Westerlies continue to pick up strength as pressures aloft build into CA the next few days for some warming….Wet Pacific NW frontal system will sag south Friday leading to Breezy weather Friday Afternoon and stronger winds Friday night….Then light snowfall for the high country Saturday PM….Winter Outlook Looking wetter now for CA….
Wednesday October 22, 2014
Posted at 8:21 am by Howard
Thursday Midnight Special Update:
Longer Range Global Models GFSX and ECMWF have a significant Storm System bringing the possibility of a foot+ of snowfall, the last weekend of October into the first few days of November. The GFSX is more progressive bringing it in the 31st of October while the ECMWF is slower with the system for later in the weekend. Stay tuned to this 1st developing significant storm for the Eastern Sierra.
Thursday: This mornings Satellite motion showed a well-developed AR (atmospheric river) Stretched between the OR/CA border and north of Hawaiian Islands. The rainfall event is now on for the Pacific NW with up to 9 inches+… expected storm totals in some areas. The Nino 3.4 region has bumped to +.6C as of the 19th of October and another .4C of warming over the next few months would be considered “Moderate” and make a difference in our winter weather….. the Positive phase of the PDO has also strengthened September over August and indications show signs of further strengthening in October…. Of Note: The Snow Cover is 5X that of normal south of 60N over Eurasia. Normally on this date there is about 1 million squared kilometers of snow cover south of 60°N across Eurasia and instead, this year there is 5 million. Usually there is a strong correlation of this anomaly to a strong -AO which can send arctic air south over the US. The big question will be what will be its trajectory? If Eastern California is going to be effected, it will most likely be in December. Watch out for an exceptionally cold December over the Great Basin!
WX Outlooks: ECMWF has a storm for Central and Southern California the very end of October into early Nov. The GFSX 00z Friday has the same storm for All Hallows Eve….. Stay tuned….>>>> The CFSv2 has Central and Northern CA in for a wet November……
Some light rainfall and high elevation Snowfall is expected in Mammoth Saturday….It will be Breezy Friday night with stronger winds Saturday with possible wind advisories… High temps will cool to the upper 40s by Sunday/Monday.
From Wednesday: A brief forecast for this morning shows warmer days through Friday with highs returning to the mid to upper 60s and lows in the 20s and 30s. Winds will be light overall until Friday, when they will increase in response to a southward push to the upper jet. The weekend outlook looks unsettled with wind early, light snowfall Saturday then cooling into Sunday….. It is nice to see some positives with Winter forecasts, for at least a normal amount of snowfall for the high country this winter. WeatherBELL Analytics is a fairly new company. It was started just a few years ago by Joe Bastardi, former hurricane and long range forecaster for Accuweather…. and Joe D’Aleo, the first Director of Meteorology for The Weather Channel. The just released winter forecast shows that for the Mammoth area, about 117% of the normal amount of precipitation can be expected between December and the end of February. That’s a lot of snowfall here in our area! The temperature graphics show above normal temps….not all that surprising for an expected weak to moderate El Nino winter. I mention WeatherBell because it did a pretty good job last winter. Now I will say that other forecasts are not as positive, like WXrisk.com indicating below normal precipitation and above normal temps. The National Weather Service uses more bias in the way they come across in there forecasts, indicating that there is an equal chance for either a wet winter or a dry winter here in the central sierra. They all agree on above normal temperatures. The CFSv2 the climate forecast model is wet for California and even gets it going on in November……
What the Dweebs Think…………… Here is what I see: 1. The PDO after being negative (Cold SSTA’s) switched to positive (warm SSTA’s) along the west coast last spring and early Summer. However since then it began to weaken in its positive phase until last month. The indices jumped back up from .67 in August up to 1.08. Why is that important? You may have noticed that significant El Nino’s have been absent for quite a while. There is a coincidence to that. During this phase of the PDO cycle which can last 20 plus years El Ninos are less common and are generally weaker. The fact that we are seeing a strengthening +PDO “may lend” support to the fledgling El Nino that is trying to get going. The way the cold SSTAS are extending eastward from the NW pacific toward the east central pacific is a positive sign for the occurrence of higher AIM and further development to a Significant warm ENSO phase this winter. 2. The SSTAs off Baja are at historically high levels since 1949. This would provide fuel for the storms to act upon this winter. Snow cover is rapidly increasing over eastern Siberia giving support to a -AO winter. That tends to provide more meridial flow or blocking…. More Later……………………………………..—- Dr Howard and the Dweebs………………………:-)