textproduct: Sacramento

KEY MESSAGES

- Dry weather, above normal temperatures, and periodically breezy winds through the weekend and into mid next week

- Potential shift toward active weather pattern late next week. Low confidence persists in the timing of potential precipitation

DISCUSSION

Today-Mid Week:

Warm and dry weather continues as high heights aloft persist over the next several days. Brief amplifying ridging into today gradually transitions toward west-southwest flow aloft Sunday into the early week ahead. With the building ridge today, gusty downslope northeast to east winds will remain strongest along the Sierra through the early morning hours, with gusts 25 to 35 mph through mid morning across the Sierra and adjacent foothills. Additionally, high temperatures do look to cool a few degrees in the northern Sacramento Valley, resulting in widespread 60s to 70s by the afternoon.

Afternoon high temperatures will remain 5-10 degrees above normal, with widespread Valley and foothills high temperatures in the low to mid 70s and widespread mountain high temperatures firmly into the 60s. With the transition toward ridging aloft then broad west-southwest flow, winds are expected to decrease throughout the day today, remaining generally light and onshore driven area wide across the rest of the weekend. While certainty remains middling, there is some potential that this brief transition to light onshore winds at the surface will yield increasing potential for Delta and Valley fog Sunday and Monday mornings. At this time, probabilities for visibility less than 1 mile sit around 40-60% each morning.

As deep troughing over the Gulf of Alaska begins to drift southward around the middle of the week, a secondary period of amplified ridging does look to build into the region late Tuesday- Wednesday. While notable uncertainty with this troughing feature persists, this would result in high temperatures briefly returning closer to 10 degrees above normal Tuesday and Wednesday afternoon highs in the mid 70s for the Valley and foothills and 60s to low 70s in the mountains. Additionally, this amplified ridging pattern would bring periods of gusty downslope east- northeast winds to the Sierra and foothills in the overnight and early morning hours once again.

Late Next Week:

Ensembles continue to indicate the potential for a shift toward an active weather pattern, with chances for heavy rain, heavy mountain snow and breezy winds. However, cluster guidance still indicates uncertainty regarding the position and timing of the upcoming trough. The anticipated southward progression of deep troughing over the Gulf of Alaska toward the California coast remains the largest piece of uncertainty at this time. With increasing ensemble consensus for a further southward trajectory of the initial ejecting shortwave Wednesday-Thursday, precipitation onset for interior NorCal is now favoring Friday into next weekend at the earliest. Regardless, the CPC 8-14 Day Outlook (Nov. 14-20) does continue to highlight a moderate risk for heavy rain and heavy mountain snow, as well as a slight chance for high winds which can be anticipated once the pattern does indeed shift. Be sure to stay up to date with the latest forecast information and check back for updates as we get closer.

AVIATION

VFR conditions are generally expected to prevail at TAF sites over the next 24 hours, although there is increasing potential for MVFR/IFR cigs in FG/BR at Valley and Delta sites after 09z Sunday. Winds will be lighter, remaining less than 12 kts at TAF sites, but still from a generally north to east direction. Breezy east-northeast winds continue along the Sierra and upper foothills gusting up to 20-30 kts, slowly decreasing after 12z but maintaining similar direction.

STO WATCHES/WARNINGS/ADVISORIES

None.