775 
FOUS30 KWBC 140715
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
315 AM EDT Sat Mar 14 2026

Day 1
Valid 12Z Sat Mar 14 2026 - 12Z Sun Mar 15 2026

The probability of rainfall exceeding flash flood guidance is less
than 5 percent.

Kleebauer


Day 2
Valid 12Z Sun Mar 15 2026 - 12Z Mon Mar 16 2026

The probability of rainfall exceeding flash flood guidance is less
than 5 percent.

Kleebauer


Day 3
Valid 12Z Mon Mar 16 2026 - 12Z Tue Mar 17 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE NORTHEASTERN U.S...

Highly meridional setup expected this weekend, carrying into early
next week as a powerful cyclone materializes over the Midwest and
Great Lakes sending a strong cold front migrating west to east for
areas east of the Mississippi. Ahead of the front, a strong warm
air and deep moisture advection regime will couple to send PWATs
surging between 2-4 standard deviations above normal for areas east
of the Appalachians on Monday along with modest instability of
MUCAPE between 500-1000 J/kg over the Mid Atlantic and 200-400 J/kg
as far north as Central New England. Increased forcing at both the
surface with the approach of the cold front, as well as favorable
upper dynamics comprised of textbook diffluent flow aloft within
the RER of a 160kt jet will allow for quite the developing QLCS
structure off the lee-side of the Appalachians, pushing east into
the Piedmont, eventually to the coastal plain the end of the
period. 

Current QPF forecast is generally between 1-2" with a maxima
focused over Southern New England thanks to a multi-round setup of
heavy rain over that area. Setup will be relatively progressive,
but rates between 1-2"/hr at peak intensity should spur some issues
for flash flooding across the urban corridor along I-95. Add in
snow and ice melt across New England with the expected heavy rain
and the prospects for flash flooding will increase thanks to the
anomalous setup. Will be monitoring the trends in QPF closely as
the forecast is still outside the CAMs window. Convective nature of
the precipitation should provide some opportunity for local maxima
during the evolution on Monday and Monday night. Maintained general
continuity from the previous forecast of a broad MRGL encompassing
eastern PA up through Northern New England. Did make some minor
adjustments on the northern fringes as heaviest precip does look to
avoid some areas of far northern New England, including the
Champlain Valley up through northwest ME where guidance has
reflected a general min in the QPF distribution. Stay tuned over
the coming days as this setup has merit for a potential upgrade
across parts of the Northeastern CONUS. 

Kleebauer


Day 1 threat area: https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt
Day 2 threat area: https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt
Day 3 threat area: https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt