Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
300 PM EST Sat Nov 15 2025

Valid 00Z Sun Nov 16 2025 - 00Z Tue Nov 18 2025

...Additional heavy rainfall likely with dangerous flooding and debris
flows possible for parts of southern California in this evening followed 
by a second round of moisture into northern and central California Sunday 
night into Monday...

...Well above-normal to record-breaking warmth across Texas into early
next week...

...Wintry mix across northern New York and interior New England, with
several inches of snow in the higher elevations tonight into Sunday...

A vigorous and slow-moving cyclone is currently bringing a robust surge of
subtropical moisture with strong onshore winds and the heaviest rainfall
into the southern half of California. The Weather Prediction Center (WPC)
is maintaining a Moderate Risk (Level 3 of 4) for excessive rainfall, the
second-highest category, centered over coastal southern California.
Additional rainfall totals of 2 to 3 inches can be expected, pushing storm
totals to over 6 inches especially along the Transverse Ranges.  Numerous
flash floods and debris flows will likely to impact southern to central
California into this evening, especially for burn scar and other
vulnerable areas in Los Angeles, Santa Barbara, and Ventura counties.
Meanwhile, the eastern edge of the heavy rain has reached southern Nevada
and is edging into western Arizona.

The main axis of heavy rainfall will slowly begin to shift east and
subside late tonight as the associated upper-level low weakens and tracks
inland, spreading widespread precipitation across the Great Basin, the
Southwest, and then the central and southern Rockies for the remainder of
the weekend. Meanwhile, a second surge of moisture associated with the
next Pacific frontal system will quickly reach central and northern
California beginning late Sunday and continuing into Monday. While
moisture values are expected to be less impressive, this next system will
bring additional rounds of precipitation with embedded thunderstorms,
renewing the threat for at least isolated flooding concerns. This second
system will also usher in colder air, driving snow levels down
significantly over the northern Sierra Nevada by Monday morning. Wet snow
will likely accumulate in earnest as the day progresses on Monday.
Meanwhile, scattered showers are expected to expand across the remainder
of California into western Nevada and central Arizona on Monday, along
with embedded thunderstorms especially ahead of the main cold front. Also
on Monday, wet snow is forecast to reach western Wyoming and portions of
the Colorado Rockies.

Further east, a large area of unseasonably warm air remains out ahead of a
strong cold front moving through the central and eastern U.S. As the cold
front advances quickly through these areas, a low pressure system is
forecast to develop and intensify, and track through the Great Lakes this
evening then through the Northeast on Sunday. Ahead of this system, a
wintry mix of snow, sleet, and freezing rain is developing over portions
of northern New York and New England this afternoon and will likely
continue into Sunday, with several inches of accumulating snow expected in
some of the higher elevations. As the system lifts out into the Canadian
Maritimes late Sunday, colder air from Canada in its wake will produce the
next chance of organized lake-effect snow showers downwind of the Great
Lakes. Meanwhile, blustery and colder conditions will expand across much
of the Great Lakes, Northeast, and into the Mid-Atlantic Sunday and
Monday. In contrast, well above-normal to record-breaking temperatures are
forecast to persist over the Southern Plains into early next week as the
trailing portion of the front begins to stall.


Kong/Pereira


Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php