Archive for January, 2018

Storm System Exits Southern California with death and distruction in its wake…High pressure to build over the state in the coming days leading to a fair weekend….Surface cyclogenesis off the coast of Japan next Wednesday suggests a wet following weekend….

I will begin this morning with the end of my last post with this;

 

Outlook: From January 9th.

Although the Dweebs have not seen the latest ECMWF model, the latest 12Z Tuesday GFS has the upper jet moving back into Northern California early next week where it keeps it there for several days. The Upper Jet sags south towards us, during the second half of next week. (Using the Japanese surface cyclogenesis method), as a timing tool used by Hovmuller, it shows a rapidly deepening surface low that is “bombing” off the coast of Japan the next Wednesday. That energy is expected to come through our area about Sunday the 21st. So, based upon this theory, the following weekend should be wet. (Again, I have not seen the latest EURO as it has not run yet) I will update later today….

Wednesday 10th 4:55AM

We have now become familiar with the term bombing. In meteorology, the term does not refer to some terrorists act. It refers to a rapidly deepening surface system over the ocean. It can happen geographically in the high to mid latitudes, over many areas of the globe in both hemispheres.

There are two terms that represent rapidly falling surface pressure and cyclogenesis over a period of time.

  1. Bombing or Bombing Out or bombogenesis is a term used when surface pressure at 60 degrees north latitude falls at a rate of at least 24 Millibars in 24 hours. This causes explosive development or rapid cyclogenesis.
  2. On November 10th, 2014, remnants of Super Typhoon Nuri caused surface pressures to fall 50 Millibars in 24 hours. The depth of that Bomb Cyclone reached an estimated 924 Millabars. I believe that this was more then enough for a case of “Super Bombing”?
  3. On another note, the Cyclone Bombing that traditionally occurs off the coast of Japan, occurs when cold Siberian air clashes with a disturbance in the westerlies over the warm waters of the western pacific. Rapid Bombogenesis occurs several times a year in this region.
  4. The late Meteorologist Ernest Hovmöller (1912–2008) discovered many useful tools that involved timing.  As an example, the Hovmöller diagram is a very useful tool for determining the speed of various atmospheric disturbances, as it contours a variable in both time and space.
  5. The Dweebs use Hovmoller’s western pacific Bombogenesis tool to help predict the propagation of energy across the pacific for the timing of short wave energy, that transits across the west coast. It is not 100% but is quite useful in determining whether the global models are being accurate in their timing.

Last nights ECMWF has the timing of the surface cyclogenesis like yesterday’s GFS, next Wednesday as well. So the propagated energy should come though sometime about Sunday the 22nd.  Moisture and precipitation will precede the energy, several days ahead. So expect precipitation to begin about Thursday or Friday next week (will fine tune timing later) into the weekend of the 20th. Note: Although this particular cyclone development may not be a “Bombing Cyclone”, the energy non the less will propagate across the pacific.

 

Dr Howard and the Dweebs…………………:-)

 

Storm System decide to pay visit to “Sunny Southern California” dumping heavy rain, while only moderate amounts of snowfall have fallen over the upper elevations of the Eastern Sierra….Mammoth Mt reporting up to 18 inches over the higher elevations this morning……Expect a mostly sunny weekend with possibility of another storm after Mid Week next week….

It is always a disappointment when we do not reach winter storm criteria in town, but 18 inches over the upper elevations and possibly more to come today is certainly encouraging!  Results; The GFS had it further south and so it was the correct model to follow….Go figure!  A difference of 50 to 75 miles was all it took.  In the meantime, our winter storm warning has been dropped to a winter weather advisory due to slippery roads, mainly above 7000-7500 feet.  Latest rapid refresh model shows 1 to 3 inches in town with some 3 to 6 inches possible on Mammoth Mt through tonight. There maybe be a short period of Wrap-Around as the upper low moves through to the south of us. Although we did not do as well as we hoped for, we did a lot better than many of our neighboring ski resorts in the Northern Sierra!

