textproduct: Reno

KEY MESSAGES

* Warmer than average temperatures persist through Monday, area waterways continue to run dangerously cold and swift with continued snowmelt.

* Showers and thunderstorms expected each afternoon through the holiday weekend, posing impacts to outdoor activities.

* Gusty winds will bring aviation, recreation, and fire impacts Monday and Tuesday with cooler, showery weather from mid to late week.

DISCUSSION

Showers today will migrate southward as the shortwave moves over central Nevada, bring the best chances (25-45%) over Mono County early this afternoon. Then, chances taper to around 20-35% and move over eastern Mono and western Mineral counties for early evening. Overall, winds will be light and variable this morning, but will become westerly as gusts of 15-20 mph arrive for the afternoon. One exception will be in the vicinity of any decaying storm, where gusty outflow winds may reach 35 mph. Other hazards with these storms may consider a 20-25% chance for embedded lightning, potential for heavy rain, pellet showers or small hail. Additionally, gusty winds associated with storms may bring choppy lake waters, blowing dust over desert sinks.

Monday will be our last day of warm weather, it will also see returning shower chances to Mono County (10-25%) for the afternoon. Elsewhere, to the north, gusty westerly winds will be on the increase Monday afternoon. The higher gusts will be found across northern Washoe and Lassen counties into Surprise Valley in Modoc County. Gusts of up to 45 mph are possible for these areas. Further south, across Pershing County, gusts of up to 40 are more likely, as the bulk of the winds will be found along the Oregon Border. This, along with poor overnight relative humidity recoveries and low daytime RH readings, has prompted the issuance of a Fire Weather Watch. See more detail in the Fire Weather section of the discussion below.

Those winds will signal the incoming cold core closed low that will drop in from colder Canadian air and drop our temperatures back into mid April territory. This will be about 5 degrees below seasonal average by Wednesday, when widespread shower chances arrive. This low, as mentioned, will draw down cold air that will bring snow levels toward 7000-7500 feet by Wednesday morning. This will introduce snow chances for our higher peaks, although amounts look on the light side fo accumulations, with only 1-2 inches for peaks around the Tahoe Basin, and 2 to 6 inches along the Sierra Crest in Mono and southern Alpine counties. Given that this closed low is slow to move out, shower chances, chilly temperatures and gusty to breezy wind will be our flavor of the week through Friday.

A weekend warmup awaits us on the other side of this chilly week ahead. HRICH

AVIATION

* VFR conditions are expected for most E.Sierra/W.Nevada terminals today with typical afternoon westerly gusts around 15-20 knots. KMMH could see showers this afternoon, 30-40% chances after 20z, with 15-20% chances of isolated thunderstorms which could yield MVFR conditions from brief heavy rain along with lightning, gusty outflow winds, and small hail.

* A strong cold front is expected to produce strong and gusty winds Monday into Tuesday. Wind gusts up to 30-40 mph will be favored mainly northward of I-80 on Monday before shifting south of US-50 Tuesday afternoon as the front moves through.

* Expect increasing chances for turbulence, LLWS, and areas of reduced visibility due to areas of blowing dust which could impact KLOL, KNFL, and KHTH. Fuentes

FIRE WEATHER

* Critical fire weather conditions due to gusty winds and low humidity are expected Monday afternoon and evening as a strong cold front approaches the NE California and NW Nevada.

* A FIRE WEATHER WATCH remains in effect for eastern Lassen County, the Surprise Valley, N.Washoe County, and the western Humboldt Basin, including the Quartz Fire (NE Pershing County) in anticipation of gusty winds and low RH Monday afternoon.

* Southwest to west winds will increase early Monday afternoon with sustained winds of 20-30 mph with gusts up to 45 mph across NE California and N.Washoe County. Areas across Pershing County (W.Humboldt Basin) may see gusts a touch lower around 30-40 mph. Minimum relative humidity is expected to be around 10-15%.

* The duration of critical wind/RH is trending towards 3-7 hours in Lassen and far N. Washoe County with 3-6 hours in Pershing County.

* Uncertainty remains on the continuity of receptive fuel beds, but local intel from local fire partners and the recent Quartz Fire ignition suggests the cured grasses and sagebrush will be capable of carrying fire in valleys/midslopes of far NW Nevada. Farther south, elevated fire weather conditions will be possible, but fuel conditions aren't as dry per local units.

* Winds remain elevated on Tuesday and will shift from southwesterly to north/northwesterly as a cold front sweeps through the region. Temperatures cool and humidity rises behind the front, with increasing chances of showers Wednesday and Thursday. Salas/Fuentes

REV Watches/Warnings/Advisories

NV...Fire Weather Watch from Monday afternoon through Monday evening NVZ423-458.

CA...Fire Weather Watch from Monday afternoon through Monday evening CAZ270-278.