Alert archive / Wisconsin / Tornado Watches in 2007

Tornado Watch 504

July 10, 200712 counties in Michigan; 22 counties in Wisconsin

The Storm Prediction Center issued this tornado watch at Jul 10, 2007, 12:55 PM EDT for 12 counties in Michigan; 22 counties in Wisconsin. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Jul 10, 2007, 12:55 PM EDT (16:55 UTC)
Expired
Jul 10, 2007, 5:39 PM EDT
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt
All 34 counties

Alger County, MI, Baraga County, MI, Delta County, MI, Dickinson County, MI, Gogebic County, MI, Houghton County, MI, Iron County, MI, Luce County, MI, Marquette County, MI, Menominee County, MI, Ontonagon County, MI, Schoolcraft County, MI, Brown County, WI, Calumet County, WI, Door County, WI, Florence County, WI, Forest County, WI, Kewaunee County, WI, Langlade County, WI, Lincoln County, WI, Manitowoc County, WI, Marathon County, WI, Marinette County, WI, Menominee County, WI, Oconto County, WI, Oneida County, WI, Outagamie County, WI, Portage County, WI, Shawano County, WI, Vilas County, WI, Waupaca County, WI, Waushara County, WI, Winnebago County, WI, Wood County, WI

The radar

The Marquette radar (KMQT), 77 km from the middle of the area, began a volume at 16:55 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
50%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
50%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
40%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jul 10, 2:55 PM EDTSevere Thunderstorm WarningGRBMenominee, Shawano35 min
Jul 10, 2:57 PM EDTSevere Thunderstorm WarningMQTDickinson33 min
Jul 10, 3:33 PM EDTSevere Thunderstorm WarningMQTMarquette42 min
Jul 10, 3:59 PM EDTSevere Thunderstorm WarningMQTAlger61 min
Jul 10, 4:03 PM EDTSevere Thunderstorm WarningGRBDoor42 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, 4.9 hours before the alert went out and 161 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, Green Bay/Straub, WI at 12:00Z on 2007-07-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 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, Green Bay/Straub, WI at 12:00Z on 2007-07-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 74 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1010 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
74 m²/s²
0-3 km storm-relative helicity
127 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000
WWUS20 KWNS 101655
SEL4  
SPC WW 101655
MIZ000-WIZ000-LMZ000-LSZ000-110100-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 504
NWS STORM PREDICTION CENTER NORMAN OK
1155 AM CDT TUE JUL 10 2007

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

       THE UPPER PENINSULA OF MICHIGAN
       NORTHEAST WISCONSIN
       LAKE MICHIGAN
       LAKE SUPERIOR

EFFECTIVE THIS TUESDAY MORNING AND EVENING FROM 1155 AM UNTIL 800
PM 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 70 STATUTE
MILES EAST AND WEST OF A LINE FROM 40 MILES NORTH NORTHEAST OF
MARQUETTE MICHIGAN TO 25 MILES SOUTHWEST OF GREEN BAY WISCONSIN. 
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.

DISCUSSION...SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP EARLY THIS
AFTERNOON ALONG A PRE-FRONTAL TROUGH MOVING EWD ACROSS WI/UPPER MI. 
MODERATE INSTABILITY IN THE WARM SECTOR...IN COMBINATION WITH STRONG
DEEP LAYER VERTICAL SHEAR...SHOULD SUPPORT A FEW DISCRETE SUPERCELLS
WITH THE INITIAL DEVELOPMENT.  RELATIVELY RICH LOW-LEVEL MOISTURE
AND STRONGER LOW-LEVEL SHEAR OVER EXTREME NE WI AND UPPER MI MAY
SUPPORT A FEW TORNADOES WITH THE SUPERCELLS.  THE THREAT FOR
DAMAGING WINDS SHOULD ALSO INCREASE AS STORM COVERAGE INCREASES
THROUGH THE AFTERNOON...AND STORM INTERACTIONS LEAD TO MORE LINE
SEGMENT DEVELOPMENT.

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 25035.


...THOMPSON

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 10, 11:29 AM EDTMesoscale DiscussionSPCAlger, Baraga, Delta, Dickinson, Gogebic, Iron and 3 more91 min
Jul 10, 1:55 PM EDTMesoscale DiscussionSPCAntrim, Charlevoix, Cheboygan, Clare, Crawford, Emmet and 20 more95 min
Jul 10, 3:29 PM EDTMesoscale DiscussionSPCAlger, Delta, Menominee, Schoolcraft91 min
Jul 10, 3:54 PM EDTSevere Thunderstorm WatchSPCAlcona, Allegan, Alpena, Antrim, Arenac, Bay and 45 more7 hr
Jul 10, 2:14 PM EDTMesoscale DiscussionSPCGreen, Jefferson, Kenosha, Milwaukee, Ozaukee, Racine and 4 more61 min
Jul 10, 2:43 PM EDTSevere Thunderstorm WatchSPCColumbia, Dane, Dodge, Fond du Lac, Green, Green Lake and 14 more5 hr

Nearby

Tornado Watches in Wisconsin, 2007Tornado Watches in Michigan, 2007Every tornado watch in 2007

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.