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Critical fire weather conditions continue through this evening due to north winds and low humidity. Gradual warming trend for the rest of the week, with breezy north winds and low humidity expected again on Thursday.

Discussion

A portion of NorCal will still feel the lingering effects of the anonymously deep upper low near KLAS. NAEFS mean wind speed standardized anomalies show the SWrn portion of our CWA, (generally western portions of the southern Sacramento Valley, Solano Co, and western portion of the northern San Joaquin Valley) still under the effects of the unidirectional northerly flow through the morning hours. The LAMP guidance for SUU and VCB still indicate wind advisory criteria will be met this morning, in deference to the 925 mbs wind core moving through the area. As the upper low moves into the CO Rockies this afternoon and 5H heights recover over NorCal the winds will decrease.

A much weaker and progressive trough and cold front is forecast to bring another chance of some light rain/snow showers to our northern mountains tonight and Wed as it moves into the Pac NW and then inland. With most of the energy and available moisture with this trof passing north of our CWA, precip amounts are expected to be very light in our CWA.

As this progressive trof moves eastward and Pacific high pressure builds eastward into our forecast area, more northerly wind is expected again on Thu. Although not nearly as strong/intense as this most recent system, given the state of the fuel conditions in NorCal there will be some continued fire weather concerns, mainly in the Valley and lee-side of the coastal range.

Although temps will gradually recover in the short term, they will remain below normal through mid week. Max temps are forecast to return to normal by Fri.

Extended Discussion (Saturday through Tuesday)

Upper ridge axis over the Intermountain West Saturday as upstream Pacific frontal system approaches. Models suggest baroclinic zone weakens as it moves onshore and associated precipitation remains outside of the CWA. Upper ridging returns early next week.

High temperatures expected to be near to slightly below normal through the extended forecast period.