Alert archive / Michigan / Tornado Watches in 2005

Tornado Watch 734

August 18, 200527 counties in Michigan

The Storm Prediction Center issued this tornado watch at Aug 18, 2005, 11:55 PM EDT for 27 counties in Michigan. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Aug 18, 2005, 11:55 PM EDT (03:55 UTC)
Expired
Aug 19, 2005, 4:08 AM EDT
In force
4 hr
Issued by
the Storm Prediction Center
All 27 counties

Barry County, MI, Benzie County, MI, Calhoun County, MI, Clare County, MI, Clinton County, MI, Crawford County, MI, Eaton County, MI, Grand Traverse County, MI, Gratiot County, MI, Ingham County, MI, Ionia County, MI, Isabella County, MI, Jackson County, MI, Kalamazoo County, MI, Kalkaska County, MI, Kent County, MI, Lake County, MI, Manistee County, MI, Mecosta County, MI, Midland County, MI, Missaukee County, MI, Montcalm County, MI, Newaygo County, MI, Osceola County, MI, Ottawa County, MI, Roscommon County, MI, Wexford County, MI

The radar

The Grand Rapids radar (KGRR), 90 km from the middle of the area, began a volume at 03:58 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.

Warnings issued inside it

5 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Aug 19, 12:00 AM EDTSevere Thunderstorm WarningGRRLake46 min
Aug 19, 12:34 AM EDTSevere Thunderstorm WarningGRRMecosta29 min
Aug 19, 12:50 AM EDTSevere Thunderstorm WarningGRROsceola43 min
Aug 19, 1:01 AM EDTSevere Thunderstorm WarningGRRClare, Isabella45 min
Aug 19, 1:43 AM EDTSevere Thunderstorm WarningGRROsceola19 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

Detroit, MI (KDTX), launched 00:00Z, 3.9 hours before the alert went out and 206 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.

Skew-T log-pSkew-T log-p diagram, Detroit, MI at 00:00Z on 2005-08-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 142 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Detroit, MI at 00:00Z on 2005-08-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 146 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
142 J/kg
Mixed-layer CIN
-56 J/kg
Mixed-layer LCL
1296 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
146 m²/s²
0-3 km storm-relative helicity
315 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.3

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WWUS20 KWNS 190355
SEL4  
SPC WW 190355
MIZ000-LMZ000-191000-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 734
NWS STORM PREDICTION CENTER NORMAN OK
1055 PM CDT THU AUG 18 2005

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF 

       SOUTHWEST AND CENTRAL LOWER MICHIGAN
       LAKE MICHIGAN

EFFECTIVE THIS THURSDAY NIGHT AND FRIDAY MORNING FROM 1055 PM
UNTIL 500 AM 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 50 STATUTE MILES
EAST AND WEST OF A LINE FROM 5 MILES NORTH NORTHWEST OF TRAVERSE
CITY MICHIGAN TO 30 MILES EAST SOUTHEAST OF KALAMAZOO MICHIGAN. 
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU4).

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...CONTINUE...WW 731...WW 733...

DISCUSSION...STRONG MID/UPPER LEVEL TROUGH WILL SPREAD ENEWD WITH
ACCOMPANYING 45-50 KT WLY MID LEVEL JET OVERSPREADING LOWER MI
TONIGHT.  SURFACE WARM FRONT WILL LIKELY SHIFT N-NEWD THROUGH THE
NIGHT AS LOW CENTER DEVELOPS ACROSS NRN LOWER MI.  ACCOMPANYING
LARGE SCALE ASCENT WILL INCREASE STORMS OVER THE REGION WITH THE
THREAT OF SUPERCELLS. ENHANCED LOW LEVEL SHEAR AND LOW LCLS WITHIN
MOIST WARM SECTOR WILL BECOME FAVORABLE FOR A THREAT OF TORNADOES.

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 26025.


...EVANS

444,0843 420,0840 420,0855 444,0863

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 18, 10:28 PM EDTMesoscale DiscussionSPCAllegan, Barry, Berrien, Branch, Calhoun, Cass and 4 more92 min
Aug 19, 2:08 AM EDTMesoscale DiscussionSPCAlcona, Arenac, Barry, Bay, Benzie, Calhoun and 31 more97 min

Nearby

Tornado Watches in Michigan, 2005Every tornado watch in 2005

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.