Archive for October, 2014

Sunday AM

Total Precipitation 1.72 as reported by the Sesame site…..13 inches of base.

The Upper Mountain which was colder probably had about 18 inches up in the Bowls…..

Early morning low here at Mammothweather was 16 degrees this morning and it was 31 at 10:00AM

With long wave ridging setting up over the far eastern pacific, a warming trend will kick in Tuesday with high temps back into the 60s later this week.

It looks dry the next week and possibly two….

The Dweeber…..

Saturday AM Update.  10:00AM

Mammoth Mtn at the base lodge is showing 12+ inches of snow past 24 hours with 1.54 inches of water. That is about 7.75:1. IE heavy base building sierra cement!  The freezing level took its good sweet time in coming down and so we have not received the accumulations expected in town, but the QPF has verified. For those checking Mammothweather.coms Snowmelt system data, the Dweeb pulled a Nerd and forgot to flip on the snow heater until 8:30am this morning. So the snow in the bucket is still melting and will tally up the precip over the next several hours….  The good news is that heater is now on for the winter!

Expect the currently light snowfall to diminish to showers now, as the base of the upper Trof currently moving through the San Joaquin Valley exits the area tonight. The Dweebs do not expect more than another one or two inches at the most today in town. Temperatures: High today 38f -Low 18f – high Sunday 40f.

Some thoughts for the Day:

Most Falls patterns begin with inside sliders that generate a Cold Showery pattern for the Eastern Sierra and Santana conditions for Southern CA.   So during this Fall we actually began with a moderate storm from the NW that will end up bringing up to 1.75 inches of water to the crest.  What does that mean?….Probably nothing. However, I think that we still need to go through that inside slider pattern typical of Fall to get to winter.

Beginning after mid month, I expect to see major amplification out over the eastern pacific with a full latitude ridge building between 145 to 140w and a cold system that drops NNW to SSE into the Great Basin. The actual trajectory will determine if there is snow in it for us. IE Whether it is off or on shore.  We usually see this kind of pattern as we get into December. As mentioned earlier in a discussion, there will be some significant cold outbreaks later this month and especially during first half of December. When will this begin?  Just after Mid November I believe.

SSTA’s

There is still a lot of warm water typical of the +PDO that extends all up the west coast.  The water is warmer than normal to a lesser degree in the Gulf of AK. We will have to watch the cold water pool that has been extending eastward for the western pacific to see if some of that mixes into the gulf later this year. If the Warm Pool along the west coast that extends up into the Gulf of Ak is a persistent feature, that could form a block along the west coast and provide for a persistent path for Arctic Air into the nations mid section…especially with the -AO and -NAO forecasted this winter.  In that case we’ll really need the help of the subtropical jet to over power that block.

More Later……

Dr Howard and the Dweebs………………………:-)

5:30PM Friday Update:

Latest SFO Radar shows the main band of precipitation enhancing as it approaches Merced CA. However, it will still be about 4 hours before the leading portion of that gets into Mammoth Lakes.   However, the 23Z NCEP HRRR 3 kilometer model shows some light shower activity currently occurring now on the west side. That could slop over anytime after 6:30PM.  Showers from that area of clouds should increase over the Sierra Crest over the following hours, gradually pushing off to the east.  The main band is expected to push precipitation to a point East of Highway 395 by 10:00 to 11:00PM. Heaviest snowfall rates will begin about Midnight into the morning hours….

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The Various QPF model forecasts continue their trend of ramping up snowfall estimates for our area over the past 24 to 36 hours.  Furthermore…..Model runs continue to be very consistent in the storm’s track. The cold air in this system by most winter storm standards is average with a large -25C Isotherm on the back side of the upper low at 500MB and -5C at 700MB. Certainly not platinum powder standards, but a good wholesome sierra base building system. CRFC has increased their QPF for Yosemite and Huntington Lake to about 1.55 inches. Historically, with this type of storm, Mammoth Pass can get about 2.00 inches of water. So the Dweebs best guess is that the Sierra Crest will see between 18 to 22 inches at about a 10:1 Ratio as an average.  We’ll see how that works out by the time the storm is over by Saturday night.  This is certainly a good start and especially for the Southern Sierra which will benefit the best from this storm.  As of 9:30am this morning the latest (15Z) run of the high Res HRRR showed precipitation just beginning to slop over the crest at between 7:00 and 8:00PM tonight. So there should be plenty of time for the Trick or Treaters to get their job done if they start early. Thereafter, snowfall rates ramp up quickly after 9:00PM with Moderate to Heavy snowfall by 06Z Saturday.

Longer Range Outlook trends drier the first half of November then wet the second half…..

Dr Howard and the Dweebs…………………….:-)

Wednesday AM Update:

1. Splitting Trof off the pacific northwest Thursday night will shift most energy into Mono County Southward.  Even Los Angelus will get rain now from this storm. Snowfall in the high country will average a foot over the crest with 3 to 6 inches for the Towns of Mammoth and June. Friday will be increasingly windy with gusts to 45 MPH in the Town of Mammoth so for the trick or treater’s…..get it done early!!

For Today and Thursday…slightly warmer temps can be expected with highs in the mid to upper 60s…..Lows in the 30s

Tuesday PM Update:

The Dweebs took a look at the latest QPF from NCEP/WPC and noted that Mono County was in for about 1/2 inch of QPF.  It also indicated that the Northern Sierra would fair better with over an inch of precip. I looked that both the 00z EC’s QPF over the weekend and the 18ZGFS.

NCEP/WPC must be looking at and using the EC for its guidance. However at this distance in time, the GFS is probably better with at least an inch of QPF for Mono County over the Crest.  The latest guidance is splitting the Trof as in comes inland with more of the energy diving into Mono County than the Northern Sierra. The net effects would be to slow the system down and begin the precipitation later in the day Friday and delay the main precipitation until later that night of Halloween. By Sunrise Saturday, the bulk of the snowfall will be over, with a cold showery snowfall pattern continuing throughout the day.  It will be cold Saturday with highs in the 30s….  How Rude!    Expect gusty winds of 30 to 40 MPH at times…nothing unusual for Mammoth Lakes Friday.

Dr Howard and the Dweebs………………………………..:-)

Monday AM:

Slow warming trend underway as some flat ridging takes place. Thursday will be the warmest day with highs in the mid 60s in Mammoth before the 1st good storm moves in Friday afternoon. Great news today as although no official El Nino declared by NCEP because they use the ENSO 3.4 region as a guide, a couple of the indices are ready touting it.  Of Note: The SOI; Southern Oscillation Index Value from Queensland, AU for the last  90 days  is -8.3. Daily Contribution -10.6.  This along with the MEI says we are already there…..That weak El Nino conditions are under way.

New 12z Monday GFSX and 00Z Monday ECMWF are similar that over the next two weeks a series of significant storms are headed for Central and Northern CA….

Longer Range:

It all good……

Todays NCEP CFSv2 from has The Mammoth Lakes region’s Precipitation at a 250% Deviation from Normal with 8.5 inches of water EQ by November 30th.  If that verifies….At 10:1, 85 inches of snow by months end over the upper elevations.

Dec:

Mammoths Precipitation as a deviation of normal from December 1st through the 10th is 150% of normal.

Additionally…the model shows an additional 1.5 inches of water the first 10 days of December for a total of about 9.5 inches of water over the next 45 days. That would be 8 feet of snow the way it falls over the upper elevations….If it works out.

More Later…………………………

The Dweeber………………….:-)