textproduct: Reno

KEY MESSAGES

* Warm and mainly dry conditions continue through Friday, with highs 5-10 degrees above normal and isolated Moderate HeatRisk possible in lower valleys.

* Breezy southwest to west winds develop Wednesday, then stronger and more widespread winds are favored Friday into Saturday as a Pacific trough approaches.

* Elevated fire weather concerns are possible Wednesday and especially Saturday where gusty winds overlap with low humidity and increasingly receptive fine fuels.

DISCUSSION

Warm and Mostly Dry Through Friday:

* Weak mid-level ridging over CA/NV will maintain above-average temperatures through Friday. Highs will generally reach the upper 80s to lower 90s across western NV valleys, with upper 70s to lower 80s for Sierra communities. Synoptic ascent and moisture remain limited, with only a low-end potential for isolated showers near Mono County this afternoon, generally 15% or less.

Breezy Wednesday, Then Brief Lull Thursday:

* A weak shortwave passing north of the region will tighten the surface pressure gradient and increase southwest to west winds Wednesday afternoon. The best signal for gusts of 25-35 mph remains across the Greater Reno-Carson-Minden Area, western Nevada Basin and Range, Mineral and southern Lyon Counties, and portions of far eastern Lassen County. Gradients relax somewhat Thursday before winds begin increasing again Friday ahead of the next Pacific trough.

Stronger Weekend Trough and Wind Potential:

* A deeper northeast Pacific trough approaches the West Coast late week into the weekend, although ensemble spread remains with the inland extent of stronger height falls and the associated pressure gradient. The ECMWF ensemble remains more progressive and supportive of stronger winds into northern CA/NV, while the GFS and CMC ensembles keep the deeper trough core farther offshore. Even with these differences, Saturday continues to show the strongest wind signal, with the highest probabilities for gusts greater than 35 mph across western NV and portions of the eastern Sierra. Probabilities for gusts greater than 40 mph are focused across the western Nevada Basin and Range, Greater Reno-Carson- Minden Area, Mineral and southern Lyon counties, and Mono County. Cooler temperatures follow this weekend, with valley highs falling back into the upper 70s to lower 80s by Sunday. Precipitation chances remain limited through the weekend, with most areas dry through Saturday before low-end chances return Sunday into early next week; probabilities for measurable precipitation remain generally 5-10% for western NV, with slightly higher 10-25% chances near the Sierra and northeast CA by Monday and Tuesday.

-Johnston

AVIATION

* VFR conditions will prevail through Thursday at all main terminals, with no significant CIG/VIS restrictions expected. Low- end shower potential remains confined mainly to Mono County this afternoon, with the probability of direct impacts at KMMH 15% or less.

* Typical afternoon west to southwest breezes continue today, with gusts generally 15-20 kt. Winds strengthen Wednesday afternoon as the gradient increases, with gusts of 25-30 kt possible at KRNO, KCXP, KMEV, and KMMH. Tahoe terminals should remain somewhat lighter, though occasional gusts will still be possible.

* Strengthening southwest to west flow aloft Wednesday will favor increased mechanical turbulence and periods of mountain wave turbulence near and east of the Sierra. Localized LLWS will also be possible, especially from the Lake Tahoe area southward through Mono County, and east into the Greater Reno-Carson-Minden Area.

-Johnston

FIRE WEATHER

* Recent rainfall has improved fuel moisture across portions of northeast CA, the eastern Sierra, northwest NV, and the Basin and Range. However, live fuel moisture satellite imagery still indicates a mixed fuel state across the region. Much of western NV and the Sierra Front is in the 100-135% range, with drier pockets around 75-100% where rainfall was lighter and fine fuels may be more receptive. Continued warm, dry conditions through Friday will support additional curing and drying of finer fuels.

* A brief period of elevated fire weather conditions is possible Wednesday as southwest to west gusts of 25-35 mph overlap with minimum RH in the single digits to teens, mainly across the Sierra Front, West Humboldt Basin, and Lahontan Basin. The stronger signal remains Saturday, when probabilities for gusts greater than 35 mph increase across much of western NV, the southern Sierra Front, and the eastern Sierra. The better signal for gusts greater than 40 mph is focused across the Sierra Front, West Humboldt Basin, Lahontan Basin, and Mono County. With minimum RH generally 9-15%, Saturday remains the primary window for elevated to locally critical fire weather conditions where fine fuels are sufficiently cured.

-Johnston

REV Watches/Warnings/Advisories

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