Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
311 AM EST Tue Feb 10 2026
Day 1
Valid 12Z Tue Feb 10 2026 - 12Z Wed Feb 11 2026

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

...Transverse Range of Southern California...
The 10/00Z suite of global and ensemble guidance still suggests
that a modest atmospheric river associated with a Pacific cold
front advancing inland across central and southern CA later
tonight/early Wednesday morning. The latest runs of the GFS/ECMWF
still suggest rather modest IVT magnitudes with the event. Any
concern for excessive rainfall arise during a fairly small window
when the moisture plume becomes oriented normal to the axis of the
Transverse Range. One to 2 inches of rainfall shown by the
GFS/ECMWF could be closer to 3 inches in spots where orographic
upslope contributes additional lift. The signals of that happening
for a long enough duration for problems to develop remain low...so
held off on introducing a Marginal Risk area again. Even so...an
upgrade may still be needed especially given some of the runoff
sensitivities with burn scars and the sloped terrain.

Bann

Day 1 threat area: www.wpc.ncep.noaa.gov/qpf/94epoints.txt