textproduct: Reno

KEY MESSAGES

* Isolated light rain and mountain snow showers across far northeast CA today with dry conditions elsewhere.

* Dry and mild conditions continue across the region through Thursday, with a gradual cooling trend beginning Friday.

* An unsettled pattern will bring increasing chances for widespread precipitation and cooler temperatures late week into the weekend.

DISCUSSION

A weak shortwave trough will pass by to our north today, leading to sunny and mostly dry conditions. There will be a 15-20% chance of light showers in the same areas as yesterday - over the Warner Mountains and far northern Washoe County. Temperatures will be mild for late October, with valley highs reaching the upper 50s to upper 60s, and Sierra communities seeing highs in the 50s.

Wednesday and Thursday, continued dry and sunny conditions are expected under the influence of high pressure. Highs in the upper 50s to mid-60s for valleys and 50s for the Sierra. Winds will remain light. Clouds will begin to increase across the region as an embedded shortwave trough swings in off the West Coast around a larger low pressure system off the coast of Washington.

Precipitation chances start to increase (10-30%) across the Sierra from Tahoe southward as early as Thursday night as the leading edge of moisture works its way into the region. Snow levels are expected to be around 6000-7000 feet. Precipitation chances continue on Friday for the Sierra, with similar snow levels. Precip timing and amounts still need to be honed in due to model uncertainty, but as it stands right now, it's looking to be on the lighter side.

The main period of unsettled weather is expected this weekend (Saturday and Sunday). The deepening Pac NW trough will bring widespread chances for rain and snow across the entire forecast area. Model guidance indicates increasing probabilities for precipitation (40-50%), with snow expected in the Sierra and surrounding foothills. Snow levels are expected to drop to around 5000-6000 feet, potentially lower at times, especially Saturday night. QPF amounts remain uncertain, as models show a large spread in QPF. But for example, the NBM has a 24 hour QPF spread of 0.00"-0.45" (25th vs 75th percentile) along the Sierra from Tahoe southward ending Sunday at 4PM. So, still lots to iron out between then and now.

Lastly, temperatures will be significantly cooler this weekend, with highs in the 50s in the valleys, and 40s in the Sierra. Overnight lows will be cold, in the teens and 20s for the Sierra, and 20s and 30s for the valleys.

-Justin

AVIATION

VFR expected today through tomorrow. Mostly sunny skies and breezy afternoon winds gusting up to 25kt prevail today, with FL100 winds out of the W-SW topping out around 30kt this afternoon.

-Justin

REV Watches/Warnings/Advisories

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