Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus66 ksto 251122 

Area forecast discussion
National Weather Service Sacramento California
322 am PST Sat Feb 25 2017

flooding concerns continue as runoff from the recent rain
continues to work its way downstream adding stress to waterways. A
couple of weak but cold storms move through Saturday and Monday.
Extended period of dry weather starts the middle of next week.


closed upper low is currently situated off the California/Oregon
coast, with associated frontal system moving through the region.
Scattered showers have persisted across the northern portions of
our County Warning Area for much of the night, with mainly light precipitation
totals reported thus far. Snow levels have been low enough to
bring a bit of light snow to roads above 2000 ft or so.

The upper low will continue its path southward today, paralleling
the coast. While a few showers will continue mainly over the
higher elevations today, dynamics will remain far enough off the
cosat to keep most of the region dry. By tonight, skies should be
clearing again, allowing for another cold night across the region.
Some valley locations (particularly across the north) may reach
below freezing temperatures.

A second trough will move into the Pacific northwest Sunday,
bringing another round of showers to the region. Neither this
system nor the previous one tap into any meaningful moisture, so
precipitation won't be heavy. However, enough snow could fall over
the mountains that Sunday evening travel could be impacted. Snow
levels will remain low...mainly between 2000 and 3000 ft across
the region.

A few showers will persist into Monday under cyclonic flow aloft.
By Tuesday, drier northwest flow will take hold over the region.


extended discussion (wednesday through saturday)

Upper ridging over the West Coast will bring dry weather through
the extended period. Upper ridge weakens a bit towards the end of
next week as a Pacific storm system passes through the Pacific
northwest but any precipitation should remain north of the
forecast area. Daytime highs start out around normal on Wednesday
then warm through the end of the week especially in the northern
Sacramento Valley where light north winds and adiabatic warming
will push the Redding area up to around 70 degrees. Overall...daytime
temperatures at the end of next week should be up to between 5
and 10 degrees above normal.



Upper trough drops southward through norcal today. MVFR
occasional IFR ceilings northern Sacramento Valley and over
mountains next 24 hours. Mainly VFR conditions remainder Central
Valley. Occasional showers. Snow levels 2000 to 3000 feet. Mainly
northwest to northeast winds below 10 knots.


Sto watches/warnings/advisories...
Winter Weather Advisory from 10 am to 10 PM PST Sunday for
Shasta Lake area / northern Shasta County-West Slope northern
Sierra Nevada-western Plumas County/Lassen park.

Flash Flood Watch through late Thursday night for Carquinez
Strait and Delta.

National Weather Service Glossary of Abbreviations