Marine Weather and Tide Forecast for Sun Valley, NV

DISCUSSION

Current Conditions Through Midweek:

* High pressure is strengthening over the region, creating a dry and stable airmass. Northeast ridge winds will persist through this morning, with gusts of 40-50 mph along exposed ridges easing by afternoon. Valley inversions will trap cold air at lower elevations, resulting in overnight temperatures below freezing in sheltered valleys and daytime highs in the 40s to low-50s. Mid- and upper-elevation slopes (above 7000-8000 feet) will warm slightly as temperatures aloft moderate.

Late Week Into the Weekend:

* A trough approaching the Great Basin on Friday will tighten pressure gradients, bringing renewed northeast winds. Most model ensembles now agree that the bulk of cold air and moisture will remain east into the Great Basin. Snow shower chances are very low, with less than a 5% probability of precipitation exceeding 0.01" over the Sierra. Ridge winds may reach 40-50 mph, helping to erode valley inversions and improve air quality through enhanced mixing.

Next Week:

* After the trough passes, ridging is expected to rebuild over the region, maintaining dry conditions and below-average precipitation chances through midweek. Strong northeast ridge winds may develop late Sunday into Monday, with a 35-50% probability of gusts exceeding 50 mph along the highest Sierra peaks.

Long-Range Outlook:

* Ensemble guidance suggests a potential pattern shift after January 25th, with some indication of modest storm activity. Confidence remains low due to significant variability among model solutions.
At this time, any storms that develop are likely to be limited in moisture and may favor northern tracks, impacting the southern Cascades and Pacific Northwest. This pattern will continue to be monitored.

-Johnston

AVIATION

Short-Term Through Today:

* VFR conditions will prevail with a dry airmass in place. Ridge winds of 30-40 kts at FL100 will create moderate turbulence over and west of the Sierra crest through 18Z Wednesday before subsiding. Calm surface winds and strong overnight inversions could result in freezing fog at KTRK early Thursday and Friday mornings.

Through Early Friday:

* High pressure will maintain reduced winds and cold valley inversions. Light frost may form on aircraft surfaces during the mornings, with limited mixing keeping stable flight conditions across western Nevada and the Sierra.

Weekend System:

* A dry cold front on Saturday could intensify northeast ridge winds, with FL100 gusts reaching 50-60 kts, likely causing turbulence over and west of the Sierra crest. The probability of snow showers in the Sierra has decreased significantly (now <5%).
By late Sunday into Monday, FL100 winds may increase, with a 35- 50% chance of reaching 40-50 kts, potentially reintroducing turbulence in the same areas.

-Johnston

REV Watches/Warnings/Advisories
NV...None.
CA...None.