Alert archive / Indiana / Mesoscale Discussions in 2016

Mesoscale Discussion 738

May 26, 201615 counties in Illinois; 36 counties in Indiana

The Storm Prediction Center issued this mesoscale discussion at May 26, 2016, 9:05 AM CDT for 15 counties in Illinois; 36 counties in Indiana. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued: May 26, 2016, 9:05 AM CDT (14:05 UTC)
Expired: May 26, 2016, 10:30 AM CDT
In force: 85 min
Issued by: the Storm Prediction Center
Chance of a watch: 20%

All 51 counties

Crawford County, IL, Edwards County, IL, Franklin County, IL, Gallatin County, IL, Hamilton County, IL, Jackson County, IL, Jasper County, IL, Johnson County, IL, Lawrence County, IL, Richland County, IL, Saline County, IL, Wabash County, IL, Wayne County, IL, White County, IL, Williamson County, IL, Boone County, IN, Brown County, IN, Carroll County, IN, Cass County, IN, Clay County, IN, Clinton County, IN, Daviess County, IN, Fountain County, IN, Gibson County, IN, Grant County, IN, Greene County, IN, Hamilton County, IN, Hancock County, IN, Hendricks County, IN, Howard County, IN, Johnson County, IN, Knox County, IN, Madison County, IN, Marion County, IN, Martin County, IN, Miami County, IN, Monroe County, IN, Montgomery County, IN, Morgan County, IN, Owen County, IN, Parke County, IN, Pike County, IN, Posey County, IN, Putnam County, IN, Sullivan County, IN, Tippecanoe County, IN, Tipton County, IN, Vanderburgh County, IN, Vigo County, IN, Wabash County, IN, White County, IN

The radar

The Evansville,IN radar (KVWX), 78 km from the middle of the area, began a volume at 14:05 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

Lincoln, IL (KILX), launched 12:00Z, 2.1 hours before the alert went out and 146 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1603 J/kg
Mixed-layer CIN: -50 J/kg
Mixed-layer LCL: 678 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 91 m²/s²
0-3 km storm-relative helicity: 108 m²/s²
Significant tornado parameter: 0.6
Supercell composite: 4.4

Open this sounding in Storm Lab

The text

As transmitted.

057 
ACUS11 KWNS 261405
SWOMCD
SPC MCD 261405 
INZ000-KYZ000-ILZ000-261530-

MESOSCALE DISCUSSION 0738
NWS STORM PREDICTION CENTER NORMAN OK
0905 AM CDT THU MAY 26 2016

AREAS AFFECTED...SERN ILLINOIS INTO WRN INDIANA...AND ADJACENT
PORTIONS OF THE LWR OHIO VALLEY

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 261405Z - 261530Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...THE NEED FOR A WATCH IS NOT ANTICIPATED...BUT TRENDS WILL
CONTINUE TO BE MONITORED.

DISCUSSION...THE LATEST RAPID REFRESH OUTPUT SUGGESTS THAT A
MODESTLY MOIST BOUNDARY LAYER ACROSS THE MIDDLE MISSISSIPPI INTO
LOWER OHIO VALLEYS REMAINS RATHER STRONGLY CAPPED BY WARM MID-LEVEL
TEMPERATURES.  HOWEVER...FORCING ALONG THE LEADING EDGE OF
CONSOLIDATED EASTWARD/SOUTHEASTWARD ADVANCING CONVECTIVE OUTFLOWS IS
STRONG ENOUGH TO OVERCOME THIS INHIBITION AND MAINTAIN VIGOROUS
CONVECTIVE DEVELOPMENT.

DESPITE THE PRESENCE OF STRONG THUNDERSTORM DEVELOPMENT...WESTERLY
AMBIENT DEEP LAYER MEAN FLOW ACROSS THIS REGION IS RATHER
MODEST...ON THE ORDER OF 20-30 KT.  AND GUIDANCE SUGGESTS THAT
ACTIVITY IS TENDING TO FORWARD PROPAGATE INTO A PROGRESSIVELY LESS
UNSTABLE ENVIRONMENT WITH EASTWARD EXTENT ACROSS THE LOWER OHIO
VALLEY. 

LONGER TERM SEVERE WEATHER POTENTIAL WITH THE ONGOING CONVECTIVE
SYSTEM SEEMS LIMITED.  HOWEVER...UNTIL CONVECTION BEGINS INGESTING
LESS UNSTABLE AIR /PERHAPS BY 15Z/...40+ KT SURFACE GUSTS AND
GENERALLY MARGINALLY SEVERE HAIL MAY PERSIST NEAR STRONGER ACTIVITY/

..KERR/HART.. 05/26/2016

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

ATTN...WFO...LMK...IWX...IND...PAH...LOT...ILX...

LAT...LON   37778965 38238867 38978824 39478747 40228728 41018719
            41078549 39808558 38118739 37338871 37668942 37778965

Nearby

Mesoscale Discussions in Indiana, 2016 Mesoscale Discussions in Illinois, 2016 Every mesoscale discussion in 2016

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.