Alert archive / Kentucky / Mesoscale Discussions in 2011

Mesoscale Discussion 644

April 27, 20115 states

The Storm Prediction Center issued this mesoscale discussion at Apr 27, 2011, 9:22 PM EDT for 5 states. It was in force for 53 min.

The area

The outline as issued.

The facts

Issued
Apr 27, 2011, 9:22 PM EDT (01:22 UTC)
Expired
Apr 27, 2011, 10:15 PM EDT
In force
53 min
Issued by
the Storm Prediction Center
All 235 counties

Adams County, IN, Bartholomew County, IN, Blackford County, IN, Boone County, IN, Brown County, IN, Carroll County, IN, Cass County, IN, Clark County, IN, Clay County, IN, Clinton County, IN, Crawford County, IN, Daviess County, IN, Dearborn County, IN, Decatur County, IN, Delaware County, IN, Dubois County, IN, Fayette County, IN, Floyd County, IN, Fountain County, IN, Franklin County, IN, Grant County, IN, Greene County, IN, Hamilton County, IN, Hancock County, IN, Harrison County, IN, Hendricks County, IN, Henry County, IN, Howard County, IN, Huntington County, IN, Jackson County, IN, Jay County, IN, Jefferson County, IN, Jennings County, IN, Johnson County, IN, Knox County, IN, Lawrence County, IN, Madison County, IN, Marion County, IN, Martin County, IN, Miami County, IN, Monroe County, IN, Montgomery County, IN, Morgan County, IN, Ohio County, IN, Orange County, IN, Owen County, IN, Parke County, IN, Perry County, IN, Pike County, IN, Putnam County, IN, Randolph County, IN, Ripley County, IN, Rush County, IN, Scott County, IN, Shelby County, IN, Spencer County, IN, Sullivan County, IN, Switzerland County, IN, Tippecanoe County, IN, Tipton County, IN, Union County, IN, Vermillion County, IN, Vigo County, IN, Wabash County, IN, Washington County, IN, Wayne County, IN, Wells County, IN, Adair County, KY, Allen County, KY, Anderson County, KY, Barren County, KY, Bath County, KY, Bell County, KY, Boone County, KY, Bourbon County, KY, Boyd County, KY, Boyle County, KY, Bracken County, KY, Breathitt County, KY, Breckinridge County, KY, Bullitt County, KY, Butler County, KY, Campbell County, KY, Carroll County, KY, Carter County, KY, Casey County, KY, Clark County, KY, Clay County, KY, Clinton County, KY, Cumberland County, KY, Daviess County, KY, Edmonson County, KY, Elliott County, KY, Estill County, KY, Fayette County, KY, Fleming County, KY, Floyd County, KY, Franklin County, KY, Gallatin County, KY, Garrard County, KY, Grant County, KY, Grayson County, KY, Green County, KY, Greenup County, KY, Hancock County, KY, Hardin County, KY, Harlan County, KY, Harrison County, KY, Hart County, KY, Henry County, KY, Jackson County, KY, Jefferson County, KY, Jessamine County, KY, Johnson County, KY, Kenton County, KY, Knott County, KY, Knox County, KY, Larue County, KY, Laurel County, KY, Lawrence County, KY, Lee County, KY, Leslie County, KY, Letcher County, KY, Lewis County, KY, Lincoln County, KY, Logan County, KY, Madison County, KY, Magoffin County, KY, Marion County, KY, Martin County, KY, Mason County, KY, McCreary County, KY, McLean County, KY, Meade County, KY, Menifee County, KY, Mercer County, KY, Metcalfe County, KY, Monroe County, KY, Montgomery County, KY, Morgan County, KY, Muhlenberg County, KY, Nelson County, KY, Nicholas County, KY, Ohio County, KY, Oldham County, KY, Owen County, KY, Owsley County, KY, Pendleton County, KY, Perry County, KY, Pike County, KY, Powell County, KY, Pulaski County, KY, Robertson County, KY, Rockcastle County, KY, Rowan County, KY, Russell County, KY, Scott County, KY, Shelby County, KY, Simpson County, KY, Spencer County, KY, Taylor County, KY, Todd County, KY, Trimble County, KY, Warren County, KY, Washington County, KY, Wayne County, KY, Whitley County, KY, Wolfe County, KY, Woodford County, KY, Adams County, OH, Allen County, OH, Auglaize County, OH, Brown County, OH, Butler County, OH, Champaign County, OH, Clark County, OH, Clermont County, OH, Clinton County, OH, Crawford County, OH, Darke County, OH, Delaware County, OH, Fairfield County, OH, Fayette County, OH, Franklin County, OH, Greene County, OH, Hamilton County, OH, Hancock County, OH, Hardin County, OH, Highland County, OH, Hocking County, OH, Knox County, OH, Lawrence County, OH, Licking County, OH, Logan County, OH, Madison County, OH, Marion County, OH, Mercer County, OH, Miami County, OH, Montgomery County, OH, Morrow County, OH, Pickaway County, OH, Pike County, OH, Preble County, OH, Putnam County, OH, Richland County, OH, Ross County, OH, Scioto County, OH, Shelby County, OH, Union County, OH, Van Wert County, OH, Warren County, OH, Wyandot County, OH, Buchanan County, VA, City of Bristol, VA, City of Norton, VA, Dickenson County, VA, Lee County, VA, Russell County, VA, Scott County, VA, Smyth County, VA, Tazewell County, VA, Washington County, VA, Wise County, VA, Boone County, WV, Cabell County, WV, Fayette County, WV, Kanawha County, WV, Lincoln County, WV, Logan County, WV, McDowell County, WV, Mingo County, WV, Putnam County, WV, Raleigh County, WV, Wayne County, WV, Wyoming County, WV

