Alert archive / Wisconsin / Mesoscale Discussions in 2012
Mesoscale Discussion 907
The Storm Prediction Center issued this mesoscale discussion at May 26, 2012, 6:31 AM CDT for Boone County, McHenry County, Illinois; 10 counties in Wisconsin. It was in force for 89 min.
The area
The outline as issued.
The facts
- Issued
- May 26, 2012, 6:31 AM CDT (11:31 UTC)
- Expired
- May 26, 2012, 8:00 AM CDT
- In force
- 89 min
- Issued by
- the Storm Prediction Center
Counties Boone County, IL, McHenry County, IL, Dane County, WI, Grant County, WI, Green County, WI, Iowa County, WI, Jefferson County, WI, Kenosha County, WI, Lafayette County, WI, Racine County, WI, Rock County, WI, Walworth County, WI
The radar
The Milwaukee radar (KMKX), 62 km from the middle of the area, began a volume at 11:33 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, 11.5 hours before the alert went out and 163 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
- 1813 m above ground
- 0-6 km bulk shear
- 66 kt
- 0-1 km storm-relative helicity
- 188 m²/s²
- 0-3 km storm-relative helicity
- 490 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.8
The text
As transmitted, in the capitals the NWS used until 2016.
568
ACUS11 KWNS 261132
SWOMCD
SPC MCD 261131
ILZ000-WIZ000-IAZ000-261300-
MESOSCALE DISCUSSION 0907
NWS STORM PREDICTION CENTER NORMAN OK
0631 AM CDT SAT MAY 26 2012
AREAS AFFECTED...PARTS OF NERN IA...SRN WI...NRN IL
CONCERNING...HEAVY RAINFALL
VALID 261131Z - 261300Z
SUMMARY...THUNDERSTORM ACTIVITY WITH LOCALLY HEAVY RAIN MAY PERSIST
THROUGH MID MORNING ACROSS PARTS OF SOUTHERN WISCONSIN/NORTHERN
ILLINOIS. SEVERE POTENTIAL APPEARS LOW.
DISCUSSION...CONVECTION HAS BEEN GENERALLY WEAKENING IN
INTENSITY...BUT SOME MODEL GUIDANCE...INCLUDING THE NCEP SREF...MAY
BE A BIT QUICK WITH DIMINISHMENT/DISSIPATION OF ACTIVITY THIS
MORNING. THE TRAILING EDGE OF STRONGER MID-LEVEL FORCING ASSOCIATED
WITH A WEAK IMPULSE/ CYCLONIC VORTICITY CENTER IS IN THE PROCESS OF
SHIFTING EAST SOUTHEASTWARD OUT OF NORTHEAST IOWA...LIKELY ACROSS
SOUTHWEST AND SOUTH CENTRAL WISCONSIN BY 14-15Z. THIS MAY CONTINUE
TO CONTRIBUTE TO THE MAINTENANCE OF SIGNIFICANT CONVECTIVE
DEVELOPMENT THROUGH MID MORNING. SEVERE POTENTIAL APPEARS LOW...
BUT PERSISTENT/TRAINING STORMS...IN A NEAR SATURATED ENVIRONMENT
WITH PRECIPITABLE WATER IN EXCESS OF 1.5 INCHES...COULD STILL YIELD
HEAVY TO LOCALLY EXCESSIVE RAINFALL IN A CORRIDOR WEST SOUTHWEST
THROUGH SOUTH OF MADISON...INTO LAKE MICHIGAN COASTAL AREAS BETWEEN
CHICAGO AND MILWAUKEE.
..KERR.. 05/26/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LOT...MKX...DVN...ARX...
LAT...LON 43299010 43048884 42888770 42508763 42168847 42338906
42639018 42749126 43299010SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 26, 12:46 AM CDT | Mesoscale Discussion | SPC | Crawford | 89 min |
Nearby
Mesoscale Discussions in Wisconsin, 2012Mesoscale Discussions in Illinois, 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.