9:20am Thursday:

 

Back edge of the AR has moved through the Bay Area and progressing east.  As of 8:00AM, Mammoth Pass has picked up 3.5 inches of water EQ with another 3 inches in the bucket expected over the next 24 hours.

Colder storm off the coast of the pacific NW is digging SE and becoming negative tilt. It has picked up the southern stream trof and is the kicker that will bring in its remains tonight…The current AR is now pushing into Southern CA increasing rainfall rates there.

By early Friday AM a dry slot comes through, diminishing cloudiness and gives us a pretty nice Friday afternoon except for wind. The upstream cold core kicker trof will open and come through Northern CA Saturday night. Ahead of it will be light snowfall for our area. Amounts look lighter than my previous post. RFC has backed off and now reports .59 inches of QPF for Yosemite. Even at 15:1 that would be about  9 inches over the crest. Best guess for the Saturday storm….2 to 4 inches at 8000 feet and 4 to 7 inches over the upper elevations by late Sunday AM. Snow showers may persist for a while into Sunday afternoon but little if any accumulation is expected Sunday PM.

Longer Range shows ridging building in Mid-Week with Gusty Easterly Winds over the Mammoth Crest Tuesday into Wednesday with quite a bit of warming Wednesday into Thursday. It looks dry and warmer Tuesday through the following weekend.

 

It will be cold over the weekend with highs in the low to mid 30s in town and lows in the single digit and teens across the county.

 

The next possible stormy period will be beginning about April 5th or 6th….

 

Dr Howard and the Dweebs……………….:-)

 

 

 

 

9:30Am update

New guidance from the California Rivers Forecast Center shows the freezing level dropping quickly Thursday morning and that precipitation will be all snow to the lower elevations of town by Noon Thursday. If this is true then heavy snowfall can be expected to all elevations of Town Thursday afternoon.  The same forecast shows between 5 and 6 inches of water EQ over Mammoth Pass between today and by Thursday night. This is in addition to the nearly an inch that has fallen so far.

Other changes; Moderate storm Saturday with up to a foot of light powder on Mammoth Mt and some 3 to 6 inches of snow in the Town of Mammoth as the freezing level lowers to 3000 feet Saturday. Light snow showers are now expected Sunday. Dry Monday…milder Tuesday….

Friday looks dry…..

The snow level in the Mammoth area will be mainly 8000 to 8500 today and up to 9000 feet for a time tonight. The snow level will come down during the day on Thursday and into Thursday night. The snow level will lower to between 6500 and 7000 by Thursday night.

 

Change in weekend forecast;

The models have been consistent since yesterday in deepening the northern stream trough enough to bring light snowfall to our area now….Saturday and into Sunday. Expect much colder temperatures over the weekend.

Next week look dry and milder at the moment.

 

Dr Howard nd the Dweebs………………:-)

 

 

 

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Tuesday AM:

Here is the latest…..

In summery…There is a lot of moisture coming to all of the sierra

In the Town of Mammoth there could be between two and 3 inches of water equivalent.

Over the lower elevations of town (7500 ft)  I am not expecting a lot of snowfall. It will be mostly rain or rain snow mix. It may start as snow but will change to rain pretty quickly as the AR rushes in Wednesday so not much accumulation.

At elevations “Between 7500 and 8000” there could be up to a foot of sloppy wet snow.

At elevations between 8000 and 8500 there may be somewhere between 1 to 3 feet of wet snow. It is very difficult to tell whether it will be a 1.5 feet or 3 feet. You are only talking about a temperature difference of maybe 1 degree.

The main snowfall with this storm will be above 8500 feet where 3 to 6 feet is possible. The 5 to 6 feet is above 10,000 feet. (Sierra Crest)

The not so good news is that there is a large dry slot coming in behind this storm Friday and that will cut the moisture off pretty quickly Friday. So….not much influence is expected from the northern storm for Friday into Saturday night with only light snowfall expected.

What we have here in Mammoth is a weather pattern that is primarily an Atmospheric River with not much follow though with moisture from the northern branch.

It will be wet and wild the next few days!

 

Temperatures will be in the low to mid 40s today and mid 30s tonight…then highs in the upper 30s on Wednesday and mid 30s Wednesday night with little change in temperature for Thursday. I am expecting a freeze by Friday Morning with lows in the 20s.

 

Saturday there is a chance of snow showers and it looks to be a Blue Bird Day on Sunday..

 

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

 

 

 

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The First major Atmospheric River event this year is shaping for Southern CA and the Southern and Central Sierra, for Mid-week. A wide swath of rich Precipitable Water will stream into Southern and Central CA beginning Tuesday night and will increase in its intensity Wednesday into Thursday. this is part of an Omega Block over the Central pacific and the eastern portion with its cut off low spinning at 140west and some 1000 west of the central coast tonight.  The Duration of the event along with its intensity suggest that orographically favored areas on the west side of the southern sierra could get up to 10 inches of water from this storm. Here in the Eastern Sierra, the west side will take the brunt of the storm, squeezing some 5 to 7 inches of water over the Mammoth Crest for a good 5+ feet of snow.  Snowfall amounts in town will vary greatly where the Mammoth Slopes area above 8000 feet will get a lot of snow through the period ending Saturday while the lower elevations of town get a lot of rain at times and not as much snow. So at times it will rain and at times it will snow at 7500 to 8000 feet.  The Nested Grid model shows the snow level lowering into town by Thursday morning….This is Faster than predicted on Sunday Morning. We still have another 24 hours to follow its progress, as the storm is still developing…. By Thursday night, the AR should be south of the state while the colder portion of the pattern with its cold GOA low digs south into Northern CA. This will bring colder lighter snowfall to the high country, Friday and especially Friday night into Saturday.

 

 

Dr Howard and the Dweebs………………….:-)