Weather Geek Update

Weather Geek Update: December 31, 2009The New Year appears set to arrive Friday with a new storm. Actually, the next storm should be pushing its way into Tahoe by late this afternoon or tonight. A low pressure system off the coast of California was already moving inland this morning, bringing rain to the coastal mountains and as far inland as Redding. The storm is expected to bring snow to the Lassen and Plumas county regions by midday and sag toward Interstate-80 in the afternoon.Most of Friday should be stormy in Tahoe, especially to the north and along the Sierra Crest. As you can see on our Pacific Satellite shot pictured here, this is a warm storm tapping into some subtropical moisture, and snow levels will likely rise above 6,000 feet and toward 7,000 feet in Tahoe. That means the snow to water ratio will be low, limiting snow production. Accumulations will not be huge but will add a few more inches to our base: probably 6 to 12 inches between 6,000 feet and 7,000 feet and a bit more above 7,000 feet. Winds will be gusting toward 40 mph or 50 mph for part of the day Friday.

Once that storm exits on Saturday, a ridge of high pressure should keep the weather calm and the skies clearing into the weekend. A series of storms pushing through the Pacific Northwest will try to make it over the ridge, but at this point they appear likely to bring Tahoe only some clouds and perhaps some light showers on Monday and maybe Thursday. The next real winter storm that looks possible in the forecast models is for the second weekend in January, but that’s too far out to bank on.

For now, stay safe on New Years Eve as this storm moves in, and enjoy the bluster on New Years Day. It might be a good one to stay inside and watch some football, unless you are partial to warm storms, wind and wet snow….

Check www.tahoeloco.com for updates as this storm arrives, and for the first word on what’s coming over the horizon.

El Nino Watch

ninoThe El Nino condition that has been present in the subtropical Pacific since last summer just keeps getting stronger, with sensors recording the greatest variation above average for sea surface temperatures this year in the final full week of December. Temperatures in the central sub-tropic region that is the key El Nino indicator rose another tick to 1.9 degrees Celsius above average. That’s well into the range considered a “strong” El Nino event if maintained for three consecutive months. The graphic above shows the trend for 2009, with an initial surge, then a lull in late summer and a renewed increase in temperatures this fall and early winter. Forecasters at the US Climate Prediction Center and elsewhere still expect the El Nino condition to last at least until spring and bring greater than average precipitation to Southern California in the latter half of the winter, and below average precip in the Pacific Northwest. Tahoe sits between those two extremes and its weather will depend on how far north those big southern storms come. Typically, San Francisco, Sacramento and Tahoe get above average precipitation in a strong El Nino year.