Alert archive / Michigan / Mesoscale Discussions in 2003
Mesoscale Discussion 1602
The Storm Prediction Center issued this mesoscale discussion at Jul 4, 2003, 7:25 AM CDT for Cook County, Lake County, McHenry County, Illinois; 18 counties in Michigan; 13 counties in Wisconsin. It was in force for 95 min.
The area
The outline as issued.
The facts
- Issued
- Jul 4, 2003, 7:25 AM CDT (12:25 UTC)
- Expired
- Jul 4, 2003, 9:00 AM CDT
- In force
- 95 min
- Issued by
- the Storm Prediction Center
All 34 counties
Cook County, IL, Lake County, IL, McHenry County, IL, Allegan County, MI, Barry County, MI, Benzie County, MI, Cass County, MI, Kalamazoo County, MI, Kent County, MI, Lake County, MI, Manistee County, MI, Mason County, MI, Mecosta County, MI, Muskegon County, MI, Newaygo County, MI, Oceana County, MI, Osceola County, MI, Ottawa County, MI, Saint Joseph County, MI, Van Buren County, MI, Wexford County, MI, Brown County, WI, Calumet County, WI, Fond du Lac County, WI, Kenosha County, WI, Kewaunee County, WI, Manitowoc County, WI, Milwaukee County, WI, Outagamie County, WI, Ozaukee County, WI, Racine County, WI, Sheboygan County, WI, Washington County, WI, Waukesha County, WI
The radar
The Grand Rapids radar (KGRR), 98 km from the middle of the area, began a volume at 12:24 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Green Bay/Straub, WI (KGRB), launched 12:00Z, 0.4 hours before the alert went out and 193 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
- 1540 J/kg
- Mixed-layer CIN
- -96 J/kg
- Mixed-layer LCL
- 1004 m above ground
- 0-6 km bulk shear
- 23 kt
- 0-1 km storm-relative helicity
- 33 m²/s²
- 0-3 km storm-relative helicity
- 47 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.2
The text
As transmitted, in the capitals the NWS used until 2016.
680 ACUS11 KWNS 041225 SWOMCD SPC MCD 041225 MIZ000-WIZ000-ILZ000-041400- MESOSCALE DISCUSSION 1602 NWS STORM PREDICTION CENTER NORMAN OK 0725 AM CDT FRI JUL 04 2003 AREAS AFFECTED...SE WI/NE IL/N IND/W LOWER MI CONCERNING...SEVERE THUNDERSTORM WATCH 632... VALID 041225Z - 041400Z CONVECTIVE LINE ACROSS ERN WI/NERN IL WILL CONTINUE TO MOVE EWD AT 40 KT WITH THE POTENTIAL FOR ISOLATED DAMAGING WIND GUSTS OVER THE NEXT FEW HOURS. NEW WW MAY BECOME NECESSARY OVER WESTERN LOWER MI IF THE LINE MAINTAINS ORGANIZATION. LINEAR MCS HAS WEAKENED IN INTENSITY OVER THE LAST HOUR OR SO. HOWEVER...THE AIRMASS AHEAD OF THE LINE REMAINED MODERATE UNSTABLE WITH MLCAPE OF 1000 TO 1500 J/KG. AS A RESULT...THE LINE SHOULD CONTINUE ACROSS LAKE MICHIGAN AND INTO LOWER MI. ALTHOUGH DEEP LAYER SHEAR HAS WEAKENED SOME...MID-LEVEL FLOW WAS STILL AROUND 30 KT. AS THE SFC TEMPS WARM AHEAD OF THE LINE...REINTENSIFICATION WILL BE POSSIBLE. IN ADDITION...AS THE LINE MOVES OVER LAKE MICHIGAN...A LACK OF FRICTION OVER THE WATER SFC MAY RESULT IN AN ENHANCEMENT OF THE GUST FRONT AHEAD OF THE LINE. IF THE LINE CAN RETAIN INTENSITY...THREAT OF WIND DAMAGE MAY EXIST AS THE LINE MOVES OVER LAKE MICHIGAN AND BACK INLAND OVER LOWER MI. ..BROYLES.. 07/04/2003 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...APX...IWX...GRR...GRB...LOT...MKX... 41798683 41968842 43228862 44588847 44758688 44568531 43638519 42478525 41868545
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 4, 1:15 AM CDT | Severe Thunderstorm Watch | SPC | Carroll, Jo Daviess, Lee, Ogle, Rock Island, Stephenson and 2 more | 6 hr |
| Jul 4, 3:27 AM CDT | Mesoscale Discussion | SPC | Boone, Carroll, Cook, DeKalb, DuPage, Grundy and 12 more | 93 min |
| Jul 4, 5:20 AM CDT | Severe Thunderstorm Watch | SPC | Boone, Cook, DeKalb, DuPage, Kane, Lake and 1 more | 4 hr |
| Jul 4, 12:48 PM CDT | Mesoscale Discussion | SPC | Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 26 more | 117 min |
| Jul 4, 2:20 PM CDT | Severe Thunderstorm Watch | SPC | Bureau, Champaign, DeWitt, Ford, Fulton, Grundy and 21 more | 6 hr |
| Jul 4, 3:29 PM CDT | Mesoscale Discussion | SPC | Champaign, DeWitt, Douglas, Ford, Iroquois, Kankakee and 4 more | 2 hr |
| Jul 4, 5:07 PM CDT | Mesoscale Discussion | SPC | Bond, Clark, Clay, Clinton, Coles, Crawford and 27 more | 53 min |
| Jul 4, 6:29 PM CDT | Mesoscale Discussion | SPC | Bureau, Champaign, Clark, Coles, DeWitt, Douglas and 29 more | 61 min |
| Jul 4, 7:50 AM CDT | Severe Thunderstorm Watch | SPC | Allegan, Barry, Berrien, Branch, Calhoun, Cass and 18 more | 3 hr |
| Jul 4, 9:28 AM CDT | Mesoscale Discussion | SPC | Barry, Branch, Calhoun, Clinton, Eaton, Genesee and 20 more | 2 hr |
| Jul 4, 9:45 AM CDT | Severe Thunderstorm Watch | SPC | Clinton, Genesee, Gratiot, Hillsdale, Ingham, Jackson and 11 more | 5 hr |
| Jul 4, 12:04 PM CDT | Mesoscale Discussion | SPC | Berrien, Branch, Calhoun, Cass, Hillsdale, Jackson and 10 more | 116 min |
| Jul 3, 11:23 PM CDT | Mesoscale Discussion | SPC | Adams, Barron, Buffalo, Chippewa, Clark, Crawford and 17 more | 97 min |
| Jul 4, 12:42 AM CDT | Mesoscale Discussion | SPC | Barron, Buffalo, Chippewa, Crawford, Dunn, Eau Claire and 9 more | 63 min |
Nearby
Mesoscale Discussions in Michigan, 2003Mesoscale Discussions in Wisconsin, 2003Mesoscale Discussions in Illinois, 2003Every mesoscale discussion in 2003
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.