Winnemucca, NV 89446 Weather

Key Messages

* Periods of valley rain and mountain snow Tuesday through Friday.

* Isolated thunderstorms expected each afternoon Tuesday through Thursday.

* Cooler the latter half of the week and this weekend.

Discussion

(This afternoon through next Tuesday)

WEATHER PATTERN OVERVIEW:

Large upper level closed low pressure system is continuing to move along the California coast today, before making is turn inland tonight. This low is expected to weaken as it begins to lift into Nevada Wednesday and Thursday with the low opening up into a broad trough. By Friday morning most of the main energy will shift east into Utah as the trough splits into two pieces, with the northern half lifting into Montana and Alberta and a southern piece re-organizing into another closed low that will drift from Arizona into the four corners region Saturday. This low to trough passage will bring several periods of isolated to scattered showers and thunderstorms beginning tonight and lasting through Friday morning. Light showers will develop this evening over southern Nevada, expanding in coverage as it moves north. Wednesday and Thursday will see the best coverage for showers and storms as the main energy of the system passes overhead. Thunderstorms will be possible for eastern Nevada, with a few severe storms possible for eastern White Pine, and Elko counties as the best CAPE and mid level lapse rates will be co-located with the upper level lift. The SPC has this region high lighted for a marginal risk of severe thunderstorms with gusty outflow winds as the primary hazard. By Friday morning cooler air aloft will try and filter in, and snow levels which have been near 9000 feet for majority of time will drop to about 6000 feet just as the precipitation will be ending across northern Nevada. Timing may allow for snowfall which had been restricted to the mountain summits to reach some of the higher elevation passes on NV225 Friday morning, as total look to range from a trace to 0.2. However the range peaks look to see the best snow chances with up to a 18 possible above 9000 feet across central and northern NV. Rainfall amounts look to be good with this system as most location look to pick up from 0.25 to 0.75 in the valleys with up to 2.00 of liquid for the mountains through Friday afternoon. After Friday high pressure looks to quickly build in on the heels of the trough passage, with the ridge firmly in control by Sunday, with continued ridging lasting through Wednesday of next week.

FORECAST CONFIDENCE & DEVIATIONS:

There is high confidence for the potential for isolated to scattered showers and thunderstorms starting this afternoon, and persisting on and off through Friday morning.

There is high confidence in the return of upper ridging Saturday through Wednesday of next week.

Aviation

VFR conditions expected at all sites through the next 24 hours, however isolated showers are possible at or around all sites except KENV. Showers are not expected to reduce flight categories at this time, however they will expand and intensify tomorrow. Gusty winds are expected at KELY and KTPH today, while all other sites remain below 10KT.

Fire Weather

Isolated thunderstorms are possible in all zones through Thursday night, with activity peaking during the day Thursday. Showers are expected where thunderstorms arent, and widespread wetting rains are expected, especially on Thursday. Gusty winds up to 30 mph will be present each afternoon, although the associated fire concerns will be mitigated by the rains and moist air.