textproduct: Reno

KEY MESSAGES

* Gusty winds will present minor impacts to fire, recreation, and travel today and Tuesday.

* Rain, mountain snow, and thunderstorms expected mid to late week. Snow may impact travel across the Sierra in Mono County.

* Much cooler temperatures with chilly nighttime lows expected late this week and weekend.

DISCUSSION

Low pressure off the California coast will encourage S/SW gusts of 25-35 mph this afternoon across NE California, E Sierra valleys, and far W Nevada. Ridgetop winds remain elevated through Tuesday morning with gusts of 50-70 mph at times. Expect lakes (most notably Lake Tahoe) to be a bit more choppy in these areas, with impacts to air/ground travel. Brief near-critical fire weather conditions are also anticipated this afternoon (more details below). Otherwise, warm and dry weather continues for at least one more day as temperatures climb into the mid-60s (Sierra locations) and mid-70s (lower elevations) this afternoon.

After today, wind impacts shift to S Mono, Mineral, and E Churchill counties where S/SE gusts reach 30-40 mph Tuesday and Wednesday afternoons. Crowley, Mono, and Walker lakes will likely become choppy on these days, with gusty crosswinds along stretches of US-6, US-95, and US-50.

A Pacific storm remains on track to deliver periods of rain and mountain snow, thunderstorms, and much cooler weather from mid to late week. Rain may begin as early as Tuesday afternoon (10-20% chance), focusing on NE California, the E Sierra, and far W Nevada -- including the Tahoe Basin, Greater Reno area, and Mammoth. Wednesday and Thursday are still favored as the wettest days of the week when chances of rain and mountain snow increase to 60-90% areawide. Strong synoptic lift overspreading the region may support thunderstorms as early as Wednesday morning, with a broad swath of 10-30% odds Wednesday afternoon. Additional thunderstorms are possible Thursday afternoon, but uncertainty in the low's positions lends to lower confidence. Rain and snow showers linger into Friday morning before drier air moves in behind a cold frontal passage.

This week's storm continues to trend wetter as most areas have at least a 70% chance of receiving 0.25" of rain (or liquid equivalent) through Friday. Likewise, the probability of localized totals of 1" or more has increased to 30-50%, favoring the E Sierra and NE California. It's worth noting that rainfall may under/overperform in some areas due to locally heavier rain from showers and thunderstorms -- which is likely needed to achieve the higher end totals of 1" or more discussed previously. Heaviest snowfall continues to favor the Sierra crest of Mono County and the White Mountains where there is high probability of 4"+ of snowfall between Wednesday and Friday morning. This includes higher mountain passes in Mono County such as Tioga and Sonora, so be prepared for travel disruptions along these routes.

Temperatures will become much cooler after today, with daytime highs in the 40s and 50s by the end of the week. Nights will also become chilly, especially Friday night as temperatures fall into the 20s and 30s (teens for cold prone Sierra valleys). Gusty NE winds are also possible along and west of the Sierra crest Friday into Saturday, making it feel even colder in higher backcountry areas.

-Salas

AVIATION

S/SW surface gusts will increase to around 25 kts after 17-18Z at KTRK and KTVL, and after 19Z for KRNO and all other terminals. Meanwhile, S-SW FL100 winds of 25-30 kts will increase to 35 kts early Tuesday morning. These winds will pose minor LLWS and mountain wave turbulence impacts until 12Z Tuesday when winds become light.

Otherwise, widespread VFR conditions prevail through Tuesday morning before chances of rain and mountain snow increase from Tuesday afternoon through Thursday. Thunderstorm chances also increase Wednesday afternoon.

-Salas

FIRE WEATHER

Winds will increase this afternoon ahead of a Pacific storm approaching the West. South-Southwest wind gusts will waver around 30 mph with localized gusts up to 40 mph for the Sierra north of Highways 50/88 into Plumas-Lassen and northern Washoe County, and the Reno-Carson-Douglas-Storey area. These winds along with recent warm and dry conditions will lead to an elevated wildfire threat and may produce localized critical conditions.

By Tuesday night into Wednesday, the Pacific storm is projected to bring widespread wetting rainfall and high elevation snow. Most areas have a 70% chance or higher of receiving at least 0.25" of liquid between Wednesday and Thursday. For the eastern Sierra, plan on accumulating snow (3-8 inches) above 7500-8000 feet by Friday morning. Thunderstorm chances also increase Wednesday morning and afternoon, perhaps returning Thursday afternoon.

-Lindaman/Salas

REV Watches/Warnings/Advisories

NV...None. CA...None.