Alert archive / Wisconsin / Tornado Watches in 2004
Tornado Watch 87
The Storm Prediction Center issued this tornado watch at Apr 18, 2004, 6:35 PM CDT for Iron County, Michigan; 13 counties in Minnesota; 17 counties in Wisconsin. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 18, 2004, 6:35 PM CDT (23:35 UTC)
- Expired
- Apr 19, 2004, 12:00 AM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
All 31 counties
Iron County, MI, Brown County, MN, Carver County, MN, Dakota County, MN, Goodhue County, MN, Hennepin County, MN, Le Sueur County, MN, Nicollet County, MN, Ramsey County, MN, Rice County, MN, Scott County, MN, Sibley County, MN, Wabasha County, MN, Washington County, MN, Barron County, WI, Buffalo County, WI, Chippewa County, WI, Dunn County, WI, Eau Claire County, WI, Iron County, WI, Oneida County, WI, Pepin County, WI, Pierce County, WI, Polk County, WI, Price County, WI, Rusk County, WI, Saint Croix County, WI, Sawyer County, WI, Taylor County, WI, Vilas County, WI, Washburn County, WI
The radar
The Minneapolis radar (KMPX), 114 km from the middle of the area, began a volume at 23:38 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
19 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 18, 6:42 PM CDT | Severe Thunderstorm Warning | MPX | Anoka, Hennepin | 48 min |
| Apr 18, 6:45 PM CDT | Tornado Warning | MPX | Brown | 45 min |
| Apr 18, 6:50 PM CDT | Severe Thunderstorm Warning | MPX | Carver, McLeod | 40 min |
| Apr 18, 7:02 PM CDT | Severe Thunderstorm Warning | MPX | Nicollet | 58 min |
| Apr 18, 7:02 PM CDT | Severe Thunderstorm Warning | MPX | Barron, Polk | 43 min |
| Apr 18, 7:05 PM CDT | Severe Thunderstorm Warning | DLH | Iron | 40 min |
| Apr 18, 7:12 PM CDT | Severe Thunderstorm Warning | MPX | Dakota, Scott | 63 min |
| Apr 18, 7:13 PM CDT | Severe Thunderstorm Warning | MPX | Ramsey, Washington | 47 min |
| Apr 18, 7:19 PM CDT | Severe Thunderstorm Warning | MPX | Sibley | 41 min |
| Apr 18, 7:20 PM CDT | Severe Thunderstorm Warning | GRB | Vilas | 55 min |
| Apr 18, 7:33 PM CDT | Severe Thunderstorm Warning | MPX | Carver | 42 min |
| Apr 18, 7:43 PM CDT | Severe Thunderstorm Warning | MPX | Barron, Polk, Rusk | 47 min |
| Apr 18, 7:45 PM CDT | Severe Thunderstorm Warning | MPX | Le Sueur, Rice | 60 min |
| Apr 18, 7:54 PM CDT | Tornado Warning | MPX | Scott | 36 min |
| Apr 18, 8:04 PM CDT | Tornado Warning | MPX | Dakota | 26 min |
| Apr 18, 8:14 PM CDT | Severe Thunderstorm Warning | MQT | Iron | 61 min |
| Apr 18, 8:15 PM CDT | Tornado Warning | GRB | Vilas | 30 min |
| Apr 18, 9:00 PM CDT | Severe Thunderstorm Warning | MPX | Chippewa, Dunn, Eau Claire | 60 min |
| Apr 18, 9:11 PM CDT | Severe Thunderstorm Warning | ARX | Wabasha | 64 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
Minneapolis, MN (KMPX), launched 12:00Z, 11.6 hours before the alert went out and 117 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
- 680 J/kg
- Mixed-layer CIN
- -274 J/kg
- Mixed-layer LCL
- 697 m above ground
- 0-6 km bulk shear
- 61 kt
- 0-1 km storm-relative helicity
- 361 m²/s²
- 0-3 km storm-relative helicity
- 401 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 4.3
The text
As transmitted, in the capitals the NWS used until 2016.
000
WWUS20 KWNS 182334
SEL7
SPC WW 182335
MIZ000-MNZ000-WIZ000-190500-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 87
NWS STORM PREDICTION CENTER NORMAN OK
635 PM CDT SUN APR 18 2004
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
WESTERN UPPER MICHIGAN
SOUTHEASTERN MINNESOTA
WESTERN AND NORTHERN WISCONSIN
EFFECTIVE THIS SUNDAY NIGHT FROM 635 PM UNTIL MIDNIGHT CDT.
...THIS IS A PARTICULARLY DANGEROUS SITUATION...
DESTRUCTIVE TORNADOES...LARGE HAIL TO 3 INCHES IN DIAMETER...
THUNDERSTORM WIND GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE
POSSIBLE IN THESE AREAS.
