Alert archive / Wisconsin / Tornado Watches in 2007
Tornado Watch 679
The Storm Prediction Center issued this tornado watch at Sep 21, 2007, 3:46 PM EDT for 9 counties in Michigan; 31 counties in Wisconsin. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- Sep 21, 2007, 3:46 PM EDT (19:46 UTC)
- Expired
- Sep 21, 2007, 11:37 PM EDT
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 70 kt
All 40 counties
Baraga County, MI, Dickinson County, MI, Gogebic County, MI, Houghton County, MI, Iron County, MI, Keweenaw County, MI, Marquette County, MI, Menominee County, MI, Ontonagon County, MI, Adams County, WI, Ashland County, WI, Bayfield County, WI, Chippewa County, WI, Clark County, WI, Eau Claire County, WI, Florence County, WI, Forest County, WI, Iron County, WI, Jackson County, WI, Juneau County, WI, La Crosse County, WI, Langlade County, WI, Lincoln County, WI, Marathon County, WI, Marinette County, WI, Menominee County, WI, Monroe County, WI, Oconto County, WI, Oneida County, WI, Portage County, WI, Price County, WI, Rusk County, WI, Sawyer County, WI, Shawano County, WI, Taylor County, WI, Trempealeau County, WI, Vilas County, WI, Waupaca County, WI, Waushara County, WI, Wood County, WI
The radar
The Marquette radar (KMQT), 183 km from the middle of the area, began a volume at 19:49 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
- 40%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 80%
- One or more gusts of 65 knots or more
- 50%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 95%
Warnings issued inside it
10 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 21, 4:57 PM EDT | Severe Thunderstorm Warning | ARX | Jackson, La Crosse, Monroe, Trempealeau, Vernon | 78 min |
| Sep 21, 5:04 PM EDT | Severe Thunderstorm Warning | ARX | Clark | 26 min |
| Sep 21, 5:08 PM EDT | Severe Thunderstorm Warning | DLH | Ashland, Bayfield | 52 min |
| Sep 21, 6:06 PM EDT | Severe Thunderstorm Warning | ARX | Adams, Juneau | 39 min |
| Sep 21, 6:16 PM EDT | Severe Thunderstorm Warning | ARX | Monroe | 29 min |
| Sep 21, 6:25 PM EDT | Severe Thunderstorm Warning | MQT | Gogebic, Ontonagon | 50 min |
| Sep 21, 6:30 PM EDT | Severe Thunderstorm Warning | GRB | Vilas | 15 min |
| Sep 21, 6:36 PM EDT | Severe Thunderstorm Warning | MQT | Gogebic, Iron | 24 min |
| Sep 21, 7:03 PM EDT | Severe Thunderstorm Warning | GRB | Waushara | 42 min |
| Sep 21, 7:16 PM EDT | Severe Thunderstorm Warning | MQT | Baraga, Houghton, Ontonagon | 44 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, 7.8 hours before the alert went out and 218 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
- 149 J/kg
- Mixed-layer CIN
- -209 J/kg
- Mixed-layer LCL
- 1031 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 194 m²/s²
- 0-3 km storm-relative helicity
- 167 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.9
The text
As transmitted, in the capitals the NWS used until 2016.
000
WWUS20 KWNS 211949
SEL9
SPC WW 211949
MIZ000-WIZ000-LSZ000-220400-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 679
NWS STORM PREDICTION CENTER NORMAN OK
250 PM CDT FRI SEP 21 2007
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
WESTERN PORTIONS OF UPPER MICHIGAN
LARGE PART OF NORTHERN AND CENTRAL WISCONSIN
LAKE SUPERIOR
EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 250 PM UNTIL
1100 PM CDT.
TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 85 STATUTE
MILES EAST AND WEST OF A LINE FROM 45 MILES WEST NORTHWEST OF
HOUGHTON MICHIGAN TO 35 MILES EAST OF CAMP DOUGLAS WISCONSIN.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU9).
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...VERY STRONG S/WV TROUGH AND ASSOCIATED WIND FIELDS
SUPPORTS RAPID DEVELOPMENT OF SEVERE THUNDERSTORMS ALONG/AHEAD OF
COLD FRONT NOW MOVING INTO WRN WI. WITH STRONG/VEERING SHEAR
PROFILES AND MLCAPES TO 1500 J/KG...SUPERCELLS ARE LIKELY
ALONG/AHEAD OF THE FRONT. STORMS WILL QUICKLY EVOLVE INTO A SQUALL
LINE WITH AN ENHANCED WIND DAMAGE POTENTIAL SPREADING EWD ACROSS THE
WATCH DURING THE EVENING.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
550. MEAN STORM MOTION VECTOR 24040.
...HALESSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 21, 7:04 AM EDT | Severe Thunderstorm Watch | SPC | Gogebic, Keweenaw, Ontonagon | 5 hr |
| Sep 21, 11:24 AM EDT | Mesoscale Discussion | SPC | Menominee | 66 min |
| Sep 21, 2:34 PM EDT | Mesoscale Discussion | SPC | Baraga, Gogebic, Houghton, Iron, Ontonagon | 116 min |
| Sep 21, 7:49 PM EDT | Mesoscale Discussion | SPC | Alger, Delta, Leelanau, Luce, Mackinac, Menominee and 1 more | 86 min |
| Sep 21, 12:09 AM EDT | Mesoscale Discussion | SPC | Barron, Burnett, Chippewa, Clark, Dunn, Eau Claire and 9 more | 81 min |
| Sep 21, 12:13 AM EDT | Severe Thunderstorm Watch | SPC | Ashland, Bayfield, Burnett, Douglas, Iron, Price and 2 more | 7 hr |
| Sep 21, 4:08 AM EDT | Mesoscale Discussion | SPC | Ashland, Bayfield, Burnett, Douglas, Iron, Price and 2 more | 2 hr |
| Sep 21, 4:17 PM EDT | Mesoscale Discussion | SPC | Crawford, Grant, Vernon | 88 min |
| Sep 21, 4:53 PM EDT | Severe Thunderstorm Watch | SPC | Columbia, Crawford, Grant, Green Lake, Iowa, Lafayette and 4 more | 4 hr |
| Sep 21, 7:17 PM EDT | Mesoscale Discussion | SPC | Columbia, Dane, Dodge, Grant, Green, Iowa and 7 more | 88 min |
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.