589
FXUS66 KSTO 271859
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
1059 AM PST Sat Dec 27 2025

For additional details on weather and expected impacts over the
next 7 days, please visit weather.gov/sto/briefing.


.KEY MESSAGES...

 - Next chance of rain and mountain snow looks to be New Years
   Day. Confidence not very high right now with intensity but
   worst case sceneario would be much less impactful then recent
   storms.

 - Fog/low clouds possible in the Valley/foothills once again this
   week leading up to the next weather system.


&&

.DISCUSSION...

...Tonight through Wednesday...
Norhterly winds over the area as storm system which brought us all
our winds/rain and snow moves out of the area. High confidence of
a ridge that build into the area starting tomorrow...likely
peaking in strength Tuesday with axis of the ridge shifting to our
east by Wednesday. This pattern looks very simliliar to earlier
this winter when we had Tule fog in the valley. Short range models
not hitting the fog/low clouds very high with probabilities
tonight which may be from at least some dry northerly surface
winds across the valley. As the ridge strengthens early next week
would expect valley fog and low clouds to occur again. This will
likely keep temperatures lower again in the valley with milder
temperatures in the foothills.

...New Years Day and Friday...
Interesting pattern setting up for this period with fairly big
difference in solutions. Cluster analysis showing most likely
pattern being a moderately deep trough setting up over the west
coast. Strongest solutions are the EC Ensemble solution with the
GFS right now much drier. Both models showing the main moisture
source for this trough to come from the southwest U.S. with really
not a tropical AR type moisture fetch. With the wetter ECS
solution...this system looks to NOT be nearly as impactful as the
last weeks storms. Right now, like the NBM solution of blending
the 2 GEFS/ECS solutions showing rain a good shot (50-80%) across
the valley New Years Eve day with the ECS wetter. Again, at worst
looks like mainly a low impact system. At this time, snow levels
look to be around 5000 feet with NBM probabilities maxing in the
4" range. Check back for updates with this system as it gets
closer. WMR
&&


.AVIATION...

Some lingering MVFR/IFR ceilings behind the passage of the storm
system today, then returning to general VFR conditions after
22Z-00Z. Surface winds out of the north around 5 to 12 kts with
gusts to 15-20 kts in the Valley, with northeast to east flow in
the foothills and mountains at times. Patchy MVFR/IFR/LIFR
conditions between 08Z-19Z Sunday in BR/FG at TAF sites from
Sacramento southward.

&&

.STO WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$