Version:  Current  |  Back 1  |  Back 2  |  Back 3  |  Back 4  |  Back 5  |
Hydrometeorological Discussion
National Weather Service / California Nevada RFC / Sacramento CA
105 PM PST Fri Feb 13 2026

...QUIET REST OF FRIDAY...
...PATTERN SHIFT TO COOLER AND WETTER LATE SATURDAY INTO NEXT WEEK...

.METEOROLOGICAL CONDITIONS (SHORT TERM: FRI PM - MON AM)...

Transitory upr ridge is currently overhead as the elongated system 
from yesterday is now moving through the 4-Corners region with the 
majority of the shower activity across the lower Colorado River 
basin. Otherwise...expect mainly dry conditions to wrap up the work 
week.

The weekend is still looking to be the transition to a wetter and 
cooler pattern as the initial disturbance moving from the Gulf of 
Alaska diving toward the south-southeast and slows its forward 
progress when reaching the coastal waters west of CA. This slowing 
has resulted in a delay in precip reaching coastal areas and then 
spreading inland...but models (sans the NAM) are starting to get a 
bit better handle on keeping much of Saturday dry except for some 
light shower activity across southwest OR and northwest CA ahead of 
the main precip band. Then into Sunday...precip increases along 
coastal sections primarily between Cape Mendocino and Point 
Conception before shifting inland across the Sierra...best northern 
and central sections. This is all as a second disturbance drops 
south along the west coast and kicks this initial system within 130W 
and angles it toward the CA coast. 

Freezing levels will drop through the event...starting out Saturday 
evening between 5500- and 7000-feet across northern CA and 6500- to 
9000-feet over central CA. Then through Sunday as the cooler airmass 
begins making its way over the region these will reach down to 4000- 
to 5500-feet across northern CA and 5000- to 7000-feet for central 
CA.


.METEOROLOGICAL CONDITIONS (LONG TERM: MON AM - THU AM)...

Monday morning, the surface low offshore will begin to push inland 
as the upper trough is nudged southeastward towards the CA coast by 
the next low dropping in from the Gulf of Alaska. This will spread 
precip inland and across central/southern coastal areas. There are 
some timing and positional differences between the GFS/ECMWF for 
Monday morning with the GFS more quickly progressing precip across 
the Transverse Range while the ECMWF is a bit slower. By the late 
afternoon, troughing from the next upper low will merge with the 
current system leaving CA/NV under a broad troughing pattern. This 
will allow showers to persist across the region with the coastal 
mountains and Sierra receiving the bulk of the precip. The offshore 
low will continue to descend offshore of the PacNW on Tuesday while 
the broader pattern shifts eastward. Expect continued precip 
throughout the day Tuesday, particularly along the central/srn CA 
coastal mountains and over the Sierra due to terrain effects. 
Wednesday, the system will push inland across CA and into NV with 
precip diminishing from west to east as it does so.

There is uncertainty in the precip for next week, mainly as some 
slight timing and positional differences on the placement/path of 
the low exist. There is decent confidence that the central coast 
mountains, Transverse Range, and Sierra will see the highest totals. 
Ensembles are divided now mainly on how much precip will fall along 
the coast north of the Golden Gate inland into Shasta. These 
disagreements are not slanted towards any one parent model, as in 
each QPF cluster is not dominated by one set of members. There is 
just a decent spread of values. 24 hour QPF spreads at Arcata for 
Tuesday/Wednesday are about 1.50".

The official forecast mainly went with the NBM, but blended in 
either the EC based west WRF or the GFS based west WRF over parts of 
the Transverse Range/srn Sierra depending on which was closer timing 
wise to the NBM. This was done in order to get in a little terrain 
enhancement that the broader models will not yet capture. QPF 12z 
Mon-12z Thurs: 3-7.50" Transverse/Sierra, 2.50-6" central coast 
mountains, 2-3.50" Shasta, 1.50-3" CA coastal areas and down the 
valleys. 

Freezing levels starting out 4-7 kft across the Sierra Monday 
morning lowering into Tuesday down to 3-5 kft. The entire region by 
that point should be below 7 kft. Lower freezing levels will push 
further to the south into Wednesday down to 2.5-3.5 kft north of I-
80 and 3-4.5 kft from I-80 to the southern Sierra. Most of the 
region, north of San Diego, should remain below 5.5 kft through the 
period.