Northwest Flow to Continue with another Small Breezy System Friday then warmer the end of the week into next….

The Eastern Pacific ridge out some 1200 miles off shore along with the Western Atlantic Ridge off the East coast is keeping Arctic Air intrenched in the nations mid section. Below Zero temperature’s are common throughout much of the the mid west and Great Lakes States…. This is a pattern that will last more often than not the next week. This effectively keeps the door closed to the pacific as the upper jet is more over the Great Basin and California, with mostly an over land trajectory in a northwest flow. It is a particularly windy pattern. The next upstream system is no exception with light amounts of snowfall similar to the Monday system expected for Friday night.  High temps to remain in the 30s and 40s the next 5 days with lows in the teens and 20s….then a jump to the 50s expected by next Monday.  The next significant storm cycle looks to begin the end of the month with the Patten possibly staying active, much of the month of March…..

 

Dr Howard and the Dweebs……………..:-)

UGLY NW Jet Approaching Central CA Saturday…Its a powerhouse….Some areas may have damaging winds on Saturday…..Another is in the works for possibly Monday night and Tuesday……

High WInd Warning was issues by the National Weather Service beginning at 6:00AM Saturday to 4:00PM Saturday

Stay in Touch with the advisories from the National Weather Service as they will be watching this developing situation through out the night tonight….

 

Today’s model trends show a very Nasty 160 knot NW jet that will be moving in later tonight and affecting our area through Saturday evening. The emphasis is wind with light amounts of snowfall. Another windy and potentially just as strong a system will move into our area Monday evening with high winds into Tuesday.    The Pattern is the very ugly and strong NW jet.  This is the pattern where we get our strongest winds. Both the Saturday and the Monday night system will bring light amounts of snowfall. in the 1 to 6 inch range.  The Communities along Highways 395 like Crowley Lake may have winds in the 80 to100mph range or stronger….

Winds aloft in our area are expected to be 50 Knots at 700MB/Double that for an estimation of winds on the top of Mammoth mountain (100Knots). Then to estimate surface winds along eastern slopes divide by 2/3rds… So winds are expected around 67 knots at the surface. (77 MPH)  Gusts are possible to 88 or 90MPH.  Of course this is just a guide.  Terrain enhancement’s can really come into play with stronger winds in some areas.

Looking at the Rapid Refresh Model for mid morning Saturday, the winds are pretty strong From Mammoth South along 395  to Wheeler Crest with another strong area of strong winds near Fort Independence.

 

Dr Howard the the Dweebs……………………:-)

Bias Toward Undercutting is increasing next week as models trend wetter…..Model Consensus not strong yet…….

Monday AM:

There looks to be two periods of significant precipitation. Thursday night into Friday AM and Saturday Night into Sunday.  The Dweebs do not have a lot of confidence in amounts yet.  The Experts at CRFC gave the west side near Huntington Lake close to 3.00 of water between Thursday and Sunday AM…..That’s pretty bullish. The first storm for Thursday night is fairly warm with the freezing level at 8000feet. It lowers to 6000 feet by Friday.  That is not the snow level, but the freezing level. So it will be wet heavy snow for the town and using the CRFC QPF, about a foot on the mountain. There are two periods of weak AR taps. One Thursday night and again Saturday night.

The Saturday night storm is colder with the freezing level lowering to 6000ft so better accumulation in town.

In the longer range, the GFS had a stronger AR progged for the middle of next week. There is little or no confidence in that run at this time.

My take on all this is that;

  1. The models will eventually get  better handle on the pattern by this mid week.
  2. It may end up being that the more important storms will wait until next week….As the pattern evolves.

 

The Dweeber…………………:-)

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The Dweebs have been watching for the next pattern change for Central CA. There is one developing next week.  However, there is little clarity whether the change offers a period of major storms. The European model is much more bullish on the upcoming pattern change being one of which is wet……The GFS is drier.

Esoteric comments:

  1. Looking first at tropical forcing, the MJO is still being affected by La Nina. La Nina’s destructive interference with he MJO has blocked the successful propagation of the MJO and other modes of tropical variability, beyond the Western Pacific.  However,  the biggest evolution in the relationship between the North American mid latitude circulation and tropical forcing appears to be the relationship between the MJO/ER/KV  and the calendar, as shown in the MJO lagged composites.
  2. The ECMWF appears to be the winner as it seems to be more in agreement with the idea of undercutting as indicated in the MJO composites, specifically with phase space 7 of the Wheeler and Hedon’s,RMM1 and RMM2.

SEE:  Location of the MJO is phase space 7 SEE:  https://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/foregfs.shtml  ; then (Composite for February in phase 7)   (Plug in the phase space and time of the year) https://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/LaggedComposites

3. With all discussed above, I have to say that although there is clearly undercutting shown in the composites for the lags 2 and 3 which coincides with the phase space, none of the other height anomalies coincide. So if the composites verify, would it not be for all the wrong reasons?

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Todays Global model guidance simply shows that both GFS and ECMWF has differences in how they handle the cold Trof in the east with its Arctic air.  Currently all models are in agreement that the pattern is blocked out west due to the massive Polar Vortices’ that extends from the extreme NW territories of Canada to just north of the Great Lakes. The massive negative height anomaly has been responsible for the big freeze in the Mid West and the heavy rains in the south and southeast.  The progs Weaken this Upper low as it retreats up into Canada as becomes more east west orientated.  The biggest differences in the models is how much remains of the low south of 50 North, as the more of it that remains south, the weaker the undercutting will be into the west coast.  All of this will be resolved within the next 3 days…..

Stay Tuned….