textproduct: Elko

KEY MESSAGES

* Periods of valley rain and mountain snow this afternoon through Sunday evening

* A few strong thunderstorms possible this afternoon

* Marginal risk of excessive rainfall this afternoon for eastern Nevada

DISCUSSION

(Today through next Sunday)

WEATHER PATTERN OVERVIEW:

The main part of the large upper level trough that has been giving many locations much needed rainfall will finally come onshore and push through Nevada today through Monday morning. Precipitation chances will increase to near 100% this morning and remain high through out the evening before finally dropping from west to east during the overnight into Monday morning. Valleys and most lower elevation passes will see rain, with several rounds of showers and a few thunderstorms mixed in. Snow levels Saturday will start this morning at around 9000 feet, however trough passes overhead, a cold front will bring in cooler air aloft, allowing snow levels to fall around 6500 feet by Monday morning. This will allow for a brief changeover to snow for some of the higher passes like Austin, Pinto, Sacramento, as well as for NV 225 from Wildhorse to Owyhee. Mountain range peaks will see a good accumulation of snow, especially above 7500 feet. A Winter Storm Warning in effect Today through this evening for the Ruby Mountains and E Humboldt range where snowfall of over 1.5 feet is expected. Precipitation amounts have continued to trend steady, with passes and valleys seeing rain amounts of 0.10 for the Black Rock desert, up to 0.50 for the highest valleys and lower elevation passes. While higher elevation passes and mountain ranges seeing up to 1.50+ of water or water equivalent. Snowfall as temperatures cool Sunday, with a trace to 0.3 possible for the higher elevation passes passes, and up to 1+ foot of snow for the range peaks above 7500 feet. Monday afternoon, as the upper trough departs, high pressure will build in as the trough departs bringing quieter weather back into the region this ridge will be in place at least through Tuesday. Now for Wednesday, Thursday and Friday of next week, models tonight have a major change up since yesterday, in keeping a active pattern over the great basin. As both the GFS and ECMWF are in relative agreement with a pair of weaker upper level trough passing through Wednesday and again Friday bringing chances for valley rain and mountain snow showers. Temperature wise for the holiday weekend and into next week thanks to the active pattern will be relatively consistent over the weekend and into next week as highs will be near to, to slightly below normal ranging in the mid 40s to upper 50s, with lows in the mid 20s to upper 30s.

FORECAST CONFIDENCE & DEVIATIONS: There is high confidence for scattered showers and thunderstorms continuing on and off through Monday morning.

There is high confidence in high elevation snowfall with snow levels dropping to 6500 feet by Monday morning allowing for a few passes to see a change over to snow with very light accumulations possible.

There is high confidence in the return of upper ridging Monday afternoon through at least Tuesday of next week which will bring a quick calm for the region.

There is medium confidence for the upper level pattern for Wednesday and Thursday of next week, as models show a upper level trough pushing across Nevada bringing a low chance for showers, and mountain snow. There is low to low confidence of upper pattern evolution after Thursday as models show varied upper air pattern with either troughing or ridging taking place.

AVIATION

VFR conditions look to be the primary flight conditions through Sunday morning. The main energy of a strong upper level trough will pass through Nevada today through Monday morning. Precipitation chances will be near 100%, with several rounds of SHRA, and the potential for VCTS and TS for all terminals. Heavier bands of precipitation may lower CIGs to MVFR or to even IFR levels for period of time. Winds start this morning out the south to SW at 5KT to 15KT with gusts up to 25KT possible. A cold front will enter Nevada Sunday morning shifting winds to the NW at 10 to 20 KT with gusts up to 30KT possible.

LKN Watches/Warnings/Advisories

Winter Storm Warning until 10 PM PDT this evening NVZ034.