Winter Storm Warnings Have been hoisted by the NWS beginning 7:00PM Tuesday through 7:00PM Thursday…..Winter Storm will move out Friday…..

11:45pm Sunday

Quick look at the 00z Mon Euro shows a slight jog of the upper low toward the coast.  It also stalls it out near the Bay Area Thursday morning into the early afternoon.  A little better…..

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Latest Guidance shows a powerful winter storm headed for the Sierra Tuesday night and should continue through Thursday.  Because of the dry cold front that will move through on Monday, bringing breezy weather and colder temperatures, The Tuesday night storm will begin as snow for the entire Mono County area. Snowfall amounts of 5 to 10 inches will be common along the highway 395 corridor with 10 to 24 inches west of Highway 395 and between 2 and 3 feet now expected over the higher elevations of the Sierra.  The QPF for this Storm for Mammoth MT is between 2 and 2.5 inches.  Because the temperatures are so cold, the snow to water ratios will be much higher than normal, with some areas like Mammoth Mt receiving between 2 and 3 feet by Thursday night. The bulk of the snowfall will occur Tuesday night through Wednesday night.  The Town and Village at Mammoth is likely to receive between 10 and 20 inches.

Here is the temperature forecast for Mammoth this week…

Monday   Tuesday   Wednesday   Thursday    Friday     Saturday

42/14        36/19       23 /12           23/7          22/6         28

The main change in the storm for this upcoming week is that it will not linger off shore as long. There is a bit more over land track. The upper low that forms off the OR coast spins up Tuesday night and moves onshore Wednesday as heights continue to fall down the coast. In that the trofs axis remains mainly along the coast, there is plenty of over water trajectory for the storm and will hammer the Sierra well!  Again the center of the storm does not become cut off and drift south. As a result, its more progressive nature allows the storm to kick out about a day sooner.  This will limit to some extent, the long period of heavy rainfall that was forecasted for the LA basin, earlier in the week.  LA will get a good shot of rain, however, 2 to 3 inch amounts over the LA Basin are unlikely. Although, those amounts my occur for the traverse ranges.

Monday’s dry cold front dropping south through the Great Basin will dump a lot of cold air upon the Owens Valley Floor.  This sets the stage for snow not rain, for the following pacific storm Tuesday night and Wednesday.

For the Owens Valley, the more inland trajectory of the 2nd system will possibly take “some” of the punch out of the precip forecasted Tuesday night through Thursday night. There was a plume of moisture that was lurking off the coast of Baja, that will now shift east rather than get pulled up into the Inyo County area. Again, this is because of the slight change in the pattern of the more inland path of the upper low. However, make no mistake about it, there is the potential for some 5 to 10 inches of snow for the Valley, which is plenty to create problems for holiday travelers.  At the Moment, there is currently a Winter Storm Watch out for the Owners Valley. The watch remains as there is some uncertainty about how much snow will fall.  Travelers should click on the following link Monday, to see if a warning is issues by the NWS.   SEE:  https://forecast.weather.gov/MapClick.php?zoneid=CAZ520

Longer Range:

  1. There may be another storm the Following Monday.
  2. Subsequent storms are expected to have more over water trajectory and be wetter.
  3. In some of the Euro runs, an AR is showing up for around the 7th of Dec.
  4. The warm water pool that everyone was worried about off the California Coast last September, moved west some 2000 miles. This actually is supporting storminess for the state, not hindering it.

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

 

 

 

 

Chilly weather to give way to a milder weekend…..Then Ready-Set-Go for Snow!!

 

11-24

 

 

I will be posting this afternoon…

 

just a quick note to say that the storm looks very good.  Although it may lift out more like Friday instead of Saturday….

 

It still looks like at least 1 to 2 feet and possibly more on the mountain by the next weekend.

Prime time is Tuesday night into Wednesday.   Snow for the Owens Valley Wednesday and Thursday…..as much as 5 to 10 inches in some places.

 

Dr Howard and the Dweebs…….

 

 

 

 

 

 

 

10:00am

 

quick comparison of 12z run to 00z shows some shift of the upper low a bit inland in its track. Some height rises on back side of digging trof.  Will have to follow this change to see if it shows up in future runs….

 

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Saturday Am

Note for holiday travel to the high country

Travelers to the high country via the Owens Valley will want to pay very close attention to the Weather and Road conditions  for Wednesday. This storm with its very cold temperatures and the fact that it will remain along the coast some what cut off is setting up a rather long period of upper difluence over the southern half of the state. This looks like a classic snow pattern for the Owens Valley.  1000-500mb thicknesses suggest a snow level of between 3000 and 4000 feet.

So temperatures will be cold enough for snow on the Owens valley floor early Wednesday into Thursday.

The storm is still a good 3+ days away and the timing still being worked out. However this type of storm suggests that travelers begin their travel with an especially early start to the high country. Tuesday would be better for travelers.

Please keep close tabs on the forecasts from the national weather service over the next 5 days and prior to departure, check road conditions from Cal trans.

The Dweeber……..

