Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
330 AM EDT Mon Mar 16 2026
Day 3
Valid 12Z Wed Mar 18 2026 - 12Z Thu Mar 19 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
WASHINGTON STATE...

Occluded low over the Gulf of Alaska a strong mid-level ridge
positioned across the Southwest U.S. will lead to a continued
transport of modest IVT into WA state for the D3 period. AR
dominated pattern will enhance rainfall prospects for the northern
half of WA leading to cumulative rainfall totals breaching 4" in
spots within the Northern Cascades, Olympics, and adjacent coastal
areas of northwest WA. Real concern is the growing hydrologic
factors with river flooding coupled with moderate rainfall posing a
problem for areas around the main rivers and tributaries for the
aforementioned areas. Flash flood threat remains low due to the
rates anticipated with the rainfall as hourly rainfall will remain
<0.5"/hr for a majority of Wednesday. However, the coupling of the
previous days rain and the already saturated soils will likely lead
to some hydro concerns mid-week, so maintained the previous MRGL
risk inherited with only some minor tweaks at the southwest edge of
the risk.


Kleebauer

Day 3 threat area: www.wpc.ncep.noaa.gov/qpf/99epoints.txt