Colder air has moved in with the trough pushing through. A weak system could bring a few flakes of snow this evening. Highs only in the 30's on the mountains today and Thursday, and 40's at lake level. Friday and Saturday we have slightly warmer temps ahead of a colder trough. Sunday into Monday the next cold trough pushes down from the Gulf of Alaska bringing colder air and snow. We could see 3-6 inches on the mountains and a few inches to lake level. A second slightly stronger system is on the heels of the first by Tuesday. We could see several more inches of snow with this wave.
We could see a break the second half of next week before another cold trough may push in the weekend of the 10th. This pattern may continue through mid-month.
It's a cold morning around town with lows dropping to the teens overnight in the valleys. We will stay cold the next couple of days. Weak forcing from a system to our North could produce a few snow flakes as far South as the lake this evening. Not expecting any accumulations.
Still on track for a cold trough and snow starting Sunday. My daughters birthday party is on Saturday and we rented a bouncy slide. I was getting worried it could get windy and cold by Saturday when I ordered it last week. It looks like we will get the party in just in time before the colder weather, wind, and snow.
The forecast models are trending a little wetter this morning and in better agreement with the first wave of snow for Sunday into Sunday night. We are within 5 days now (finally) with a storm so we can start looking at potential snowfall amounts. Taking a model average of the latest runs it looks like we could see 1-3 inches at lake level and 3-6 inches on the mountains by Monday morning.
Here is a look at the total precip forecast on the GFS through Monday morning.
The model trend has been to speed up the 2nd wave again and bring it in on Tuesday. This wave could be slightly stronger but it is a little early to talk about exact snowfall amounts. The trend right now is that we could see several inches to over a foot along the crest with the 2nd wave.
Here is the GFS total precip forecast updated through Wednesday morning.
and the Canadian, can't republish the Euro but it's similar
By the time the pattern change arrives we will have been tracking it for a couple of weeks. So it is the first time this season the models have been right on a pattern change a couple weeks out. The difference this time was the teleconnection support and it being Spring. Especially the MJO support.
We may see a break the 2nd half of next week but the ensemble runs are showing decent agreement another trough could drop in the weekend of the 10th. The ridge stays in the central Pacific.
The GFS ensemble runs and some runs of the Canadian show the pattern continuing through mid-month, while the European model runs show an end to the pattern after the 2nd weekend. One of the reasons the GFS may continue the pattern is the MJO forecast looping back into the same phases we are going through now that helped with the pattern change.
The Japanese model shows it happening before phase 4 and tends to be one of the best MJO forecast models.
So for now the pattern has changed. It's colder. Then we will change more Sunday through Tuesday adding in snow. We could continue to see shots of colder than average and snow for a couple of weeks.
P.S. Tahoe Ski Bum came out with a T-Shirt for those of you who survived this Winter. "I Survived the 2014-15 Winter". Even though it is not done yet, I feel like a survivor... we need a change next year.