Alert archive / Iowa / Mesoscale Discussions in 2012
Mesoscale Discussion 147
The Storm Prediction Center issued this mesoscale discussion at Feb 23, 2012, 8:45 PM CST for 17 counties in Illinois; 57 counties in Iowa; 12 counties in Wisconsin. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Feb 23, 2012, 8:45 PM CST (02:45 UTC)
- Expired
- Feb 24, 2012, 1:45 AM CST
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
All 86 counties
Adair County, IA, Adams County, IA, Appanoose County, IA, Audubon County, IA, Benton County, IA, Black Hawk County, IA, Boone County, IA, Buchanan County, IA, Cass County, IA, Cedar County, IA, Clarke County, IA, Clayton County, IA, Clinton County, IA, Dallas County, IA, Davis County, IA, Decatur County, IA, Delaware County, IA, Des Moines County, IA, Dubuque County, IA, Fayette County, IA, Greene County, IA, Grundy County, IA, Guthrie County, IA, Hardin County, IA, Henry County, IA, Iowa County, IA, Jackson County, IA, Jasper County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Linn County, IA, Louisa County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Monroe County, IA, Montgomery County, IA, Muscatine County, IA, Page County, IA, Polk County, IA, Pottawattamie County, IA, Poweshiek County, IA, Ringgold County, IA, Scott County, IA, Story County, IA, Tama County, IA, Taylor County, IA, Union County, IA, Van Buren County, IA, Wapello County, IA, Warren County, IA, Washington County, IA, Wayne County, IA, Boone County, IL, Bureau County, IL, Carroll County, IL, DeKalb County, IL, DuPage County, IL, Henry County, IL, Jo Daviess County, IL, Kane County, IL, Lake County, IL, Lee County, IL, McHenry County, IL, Mercer County, IL, Ogle County, IL, Rock Island County, IL, Stephenson County, IL, Whiteside County, IL, Winnebago County, IL, Dane County, WI, Grant County, WI, Green County, WI, Iowa County, WI, Jefferson County, WI, Kenosha County, WI, Lafayette County, WI, Milwaukee County, WI, Racine County, WI, Rock County, WI, Walworth County, WI, Waukesha County, WI
The radar
The Quad Cities radar (KDVN), 67 km from the middle of the area, began a volume at 02:45 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 00:00Z, 2.8 hours before the alert went out and 72 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
- 484 m above ground
- 0-6 km bulk shear
- 70 kt
- 0-1 km storm-relative helicity
- 82 m²/s²
- 0-3 km storm-relative helicity
- 697 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
167
ACUS11 KWNS 240245
SWOMCD
SPC MCD 240245
ILZ000-WIZ000-IAZ000-MOZ000-240745-
MESOSCALE DISCUSSION 0147
NWS STORM PREDICTION CENTER NORMAN OK
0845 PM CST THU FEB 23 2012
AREAS AFFECTED...SRN IA...NRN IL...SRN WI
CONCERNING...HEAVY SNOW
VALID 240245Z - 240745Z
A BAND OF SNOWFALL...ASSOCIATED WITH A NEGATIVELY TILTED SHORTWAVE
TROUGH AND ATTENDANT SFC LOW...WILL RESULT IN BRIEF PERIODS OF MOD
TO HVY SNOW ACROSS THE UPPER MIDWEST.
A NEGATIVELY TILTED SHORTWAVE WILL CONTINUE TO PROGRESS EWD ACROSS
THE MIDWEST DURING THE NEXT FEW HOURS. SFC LOW ASSOCIATED WITH THIS
SHORTWAVE IS CURRENTLY CENTERED OVER S IL AND FAR W KY. 850 MB
FRONTOGENESIS AND ITS ASSOCIATED SNOW BAND... CURRENTLY LOCATED
ACROSS SRN IA EWD TO SRN MI...IS EXPECTED TO DRIFT SWD AND WEAKEN
OVER THE NEXT FEW HOURS AS THE SHORTWAVE TROUGH AND SFC LOW PROGRESS
EWD. A SATURATED DENDRITIC GROWTH ZONE AND EASTERLY FLOW BTW 925-850
MB SHOULD CONTINUE TO PROMOTE BRIEF PERIODS OF MOD TO HVY SNOW
WITHIN THE BAND. HOWEVER..WEAKENING FRONTOGENESIS WITH TIME WILL
RESULT IN A GRADUAL REDUCTION IN SNOWFALL RATES ACROSS IA. FURTHER
E...THE POTENTIAL FOR HIGHER RATES WILL LINGER FOR THE NEXT SEVERAL
HOURS. ADDITIONALLY...QUICK PROGRESSION OF THE SYSTEM SHOULD LIMIT
OVERALL SNOWFALL TOTALS.
..MOSIER/LEITMAN.. 02/24/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LOT...ILX...MKX...DVN...ARX...DMX...EAX...OAX...
LAT...LON 43159094 43298921 43178792 42528754 41978763 41748810
41448918 40889125 40579229 40619522 41249571 41729524
42239403 42729236 43159094Nearby
Mesoscale Discussions in Iowa, 2012Mesoscale Discussions in Illinois, 2012Mesoscale Discussions in Wisconsin, 2012Every mesoscale discussion in 2012
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.