296
AWUS01 KWNH 061836
FFGMPD
MDZ000-VAZ000-NCZ000-WVZ000-TNZ000-070030-

Mesoscale Precipitation Discussion 0231
NWS Weather Prediction Center College Park MD
235 PM EDT Mon May 06 2024

Areas affected...Western Virginia and North Carolina

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

Valid 061835Z - 070030Z

SUMMARY...Thunderstorms associated with an advancing upper level
shortwave are developing in a very unstable and moisture-rich
environment across portions of the Mid-Atlantic. Flash flooding
will be possible where multiple rounds of storms impact
flood-sensitive areas.

DISCUSSION...An area of thunderstorms associated with an upper
level shortwave trough is moving east into the Mid-Atlantic this
afternoon. The storms are moving into an environment characterized
by PWATs up to 1.75 inches across eastern Virginia and North
Carolina, and SBCAPE values as high as 2,500 J/kg based on SPC
Mesoanalysis. The storms that have formed so far have produced
local rainfall rates up to 2.5 inches per hour. Some clearing over
central Virginia has allowed for instability to rapidly increase
in the moisture rich environment. More isolated thunderstorms have
developed ahead of the main area of storms. These storms have been
slow-moving, and locally increase the potential for flash flooding
as additional storms follow behind the ones ahead of the line.

As the storms approach a boundary over northern Virginia in the
next few hours, they are expected to develop into an east-west
oriented line, likely over central Virginia south of the boundary.
CAMs are in reasonable agreement as to this new line of storms
developing. As additional storms run into the boundary over
Northern Virginia, training storms will become more likely. While
this area has been relatively dry compared to areas further north
towards DC and its Virginia suburbs, rates up to 2.5 inches per
hour could cause localized flash flooding into this evening as the
heavy rainfall overwhelms local watersheds.

Wegman

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

ATTN...WFO...AKQ...GSP...LWX...MRX...RAH...RLX...RNK...

ATTN...RFC...LMRFC...MARFC...OHRFC...SERFC...NWC...

LAT...LON   38897915 38857828 38837795 38757759 38597709
            37937688 37267752 36407860 36157954 35368182
            36478166 37098193 37568192 38438066