THE TORNADO WATCH AREA IS ALONG AND 80 STATUTE MILES EAST AND WEST
OF A LINE FROM 25 MILES EAST OF MANKATO MINNESOTA TO 55 MILES
NORTH OF RHINELANDER WISCONSIN.
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...THIS TORNADO WATCH REPLACES TORNADO
WATCH NUMBER 82. WATCH NUMBER 82 WILL NOT BE IN EFFECT AFTER 635
PM CDT. CONTINUE...WW 83...WW 85...WW 86...
DISCUSSION...TORNADIC SUPERCELLS HAVE DEVELOPED ALONG BAND OF SEVERE
THUNDERSTORMS FROM NWRN WI SWWD INTO SWRN MN. WITH VERY STRONG
SHEAR PROFILES IN PLACE AND APPROACH OF VIGOROUS TROUGH FROM THE
SW...CONDITIONS WILL REMAIN FAVORABLE THROUGH THE EVENING FOR
POTENTIAL LARGE TORNADOES AND VERY DAMAGING WINDS AS THE SEVERE
CONVECTIVE SYSTEM CONTINUES E.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550.
MEAN STORM MOTION VECTOR 24045.
...HALES
441,0950 462,0910 462,0874 441,0914SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 18, 1:49 AM CDT | Mesoscale Discussion | SPC | Benzie, Grand Traverse, Manistee, Mason, Wexford | 56 min |
| Apr 18, 8:04 AM CDT | Mesoscale Discussion | SPC | Gogebic, Iron, Ontonagon | 86 min |
| Apr 18, 11:26 AM CDT | Mesoscale Discussion | SPC | Alger, Dickinson, Marquette, Schoolcraft | 3 hr |
| Apr 17, 7:45 PM CDT | Severe Thunderstorm Watch | SPC | Blue Earth, Dodge, Faribault, Fillmore, Freeborn, Houston and 7 more | 5 hr |
| Apr 17, 9:31 PM CDT | Mesoscale Discussion | SPC | Blue Earth, Dodge, Faribault, Fillmore, Freeborn, Houston and 7 more | 119 min |
| Apr 17, 10:05 PM CDT | Tornado Watch | SPC | Blue Earth, Dodge, Faribault, Fillmore, Freeborn, Houston and 7 more | 5 hr |
| Apr 17, 11:10 PM CDT | Mesoscale Discussion | SPC | Big Stone, Chippewa, Cottonwood, Grant, Jackson, Kandiyohi and 14 more | 95 min |
| Apr 17, 11:35 PM CDT | Severe Thunderstorm Watch | SPC | Big Stone, Brown, Chippewa, Cottonwood, Jackson, Kandiyohi and 16 more | 5 hr |
| Apr 17, 11:50 PM CDT | Mesoscale Discussion | SPC | Blue Earth, Dodge, Faribault, Fillmore, Freeborn, Houston and 7 more | 85 min |
| Apr 18, 12:30 AM CDT | Severe Thunderstorm Watch | SPC | Anoka, Carver, Chisago, Dakota, Goodhue, Hennepin and 11 more | 5 hr |
| Apr 18, 2:37 AM CDT | Mesoscale Discussion | SPC | Aitkin, Anoka, Benton, Big Stone, Brown, Carlton and 40 more | 53 min |
| Apr 18, 4:43 AM CDT | Mesoscale Discussion | SPC | Aitkin, Benton, Carlton, Cass, Chisago, Crow Wing and 15 more | 32 min |
| Apr 18, 12:39 PM CDT | Mesoscale Discussion | SPC | Aitkin, Anoka, Benton, Big Stone, Carlton, Carver and 32 more | 2 hr |
| Apr 18, 1:40 PM CDT | Tornado Watch | SPC | Aitkin, Anoka, Benton, Carlton, Carver, Chippewa and 32 more | 6 hr |
| Apr 18, 2:20 PM CDT | Severe Thunderstorm Watch | SPC | Lincoln, Lyon, Pipestone, Rock | 6 hr |
| Apr 18, 3:33 PM CDT | Mesoscale Discussion | SPC | Aitkin, Anoka, Benton, Carlton, Chisago, Crow Wing and 12 more | 117 min |
| Apr 18, 4:15 PM CDT | Mesoscale Discussion | SPC | Blue Earth, Brown, Cottonwood, Dodge, Faribault, Fillmore and 15 more | 60 min |
| Apr 18, 4:40 PM CDT | Tornado Watch | SPC | Blue Earth, Cottonwood, Dodge, Faribault, Freeborn, Jackson and 6 more | 5 hr |
| Apr 18, 5:23 PM CDT | Mesoscale Discussion | SPC | Lincoln, Lyon, Pipestone, Rock | 2 hr |
Nearby
Tornado Watches in Wisconsin, 2004Tornado Watches in Minnesota, 2004Tornado Watches in Michigan, 2004Every tornado watch in 2004
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.