textproduct: Elko

KEY MESSAGES

* Breezy and cooler weather conditions today

* Cooling temperature trends continue this weekend with high temperatures several degrees below normal

* Storm system moves through NE Nevada Sunday into Monday, bringing gusty winds, and chances for valley rain showers and mountain snow showers.

* Overnight lows are expected to drop to below freezing Sunday morning and continuing into early next week

DISCUSSION

(This afternoon through next Saturday)

WEATHER PATTERN OVERVIEW: Upper trough of low pressure is pushing into the southwest today with the central part of the low pressure expected over northern Nevada by Sunday. This trough of low pressure will push much cooler air into Nevada with highs today expected to be just a few degrees below normal in the 60s, with high temperatures tomorrow expected to be 10-20 degrees below normal. Overnight temperatures will be below freezing and expected to reach below freezing until mid-week. The trough will tighten the weather gradients that will aid in increasing wind speeds over the weekend. Northerly winds this afternoon up to 10-15 mph with gusts up to 20-35 mph. By tomorrow, winds are expected to be stronger with speeds up to 20-35 mph, gusts as high as 40-55 mph. Recent model runs showing an increasing trend for precipitation chances for rain/snow, however confidence remains low as models are still split on how much precipitable moisture will be in the atmosphere as some models show only 0.3 inches. The track of the storm now has chances for precipitation spread across the entire region with higher values expected over White Pine County, with probabilities of up to 75-95% of seeing more than 0.05-0.1 inches of rain (more than 0.2 inches possible for White Pine County). Thunderstorm chances have also trended upwards with a 20% chance along the US-50 corridor in the afternoon. For northern Nevada, precipitation may start out as snow reaching the valleys as snow levels drop below 5000 feet tonight, yet see slight warming Sunday with snow levels increasing back up around 5500 feet, then dropping again Sunday night around 4000 feet. Central Nevada will have snow levels higher, starting around 8000 feet, dropping to around 6000 feet overnight then back to around 7000 feet Sunday afternoon. Sunday night, snow levels drop below 5000 feet as freezing temperatures move across the region. Snow accumulations are not expected to be less than an inch for the valleys (up to an inch in northern Elko County along SR-225 and US-93), with passes and summits up to 1-2 inches. Mountains will see up to 4-8 inches of snow with Ruby Mountains and Snake Range seeing up to a foot of snow.

Monday, quiet weather conditions return as the trough moves eastward out of Nevada. Temperatures expected to remain below normal through Tuesday in the 60s as northwesterly flow stays over the state but is expected to see a warming trend. By Wednesday, temperatures warm back to near normal in the 70s with Thursday and Friday reaching slightly above normal in the 70s to 80s. Next weekend, models are showing another Pacific low pressure pattern that will enter into the western CONUS, however discrepancies in the models on how strong the system will be which may change the timing and position of the low as next weekend approaches.

FORECAST CONFIDENCE & DEVIATIONS: High confidence of cooling temperatures trends dropping below normal with overnight freezing this weekend. Low confidence of precipitation Sunday as PWAT values remain low. High confidence of strong gusty winds Sunday afternoon. Moderate confidence of below normal temperatures through next week, followed by warming temperatures above normal late-week. Adjusted winds in NBM grids to better anticipate tightning pressure gradients.

AVIATION

Breezy northerly winds across all terminals this afternoon with speeds up to 10-15 kts, gusts 20-30kts with the strongest of winds more towards the northern terminals. Cloud levels expected to increase in coverage with the lowest CIG levels maintaining around FL080-FL100. Overnight into the early mornings, CIG levels drop down to FL030-FL050 as trough of low pressure brings in precipitation chances. VCSH conditions starting over the northern terminals in the morning, and reaching the central terminals by the afternoon. VFR conditions dominant, however MVFR or lower is possible with the chance of -SHSN over northern terminals as temperatures drop below freezing overnight. Sunday afternoon will warm with -SHRA conditions over all terminals until -SHSN conditions return overnight due to freezing temperatures.

LKN Watches/Warnings/Advisories

Wind Advisory from 11 AM to 11 PM PDT Sunday NVZ030-031-035-037-040-041.