![National Oceanic and Atmospheric Administration](/build/images/header/noaa.d87e0251.png)
![National Weather Service](/build/images/header/nws.4e6585d8.png)
![United States Department of Commerce](/build/images/header/doc.b38ba91a.png)
Area Forecast Discussion
Issued by NWS Sacramento, CA
Issued by NWS Sacramento, CA
057 FXUS66 KSTO 120749 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 1249 AM PDT Mon Aug 12 2024 .SYNOPSIS... Cooler temperatures and increasing humidity, with periods of breezy onshore winds this week. && .Discussion... With clear skies tonight, some have been able to see the Northern Lights, including some Alert California cameras up near Redding. Reports of sights of the lights have come in from as far south as Chico tonight. Some folks have seen portions of the Perseid meteor shower as well. Otherwise, the influence of the Delta Breeze can be felt in much of the southern Sacramento and northern San Joaquin Valleys tonight. Temperatures as of midnight were already in the low to mid 60s in the greater Sacramento metropolitan area, and are expected to get into the high 50s in areas later in the early morning. The current onshore flow will continue into tomorrow, moderating temperatures throughout the Valley. Highs in the area will range in the mid 80s to the low 90s in the Valley, with mid 60s to the mid 80s at higher elevations. This general temperature trend will continue through the end of the week, with slight variations throughout. However, conditions are expected to remain below climatological normal throughout the short term forecast period. && .EXTENDED DISCUSSION (Friday THROUGH Monday)... From late week into next weekend, cluster analysis is showing a high degree of confidence in the expected upper level pattern, with nearly all ensemble membership indicating a deepening trough off the coast of the Pacific Northwest. While a small portion (~15%) depicts a more progressive trough, the vast majority (~85%) indicates a building ridge over the south-central CONUS, blocking the trough in the Pacific Northwest vicinity into the weekend. While the expected orientation of the trough should allow for incremental gains in humidity recovery, deeper moisture advection for precipitation is not anticipated at this time. Rather, this pattern will look to allow a continuation of below normal temperatures from Friday into next weekend. Additionally, some breezier conditions will be possible as the trough deepens. Resultant current probabilities of wind gusts exceeding 25 mph outside of the Delta vicinity do increase to around 20% to 40% on Friday and Saturday. && .AVIATION... VFR conditions over interior NorCal next 24 hrs except isolated MVFR in HZ/FU possible at times in vicinity of fires. Southwesterly winds 10-15 kts with gusts 15-20 kts until 10z today, then again between 18z today and 10z Tuesday. Otherwise, wind below 12 kts. In and around the Delta, southwesterly surface winds sustained 15-20 kts with gusts 20-30 kts at times. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$