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8:30AM 11-22-2019

Last nights Euro and GFS are consistent with previous runs, with the placement of the upper trof. Differences show up in the Run to Run height field with a lowering heights in the back of the trof. This suggests more digging and the ability for the storm to remain off shore longer.  The Euro shows “possibly” some bombing. Not sure if it meet that criteria, with the surface low west of Pt Arena going from 1003 mb to 975mb within a short period of time. Needless to say the storm has the potential to bring some strong winds to areas.   I think that at least for this period time, the EC has a better handle on the pressure field as compared to the GFS as the GFS has come into more agreement with its 06z run. The emphasis is going to be on the cold and snow for most areas of the eastern sierra by Mid Week, including  parts of the Owens Valley….  The Storm will eventually move in over LA and provide up slope to the Eastern Sierra next weekend…  In that the storm taps some moisture from North of Hawaii, the QPF still looks very good, in the 1 to 2 foot range for the upper elevations, but no doubt will be updated in the coming days…

The Sierra, north to south will do very well from this weather system…..

 

There is another weather system following by the very end of the holiday weekend that will be more of a cold inside slider….Stay tuned on that one as well

 

Stay Tuned,,,the Dweebs got you covered…..

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8:50PM Thursday the 21st…..

I thought I would post again today…this evening.

I looked at the new GFS 00Z Friday and the Trof axis is very very close to the west coast. It stays there for several days. I am waiting to see if we get a closed low that spins up Tuesday night that heads south down the coast and wallops LA with soaking rains like the EC showed this AM.  I am awaiting the 00z Friday Euro and I will update in the morning before 9:00AM.  But now to the good news….

The new 00Z Dec 21st ECMWF weeklies, that go through December, have updated and the ensembles show more and more over water trajectory of wetter storms for the Sierra as we get on in the month of December.  This is great news.  What I really like is the 7 Day ensembles means in the weeklies during the 2nd half of December.  The Negative Height anomaly is over the far west!

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It never ceases to amaze me how quickly the weather can turn, not only here is the eastern sierra but over the western hemisphere. This time a massive ridge of high pressure develops over the north pacific at around 150 west Tuesday. Our ridge off shore retrogrades and joins up with a large short wave ridge currently coming off Asia. The two meet next Tuesday and amplify north,  while a massive thrust of modified Arctic air pours out of Eastern AK and Western Canada. The redevelopment of the subject ridge provides a direct pathway of very cold air down the west coast. Just off shore…Rapid Cyclogenesis is possible Tuesday evening.  The system then slows and parks itself along the west coast for two days!   700MB temps are -12 to -13 Tuesday night, cold enough to brings snow to even the lowest valleys of Mono County! Amounts of snow fall at this distance in time still in question. However, considering the snow to water ratios…some 1 to 2 feet would not be out of the question for Mammoth Mt. This will be fined tuned later. The GFS has a bit more over water trajectory so it would tend to be a little wetter.

 

I would still prefer a wet storm of sierra cement for this period, but will take what we can get.   The storm looks to last for two days….  Beginning Tuesday night….

At this time, the Southern and Central Sierra look to receive the heaviest amounts. LA will get some heavy rains as well.

This may bring significant travel issues for the Sierra for early holiday travelers…because of the powdery snowfall and the likelihood of a period of blizzard conditions …..

 

Stay Tuned….

 

 

In a flash…the Warmth of Fall is Gone….New weather Types Await the Eastern Sierra……..

It was just two days ago, our highs were in the upper 60 and today upper 20s..   That’s pretty remarkable and difference in 40 degrees of cooling over two days….   Our closed low that brought us rain and snow showers to town yesterday afternoon has moved inland and located over Kern County. it will meander in the same areas today before moving over southern NV later Thursday AM. The Rapid Refresh model brings some .25 to .5 inches of QPF to our area, Mainly this evening. So expect a better chance of snowfall accumulations this evening. (2 to 5 inches)

After a chilly day Friday, expect a fair and cool weekend with high climbing to the upper 40s by Sunday.  Thereafter it will grow cooler Monday and Tuesday as a NW slider pushes drier cooler air into our area from the Pacific NW.  Night time temps will be in the 20s, then teens early next week in the drier air.  Snow making is full on now on Mammoth Mtn.

The comments from the CPC were well taken yesterday. Again they are looking at the possibility of a cold western trough late this month and into December. Exactly where it sets up will be key. This is an even colder weather pattern than what we have now.   The storm track will retrograde a bit around the Thanksgiving holiday. That means that there may be more over water trajectory and a better chance of accumulating snowfall.  However the main emphasis is going to be the cold that will be headed our way toward the end of the month.  Both the Euro and the GFS still have their differences and a difference of only 100 miles will be a big deal on how much snow we get from the changing weather system. Further retrogression of the western trough is expected in December…..

This month….These systems will still spin up off the west coast and drop south over California. That is usually not a great pattern for snowfall, but again, a little more of an off shore track would make a big difference. December looks much better!

 

I will have the EURO’s long range outlook update this Friday for snowfall in December…..

 

Dr Howard and the Dweebs………….:-)