SANILAC MI
PORT SANILAC TO PORT HURON MI
LAKE HURON FROM PORT AUSTIN TO HARBOR BEACH 5NM OFF SHORE TO THE
US/CANADIAN BORDER
LAKE HURON FROM HARBOR BEACH TO PORT SANILAC 5NM OFF SHORE TO
US/CANADIAN BORDER
LAKE HURON FROM PORT SANILAC TO PORT HURON 5NM OFF SHORE TO
US/CANADIAN BORDER
$$
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.
$$
STATUS REPORT #3 ON WW 181
VALID 251755Z - 251840Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 NE MKG TO
25 SSW HTL TO 25 WNW OSC TO 65 ENE OSC.
..SPC..04/25/09
ATTN...WFO...APX...GRR...DTX...
&&
STATUS REPORT FOR WS 181
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MIC005-011-015-017-025-035-037-045-049-051-057-063-065-067-069-
073-075-077-081-087-093-099-107-111-117-125-129-139-145-147-151-
155-157-159-161-163-251840-
MI
. MICHIGAN COUNTIES INCLUDED ARE
ALLEGAN ARENAC BARRY
BAY CALHOUN CLARE
CLINTON EATON GENESEE
GLADWIN GRATIOT HURON
INGHAM IONIA IOSCO
ISABELLA JACKSON KALAMAZOO
KENT LAPEER LIVINGSTON
MACOMB MECOSTA MIDLAND
MONTCALM OAKLAND OGEMAW
OTTAWA SAGINAW ST. CLAIR
SANILAC SHIAWASSEE TUSCOLA
VAN BUREN WASHTENAW WAYNE
$$
LCZ422-423-460-LHZ349-363-421-422-441-442-443-462-463-464-
251840-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
ST. CLAIR RIVER
DETROIT RIVER
LAKE ST. CLAIR OPEN LAKE (U.S. PORTION)
STURGEON POINT TO ALABASTER MI
LAKE HURON FROM STURGEON POINT TO ALABASTER MI 5NM OFF SHORE TO
US/CANADIAN BORDER
OUTER SAGINAW BAY SW OF ALABASTER TO PORT AUSTIN MI TO INNER
SAGINAW BAY
INNER SAGINAW BAY SW OF POINT AU GRES TO BAY PORT MI
PORT AUSTIN TO HARBOR BEACH MI
HARBOR BEACH TO PORT SANILAC MI
PORT SANILAC TO PORT HURON MI
LAKE HURON FROM PORT AUSTIN TO HARBOR BEACH 5NM OFF SHORE TO THE
US/CANADIAN BORDER
LAKE HURON FROM HARBOR BEACH TO PORT SANILAC 5NM OFF SHORE TO
US/CANADIAN BORDER
LAKE HURON FROM PORT SANILAC TO PORT HURON 5NM OFF SHORE TO
US/CANADIAN BORDER
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #2 ON WW 181
VALID 251700Z - 251840Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 NE MKG TO
20 ENE RQB TO 20 SSW HTL TO 15 NNE HTL.
..SPC..04/25/09
ATTN...WFO...APX...GRR...DTX...
