Marine Weather and Tide Forecast for South Lake Tahoe, CA

.DISCUSSION…

Little will change through Thursday this upcoming week. Daytime temperatures will stay around 5-10 degrees above seasonal averages with breezy westerly winds gusting to 20-25 mph each afternoon. The warmer temperatures will encourage additional snowmelt that will keep mountain streams and rivers cold and fast through mid week.
The only exception to this otherwise typical mild springtime period will be provided by the Tuesday passing of an upper short wave across northern CA/NV. An attendant cold front that will quickly pass through the region will boost both afternoon westerly breezes, and increase the threat for a few showers forming over NE-CA and far northern Washoe County along the OR border.

Ensemble simulations start to show signs of an approaching pattern change to more active weather starting later Thursday. A rather broad upper trough will bring periods of valley rain showers with isolated thunder, high elevation mountain snow, and breezy southwest winds by Friday that continues into the weekend. This is what blended guidance show at this time:

* Snow levels Thursday starting around 7500’-8500’ dropping to 6500’- 7000’ by Friday which eventually fall by Saturday morning to 5000’- 5500’ across NE-CA, and 5500-6000 across western NV, the eastern Sierra, and Mono County.

* A moderately uncertain projection of limited available moisture based on current storm timing and trajectory. Blended guidance is at present showing only a 15-30% chance of a very slushy 1-2 inches of accumulated snow over higher mountain passes. This may be enough to impact mountain travel especially overnight Friday into Saturday.

* Breezy west-southwest winds over the Sierra ridgetops peaking at 50-60 mph with gusty conditions mixing down into western NV with gusts to 30-40 mph. Look for choppy surface conditions across larger area lakes, and period of moderate mountain wave turbulence and LLWS for aviation concerns.

* Unseasonably colder temperatures with Sierra valleys from NE-CA, south to the Lake Tahoe basin, and Mono County seeing overnight lows dropping below freezing into the mid-high 20s for a brief few hours before day break early Saturday and Sunday mornings. If you have already started a garden, it is advise to take precautionary steps soonest.

ECMWF-Ens multi-model ensemble simulations do show a drier solution with GFS-Ens simulations projecting a slightly wetter result. Stay tuned for updates for any changes to forecast details in the coming days. -Amanda

AVIATION

VFR conditions will dominate today across all terminals. Expect light surface winds this morning, increasing from the northwest with gusts of 15-20 kts by mid to late afternoon. Winds Tuesday afternoon and evening will be strongest to 20-25 kts near the Sierra and western Nevada terminals including KSVE, KTRK, KTVL, and KRNO. FL090 winds strengthen late Tuesday afternoon to around 25-30 kts across western Nevada and northeast CA, which brings light to moderate turbulence to these areas. -Amanda

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