Mesoscale Precipitation Discussion 0460
NWS Weather Prediction Center College Park MD
222 PM EDT Mon Jun 16 2025

Areas affected...Southern Mid-Atlantic

Concerning...Heavy rainfall...Flash flooding likely

Valid 161822Z - 170022Z

SUMMARY...Heavy showers and thunderstorms will be developing and
expanding in coverage through the afternoon and into the evening
hours across much of the southern Mid-Atlantic region. Scattered
areas of flash flooding are likely, which will include concerns
for locally considerable urban flooding impacts.

DISCUSSION...Surface observations show a quasi-stationary front
draped once again across the southern Mid-Atlantic region and into
the central Appalachians, with the 18Z METARs showing the front
close to the VA/NC border and extending northwest up into eastern
WV. Strong diurnal heating along and south of the boundary has
allowed for the airmass across especially central and eastern NC
to become very unstable with MLCAPE values of 2000 to 3000 J/kg.

The low-level flow is very moist and rather convergent with PWs
over the eastern half of NC running upwards of 2.0 to 2.25 inches.
This coupled with additional surface heating over the next couple
of hours along with convergence in close proximity to the front
should favor the regional development and expansion of heavy
shower and thunderstorm activity over the next few hours which
will continue into the evening time frame.

Rainfall rates are expected to once again be very high, with rates
reaching as high as 2.5 inches/hour given the moist/unstable
environment. The convection should tend to be a combination of
slow-moving pulse and multi-cell convection, with some localized
concerns for cell-training possible.

The 12Z HREF supports some rainfall totals by 00Z (8pm EDT) of 3
to 5 inches, and some recent RRFS solutions support this as well.
Some areas of central and eastern NC saw rather heavy rainfall
totals over the last 24 hours and are relatively sensitive. This
combined with the additional rainfall, along with concerns for the
more sensitive urban areas, including the Raleigh-Durham
metropolitan area, suggests at least scattered areas of flash
flooding are likely. Locally considerable urban flooding impacts
will be possible going into the early evening hours.

Orrison

ATTN...WFO...AKQ...CAE...GSP...ILM...MHX...RAH...RNK...

ATTN...RFC...ALR...ORN...TIR...NWC...

LAT...LON   36997989 36737931 36537842 36427742 36457659
            36467588 35947551 35067581 34627769 34767938
            35138142 35418218 35828216 36198156 36518094
            36898035