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Archive for November, 2020
Cold Winter Like Weather to bring snowshowers over Mammoth Mt today along with Mid Winter Temperatures…..After a break early next week another wetter storm moves in Friday……
Sunday November 8, 2020
Tuesday AM the 10th:
Beautiful morning with Mammoth snow covered. Cold with morning lows in the single digits and teens.
Weather pattern this morning shows NW flow with short wave bringing high clouds to our area. Precip in Pacific NW with sheering trof and energy forecasted mainly east over the Northern Rockies. A warm air advection pattern follows with gradually rising snow levels over the weekend. This next system to effect the Mammoth area is expected to bring mainly light amounts of snowfall, up to 4 tenth of an inch H20 EQ currently forecasted. So a few inches possible. It may begin as snow in town but turn to rain later in the weekend at elevations below 8K. Warm air advection pattern can be trickier with snowfall est. Models do not do as well as dynamically induced precip. Feel comfortable in the 3 to 6 inch range between Friday and Sunday at this time over the Crest. Much less in town with rain/snow mix at the end. Next WX system Tuesday or Wednesday next week.
Longer Range:
Based upon NCEP’s tropical discussion today, the MJO weakened as it moved over the colder waters of La Ninia. It will enhance upper divergence over the far Eastern Pacific and Caribbean this week, before it emerges over the Indian Ocean. As it moves over the warm waters of the Indian Ocean, expect strengthening. With strengthening, comes a signal for the mid latitudes. This is expected to set up -PNA (Trof over the far west) and Ridge in the east, further delaying Winter for the east with a stormy period out west. This is expected later week 2, (2nd half of next week), through the following week) (so about the 20th through the 29th).
Expect odds for moisture leaden storms to increase for the west coast later week 2 through most of the remainder of November.
More Later……
Dr Howard and the Dweebs………………..:-)
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Of note, it has been below freezing in Mammoth for the last 24 hours. Snowfall will wind-down today with possibly a few more inches to add to the 12 inches that has accumulated at the Main Lodge the past 36 hours. The air is clean and fresh! Just the way we like it! The Cold Low is currently sliding SSW and will back door us today. Dynamically, the main focus will be the Southern Sierra south to Southern CA for precipitation today….Highs today will be in the mid 20s with a bone chilling 4 degrees expected by Monday Morning. Currently, Snowfall amounts on Mammoth Mt are within forecast, (10 to 15) inches. A few more inches may fall mainly this AM with just some light snowshowers the remainder of the day.
The Storm, (Pattern Wise) that brought snowfall to our region is classic in a La Nina Winter. Cold Great Basin Long Wave trof with energy entering CA from a short distance off the west coast. This pattern is cold with usually light to moderate snowfall with any individual storm (Short Wave)……
Outlook:
The next weather system appears to have an small AR connected to it….That would be next Friday.
WX Pattern:
The Pattern later next week as shown in the 5 day means, 500mb heights, shifts the current long wave now over the Great Basin and Inter mountain westward, well off shore. The upper jet relative to CA has currently little over water trajectory, however, is strong dynamically with lots of cold air aloft.
Again…The day 5 means shows the long wave trough retrograding over the next 5 to 7 days. There is deamplifacation in the process where-by an almost zonal upper jet develops with lots of over water trajectory from the North Pacific to the Northern and Central CA Coast. The longwave shifts westward to around 125 to 130 west. The upper jet also lifts northward up into the Pacific NW.
There has been an atmospheric river of modest intensity shown in the models the past few days for next Friday. The storm and pattern later next week is one of mainly warm air advection, whereby moisture coming in from the pacific is being lifted over the existing cold surface, like what we have at the moment over California. There is not much in the way of any dynamics (vertical motion) from a pattern like this. However, the forecasted winds at 700MB along with significant moisture advection can produce a fair amount of precipitation, well south of the anticipated upper jet position. Snow levels will undoubtedly rise….Possibly up to 8,000 or 9000 feet.
This is what we need at this time of the year, good old fashion Sierra Cement, not cold dry powder, like what we just received!
I see more storms later in the month…..November looks Marvelous and setting up December for the holidays…………….
Dr Howard and the Dweebs……………….:-)