Alert archive / Michigan / Severe Thunderstorm Watches in 2012
Severe Thunderstorm Watch 229
The Storm Prediction Center issued this severe thunderstorm watch at May 3, 2012, 12:41 PM EDT for 29 counties in Michigan. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- May 3, 2012, 12:41 PM EDT (16:41 UTC)
- Expired
- May 3, 2012, 6:00 PM EDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 29 counties
Alcona County, MI, Alpena County, MI, Antrim County, MI, Arenac County, MI, Bay County, MI, Benzie County, MI, Clare County, MI, Crawford County, MI, Gladwin County, MI, Grand Traverse County, MI, Iosco County, MI, Isabella County, MI, Kalkaska County, MI, Lake County, MI, Leelanau County, MI, Manistee County, MI, Mason County, MI, Mecosta County, MI, Midland County, MI, Missaukee County, MI, Montmorency County, MI, Newaygo County, MI, Oceana County, MI, Ogemaw County, MI, Osceola County, MI, Oscoda County, MI, Otsego County, MI, Roscommon County, MI, Wexford County, MI
The radar
The NCL Michigan radar (KAPX), 59 km from the middle of the area, began a volume at 16:43 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 40%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
15 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 3, 12:50 PM EDT | Flash Flood Warning | GRR | Lake | 6 hr |
| May 3, 1:09 PM EDT | Severe Thunderstorm Warning | GRR | Mason | 41 min |
| May 3, 1:23 PM EDT | Severe Thunderstorm Warning | GRR | Lake | 52 min |
| May 3, 2:03 PM EDT | Severe Thunderstorm Warning | GRR | Osceola | 57 min |
| May 3, 2:57 PM EDT | Severe Thunderstorm Warning | GRR | Oceana | 63 min |
| May 3, 3:01 PM EDT | Flash Flood Warning | GRR | Osceola | 5 hr |
| May 3, 3:02 PM EDT | Severe Thunderstorm Warning | GRR | Newaygo | 43 min |
| May 3, 3:21 PM EDT | Severe Thunderstorm Warning | GRR | Clare | 54 min |
| May 3, 3:36 PM EDT | Severe Thunderstorm Warning | GRR | Mecosta | 54 min |
| May 3, 3:56 PM EDT | Tornado Warning | APX | Arenac, Gladwin | 49 min |
| May 3, 4:16 PM EDT | Tornado Warning | APX | Gladwin | 32 min |
| May 3, 4:16 PM EDT | Severe Thunderstorm Warning | GRR | Isabella | 38 min |
| May 3, 4:17 PM EDT | Severe Thunderstorm Warning | DTX | Bay, Midland | 58 min |
| May 3, 5:10 PM EDT | Severe Thunderstorm Warning | DTX | Bay, Saginaw, Tuscola | 50 min |
| May 3, 5:13 PM EDT | Severe Thunderstorm Warning | GRR | Kent, Newaygo, Ottawa | 41 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Green Bay/Straub, WI (KGRB), launched 12:00Z, 4.7 hours before the alert went out and 225 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 321 J/kg
- Mixed-layer CIN
- -146 J/kg
- Mixed-layer LCL
- 565 m above ground
- 0-6 km bulk shear
- 58 kt
- 0-1 km storm-relative helicity
- 160 m²/s²
- 0-3 km storm-relative helicity
- 220 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.8
The text
As transmitted, in the capitals the NWS used until 2016.
969
WWUS20 KWNS 031642
SEL9
SPC WW 031642
MIZ000-LHZ000-LMZ000-032200-
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 229
NWS STORM PREDICTION CENTER NORMAN OK
1245 PM EDT THU MAY 3 2012
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
NORTHERN LOWER MICHIGAN
LAKE HURON
LAKE MICHIGAN
EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 1245 PM UNTIL
600 PM EDT.
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 10 MILES NORTHWEST
OF MANISTEE MICHIGAN TO 50 MILES SOUTH OF ALPENA MICHIGAN. FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU9).
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...STORMS INCREASING NORTH OF A WARM FRONT ACROSS LOWER MI
WITH A BOWING LINE SEGMENT MOVING AT ABOUT 50KT ACROSS NRN LAKE MI.
DOWNSTREAM AIRMASS IS WARMING SUFFICIENTLY TO SUPPORT SOME THREAT
FOR DAMAGING WINDS AND PERHAPS SEVERE HAIL AS THE STORMS SPREAD
ACROSS THE NRN PORTION OF LOWER MI NEXT FEW HOURS.
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 25040.
...CARBINSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 3, 12:51 AM EDT | Mesoscale Discussion | SPC | Manistee, Mason, Oceana | 54 min |
| May 3, 11:34 AM EDT | Mesoscale Discussion | SPC | Arenac, Bay, Clare, Clinton, Genesee, Gladwin and 28 more | 86 min |
| May 3, 2:35 PM EDT | Severe Thunderstorm Watch | SPC | Allegan, Barry, Berrien, Branch, Calhoun, Cass and 27 more | 8 hr |
| May 3, 2:39 PM EDT | Mesoscale Discussion | SPC | Antrim, Arenac, Bay, Benzie, Clare, Crawford and 18 more | 66 min |
| May 3, 3:53 PM EDT | Mesoscale Discussion | SPC | Berrien | 67 min |
| May 3, 4:33 PM EDT | Mesoscale Discussion | SPC | Allegan, Barry, Bay, Calhoun, Cass, Clinton and 15 more | 57 min |
| May 3, 6:57 PM EDT | Mesoscale Discussion | SPC | Allegan, Barry, Berrien, Branch, Calhoun, Cass and 28 more | 63 min |
Nearby
Severe Thunderstorm Watches in Michigan, 2012Every severe thunderstorm watch in 2012
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.