Never miss a beat! Receive The Tahoe Daily Snow via email the moment it's written. Start your FREE OpenSnow Super Pro trial today!
From 8 a.m. Forgot to hit Submit...
The first system moved through overnight leaving a dusting of snow on the mountains and cold air in its wake. The jestream will setup over Northern CA on Thursday with rain just to our North. Over the weekend low pressure moving into the Pacific NW will push a front and the precip through the area with rain and mountain snow with falling snow levels.
Woke up to a very light dusting on the mountains West of the basin along the crest. Temperatures this morning are only in the 20's in Truckee. The weather will stay active this week with the jetstream setting up a river or moisture across Northern CA Thursday. The models all keep the precip just to our North through Friday so we should stay dry but may have some clouds and windy conditions.
Friday night an upper low approaches the Pacific NW and moves inland over the weekend. This will push a front and precip through the area. The GFS forecast model pushes the precip through Friday night into Saturday with most of the precip to our North. The European and Canadian models show the system possibly splitting with the precip pushing further South into our area and down the Sierra. They are also slower with the precip coming Saturday into Saturday night.
The snow levels will start high but could drop down near 7000 ft. during the event and to lake level at the end as the colder air behind the front moves through. Here is the GFS precip forecast with light amounts for us.
This scenario would be similar to last night with a dusting of snow possible for the mountain tops. Now here is the normally over aggressive Canadian forecast model for total precip through Sunday.
Not buying this much precip. The Euro is in the middle of the road with around a half inch of liquid possible. If the system starts to split and more precip makes its way further South we could see several inches of snow on the mountains above 7000 ft. Saturday into Saturday night.
The pattern looks like it will stay active to our North in the Pacific NW week 2. This is normal in the early season as the jetstream is still further North. I showed the CFS November forecast for precip in the last post which this week has been showing a wet month for CA against the average.
We can also look at a few of the latest model forecasts for Winter precip Dec-Feb. First here is the latest JAMSTEC run showing the above average precip further North now into Northern CA vs. some of its previous runs.
And the UKMET showing a similar pattern with a Northern CA bullseye.
And the CFSv2 with a wet CA.
So some good signs on the climate model forecasts coming out this week. The problem with long-range climate models though is that you should trust them as far as you can throw them. They miss the mark often in the Fall.
One of the big differences this season is that there is not a warm pool of water off the coast. It is along the West Coast. The climate models have a trough off the coast for the Winter and not a ridge. They have the ridge along over the Pacific NW up into Western Canada and try to push the trough into CA for the Winter.
On the other side looking at the analog years 03-04 and 76-77 look very similar to the pattern we could have this Winter and both were below average snowfall year. Like the Winter forecast showed in the last post the SW has a much better chance of seeing above average precip. For Northern CA it still looks like there are as many factors that could bring us a dry Winter as a wet one. For now let’s at least hope for an average precip season and snowfall season.
A change in the weather Monday into Monday night. Light precip possible with snow levels dropping near 7000 ft. or slightly lower. Warmer weather the second half of the week before another system is possible next weekend.
After several days of quiet weather we will see another change tomorrow as low pressure moves in off the Pacific. Not expecting a lot of moisture from this system, just some light precip. The center of the low will be cold so we will see snow levels drop around 7000 ft. Monday evening, possibly a bit lower. That should only equate to a dusting of snow on the moutains when we wake up Tuesday morning. Here is a look at the total precip forecast from Canadian model which is one of the more aggressive runs.
The system clears out by Tuesday but leaves behind some colder air. We will warm up the second half of the week back into the 60's at lake level.
The trend on the models the past 24 hours is for another system to dig down the West Coast next weekend. This one could bring heavier precip if it digs far enough South. All of the forecast models show a chance for precip next weekend but the Canadian is the most agressive with precip amounts right now. Snow levels could be low enoug for mountain snow with this system if it pans out.
Looking at the long-range pattern there are no signs right now of a long-term ridge that would keep us dry for a prolonged period. We could see more troughs push into the West Coast going into November. The trend on the CFSv2 climate model the last few days is for a wet November.
When we looked at the Winter forecast ideas last month we talked about the possibility of an early start to the storms this Fall with the weak El Nino conditions developing. The question is how with the rest of the Winter pan out? My thoughts were and continue to be that we will be right on the edge between above average precip to our South and below average to our North. The rigde is expected to sit along the West Coast of Canada down to the Pacific NW much of the Winter with the Southern jet coming underneath into Southern CA. Below is the latest Winter forecast map from accuweather that lines up with what we have been thinking.
You can see why we could have a 50/50 chance of an average or below average season for precip. The second question will be snowfall vs. precip. Even with an average precip season we will need low snow levels for a good snow year. Let's hope we can get enough cold and the storm track is far enough North this Winter. We'll take the precip either way.
The trend over the past couple of days has been for the GFS to be further North with the systems this week. That's now in line with the other models. We will see some wind, clouds, cooler temps, and possibly some light precip Tuesday into Wednesday as the cold front pushes through the area. Another system may brush us again next weekend and the beginning of the following week.
For now nothing significant in the forecast, just a more active pattern to our North.
I have been watching the forecast model runs all week. They continued to show the ridge off the West Coast being replaced by a trough next week with a couple of systems possibly bringing us precip. The trend was that the first system Tuesday stayed just to our North and then possibly the following system digging further South next weekend.
Today the runs of the GFS model started digging the trough further South Tuesday into Wednesday with up to an inch of liquid along the crest. Some of the other models are not in agreement yet. The European model is slightly furthern North with only light precip, and the Canadian model is keeping all of the precip to our North.
Here is the total precip forecast from the latest GFS run.
And the Canadian
The snow levels on the GFS and European model runs are around 8,000 ft. for most of the event dropping to 7000 ft. near the end as the cold front passes. We will keep watching the next few days to see how far South the system digs and how much precip we could see.
After that another system may push in next weekend as another trough pushes into the West Coast. Right now that one looks like it will keep most of the precip to our North with only light amounts possible.
Another system may push in behind that as the ridge stays well off the coast and troughs drop into the West Coast. The MJO strengthening in phase 1 is a positive sign for this more active pattern coming up as well. Overall the wet season looks like it will be getting started for the Pacific NW the next couple of weeks. We will be right on the Southern edge of the active pattern so we will watch each system to see how far South they could come.
I posted last week that we could see a pattern change around mid-month. Some of you have been asking for an update. October is usually a quiet month, especially to start, but it can bring decent snows later in the month. Last year the mountains saw a decent storm that dropped 1-2 feet in late October.
The forecast models in the unreliable long-range continue to show the ridge off the coast being replaced by a trough by the end of week 2. I am continuing to watch the runs each day and other variables going on. Still watching for a possible pattern change to cooler and possibly stormy around mid-month possilby due to remnants of a typhoon moving across the North Pacific next week. I will update as we get closer.
I am also watching the patterns develop that could affect our Winter weather. Some of you have asked for a Winter forecast. I have already posted 2 long discussions about the upcoming Winter in September if you look back through the posts. I plan to have a Winter forecast out before the end of the month.
For now the weather will get slightly cooler the second half of this week but we should stay dry for the next 10 days. Then maybe a change.