Mesoscale Discussion 183

Issued

Feb 29, 2012, 12:41 PM EST (17:41 UTC)

Expired

Feb 29, 2012, 3:15 PM EST

In force

3 hr

Issued by

the Storm Prediction Center

The Cincinnati radar (KILN), 71 km from the middle of the area, began a volume at 17:42 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.

• Tornado Watch 49Feb 29, 1:40 PM EST

733 
ACUS11 KWNS 291741
SWOMCD
SPC MCD 291741 
OHZ000-KYZ000-INZ000-292015-

MESOSCALE DISCUSSION 0183
NWS STORM PREDICTION CENTER NORMAN OK
1141 AM CST WED FEB 29 2012

AREAS AFFECTED...CNTRL/SRN/WRN OH...SERN IND...NRN KY

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 291741Z - 292015Z

CNTRL/SRN/WRN OH...SERN IND...AND NRN KY WILL BE MONITORED THROUGH
THE AFTERNOON HOURS FOR THE POSSIBLE ISSUANCE OF A WW. ONGOING
TORNADO WATCH 47 ACROSS SRN OH AND NRN KY WILL BE ALLOWED TO EXPIRE
ON SCHEDULE AT 18Z...THOUGH AN ADDITIONAL WW MAY BE NEEDED ACROSS
THIS AREA LATER THIS AFTERNOON.

STRATIFORM RAIN AND EMBEDDED CONVECTIVE ELEMENTS ACROSS SRN OH AND
NRN KY CONTINUE NORTH OF A PREFRONTAL SQUALL LINE LOCATED ACROSS
KY/TN. BOUNDARY LAYER STABILIZATION OWING TO THE PRECIPITATION WILL
CONTINUE TO MITIGATE THE SVR THREAT DURING THE NEXT COUPLE OF HOURS
ACROSS WW47. WHILE SFC TEMPERATURES MAY STRUGGLE TO SUBSTANTIALLY
INCREASE IF THIS ACTIVITY IS SLOW TO CLEAR...RELATIVELY MORE RICH
LOW-LEVEL MOISTURE /SFC DEWPOINTS IN THE UPPER 50S TO LOWER 60S/
ALONG THE OH RIVER WILL SUPPORT MARGINAL DESTABILIZATION DESPITE THE
ONGOING PRECIP. VIS SATELLITE IMAGES INDICATE MORE ABUNDANT POCKETS
OF INSOLATION NORTH OF THE ONGOING ACTIVITY INTO PARTS OF
CNTRL/W-CNTRL OH AND ERN IND...WHERE STEEPENING LOW-LEVEL LAPSE
RATES JUXTAPOSED WITH SFC DEWPOINTS IN THE MIDDLE 50S ARE
CONTRIBUTING TO MARGINAL DESTABILIZATION. MODIFICATIONS TO THE 12Z
WILMINGTON OH RAOB TO ACCOUNT FOR CURRENT SFC TEMPS/DEWPOINTS
INDICATE SBCAPE ALREADY NEARING 500 J/KG FROM APPROXIMATELY
COLUMBUS-DAYTON-RICHMOND...WHERE ADDITIONAL DESTABILIZATION WILL
OCCUR AS BOUNDARY-LAYER MOISTURE ADVECTION CONTINUES IN COMBINATION
WITH ADDITIONAL INSOLATION.

DESPITE WEAK SFC CONVERGENCE ALONG THE FRONT IN WRN IND...IT MAY BE
SUFFICIENT FOR THE DEVELOPMENT OF THUNDERSTORMS AFTER
1900Z...ESPECIALLY OWING TO THE INCREASING INSTABILITY AND
STRENGTHENING DCVA IN CONJUNCTION WITH AN APPROACHING MID-LEVEL
IMPULSE SWINGING AROUND AN UPPER-MIDWEST CLOSED LOW. STRONG
LOW-LEVEL AND DEEP-LAYER VERTICAL SHEAR IS IN PLACE...WITH
WILMINGTON OH VWP DATA INDICATING A SFC-3-KM BULK SHEAR MAGNITUDE
AROUND 55 KT. IF CONVECTION CAN DEEPEN SUFFICIENTLY...FAST-MOVING
LINE SEGMENTS AND POSSIBLY SUPERCELLS MAY ENSUE...WITH DMGG WIND
GUSTS THE PRIMARY CONCERN RESULTING FROM MAINLY UNIDIRECTIONAL FLOW
THROUGH THE CLOUD LAYER. HOWEVER...THE STRENGTH OF THE LOW-LEVEL
SHEAR AND SOME SLIGHT CURVATURE OF THE HODOGRAPH JUST ABOVE THE
SURFACE MAY SUPPORT THE THREAT FOR A TORNADO OR TWO...PARTICULARLY
FROM CNTRL OH SWD TO NRN KY INVOF THE RICHER LOW-LEVEL MOISTURE. AS
SUCH...THE AREA WILL BE MONITORED FOR THE POSSIBLE ISSUANCE OF A WW
LATER THIS AFTERNOON.

..COHEN.. 02/29/2012

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

ATTN...WFO...RLX...CLE...ILN...LMK...IWX...IND...

LAT...LON   40688234 39348237 38558295 38578489 39838501 40968394
            41018300 40688234

Mesoscale Discussions in Ohio, 2012Mesoscale Discussions in Kentucky, 2012Mesoscale Discussions in Indiana, 2012Every mesoscale discussion in 2012

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.