textproduct: Elko

KEY MESSAGES

* Periods of valley rain and mountain snow beginning this evening, persisting through Wednesday

* Changeover for northern NV locations from rain to snow early Thursday morning

* Strong winds for northern and central NV Wednesday and Thursday afternoon

* Fair weather conditions this weekend with a gradual warming trend

DISCUSSION

(This evening through next Monday)

WEATHER PATTERN OVERVIEW: The first of two weather systems is pushing into the Silver State this evening increasing precipitation across the area. PWat values in the 0.5-0.6 range are running about twice the daily average for March 31st meaning moisture availability over the area is plentiful for meaningful precipitation amounts. The first system is the warmer of the pair in which mainly valley rain and some highest elevation mountain snow will accumulate.

The second wave, fast on the heels of the first, pushes into the Great Basin by Wednesday afternoon. This second system creates a tighter pressure gradient over northern NV Wednesday and eventually northern and central NV on Thursday to create criteria level winds needed for a Wind Advisory. In terms of moisture the best chances for meaningful precipitation will be over northern NV. Almost all precipitation that falls Wednesday will be in the form of rain but strong cold front pushes through the region Wednesday night. This will send snow levels crashing to below valley floors as a changeover to snow takes place over much of the area early Thursday morning. The unseasonably hot weather we have endured for much of March may inhibit accumulations in valleys somewhat. Current projections are a dusting to an inch along the I-80 corridor (amounts closer to 2 for summits and peaks). Higher valley amounts are possible in northern Elko County along US-93 and SR-225 where better moisture resides. 3-5 inches in locations such as Mountain City, Owyhee, Jarbidge, and Jackpot are possible. Model disagreement exists in shutoff of moisture. ECMWF guidance dries the system out sooner than its GFS counterpart on Thursday. Northern NV peaks and ridges could potentially see 1-2 feet of needed snowfall between the two systems this week.

Behind the second wave ridging builds back into the SW CONUS beginning Friday. The weekend looks to be pleasant until gradually warming temperatures and fair skies.

FORECAST CONFIDENCE & DEVIATIONS: High confidence remains in valley rain and mountain snow this evening through Thursday. Thunder was removed from Wx grids this evening and Wednesday as no appreciable model was indicating instability present, not even NAM. That combined with cloud cover today keeping temperatures somewhat subdued led to increased confidence in lack of convection with this system. NBM90 was also utilized in Wind and WindGust grids through 06Z THU.

AVIATION

Upper troughing is pushing moisture across Nevada today, bringing in VCSH and -RA conditions to the northern terminals and moving southeast towards the central terminals this afternoon. VFR conditions will the be dominant category, however MVFR and lower conditions are possible with passing storm systems. Precipitation is expected to fall as rain throughout the day with much cooler temperatures behind the front. Any lingering precipitation may transition to snow overnight, however much of the moisture will have passed by then. Breezy westerly winds up to 10-15 kts with gusts as high as 20-25 kts across all terminals, dissipating this evening. More ongoing weather is expected to continue overnight into tomorrow morning as a stronger low pressure system moves in shortly after.

LKN Watches/Warnings/Advisories

Wind Advisory from 10 AM Wednesday to 2 AM PDT Thursday NVZ030-031-034.