Alert archive / Indiana / Mesoscale Discussions in 2011

Mesoscale Discussion 607

April 26, 20114 states

The Storm Prediction Center issued this mesoscale discussion at Apr 26, 2011, 8:35 PM CDT for 4 states. It was in force for 55 min.

The area

The outline as issued.

The facts

Issued
Apr 26, 2011, 8:35 PM CDT (01:35 UTC)
Expired
Apr 26, 2011, 9:30 PM CDT
In force
55 min
Issued by
the Storm Prediction Center
All 67 counties

Crawford County, IL, Edwards County, IL, Gallatin County, IL, Lawrence County, IL, Wabash County, IL, White County, IL, Bartholomew County, IN, Boone County, IN, Brown County, IN, Clark County, IN, Clay County, IN, Crawford County, IN, Daviess County, IN, Decatur County, IN, Dubois County, IN, Fayette County, IN, Floyd County, IN, Fountain County, IN, Franklin County, IN, Gibson County, IN, Greene County, IN, Hamilton County, IN, Hancock County, IN, Harrison County, IN, Hendricks County, IN, Henry County, IN, Jackson County, IN, Jefferson County, IN, Jennings County, IN, Johnson County, IN, Knox County, IN, Lawrence County, IN, Marion County, IN, Martin County, IN, Monroe County, IN, Montgomery County, IN, Morgan County, IN, Orange County, IN, Owen County, IN, Parke County, IN, Perry County, IN, Pike County, IN, Posey County, IN, Putnam County, IN, Ripley County, IN, Rush County, IN, Scott County, IN, Shelby County, IN, Spencer County, IN, Sullivan County, IN, Union County, IN, Vanderburgh County, IN, Vigo County, IN, Warrick County, IN, Washington County, IN, Wayne County, IN, Breckinridge County, KY, Bullitt County, KY, Daviess County, KY, Hancock County, KY, Hardin County, KY, Henderson County, KY, Jefferson County, KY, Meade County, KY, Oldham County, KY, Trimble County, KY, Preble County, OH

The radar

The Evansville,IN radar (KVWX), 86 km from the middle of the area, began a volume at 01:37 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 00:00Z, 1.6 hours before the alert went out and 221 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, Lincoln, IL at 00:00Z on 2011-04-27Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 00:00Z on 2011-04-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 97 square meters per square second.1939587897Sfc1 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
1179 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
97 m²/s²
0-3 km storm-relative helicity
125 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

844 
ACUS11 KWNS 270136
SWOMCD
SPC MCD 270135
OHZ000-INZ000-KYZ000-ILZ000-270230-

MESOSCALE DISCUSSION 0607
NWS STORM PREDICTION CENTER NORMAN OK
0835 PM CDT TUE APR 26 2011

AREAS AFFECTED...SRN IN...PORTIONS OF NRN KY

CONCERNING...TORNADO WATCH 219...

VALID 270135Z - 270230Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 219 CONTINUES.

SVR THREAT ACROSS SRN IND AND FAR NRN KY REMAINS QUITE CONDITIONAL
ATTM...AS THE ENVIRONMENT REMAINS MARGINALLY UNSTABLE AND SFC FLOW
RATHER WEAK. WITH THE LOSS OF DIABATIC HEATING...AND SHORTWAVE
RIDGING OVERHEAD...CONVECTION HAS BEEN SUPPRESSED OVER MUCH OF THE
WW AREA /WITH EXCEPTION TO LEFT SPLITTING STORM THAT MOVED N ACROSS
THE AREA...AND RIGHT-MOVING SUPERCELL NEAR THE OH RIVER VALLEY NOW
OVER N-CNTRL KY/. CONVECTION S OF THE WATCH AREA IS EXPECTED TO
APPROACH THE OH RIVER VALLEY WITHIN THE NEXT FEW HRS. THIS SCENARIO
IS SUPPORTED BY HIGH-RESOLUTION MODELS /INCLUDING WRF-NMM AND
EXPERIMENTAL HRRR GUIDANCE/...WHICH INDICATE THUNDERSTORMS WILL
CONTINUE TO DEVELOP NWD NEAR 03Z NEAR SRN PORTIONS OF THE WATCH
AREA...WITH ACCOMPANYING SVR AND/OR TOR POTENTIAL POSSIBLE. THIS MAY
REQUIRE AN ADDITIONAL WW LATER TONIGHT.

..ROGERS.. 04/27/2011

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

ATTN...WFO...ILN...LMK...IND...PAH...ILX...

LAT...LON   37728847 40148725 40098445 37698578 37728847

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 26, 9:13 PM CDTMesoscale DiscussionSPCAlexander, Gallatin, Hardin, Johnson, Massac, Pope and 5 more62 min
Apr 27, 12:42 PM CDTSevere Thunderstorm WatchSPCAlexander, Hardin, Johnson, Massac, Pope, Pulaski and 1 more5 hr
Apr 27, 3:06 PM CDTMesoscale DiscussionSPCAlexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 10 more54 min
Apr 27, 3:29 PM CDTTornado WatchSPCAlexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more5 hr
Apr 27, 5:27 PM CDTMesoscale DiscussionSPCClark, Crawford, Edwards, Gallatin, Hamilton, Hardin and 7 more63 min
Apr 26, 7:33 PM CDTMesoscale DiscussionSPCAdams, Allen, Blackford, Boone, Carroll, Cass and 35 more57 min
Apr 26, 9:58 PM CDTTornado WatchSPCClark, Crawford, Dubois, Floyd, Harrison, Jefferson and 4 more7 hr
Apr 27, 4:38 PM CDTMesoscale DiscussionSPCClark, Crawford, Floyd, Harrison, Jefferson, Ohio and 4 more37 min
Apr 27, 4:44 PM CDTTornado WatchSPCClark, Crawford, Dubois, Floyd, Harrison, Jefferson and 5 more7 hr
Apr 27, 6:22 PM CDTTornado WatchSPCAdams, Bartholomew, Blackford, Boone, Brown, Carroll and 49 more8 hr
Apr 27, 4:33 AM CDTMesoscale DiscussionSPCAdair, Barren, Boyle, Casey, Clinton, Cumberland and 12 more57 min
Apr 27, 5:07 AM CDTTornado WatchSPCAdair, Allen, Anderson, Barren, Bourbon, Boyle and 28 more5 hr
Apr 27, 7:34 AM CDTTornado WatchSPCBath, Bell, Breathitt, Clay, Elliott, Estill and 21 more4 hr
Apr 27, 8:39 AM CDTMesoscale DiscussionSPCBoyd, Carter, Greenup, Lewis66 min
Apr 27, 2:22 PM CDTMesoscale DiscussionSPCBell, Breathitt, Clay, Floyd, Harlan, Jackson and 11 more83 min
Apr 27, 12:24 PM CDTMesoscale DiscussionSPCAshtabula, Belmont, Carroll, Columbiana, Guernsey, Harrison and 9 more96 min

Nearby

Mesoscale Discussions in Indiana, 2011Mesoscale Discussions in Kentucky, 2011Mesoscale Discussions in Illinois, 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.