A vertically stacked upper low at 500mb was located at 51N 140west this morning due east of a negitive tilted upper ridge. The upper low is progged to become stationary west of the Columbia River at about 130West tomorrow Friday. It then deepens due south along 130West through Sunday afternoon. Several short waves will move though the long wave position into the west coast through the weekend until this main long wave trof is ejected through California Monday. Three significant short waves will effect the Mammoth area this weekend. The first one will kick though mainly after midnight Friday night with about a  9 to 12 hour period of heavy snowfall between about midnight Friday night and 12:00 noon Saturday. One foot plus is possible on Mammoth Mountain as the Snow to H20 ratio will be higher with this system. At least 12:1…. The air mass is not as moist as the last as its source region is maritime polar.

Additional short wave action and UVM will continue snowfall through the afternoon Saturday so that by Sunday AM another 4 to 8 inches is possible over the upper elevations.  SW winds at 925mb to 850 MB of 30 to 35 knots and up to 50 knots at 700mb should favor some heavy precip for the central sierra especially between midnight Friday and 5:00am Saturday.

By Sunday morning, the mother “long wave” begins to eject into California with most of its energy focused upon the southern half of California. LA should get a lot of rain Sunday afternoon and Mammoth should get a lot of snow. At least a couple of feet Sunday/night.

More detail coming later………………………………………:-)


Reference Glossary of Weather Terms
Disclaimer: I have been a hobbyist meteorologist for over 30 years here in the Mammoth area and I do this for my personal enjoyment. The National Weather Service saves lives every day . . . I do not. When making important planning decisions please use information provided by the National Weather Service as they are the most knowledgeable and accurate information source available today.