The radar

The Cincinnati radar (KILN), 92 km from the middle of the area, began a volume at 01:22 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

Cncnati-Daytn, OH (KILN), launched 00:00Z, 1.4 hours before the alert went out and 93 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.

Skew-T log-pSkew-T log-p diagram, Cncnati-Daytn, OH at 00:00Z on 2011-04-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Cncnati-Daytn, OH at 00:00Z on 2011-04-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 96 square meters per square second.1939587897117Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
775 m above ground
0-6 km bulk shear
70 kt
0-1 km storm-relative helicity
96 m²/s²
0-3 km storm-relative helicity
521 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.5

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

523 
ACUS11 KWNS 280122
SWOMCD
SPC MCD 280122 
WVZ000-VAZ000-NCZ000-TNZ000-KYZ000-OHZ000-INZ000-ILZ000-280215-

MESOSCALE DISCUSSION 0644
NWS STORM PREDICTION CENTER NORMAN OK
0822 PM CDT WED APR 27 2011

AREAS AFFECTED...KY...IND...WRN AND CENTRAL OH...WRN WV...AND SWRN
VA

CONCERNING...TORNADO WATCH 239...242...

VALID 280122Z - 280215Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 239...242...CONTINUES.

EARLY-MID EVENING SURFACE ANALYSIS INDICATED AN AREA OF LOW PRESSURE
CONTINUING TO TRACK NEWD INTO SWRN IND ALONG A QUASI-STATIONARY
BOUNDARY WHICH EXTENDED NEWD ACROSS CENTRAL-ERN IND INTO NWRN OH. 
MEANWHILE...A COLD FRONT TRAILED SWD FROM THE LOW THROUGH WRN TN
INTO MS...BISECTING MS GENERALLY FROM NE-SW.

