textproduct: Reno

KEY MESSAGES

* Gusty winds will continue to pose fire and lake recreation impacts this afternoon, especially across far northeast California and western Nevada.

* Seasonably hot and dry weather prevails through midweek with very low chances of showers and thunderstorms throughout the week.

* A steady warming trend is expected late this week into next weekend, increasing the potential for widespread triple-digit heat in lower valleys and 90s in the Sierra.

DISCUSSION

The weather pattern for the short term remains dominated by a strong upper-level ridge centered over the central and southern U.S., directing dry southwesterly flow across the Sierra and western Nevada. This setup will maintain hot, dry, and breezy conditions across the CWA.

For today, gusty W/SW winds are the primary concern. Surface gusts of 25-35 mph are expected this afternoon, particularly along the Sierra Front, across far northeast California, and western Nevada. These winds, combined with very low relative humidity (RH) values dropping into the single digits and teens, will contribute to elevated to critical fire weather conditions. Winds will gradually diminish tonight, with gusts generally falling below 20-25 mph by late evening.

There's a slight chance of isolated showers/virga in S Mono and Mineral counties this afternoon, with only 5% POPs for KMMH and KHTH. Thunderstorms are not expected due to the very dry airmass and lack of instability.

Temperatures today will be seasonably hot, with lower valleys reaching the upper 90s to low 100s (e.g., KRNO 101F, KHTH 100F, KNFL 99F). Sierra communities will see highs in the low to mid 80s. Overnight lows will be mild, generally in the 50s for the mountains and 60s-70s for the valleys. By Tuesday, the upper ridge begins to retrograde westward, setting the stage for even hotter temperatures. Highs will generally be 2-5 degrees warmer than Monday, with widespread 100F+ in the lower valleys and upper 80s to low 90s in the Sierra. Afternoon breezes will persist, but generally below critical thresholds.

Temperatures will continue their upward trend, with Wednesday seeing widespread triple-digit heat returning to lower elevation valleys (e.g., KRNO 99-104F, KNFL 98-108F, KHTH 100-105F). Highs in the Sierra will climb into the upper 80s to low 90s (e.g., KTVL 82-92F, KMMH 86-96F). This heat will persist through next weekend, with daily highs in the lower valleys consistently in the 100-108F range and mountain communities in the 90s. Overnight lows will also be elevated, offering little relief from the heat, especially in the lower valleys. This will increase the potential for heat-related impacts.

-Justin

AVIATION

VFR conditions will continue across the region. W/SW winds will prevail with gusts up to 25kt this afternoon. These winds may yield minor LLWS this afternoon.

Triple digit heat will return to western Nevada terminals towards the end of the week, increasing the potential of density altitude impacts.

-Jyler

FIRE WEATHER

A brief 2-5 hour overlap of marginally critical W/SW winds (sustained 10-20 mph, gusts of 30-35 mph) and RH reductions to 5-15% will unfold this afternoon across far NE California and NW Nevada. A Red Flag Warning will be in effect from 1 PM until 9 PM PDT today for these areas. Nighttime recoveries will be moderate to poor in these areas each night, which may allow fires to actively burn overnight, especially in W NV where RH struggles to exceed 20-30%.

Winds weaken to near/sub-critical levels after today, but will still become breezy each afternoon with gusts of 20-30 mph. Along with hot and dry conditions, these winds may briefly support areas of elevated fire weather conditions each afternoon this week. Some notable potential impacts from this include: drier vegetation - especially heavier fuels, heat stress/exhaustion to fire suppression personnel, and deeper vertical plume growth on new/existing fires.

-Salas

REV Watches/Warnings/Advisories

NV...Red Flag Warning from 1 PM this afternoon to 9 PM PDT this evening NVZ420-458.

CA...Red Flag Warning from 1 PM this afternoon to 9 PM PDT this evening CAZ270-278.