Area Forecast Discussion
Issued by NWS Sacramento, CA
Issued by NWS Sacramento, CA
461 FXUS66 KSTO 101930 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 1230 PM PDT Fri May 10 2024 .SYNOPSIS... The influence of high pressure will bring dry weather with widespread above normal temperatures through the weekend and well into next week, with Valley highs in the 90s and areas of Moderate Heat Risk. && .DISCUSSION... Current GOES-West satellite imagery shows abundant sunshine being observed across interior northern California on this Friday afternoon. Temperatures are currently trending appproximately 3 to 10 degrees warmer than this time yesterday afternoon, valid at 1230 PM PDT. Upper level ridging continues over the eastern Pacific and Pacific NW with troughing over the Great Basin. Dry conditions and warmer weather prevails over the next several days. Forecast highs are expected to be in the upper 80s to mid 90s in the Valley over the next few days, with 80s in the foothills and 60s to 80s in the mountains. Temperatures will be trending above the climatological normal for this time of year, resulting in areas of Moderate Heat Risk in the Valley each day. Sensitive groups and vulnerable populations should take the necessary precautions for the increasing temperatures. The National Blend of Models (NBM) shows chances for a shower or thunderstorm on Monday afternoon in the High Sierra south of Highway 50 (10 to 15 percent probability) associated with a trough. For today, chances for any shower or thunderstorm development have decreased (less than 10 percent probability) and look to be south of our area of coverage, however some cumulus cloud development is still expected over the Sierra. && .EXTENDED DISCUSSION (Tuesday THROUGH Friday)... Ensemble guidance and cluster analysis indicate the continued influence of high pressure over the extended forecast period, keeping temperatures warm and conditions dry. There is still some uncertainty with the strength of the upper level ridging though, and as a result there is a decent spread in high temperatures for mid to late next week. The National Blend of Models (NBM) even suggests a 25 to 55 percent probability of reaching 100 degrees in portions of the Sacramento Valley mid next week. Towards the end of next week or even into next weekend, guidance also suggests some troughing as a potential outcome with slightly cooler temperatures but details are uncertain at this time. && .AVIATION... VFR conditions prevail across interior NorCal through the forecast period with light northerly Valley winds, less than 12 kts. Breezy easterly winds expected over the Sierra and foothills, with occasional gusts to 20 kts. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$