MESOSCALE PRECIPITATION DISCUSSION 0407
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
125 PM EDT THU JUL 05 2018

AREAS AFFECTED...NERN/E-CTRL IL...INDIANA...WRN OH

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 051724Z - 052230Z

SUMMARY...THUNDERSTORMS WERE CONTINUING TO DEVELOP IN AN ARC FROM
ILLINOIS...THROUGH INDIANA...AND INTO OHIO. THESE STORMS MAY
REPEATEDLY MOVE OVER CERTAIN AREAS AND COULD POSE A RISK OF FLASH
FLOODING. RAIN RATES MAY REACH 2 IN/HR IN SOME AREAS.

DISCUSSION...REGIONAL RADARS SHOWED A FORWARD PROPAGATING SQUALL
LINE JUST ARRIVING IN THE I-69 CORRIDOR IN CENTRAL INDIANA AROUND
17Z...WITH A TRAILING BAND OF CONVECTION INCREASINGLY
CONSOLIDATING ON A ESE-WNW AXIS FROM NEAR IND... TO NEAR DNV... TO
NEAR PNT. ADDITIONAL CONVECTION WAS ALSO DEVELOPING TO THE ENE
INTO PORTIONS OF WRN OHIO. THE INCREASE IN CONVECTIVE COVERAGE AND
ORGANIZATION WAS TAKING PLACE JUST AHEAD OF A WEAK SHORTWAVE NEAR
THE WI-IL BORDER...AND MAY CONTINUE FOR SEVERAL HOURS INTO THE
AFTERNOON. OTHER THAN THE AREA IMMEDIATELY BEHIND THE SQUALL LINE
(WHERE A COLD POOL HAS BEEN DEVELOPING WITH A MESO-HIGH)...THE
ENVIRONMENT THAT THE CONVECTION IS DEVELOPING IN IS QUITE UNSTABLE
WITH MLCAPE VALUES AROUND 2000-3000 J/KG...CERTAINLY SUPPORTIVE OF
CONTINUED STORM ORGANIZATION. BROAD 15 KNOT LOW-LEVEL (925-850MB)
INFLOW SHOWN ON REGIONAL VWPS UPSTREAM OF CURRENT CONVECTION (KIND
AND KILX) SHOULD ALSO SUSTAIN CONVECTION NEAR THE CURRENT AXIS OF
DEVELOPMENT FROM ILLINOIS INTO INDIANA...AND A VEERING OF THE
LOW-LEVEL FLOW MAY PROMOTE MORE TRAINING OVER THE NEXT SEVERAL
HOURS.

GIVEN THE AVAILABLE INSTABILITY AND MOISTURE (PWS AROUND 2
INCHES)...ANY STORMS SHOULD BE CAPABLE OF HEAVY RAIN RATES AROUND
2 IN/HR...PARTICULARLY IF TRAINING STORM MOTIONS CAN BE REALIZED.
THIS MAY SUPPORT A THREAT OF FLASH FLOODING INTO THE AFTERNOON
HOURS...ESPECIALLY IF TRAINING BANDS FAVORABLY ALIGN WITH
URBANIZED AREAS.

LAMERS

ATTN...WFO...CLE...DVN...ILN...ILX...IND...IWX...LMK...LOT...

ATTN...RFC...NCRFC...OHRFC...

LAT...LON   41948761 41038681 40618559 41068429 41018305
            39838368 38868389 38748524 39338686 40158878
            41098976 41948934