Alert archive / Illinois / Mesoscale Discussions in 2009
Mesoscale Discussion 39
The Storm Prediction Center issued this mesoscale discussion at Jan 13, 2009, 11:38 PM CST for 4 states. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- Jan 13, 2009, 11:38 PM CST (05:38 UTC)
- Expired
- Jan 14, 2009, 3:45 AM CST
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
All 119 counties
Allamakee County, IA, Benton County, IA, Black Hawk County, IA, Bremer County, IA, Buchanan County, IA, Butler County, IA, Cedar County, IA, Chickasaw County, IA, Clayton County, IA, Clinton County, IA, Delaware County, IA, Des Moines County, IA, Dubuque County, IA, Fayette County, IA, Floyd County, IA, Franklin County, IA, Grundy County, IA, Hardin County, IA, Henry County, IA, Howard County, IA, Iowa County, IA, Jackson County, IA, Jasper County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Lee County, IA, Linn County, IA, Louisa County, IA, Mahaska County, IA, Marshall County, IA, Muscatine County, IA, Poweshiek County, IA, Scott County, IA, Story County, IA, Tama County, IA, Van Buren County, IA, Wapello County, IA, Washington County, IA, Winneshiek County, IA, Boone County, IL, Bureau County, IL, Carroll County, IL, Cass County, IL, Champaign County, IL, Christian County, IL, Cook County, IL, DeKalb County, IL, DeWitt County, IL, Douglas County, IL, DuPage County, IL, Ford County, IL, Fulton County, IL, Grundy County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Iroquois County, IL, Jo Daviess County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, Knox County, IL, Lake County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Marshall County, IL, Mason County, IL, McDonough County, IL, McHenry County, IL, McLean County, IL, Menard County, IL, Mercer County, IL, Ogle County, IL, Peoria County, IL, Piatt County, IL, Putnam County, IL, Rock Island County, IL, Sangamon County, IL, Schuyler County, IL, Stark County, IL, Stephenson County, IL, Tazewell County, IL, Vermilion County, IL, Warren County, IL, Whiteside County, IL, Will County, IL, Winnebago County, IL, Woodford County, IL, Benton County, IN, Carroll County, IN, Cass County, IN, Clinton County, IN, Fountain County, IN, Fulton County, IN, Howard County, IN, Jasper County, IN, Lake County, IN, Miami County, IN, Montgomery County, IN, Newton County, IN, Porter County, IN, Pulaski County, IN, Starke County, IN, Tippecanoe County, IN, Tipton County, IN, Wabash County, IN, Warren County, IN, White County, IN, Crawford County, WI, Grant County, WI, Green County, WI, Iowa County, WI, Lafayette County, WI, Rock County, WI
The radar
The Chicago radar (KLOT), 103 km from the middle of the area, began a volume at 05:44 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, 5.6 hours before the alert went out and 98 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
- 1711 m above ground
- 0-6 km bulk shear
- 61 kt
- 0-1 km storm-relative helicity
- 25 m²/s²
- 0-3 km storm-relative helicity
- 182 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 140538
SWOMCD
SPC MCD 140538
INZ000-ILZ000-WIZ000-IAZ000-MOZ000-140945-
MESOSCALE DISCUSSION 0039
NWS STORM PREDICTION CENTER NORMAN OK
1138 PM CST TUE JAN 13 2009
AREAS AFFECTED...ERN IA...SWRN WI...NRN IL...NWRN INDIANA
CONCERNING...HEAVY SNOW
VALID 140538Z - 140945Z
A SWATH OF MODERATE TO HEAVY SNOWFALL WILL CONTINUE TO MOVE ESEWD
BEFORE WEAKENING OVER NWRN/CNTRL INDIANA NEAR 12Z. INCH AN HOUR
RATES WILL BE LIKELY MAINLY ACROSS ERN IA AND NWRN/CNTRL IL.
A VORT MAX ROTATING AROUND THE BACKSIDE OF A LARGER SCALE TROUGH IS
NOW PRESSING ESEWD INTO SWRN WI/IL. MODERATE TO HEAVY SNOWFALL HAS
BEEN OBSERVED OVER ERN IA...AND THE HEAVIEST SNOW BAND IS NOW
ORIENTED N-S NEAR THE IA/IL BORDER AND MOVING EWD. DESPITE VERY LOW
PWAT AND AVAILABLE MOISTURE...ISENTROPIC LIFT IN COMBINATION WITH
SUPPORT FROM THE VORT MAX IS CONTRIBUTING TO VERTICAL MOTION AND
AFOREMENTIONED SNOWFALL RATES. 05Z SURFACE ANALYSIS REFLECTS A WEAK
WARM FRONT EXTENDING EWD FROM A SURFACE LOW IN WRN IA...RUNNING
ALONG THE IA/MO BORDERS AND INTO CNTRL IL. VAD WIND PROFILE DATA
SUGGESTS THE STRONGEST LOW LEVEL WARM ADVECTION IS JUST N OF THIS
FRONT IN A SMALL AREA FROM ERN IA INTO CNTRL/NWRN IL. EXPECT THE
HIGHEST ACCUMULATIONS TO BE IN THESE AREAS OVER THE NEXT FEW HOURS.
RATES WILL GRADUALLY DECREASE AS THE LOW AND ASSOCIATED ISENTROPIC
LIFT BEGIN TO WEAKEN.
..HURLBUT.. 01/14/2009
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
...NOTICE...
SPC WINTER WEATHER MESOSCALE DISCUSSIONS WILL BE ISSUED ON A
SCHEDULED BASIS FROM DECEMBER 1 THROUGH FEBRUARY 28...FOUR
TIMES A DAY...AROUND 00 UTC...06 UTC...12 UTC...AND 18 UTC
FOR SIGNIFICANT SHORT RANGE WINTER WEATHER EVENTS.
ATTN...WFO...IWX...IND...LOT...ILX...MKX...LSX...DVN...ARX...
DMX...
LAT...LON 40198575 39528924 40519195 42009349 42919341 43479215
43139007 42418805 41608690 40938580 40198575SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jan 13, 6:12 PM CST | Mesoscale Discussion | SPC | Henderson, Mercer, Rock Island | 4 hr |
| Jan 14, 4:00 PM CST | Mesoscale Discussion | SPC | Lake, LaPorte, Marshall, Porter, Saint Joseph, Starke | 6 hr |
Nearby
Mesoscale Discussions in Illinois, 2009Mesoscale Discussions in Iowa, 2009Mesoscale Discussions in Indiana, 2009Every mesoscale discussion in 2009
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.