704
AWUS01 KWNH 171648
FFGMPD
NYZ000-PAZ000-WVZ000-OHZ000-172200-

Mesoscale Precipitation Discussion 0639
NWS Weather Prediction Center College Park MD
1247 PM EDT Wed Jul 17 2024

Areas affected...Eastern OH...Western PA

Concerning...Heavy rainfall...Flash flooding possible

Valid 171646Z - 172200Z

Summary...Showers and storms increasing in coverage and intensity
through the early to mid afternoon hours may train over some
areas, leading to multiple rounds of heavy rainfall that may lead
to some instances of flooding though 6 pm local time with rainfall
rates of 1-2 inches per hour with the strongest storms.

Discussion...Regional Doppler radars are indicating a rapid
increase in convection along and ahead of a cold front from
eastern Ohio into eastern and central Pennsylvania.  The latest
SPC mesoanalysis depicts PWs rising into the 1.75 to 2.00 inch
range, with nearly uni-directional flow from the WSW in the
300-850 mb layer.  In tandem with mixed layer CAPE on the order of
750-1250 J/kg and lower 70s F surface dewpoints, the overall
environment is becoming more conducive for storms with high
rainfall rates.

The latest CAM guidance has a reasonable overall depiction of the
ongoing convection evolution across the region, including the most
recent HRRR runs.  The guidance suggests the potential for
scattered 2-3 inch maxima, with much of this falling within a two
hour time period for any given location.  A few instances of
flooding will be possible through this afternoon.

Hamrick

...Please see www.wpc.ncep.noaa.gov for graphic product...

ATTN...WFO...BGM...BUF...CLE...CTP...ILN...PBZ...

ATTN...RFC...MARFC...NERFC...OHRFC...NWC...

LAT...LON   42097783 41797719 41157744 40417870 39957980
            39808098 39938211 40088261 40488269 40738252
            41008207 41138158 41358083 41528018 41737971
            41927920 42077868