Wednesday, December 22, 2010


Updated 2 pm:

Getting a little bonus snow this morning on top of the dump from the weekend. With the negative tilt and South to North orientation of the storm it is hard to push the snow over the crest. The snow finally pushed over the crest this morning and it was snowing steadily. Northstar picked up 1-2 inches overnight and we should see a couple more inches today. We won't be able to have complete totals for this storm until tomorrow morning since the steadier snow started after measurements were taken this morning.

Beautiful weather with mild temps Thursday-Saturday. Then the jetstream looks to return Saturday night with a moderate sized storm. The storm initially will have negative tilt like today's storm, but then the jetstream will punch in and push the moisture over the crest and into Tahoe. Because of this the liquid amounts look to be up to an inch for the Tahoe Basin up to 1.5 inches on the crest. That would equate to 6-12 inches in the Village and 12-18 above the base lodge. I have more confidence in snowfall totals with this storm than today's with the support of the jetstream this go around. I am also driving back from the in-laws on Sunday through Lassen Park and the mountains down 395, so I am sure with my luck that it will snow hard so that it takes as long as possible to drive home with a 2 year old and newborn in the car.

Then we get another break Monday and Tuesday before another storm Wednesday-Thursday of next week. The ridge is looking to set-up a little more East today so that would bring a cold storm in. Right now it does not look all that impressive, in the 6-12 inch range, but that could change if the jetstream taps some more moisture. The flow looks to stay progressive with another ridge setting up around 150w allowing another cold storm for New Year's weekend.

Looking long-range I am a little concerned. The teleconnections have the PNA going positive and the NAO going negative the first week of January. Of course this is long-range but that could spell ridge city along the West Coast. What has saved us through the NAO being negative this fall is the PNA has stayed negative allowing the stronger than normal jetstream to have direct aim at crushing any ridge that tried to form on the West Coast. If it goes positive that may mean the good bye strong jetstream as it retreats North. In La Nina Alaska should get slammed by the Polar jetstream and they have gotten nada so far. This may just be the atmosphere trying to transition into a true La Nina pattern the first week of January, and then we flip to troughing on the West Coast and ridging on the East Coast.

What could save us as usual is the MJO as it is forecasted over the next two weeks to slowly strengthen and break out of it's loop into the Wester Pacific. That would normally grab the ridge and pull it back from the West Coast to North of Hawaii and bring us a cold storm series. We should see the ridge form just South of the Aleutians in January and the Pacific jetstream come underneath into the Pacific NW and CA. I am expecting lots of snow in January, but I'm not psychic just lucky a lot. We will have to watch things develop the next couple weeks. Stay tuned..........BA

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