textproduct: Reno

KEY MESSAGES

* Warmer and generally dry conditions are expected through Thursday with temperatures 5 to 10 degrees above average. * Strong winds are expected Thursday and Friday, especially in the Sierra and NE CA, leading to elevated fire weather concerns. * Temperatures about 5 to 10 degrees below normal and breezy winds return for the weekend.

DISCUSSION

The region is currently under the influence of a weak ridge, with recent satellite imagery showing generally clearing skies across the CWA. The weak ridge will continue to dominate, leading to a warming trend across the region through Thursday. Daytime high temperatures are forecast to be 5 to 10 degrees above seasonal averages. Valleys in western Nevada and northeast California are expected to reach the upper 80s to low 90s, while Sierra communities will see highs in the 70s to low 80s. Winds will generally be light with typical afternoon breezes this afternoon. The main weather concern of the week will be on Thursday, with increasing winds as an upper trough approaches the Pacific Northwest. Afternoon southwest winds of 10-15 mph are expected in many areas, with gusts up to 30-35 mph possible in northern Washoe County, NE CA, and the Sierra Front. The 700 mb jet will start to increase Thursday night, leading to Sierra ridges gusting up to 60 mph. These increased winds, combined with warm temperatures and low humidity, will lead to elevated fire weather concerns Thursday afternoon and evening.

Looking to Friday, a dry cold front associated with the Pac NW trough will move through the region, initiating a cooling trend. High temperatures will begin to drop, generally falling into the upper 70s to upper 80s for valleys and mid-60s to mid-70s for the Sierra. Winds will continue to strengthen on Friday across the region. Gusts of 30-40 mph are possible, with a 40-70% chance of gusts exceeding 40 mph, particularly in wind prone areas along US-395. The Sierra crest could see gusts up to 70-80 mph as the 700 mb jet max passes over late Friday morning. These winds will continue to pose elevated to locally critical fire weather conditions and create choppy conditions on area lakes.

Temperatures will continue to cool down this weekend and bottom out on Monday. Temperatures will settle into the mid-60s to mid-70s for highs in the Sierra and low 70s to low 80s for valley locations. Overnight lows will be in the 30s to low 40s for the Sierra and low 40s to low 50s for the valleys. Conditions are expected to be clear and dry into next week, although models are indicating breezy winds could linger into Saturday and Sunday.

-Justin

AVIATION

VFR conditions continue today and tonight for all area TAF sites. Wind gusts will be fairly light this afternoon out of the W/SW around 10-15kt. Winds are expected to strengthen across the region on Thursday. W/SW wind speeds of 10-15kt along the eastern Sierra and Sierra Front with gusts 25-30kt. Winds will be slightly lighter in the Sierra for KTRK and KTVL with gusts 15-20kt. FL100 winds increase Thursday evening and peak Friday morning around 40-45kt, potentially causing mountain wave turbulence and LLWS. Friday, sfc winds will increase further to where we could see gusts up to 25-35kt in the afternoon when a cold front passes through.

-Justin

FIRE WEATHER

Fire weather concerns ramp up Thursday as winds increase ahead of a cold front. Area-wide W/SW wind gusts of 30-35 mph with minimum RH values of 10-15% will yield 3-5 hours of red flag conditions on Thursday, mainly for the Sierra Front, far NW NV, and NE CA.

The front is expected to pass through on Friday, thus out ahead of it, we'll see our strongest winds Friday afternoon. The strongest southwesterly winds gusting up to 35-40 mph are anticipated to be north of I-80, although winds prone areas along US-395 in Mono County and along the Sierra Front could see gusts up to 45 mph. Minimum RH does increase slightly on Friday, especially over NE CA and far northern Washoe County. However, even with minimum RH values of 18-25%, the gusty winds may still create 3-6 hours of red flag conditions.

-Justin

REV Watches/Warnings/Advisories

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