Area Forecast Discussion
Issued by NWS Sacramento, CA
Issued by NWS Sacramento, CA
118 FXUS66 KSTO 200830 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 130 AM PDT Mon May 20 2024 .SYNOPSIS... Warm and dry weather expected for the next week with temperatures close to average. Occasional breezy north winds in the Central Valley this week. && .DISCUSSION... Clear skies cover the region as cloudiness associated with the upper trough has shifted south into central California. Northerly surface pressure has continued to tighten across far northern California overnight (MFR-RDD is around 10 mbs) and the RDD-SAC gradient has reversed in the past couple of hours and is now around 1 mb. Northerly wind gusts of 15-30 mph have developed over the northern Sacramento Valley early this morning, but onshore gradient lingers further south with gusts around 15-20 mph extending from the Delta into the northern San Joaquin Valley. North winds will spread southward through the Sacramento Valley this morning as the upper flow behind the departing trough becomes aligned with the tightening surface gradient. Gusts of 25-35 mph are expected, and combined with minimum humidity in the upper single digits and teens will lead to local enhanced fire weather conditions where fine fuels (grasses) have cured in the valley and lower foothills. Winds are expected to decrease by this evening. Enough moisture and instability may remain on the backside of the trough for an isolated shower or thunderstorm to pop along the Sierra crest south of Tahoe late today, but northwesterly steering flow will likely keep any that develop right along the crest before moving east. The trough will weaken a bit on Tuesday allowing for minor warming and lighter winds across the region. Another system is forecast to move from the PacNW into the northern Rockies later on Wednesday into Thursday bringing some more minor cooling along with another round of breezy north winds to the Central Valley. && .EXTENDED DISCUSSION (Friday THROUGH Monday)... Clusters and ensembles indicate the likelihood of a weak trough lingering over the region through the weekend with northwest flow aloft favoring dry weather with temperatures at or a little below average. By Memorial Day, signs point toward amplifying ridging over the western US leading to the beginning of a warming trend next week. && .AVIATION... VFR conditions next 24 hours. Areas of northerly surface wind gusts 20-30 kts in the Central Valley, strongest 16Z thru about 02Z Tuesday. && .STO WATCHES/WARNINGS/ADVISORIES...None. && $$