textproduct: Reno

KEY MESSAGES

* An early season storm will bring impactful Sierra snow today through early Wednesday with periods of rain for lower elevations.

* Below average temperatures continue through this week with drier weather later in the week.

* Another chance for valley rain and mountain snow may arrive by late this weekend.

DISCUSSION

Near-Term: Today-Wed AM

* Current radar imagery is showing a round of moderate precipitation moving into Mono and Alpine counties. Local camera networks and snow level profilers are showing current snow levels around 6,500-7,000'. Snow levels will remain steady around 6,500' this morning. For the rest of today into Wednesday, the CAMs and HREF output are in better agreement showing the upper level low moving into the central CA coast by the early afternoon. The low then tracks into Mineral and Esmeralda counties by the late evening, and into northeast NV by Wednesday afternoon. Afternoon highs today and tomorrow will continue to be 15-20 degrees below normal with overnight lows below freezing through at least Thursday morning.

* For the Sierra, most of the precipitation this morning will be south of US-50. By the late morning, precipitation becomes likely in the Tahoe Basin/southern Lassen County where it continues through early Wednesday morning around 3-6 AM. Precipitation becomes more showery in nature by the afternoon for Mono County, ending around 8-11 PM. For today's snowfall amounts, the HREF/NBM have a likely (>70%) chance for at least 12 inches of snow above 7,000' throughout the eastern Sierra. For locations closer to 6,000'(Truckee, Verdi, etc.) the NBM shows a low (<10%) chance for at least 6", reflecting the still high uncertainty in snow levels.

* For western NV, precipitation moves into Mineral, Douglas, Lyon counties by 7-9 AM, and the greater Reno Metro area/I-80 by around 11 AM to 1 PM. Precipitation continues through 3-5 AM Wednesday. There is still some uncertainty to exactly how far north band this precipitation band sets up. So far, ensembles point to roughly I-80, Pyramid Lake. As for snow in western NV, blended guidance and the HREF show a high probability of precipitation becoming all snow above ~6,000' by 7-9 PM with a 50% chance for at least 4" of snow in the Virginia Range and a likely (>80%) chance for 4" of snow in the higher elevations in Mineral, Douglas, Lyon, and Washoe counties. For that reason, a Winter Weather Advisory has been issued for portions of western NV above 6,000' for tonight. -McKellar

Longer-Term: Wednesday PM-Tuesday

After Wednesday afternoon, drier conditions will return as the low pressure moves out of the area. Daytime highs will come back up to near mid-October normals by this weekend. Long-range guidance shows another low pressure system dropping down from British Columbia as early as Sunday, bringing chances for valley rain, mountain snow, cooler temperatures, and gusty winds.

-Giralte

AVIATION

* -SHRA for Sierra Front terminals likely today from around 18-20z through 09-12z Wed. This will bring MVFR/IFR in showers and low ceilings.

* For KTRK/KTVL: -SHRA likely in the morning. This will then become -SHRASN by around 22z and all -SN after 00z. This will produce MVFR/IFR in ceilings and visibilities as well as mountain obscurations. Precipitation continues through 10-14z Wed. There is a 20% chance for at least 1" of accumulations. KMMH will see -SN to at times +SN through 06-10z. Localized LLWS will be possible for KMMH today until 18z. -McKellar

REV Watches/Warnings/Advisories

NV...Winter Weather Advisory until 11 AM PDT Wednesday NVZ002.

Winter Weather Advisory from 11 AM this morning to 11 AM PDT Wednesday NVZ001-003.

CA...Winter Weather Advisory until 11 AM PDT Wednesday CAZ072.

Winter Storm Warning until 11 AM PDT Wednesday CAZ073.