Note:
The expiration time in the watch graphic is amended if the watch is
replaced, cancelled or extended.
Note: Click for
Watch Status Reports.
SEL8
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 328
NWS STORM PREDICTION CENTER NORMAN OK
330 PM EDT SUN MAY 22 2011
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
SOUTHEAST LOWER MICHIGAN
LAKE ERIE
LAKE HURON
EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 330 PM UNTIL 800
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 50
STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES NORTHEAST OF
SAGINAW MICHIGAN TO 30 MILES SOUTH SOUTHEAST OF ANN ARBOR
MICHIGAN. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8).
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 322...WW 323...WW
324...WW 325...WW 326...WW 327...
DISCUSSION...ISOLATED SEVERE STORMS WILL BE POSSIBLE ACROSS THE WW
AREA THIS AFTERNOON INTO EVENING OWING TO THE PRESENCE OF A MOIST
AND MODERATELY UNSTABLE AIR MASS WITH MLCAPE VALUES OF 2000 J/KG.
WHEN COUPLED WITH 35-40 KT OF DEEP-LAYER SHEAR...SETUP WILL FAVOR
THE DEVELOPMENT OF SUPERCELLS CAPABLE OF LARGE HAIL AND LOCALLY
DAMAGING WIND GUSTS.
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 500. MEAN STORM
MOTION VECTOR 25025.
...MEAD
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW8
WW 328 SEVERE TSTM MI LE LH 221930Z - 230000Z
AXIS..50 STATUTE MILES EAST AND WEST OF LINE..
30NE MBS/SAGINAW MI/ - 30SSE ARB/ANN ARBOR MI/
..AVIATION COORDS.. 45NM E/W /26NE MBS - 25SSW DXO/
HAIL SURFACE AND ALOFT..2 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 500. MEAN STORM MOTION VECTOR 25025.
LAT...LON 43838265 41818255 41818450 43838466
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU8.
Watch 328 Status Report Messages:
STATUS REPORT #2 ON WW 328
VALID 222130Z - 222240Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..COHEN..05/22/11
ATTN...WFO...DTX...
&&
STATUS REPORT FOR WS 328
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MIC017-049-063-087-091-093-099-111-115-125-145-147-151-155-157-
161-163-222240-
MI
. MICHIGAN COUNTIES INCLUDED ARE
BAY GENESEE HURON
LAPEER LENAWEE LIVINGSTON
MACOMB MIDLAND MONROE
OAKLAND SAGINAW ST. CLAIR
SANILAC SHIAWASSEE TUSCOLA
WASHTENAW WAYNE
$$
LCZ422-423-460-LEZ444-LHZ421-422-441-442-443-462-463-464-
222240-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
ST. CLAIR RIVER
DETROIT RIVER
LAKE ST. CLAIR OPEN LAKE (U.S. PORTION)
MICHIGAN WATERS OF LAKE ERIE FROM DETROIT RIVER TO NORTH CAPE MI
OUTER SAGINAW BAY SW OF ALABASTER TO PORT AUSTIN MI TO INNER
SAGINAW BAY
INNER SAGINAW BAY SW OF POINT AU GRES TO BAY PORT MI
PORT AUSTIN TO HARBOR BEACH MI
HARBOR BEACH TO PORT SANILAC MI
PORT SANILAC TO PORT HURON MI
LAKE HURON FROM PORT AUSTIN TO HARBOR BEACH 5NM OFF SHORE TO THE
US/CANADIAN BORDER
LAKE HURON FROM HARBOR BEACH TO PORT SANILAC 5NM OFF SHORE TO
US/CANADIAN BORDER
LAKE HURON FROM PORT SANILAC TO PORT HURON 5NM OFF SHORE TO
US/CANADIAN BORDER
$$
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.
$$
STATUS REPORT #1 ON WW 328
VALID 222100Z - 222240Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..HART..05/22/11
ATTN...WFO...DTX...
&&
STATUS REPORT FOR WS 328
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MIC017-049-063-087-091-093-099-111-115-125-145-147-151-155-157-
161-163-222240-
MI
. MICHIGAN COUNTIES INCLUDED ARE
BAY GENESEE HURON
LAPEER LENAWEE LIVINGSTON
MACOMB MIDLAND MONROE
OAKLAND SAGINAW ST. CLAIR
SANILAC SHIAWASSEE TUSCOLA
WASHTENAW WAYNE
$$
LCZ422-423-460-LEZ444-LHZ421-422-441-442-443-462-463-464-
222240-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
ST. CLAIR RIVER
DETROIT RIVER
LAKE ST. CLAIR OPEN LAKE (U.S. PORTION)
MICHIGAN WATERS OF LAKE ERIE FROM DETROIT RIVER TO NORTH CAPE MI
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 (20%)
|
Probability of 1 or more strong (F2-F5) tornadoes
|
Low (5%)
|
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.