FXUS65 KREV 202102 AFDREV Area Forecast Discussion National Weather Service Reno NV 202 PM PDT Sun Sep 20 2026 .KEY MESSAGES... * Dry and mild conditions persist for the rest of today. * Precipitation potential returns Monday, especially for Mineral County and the eastern Sierra. * Plan on increased winds by Thursday and a return of precipitation chances by Friday. && .DISCUSSION... The latest RAP analysis of the upper air pattern shows the CWA underneath an upper ridge with an upper low off the CA coast this afternoon. Going through the rest of the day, models show the Pacific low progressing east toward CA and beginning to push the ridge eastward. Current satellite imagery shows partly to mostly cloudy skies across the region, which is expected to continue going into the night. The model consensus looks to favor dry conditions through the rest of the day. Overnight temperatures are forecast to be slightly higher than last night's with the increased cloud cover. Low temperatures in the valleys are forecast to be in the 50s with Sierra communities in the 40s. Model guidance then projects the western low moving across central CA tomorrow before opening into a trough passing through NV on Tuesday. With the projected track of this feature going through the southern portions of the CWA, the latest NBM guidance is now giving Mineral County and the eastern Sierra a ~20-40% chance for showers on Monday afternoon and evening. The latest RRFS continues to show some isolated shower chances (10-15% chance) reaching across the Tahoe region and into Lassen County, but not the best confidence yet with these chances as the HRRR stays dry in this portion of the area. QPF projections still are ranging up to around a few tenths of an inch at the highest Sierra elevations. Some rumbles of thunder could occur within showers on Monday, but chances are still on the low side for now (<10%). Elsewhere, dry conditions will persist tomorrow. Precipitation chances taper off to the east around midnight, leaving dry conditions to follow on Tuesday as temperatures continue a slight warming trend. For Wednesday, more dry weather is expected with daytime high temperatures climbing to the middle to upper 80s range in the W NV valleys and the lower to upper 70s range in Sierra communities. While similar temperatures are in the forecast for Thursday, forecast ensembles show a trough moving into the PacNW by latter half of the day. This feature will allow for winds to increase a bit on Thursday and Friday (50-75% NBM probability of 30+ mph winds). Precipitation chances look to return on Friday with a potential cold front passage, but mostly for areas along the OR border which currently has a 15% chance for showers. If models begin to show the aforementioned trough moving more southward, the precipitation coverage may also spread more south in the region. Will be monitoring how models deal with this trough going forward. Otherwise, cooler temperatures are expected going into the weekend with dry conditions favored. -078 && .AVIATION... VFR conditions are expected at all TAF sites today and tonight with partly to mostly cloudy skies within the region. Winds will remain relatively light with afternoon gusts up to around 15 kts. Forecast models show winds at the Sierra crest gusting up to around 20 kts between 06-12Z Monday which may result in minor mountain wave turbulence concerns along and west of the Sierra. Precipitation chances (20-40%) return to Mineral County and the eastern Sierra between 18Z Monday and 06Z Tuesday, with a 10-15% chance for isolated showers across Tahoe and into NE CA during the same time. -078 && .REV Watches/Warnings/Advisories... NV...None. CA...None. && $$