Alert archive / Kentucky / Mesoscale Discussions in 2012
Mesoscale Discussion 693
The Storm Prediction Center issued this mesoscale discussion at May 4, 2012, 11:36 AM CDT for 4 states. It was in force for 84 min.
The area
The outline as issued.
The facts
- Issued
- May 4, 2012, 11:36 AM CDT (16:36 UTC)
- Expired
- May 4, 2012, 1:00 PM CDT
- In force
- 84 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 80%
All 76 counties
Clay County, IL, Clinton County, IL, Edwards County, IL, Franklin County, IL, Gallatin County, IL, Hamilton County, IL, Hardin County, IL, Jackson County, IL, Jefferson County, IL, Johnson County, IL, Lawrence County, IL, Marion County, IL, Perry County, IL, Pope County, IL, Randolph County, IL, Richland County, IL, Saline County, IL, Union County, IL, Wabash County, IL, Washington County, IL, Wayne County, IL, White County, IL, Williamson County, IL, Clark County, IN, Crawford County, IN, Daviess County, IN, Dubois County, IN, Floyd County, IN, Gibson County, IN, Harrison County, IN, Knox County, IN, Martin County, IN, Orange County, IN, Perry County, IN, Pike County, IN, Posey County, IN, Spencer County, IN, Vanderburgh County, IN, Warrick County, IN, Washington County, IN, Anderson County, KY, Barren County, KY, Breckinridge County, KY, Bullitt County, KY, Butler County, KY, Crittenden County, KY, Daviess County, KY, Edmonson County, KY, Franklin County, KY, Grayson County, KY, Green County, KY, Hancock County, KY, Hardin County, KY, Hart County, KY, Henderson County, KY, Hopkins County, KY, Jefferson County, KY, Larue County, KY, Marion County, KY, McLean County, KY, Meade County, KY, Mercer County, KY, Metcalfe County, KY, Muhlenberg County, KY, Nelson County, KY, Ohio County, KY, Oldham County, KY, Shelby County, KY, Spencer County, KY, Taylor County, KY, Union County, KY, Warren County, KY, Washington County, KY, Webster County, KY, Woodford County, KY, Perry County, MO
The radar
The Evansville,IN radar (KVWX), 11 km from the middle of the area, began a volume at 16:36 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
Lincoln, IL (KILX), launched 12:00Z, 4.6 hours before the alert went out and 231 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
- 1160 m above ground
- 0-6 km bulk shear
- 36 kt
- 0-1 km storm-relative helicity
- 34 m²/s²
- 0-3 km storm-relative helicity
- 170 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
279 ACUS11 KWNS 041637 SWOMCD SPC MCD 041636 KYZ000-INZ000-ILZ000-MOZ000-041800- MESOSCALE DISCUSSION 0693 NWS STORM PREDICTION CENTER NORMAN OK 1136 AM CDT FRI MAY 04 2012 AREAS AFFECTED...SRN IL...SRN IND...WRN/CNTRL KY CONCERNING...SEVERE POTENTIAL...WATCH LIKELY VALID 041636Z - 041800Z PROBABILITY OF WATCH ISSUANCE...80 PERCENT SUMMARY...THUNDERSTORMS ARE EXPECTED TO INCREASE IN AREAL COVERAGE ACROSS PORTIONS OF THE OH VALLEY THIS AFTERNOON. STRONG WINDS AND HAIL ARE POSSIBLE WITH THIS ACTIVITY AND A SEVERE THUNDERSTORM WATCH WILL LIKELY BE WARRANTED. DISCUSSION...REMNANTS OF OVERNIGHT MCS ACTIVITY HAVE PROGRESSED ACROSS THE MID MS VALLEY LATE THIS MORNING WITH SEVERAL NOTABLE STRONG UPDRAFTS AFFILIATED IN PROXIMITY TO A DECAYING MCV OVER SWRN IL. SUBSTANTIAL CONVECTIVE DEBRIS/OUTFLOW HAS SPREAD ACROSS MUCH OF CNTRL IL/IND BUT THE AIRMASS ALONG THE OH RIVER IS BEGINNING TO DESTABILIZE SUBSTANTIALLY DUE TO PRONOUNCED HEATING THROUGH PARTIAL SUNSHINE. LATEST DATA SUGGESTS A BELT OF STRONGER MID LEVEL FLOW EXTENDS ACROSS MO ALONG THE OH RIVER WHICH SHOULD ENCOURAGE MULTI-CELL STORM GROWTH/ORGANIZATION AS UPDRAFTS MATURE. LATEST THINKING IS STRONG THUNDERSTORMS OVER SWRN IL WILL GRADUALLY INCREASE AS THEY PROPAGATE ESEWD TOWARD NWRN KY AND OTHER STORMS SHOULD DEVELOP DOWNSTREAM OVER THE NEXT FEW HOURS ALONG THE SRN FRINGE OF OLD CONVECTION/OUTFLOW. STRONG WINDS AND LARGE HAIL WILL BE THE PRIMARY SEVERE THREATS WITH THESE STORMS. ..DARROW/MEAD.. 05/04/2012 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...LMK...IND...PAH...ILX...LSX... LAT...LON 38838979 38848689 38168459 36768565 37619000 38838979
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 3, 7:09 PM CDT | Tornado Watch | SPC | Adams, Brown, Pike, Rock Island | 6 hr |
| May 3, 10:29 PM CDT | Mesoscale Discussion | SPC | Cook, DeKalb, DuPage, Ford, Grundy, Iroquois and 7 more | 61 min |
| May 3, 11:18 PM CDT | Mesoscale Discussion | SPC | Adams, Brown, Bureau, Cass, DeWitt, Fulton and 22 more | 27 min |
| May 3, 11:34 PM CDT | Severe Thunderstorm Watch | SPC | Bureau, Cass, Champaign, DeWitt, Ford, Fulton and 25 more | 5 hr |
| May 4, 12:53 AM CDT | Severe Thunderstorm Watch | SPC | Adams, Brown | 4 hr |
| May 4, 2:16 AM CDT | Mesoscale Discussion | SPC | Adams, Brown, Bureau, Cass, DeWitt, Ford and 25 more | 119 min |
| May 4, 1:29 PM CDT | Severe Thunderstorm Watch | SPC | Edwards, Wabash, White | 5 hr |
| May 4, 3:16 PM CDT | Mesoscale Discussion | SPC | Clark, Crawford, Daviess, Dubois, Floyd, Gibson and 19 more | 59 min |
| May 4, 6:52 PM CDT | Mesoscale Discussion | SPC | Boone, Delaware, Fayette, Franklin, Hamilton, Hancock and 12 more | 53 min |
Nearby
Mesoscale Discussions in Kentucky, 2012Mesoscale Discussions in Illinois, 2012Mesoscale Discussions in Indiana, 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.