CLOUDINESS ACROSS MUCH WW/S 239 AND 242 HAVE MITIGATED STRONGER
INSTABILITY FROM DEVELOPING WITH THE GREATEST INSTABILITY /MUCAPE TO
AROUND 1000 J PER KG/ EXTENDING ACROSS ERN KY INTO SRN OH.  THIS
CORRIDOR OF INSTABILITY IS LOCATED ALONG A STRONG SLY LLJ /50-70 KT/
WHICH WILL CONTINUE TO PROVIDE NWD MOISTURE ADVECTION/
DESTABILIZATION INTO ERN KY/SRN OH DESPITE THE ONSET OF DIABATIC
COOLING.  GREATEST SEVERE WEATHER THREAT THROUGH THE EVENING SHOULD
BE CONFINED TO THE ERN HALF OF KY INTO PARTS OF SRN OH GIVEN THE
AFOREMENTIONED FACTORS.  HOWEVER...AREAS FARTHER NW-N ALONG THE
TRACK OF THE SURFACE LOW INTO IND WILL HAVE A CONDITIONAL TORNADO
TREAT DESPITE WEAKER INSTABILITY.  ISALLOBARIC EFFECT OF THE SURFACE
WINDS DUE TO SURFACE PRESSURE FALLS OVER IND INTO WRN KY SHOULD
MAINTAIN A SELY COMPONENT AND ENHANCE LOW LEVEL SHEAR...ESPECIALLY
ALONG AND ESE OF THE SURFACE LOW TRACK.

..PETERS.. 04/28/2011

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...RNK...RLX...CLE...MRX...JKL...ILN...LMK...IWX...
OHX...IND...PAH...ILX...

LAT...LON   36678708 36968758 38198723 38688755 40138747 40948636
            40998434 41138354 40898241 40358222 39408238 39008280
            38708252 38598160 38158105 37988077 37368131 36748140
            36558171 36588489 36678708

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 28, 1:38 PM EDTMesoscale DiscussionSPCBartholomew, Brown, Clark, Clay, Crawford, Daviess and 42 more97 min
Apr 28, 12:51 AM EDTMesoscale DiscussionSPCAllen, Fulton, Hancock, Henry, Lucas, Putnam and 1 more54 min
Apr 28, 3:19 AM EDTMesoscale DiscussionSPCAshland, Belmont, Carroll, Columbiana, Coshocton, Crawford and 22 more56 min
Apr 27, 10:12 PM EDTMesoscale DiscussionSPCAlbemarle, Alleghany, Amelia, Amherst, Appomattox, Arlington and 68 more63 min
Apr 28, 12:27 AM EDTMesoscale DiscussionSPCAlbemarle, Alleghany, Amherst, Appomattox, Arlington, Augusta and 65 more63 min
Apr 28, 12:34 AM EDTMesoscale DiscussionSPCBuchanan, Dickenson, Lee, Russell, Scott, Tazewell and 3 more26 min
Apr 28, 12:41 AM EDTTornado WatchSPCAlbemarle, Alleghany, Amelia, Amherst, Appomattox, Arlington and 78 more7 hr
Apr 28, 7:38 AM EDTTornado WatchSPCAccomack, Albemarle, Amelia, Amherst, Appomattox, Arlington and 83 more7 hr
Apr 28, 10:44 AM EDTMesoscale DiscussionSPCAlbemarle, Amelia, Amherst, Appomattox, Arlington, Bedford and 69 more61 min
Apr 28, 2:00 PM EDTMesoscale DiscussionSPCAccomack, Amelia, Arlington, Brunswick, Caroline, Charles City and 47 more60 min
Apr 28, 2:41 PM EDTTornado WatchSPCAccomack, Charles City, Essex, Gloucester, Greensville, Isle of Wight and 30 more6 hr
Apr 28, 6:33 PM EDTMesoscale DiscussionSPCAccomack, Charles City, Essex, Gloucester, Greensville, Henrico and 31 more57 min

Nearby

Mesoscale Discussions in Kentucky, 2011Mesoscale Discussions in Indiana, 2011Mesoscale Discussions in Ohio, 2011Every mesoscale discussion in 2011

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.