Wednesday will be a day of improving weather with skies yielding a few early morning showers. Sky’s will become partly cloudy during the day then clear out Wednesday night. High temps will rise to the 40s Wednesday. The weekend weather will be fair with calm winds.  Expect an increase of upper elevation breeze Monday afternoon into Tuesday next week.  Lows over the weekend will be in the 20s with highs in the low 50s.

Outlook:  Although the Dweebs have not seen the latest ECMWF model, the latest 12Z Tuesday GFS has the upper jet moving back into Northern California early next week where it keeps it there for several days. The Upper Jet sags south towards us, during the second half of next week.  (Using the Japanese surface cyclogenesis method), as a timing tool used by Hovmuller, it shows a rapidly deepening surface low that is “bombing” off the coast of Japan the next Wednesday.  That energy is expected to come through our area about Sunday the 21st. So, based upon this theory, the following weekend should be wet.   (Again, I have not seen the latest EURO as it has not run yet) I will update later today….

 

Dr Howard and the Dweebs….

While the Eastern Sierra Experiences it first Dusting this Morning….More important changes on the Horizon lead to Weather Optimism for the Month of January…

 

Monday 7:00am

WSW now in effect

note:  snow level will rise today to between 8000 and 8500 then come down later this afternoon and tonight.

 

All model simulations have a track of the upper low moving west to east between Santa Barbara and Lax. This is further south than predictions Saturday. Main focus of forcing will be Southern Sierra with extension north to about Mammoth. Heaviest Precipitation will be coastal mountains of Ventura Co and eastward with local amounts 7 to 9 inches of water.

Mammoth Mt stands to receive 3 to 4 feet over the crest with 18 to 30 inches in town above 8000 feet by Tuesday night. 15 to 24 inches at 7500. Expect a fair weekend with high pressure aloft.

Dr Howard and the Dweebs……

 

Complete update Tuesday morning…

 

Sunday pm update

 

Winter storm warning:

http://forecast.weather.gov/showsigwx.php?warnzone=CAZ073&warncounty=CAC051&firewxzone=CAZ273&local_place1=13%20Miles%20E%20Lee%20Vining%20CA&product1=Winter+Storm+Warning&lat=37.939&lon=-118.887

 

300pm sat update

 

A winter storm watch has been issued by the national weather service for elevations above 7500 feet beginning at 7:00pm Monday night and continuing through Tuesday night. Between 2 and 3 feet of snow is expected by Tuesday night.

Amounts over the crest are expected to be 4 feet+.  There will be a break next weekend before the “first” powerful jetstream of the winter of 2017/18 arrives about the 15th…

 

I will have a detailed update in AM

 

 

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Finally…cooler breezy weather has returned to the high county this morning with a dusting of snow over the higher elevation’s and more to come over the next 5 to 7 days. Our dominant west coast high pressure system has shifted east to the state of Utah this morning. That’s enough to open the door to some pacific moisture and cooler temperatures.  The wave that moved though early this morning brought a few hundreds of an inch of water EQ. Another wave will move though Friday night with up to .30 inches of water over the crest. This should bring some 2 to 4 inches of snow over the top of Mammoth Mt. High temps will be in the 40s in town with lows in the upper 20s to low 30s

Extended:

A more important system that has been well advertised will move into the high country early next week with the potential to bring between 1 to 2 feet of snow over the higher elevations by Wednesday afternoon. The storm is being handled differently by both preferred global models. The ECMWF (EURO)  has the system coming in as an open trof while the GFS has it coming in as a large closed low. Either way, Mammoth gets good snowfall but the EC would be wetter as it can transport more moisture into the system while the GFS has us in the NE quad of the closed low system. The GFS  closed nature favors good lift, however, does not have as much moisture potential as the EC.   In that the EC has ensemble members that are more numerous with its solution, the Dweebs are favoring the EC at this time. IE more precip. Stay tuned on this Monday through Wednesday system for next week.  PS. it will be a colder system as well.

Long Range:

Another pattern change favors more of a zonal flow about mid month.  This is associated with quite the potent Pacific Jet Stream. I am suspect at this time of this wet scenario.  This pattern would be A-Typical due to the nature of a winter that has been associated with mostly Meridional flow thus far.

 

Dr Howard and the Dweebs………………:-)