Although it will be a cooler day today, high pressure will build over the Eastern Sierra Sunday into Monday for a couple of very nice fall days. High temperatures will reach well into the 60s.

The big news this morning is that the European and GFS models are coming into more agreement (With timing differences) with a good October storm that has the potential to bring good moisture to the Eastern Sierra. Both the European and GFS have a decent “AR” subtropical connection that hits Central CA on the 144hr prog. PWAT (Precipitable Water) tools shows amounts over 1.5 inches moving on-shore later Thursday afternoon. The plume pushes through by 12:00PM Friday on the EC and by Friday night in the GFS model. The snow levels fall in both models as the SW fetch and plume passes from north to south Friday. With any AR, the main questions that come up are how cold it will be during the AR and thus how much snow will fall at what snow level. Best odds are that the majority falls above the Town of Mammoth Lakes Thursday and Thursday night with snowfall most likely Friday in town after most of the plume has pushed south. This is just a rough idea at this point in regards to the timing in the Towns of Mammoth and June. During the meat of the AR, higher elevations could pick up several feet.
Although it is way to early to be specific on amounts, there is much agreement with the two favored global models at this time that a potential wet storm is on its way after mid-week next week. The storm looks to be out of here by Saturday.

More winter thoughts:

1. The National climatic center came out with a report that indicated that La Nina is expected to be a weak La Nina. If true that increases the odds for more AR events this winter. Remember, the highest winter incident’s with AR’s occur when ENSO is +.5C to -.5C in the ENSO 3.4 region. Conversely, strong El Ninos and Strong La Ninas have the lowest odds for AR events, statistically.
2. Another important key to this winter or any winter is where will the blocking set up? Last winter it was over AK and west in the WPO and EPO region. Unlike last winter at this time, both of these teleconnections are showing strong positive phases through the next 10 days so much more low pressure in this region at this time. (ANTI BLOCKING)
3. Were still dealing with an easterly QBO vs a westerly QBO with last winter which tends to keep the upper jet further north. However, there is an early buildup of snowpack over Eastern Asia which favors a negative phase NAO and AO.
4. Odds are that we will have more meridional flow this winter.
5. So the winter from a long-range forecast point of view is still quite the mystery. However, no matter how this winter ends up, it should be a good one!

PS. The Dweebs will focus on the next 2 weeks and use MJO to offer a glimpse beyond……:-)