&&
STATUS REPORT FOR WS 181
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MIC001-005-011-015-017-025-035-037-045-049-051-057-063-065-067-
069-073-075-077-081-087-093-099-107-111-117-125-129-139-143-145-
147-151-155-157-159-161-163-251840-
MI
. MICHIGAN COUNTIES INCLUDED ARE
ALCONA ALLEGAN ARENAC
BARRY BAY CALHOUN
CLARE CLINTON EATON
GENESEE GLADWIN GRATIOT
HURON INGHAM IONIA
IOSCO ISABELLA JACKSON
KALAMAZOO KENT LAPEER
LIVINGSTON MACOMB MECOSTA
MIDLAND MONTCALM OAKLAND
OGEMAW OTTAWA ROSCOMMON
SAGINAW ST. CLAIR SANILAC
SHIAWASSEE TUSCOLA VAN BUREN
WASHTENAW WAYNE
$$
LCZ422-423-460-LHZ348-349-362-363-421-422-441-442-443-462-463-464-
251840-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
ST. CLAIR RIVER
DETROIT RIVER
LAKE ST. CLAIR OPEN LAKE (U.S. PORTION)
PRESQUE ISLE LIGHT TO STURGEON PT MI INCLUDING THUNDER BAY
NATIONAL MARINE SANCTUARY
STURGEON POINT TO ALABASTER MI
LAKE HURON FROM PRESQUE ISLE LIGHT TO STURGEON POINT MI 5NM OFF
SHORE TO US/CANADIAN BORDER
LAKE HURON FROM STURGEON POINT TO ALABASTER MI 5NM OFF SHORE TO
US/CANADIAN BORDER
OUTER SAGINAW BAY SW OF ALABASTER TO PORT AUSTIN MI TO INNER
SAGINAW BAY
INNER SAGINAW BAY SW OF POINT AU GRES TO BAY PORT MI
PORT AUSTIN TO HARBOR BEACH MI
HARBOR BEACH TO PORT SANILAC MI
PORT SANILAC TO PORT HURON MI
LAKE HURON FROM PORT AUSTIN TO HARBOR BEACH 5NM OFF SHORE TO THE
US/CANADIAN BORDER
LAKE HURON FROM HARBOR BEACH TO PORT SANILAC 5NM OFF SHORE TO
US/CANADIAN BORDER
LAKE HURON FROM PORT SANILAC TO PORT HURON 5NM OFF SHORE TO
US/CANADIAN BORDER
$$
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.
$$
STATUS REPORT #1 ON WW 181
VALID 251600Z - 251740Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 ENE MBL
TO 25 NW OSC TO 50 ENE APN.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 559
..SPC..04/25/09
ATTN...WFO...APX...GRR...DTX...
&&
STATUS REPORT FOR WS 181
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MIC001-005-011-015-017-025-035-037-045-049-051-057-063-065-067-
069-073-075-077-081-087-093-099-107-111-117-123-125-129-133-139-
143-145-147-151-155-157-159-161-163-251740-
MI
. MICHIGAN COUNTIES INCLUDED ARE
ALCONA ALLEGAN ARENAC
BARRY BAY CALHOUN
CLARE CLINTON EATON
GENESEE GLADWIN GRATIOT
HURON INGHAM IONIA
IOSCO ISABELLA JACKSON
KALAMAZOO KENT LAPEER
LIVINGSTON MACOMB MECOSTA
MIDLAND MONTCALM NEWAYGO
OAKLAND OGEMAW OSCEOLA
OTTAWA ROSCOMMON SAGINAW
ST. CLAIR SANILAC SHIAWASSEE
TUSCOLA VAN BUREN WASHTENAW
WAYNE
$$
LCZ422-423-460-LHZ348-349-362-363-421-422-441-442-443-462-463-464-
251740-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
ST. CLAIR RIVER
DETROIT RIVER
LAKE ST. CLAIR OPEN LAKE (U.S. PORTION)
PRESQUE ISLE LIGHT TO STURGEON PT MI INCLUDING THUNDER BAY
NATIONAL MARINE SANCTUARY
STURGEON POINT TO ALABASTER MI
LAKE HURON FROM PRESQUE ISLE LIGHT TO STURGEON POINT MI 5NM OFF
SHORE TO US/CANADIAN BORDER
LAKE HURON FROM STURGEON POINT TO ALABASTER MI 5NM OFF SHORE TO
US/CANADIAN BORDER
OUTER SAGINAW BAY SW OF ALABASTER TO PORT AUSTIN MI TO INNER
SAGINAW BAY
INNER SAGINAW BAY SW OF POINT AU GRES TO BAY PORT MI
PORT AUSTIN TO HARBOR BEACH MI
HARBOR BEACH TO PORT SANILAC MI
PORT SANILAC TO PORT HURON MI
LAKE HURON FROM PORT AUSTIN TO HARBOR BEACH 5NM OFF SHORE TO THE
US/CANADIAN BORDER
LAKE HURON FROM HARBOR BEACH TO PORT SANILAC 5NM OFF SHORE TO
US/CANADIAN BORDER
LAKE HURON FROM PORT SANILAC TO PORT HURON 5NM OFF SHORE TO
US/CANADIAN BORDER
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
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 (50%)
|
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.
weather.gov 
