Alert archive / Iowa / Mesoscale Discussions in 2007
Mesoscale Discussion 2002
The Storm Prediction Center issued this mesoscale discussion at Sep 21, 2007, 6:17 PM CDT for 9 counties in Illinois; 22 counties in Iowa; 13 counties in Wisconsin. It was in force for 88 min.
The area
The outline as issued.
The facts
- Issued
- Sep 21, 2007, 6:17 PM CDT (23:17 UTC)
- Expired
- Sep 21, 2007, 7:45 PM CDT
- In force
- 88 min
- Issued by
- the Storm Prediction Center
All 44 counties
Benton County, IA, Cedar County, IA, Clinton County, IA, Delaware County, IA, Des Moines County, IA, Dubuque County, IA, Henry County, IA, Iowa County, IA, Jackson County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Linn County, IA, Louisa County, IA, Mahaska County, IA, Monroe County, IA, Muscatine County, IA, Poweshiek County, IA, Scott County, IA, Wapello County, IA, Washington County, IA, Carroll County, IL, Henry County, IL, Jo Daviess County, IL, Mercer County, IL, Ogle County, IL, Rock Island County, IL, Stephenson County, IL, Whiteside County, IL, Winnebago County, IL, Columbia County, WI, Dane County, WI, Dodge County, WI, Grant County, WI, Green County, WI, Iowa County, WI, Jefferson County, WI, Lafayette County, WI, Richland County, WI, Rock County, WI, Sauk County, WI, Walworth County, WI, Washington County, WI
The radar
The Quad Cities radar (KDVN), 98 km from the middle of the area, began a volume at 23:19 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 nearest sounding before it
Davenport, (KDVN), launched 12:00Z, 11.3 hours before the alert went out and 96 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1379 m above ground
- 0-6 km bulk shear
- 21 kt
- 0-1 km storm-relative helicity
- 37 m²/s²
- 0-3 km storm-relative helicity
- 67 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 ACUS11 KWNS 212317 SWOMCD SPC MCD 212317 WIZ000-ILZ000-IAZ000-220045- MESOSCALE DISCUSSION 2002 NWS STORM PREDICTION CENTER NORMAN OK 0617 PM CDT FRI SEP 21 2007 AREAS AFFECTED...EASTERN/SOUTHERN IA AND SOUTHERN WI/NORTHWEST IL CONCERNING...SEVERE THUNDERSTORM WATCH 680... VALID 212317Z - 220045Z THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 680 CONTINUES. VALID PORTION OF SEVERE THUNDERSTORM WATCH 680 CONTINUES UNTIL 04Z...WITH A CONTINUED RISK OF DAMAGING WIND GUSTS AND SOME LARGE HAIL. DOWNSTREAM...ALTHOUGH UNCERTAINTIES EXIST...WILL MONITOR FOR THE POSSIBILITY OF AN ADDITIONAL SEVERE THUNDERSTORM WATCH ACROSS THE REMAINDER OF EASTERN IA/SOUTHERN WI INTO NORTHWEST IL. LARGELY TIED TO SYNOPTIC COLD FRONT...DISTINCT SQUALL LINE CONTINUES TO ADVANCE EASTWARD ACROSS SOUTHWEST WI AND EASTERN/SOUTHERN IA EARLY THIS EVENING...ROUGHLY FROM NEAR VOLK FIELD/CAMP DOUGLAS WI TO WATERLOO/LAMONI IA AS OF 2250Z. THIS LINE HAS A HISTORY OF WIND DAMAGE...ESPECIALLY ACROSS SOUTHWEST WI/NORTHEAST IA. ALTHOUGH SEVERE THREAT WILL CONTINUE THE NEXT FEW HOURS WITH THE SQUALL LINE...MAIN CONCERN/UNCERTAINTIES REGARDING THE EAST EXTENT OF THE SEVERE POTENTIAL EAST OF WW 680 REVOLVE AROUND A DRY DOWNSTREAM AIRMASS AND WARM AIR ALOFT /REFERENCE 18Z SPECIAL DAVENPORT IA RAOB/...WITH 50-55 F SURFACE DEWPOINTS CURRENTLY ALONG/EAST OF THE MISSISSIPPI RIVER IN NORTHERN IL/SOUTHEAST WI. HOWEVER...FORCED NATURE OF THE SQUALL LINE/NARROW PRE-FRONTAL CHANNEL OF LOW LEVEL MOISTURE INFLUX SUGGEST AN ISOLATED SEVERE THREAT CANNOT BE RULED OUT EAST OF EXISTING WW 680...AND THUS WILL CONTINUE TO MONITOR TRENDS FOR THE POSSIBILITY OF AN ADDITIONAL WATCH DOWNSTREAM. ..GUYER.. 09/21/2007 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LOT...ILX...MKX...DVN...ARX...DMX... 43599033 43778916 43638798 42648853 41458989 40769106 40789347 42059225
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 20, 8:40 PM CDT | Mesoscale Discussion | SPC | Lyon | 95 min |
| Sep 21, 3:17 PM CDT | Mesoscale Discussion | SPC | Allamakee, Benton, Black Hawk, Bremer, Buchanan, Butler and 24 more | 88 min |
| Sep 21, 3:53 PM CDT | Severe Thunderstorm Watch | SPC | Adair, Allamakee, Benton, Black Hawk, Boone, Bremer and 26 more | 4 hr |
| Sep 20, 11:09 PM CDT | Mesoscale Discussion | SPC | Barron, Burnett, Chippewa, Clark, Dunn, Eau Claire and 9 more | 81 min |
| Sep 20, 11:13 PM CDT | Severe Thunderstorm Watch | SPC | Ashland, Bayfield, Burnett, Douglas, Iron, Price and 2 more | 7 hr |
| Sep 21, 3:08 AM CDT | Mesoscale Discussion | SPC | Ashland, Bayfield, Burnett, Douglas, Iron, Price and 2 more | 2 hr |
| Sep 21, 6:04 AM CDT | Severe Thunderstorm Watch | SPC | Ashland, Barron, Bayfield, Burnett, Chippewa, Douglas and 11 more | 5 hr |
| Sep 21, 10:24 AM CDT | Mesoscale Discussion | SPC | Adams, Brown, Calumet, Clark, Columbia, Dodge and 27 more | 66 min |
| Sep 21, 1:34 PM CDT | Mesoscale Discussion | SPC | Adams, Ashland, Barron, Bayfield, Buffalo, Burnett and 30 more | 116 min |
| Sep 21, 2:46 PM CDT | Tornado Watch | SPC | Adams, Ashland, Bayfield, Chippewa, Clark, Eau Claire and 25 more | 8 hr |
| Sep 21, 6:49 PM CDT | Mesoscale Discussion | SPC | Brown, Door, Kewaunee, Manitowoc, Sheboygan | 86 min |
Nearby
Mesoscale Discussions in Iowa, 2007Mesoscale Discussions in Wisconsin, 2007Mesoscale Discussions in Illinois, 2007Every mesoscale discussion 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.