Mesoscale Precipitation Discussion 0602
NWS Weather Prediction Center College Park MD
800 AM EDT Sun Jul 06 2025

Areas affected...E & SE North Carolina...Ext. E South Carolina...

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

Valid 061200Z - 061800Z

SUMMARY...T.S. Chantal

DISCUSSION...GOES-E Vis/IR animation shows a small but still
compact circulation to T.S. Chantal with a central dense overcast
(CDO) cluster of thunderstorms straddling the eastern NC/SC border
as it continues just north of northwest track.  This CDO is
expected to maintain given fairly solid vertical depth to the
cyclone with at least 4-6 more hours before asymmetries evolve due
to increased vertical shear profile.   Deep layer moisture over
2.5" and strong 30-40kt moisture convergence will continue to
support very efficient rainfall processes with 2-2.5"/hr rates
across much of the core.  Given slow translation speeds, spots of
3-5" are possible in/near the core. 

A solid banding feature continues to burst with similar cold
overshooting tops to -65C though those cores are a bit more
transient through the banding feature.  Strong confluent inflow
along the band in proximity to the Gulf Stream continues to
support strong back-building environment in the near term, as such
short-term training is possible through Onslow county.  However,
the dry slot rotating around the southern to southeastern quadrant
is starting to impinge on the band, mix and aid northward
propagation to reduce local duration of the band. So while
intense, the duration should be much less than areas near the CDO
and streaks of 1-3" are possible likely limiting flash flooding to
urban/poor drainage areas overwhelmed by the shear short-term
intensity of the banding features unless that back-building
short-term training is ideal but that would be very widely
scattered/isolated in nature.

Toward 16-18z, the solid warm air advection (WAA) across the
coastal plain of NC along with the wrapping dry slot will result
into increased elongation of the deeper layer circulation and
should result in a slowing of speed, but also a sharpening of a
northward trending convergence boundary near the NC/SC 'corner' of
Scotland/Marlboro counties.  This convergence band will be slow to
drift further west and the CDO should break down and expand
northward along this axis, increasing rainfall totals and
potential for 3-4" totals by 18z.

Hydrologically, naturally sandy soils that have been fairly dry
with relative soil moisture ratios below 40% and running in the
20-40th percentile for dryness, should uptake much of the rain
(with exception of impermeable urban settings) with hourly FFG
values of 2-3" and 3-4"/3hrs; only the most persistent/intense
rainfall areas are at risk of flash/rapid inundation flooding. 
Still, a few widely scattered incidents of flash flooding will
remain possible through the morning hours most likely near the
CDO.

Gallina

ATTN...WFO...CAE...ILM...MHX...RAH...

ATTN...RFC...ALR...NWC...

LAT...LON   35977784 35667662 35067578 34577621 34447684
            34427787 34247845 34087893 33977935 34257978
            34798004 35397977 35897896