725
FXUS66 KSTO 171934
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
1234 PM PDT Fri May 17 2024

.SYNOPSIS...
SEASONABLY WARM WEATHER CONTINUES THROUGH THE WEEKEND. MOSTLY
SUNNY AND DRY CONDITIONS PERSIST WITH PERIODICALLY BREEZY WINDS
ISOLATED SHOWER OR THUNDERSTORM CHANCES OVER THE HIGH SIERRA SOUTH
OF INTERSTATE 80 SATURDAY AFTERNOON.

&&

.DISCUSSION...
CURRENT GOES-WEST SATELLITE IMAGERY REVEALS THAT THE MARINE
STRATUS INTRUSION FROM THIS MORNING HAS SINCE LIFTED AND BURNED
OFF, AND NOW SUNNY SKIES ARE BEING OBSERVED ACROSS MOST OF
INTERIOR NORTHERN CALIFORNIA ON THIS FRIDAY AFTERNOON.
TEMPERATURES ARE CURRENTLY IN THE 70S TO low 80S IN THE VALLEY,
70S IN THE FOOTHILLS, AND 60S TO 70S IN THE MOUNTAINS, VALID AT
1230 PM PDT.

WARM AND DRY WEATHER CONTINUES AS SHORT WAVES TO THE NORTH
GRADUALLY WEAKEN THE UPPER LEVEL RIDGING. ISOLATED SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE ON SATURDAY AFTERNOON OVER THE
SIERRA CREST, MAINLY SOUTH OF INTERSTATE 80. THE NATIONAL BLEND OF
MODELS (NBM) SUGGESTS A 15-25% PROBABILITY OF THUNDERSTORM
DEVELOPMENT SATURDAY AFTERNOON THROUGH EARLY EVENING. ANY SHOWERS
OR STORMS THAT DEVELOP ARE EXPECTED TO QUICKLY DRIFT EAST OF THE
CREST AS A RESULT OF INCREASING SOUTHWESTERLY FLOW.

WITH RIDGING TO THE WEST AND TROUGHING TO THE EAST ON MONDAY,
LOCALLY BREEZY NORTHERLY WINDS RETURN TO INTERIOR NORCAL.
STRONGEST WINDS WILL IN THE SACRAMENTO VALLEY, MAINLY NORTH OF THE
SACRAMENTO METRO AREA, WHERE WIND GUSTS OF 20 TO 30 MPH ARE
POSSIBLE. RELATIVE HUMIDITY VALUES WILL ALSO BE LOWERING WITH
THE INCREASED NORTHERLY FLOW.

&&

.EXTENDED DISCUSSION (Tuesday THROUGH Friday)...
Ensemble guidance and cluster analysis indicate upper level
troughing over the Western US, with upper level ridging to the
west over the Pacific Ocean. This pattern will result in slight
cooling mid to late next week, however temperatures still remain
seasonably warm. Uncertainty remains in the potential for any
shower chances with this trough, and there is still a spread in
high temperatures over this timeframe. For now, the forecast
remains dry with highs returning to near normal by the end of the
week.

&&

.AVIATION...
VFR conditions across interior NorCal over the next 24 hours.
Surface winds generally at or below 12 kts. Increased
southwesterly flow after 21Z Saturday. 15-25% probability of
mountain showers or thunderstorms over the Sierra Crest south of
Interstate 80 after 18Z Saturday.

&&

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

&&

$$