Alert archive / Michigan / Severe Thunderstorm Watches in 2002
Severe Thunderstorm Watch 620
The Storm Prediction Center issued this severe thunderstorm watch at Aug 17, 2002, 10:10 AM EDT for 30 counties in Michigan. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 17, 2002, 10:10 AM EDT (14:10 UTC)
- Expired
- Aug 17, 2002, 4:00 PM EDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
All 30 counties
Alcona County, MI, Alpena County, MI, Antrim County, MI, Arenac County, MI, Bay County, MI, Benzie County, MI, Cheboygan 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, Mecosta County, MI, Midland County, MI, Missaukee County, MI, Montcalm County, MI, Montmorency County, MI, Newaygo County, MI, Ogemaw County, MI, Osceola County, MI, Oscoda County, MI, Otsego County, MI, Presque Isle County, MI, Roscommon County, MI, Wexford County, MI
The radar
The NCL Michigan radar (KAPX), 40 km from the middle of the area, began a volume at 14:13 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.
The nearest sounding before it
Alpena, MI (KAPX), launched 12:00Z, 2.2 hours before the alert went out and 210 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1705 m above ground
- 0-6 km bulk shear
- 43 kt
- 0-1 km storm-relative helicity
- 175 m²/s²
- 0-3 km storm-relative helicity
- 213 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 WWUS20 KWNS 171411 SEL0 SPC WW 171410 MIZ000-LMZ000-LHZ000-172000- URGENT - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WATCH NUMBER 620 STORM PREDICTION CENTER NORMAN OK 1010 AM EDT SAT AUG 17 2002 THE STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR PORTIONS OF LOWER MICHIGAN LAKE MICHIGAN LAKE HURON EFFECTIVE THIS SATURDAY MORNING AND AFTERNOON FROM 1010 AM UNTIL 400 PM EDT. HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS. THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 75 STATUTE MILES NORTH AND SOUTH OF A LINE FROM 10 MILES SOUTH SOUTHWEST OF MANISTEE MICHIGAN TO 30 MILES NORTHEAST OF OSCODA MICHIGAN. 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...PRE-FRONTAL SQUALL LINE OVER LM WILL MOVE RAPIDLY EWD AS WARM FRONT MOVES NWD THRU LWR MI. WITH INCRESINGLY MOIST/UNSTABLE AIRMASS AHEAD OF LINE...STORMS ALONG LINE EXPECTED TO INTENSIFY WITH PRIMARY THREAT BEING DAMAGING WINDS. STRONG MID/UPPER LEVEL WINDS WILL ENHANCE WIND DAMAGE POTENTIAL. AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO 1 INCH EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION VECTOR 25040. ...HALES 451,0861 455,0825 434,0825 430,0861
Nearby
Severe Thunderstorm Watches in Michigan, 2002Every severe thunderstorm watch in 2002
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.