Warm-up this weekend will mark the first stretch of 70s in Mammoth this year as Spring comes to a close over the next few weeks and the longest days of the year approach…..

As we approach the Summer solstice over the next 3 weeks the upper jet will continue to weaken and spend a great deal of time to the north of us. This weekend will be highlighted by high temperatures some 10 degrees above normal with mid to upper 70s expected by Sunday. This upper ridge will give way to lower heights later next week for some cooling. However, temperatures are expected to remain in the low to mid 70s through mid-week.  There will be more Zephyr wind next week as the west to east gradient’s increase. Further out, high pressure builds over Texas and this pattern generally gives Mammoth more south-west flow. This should continue the dry pattern of late.

 

Longer range does show climatically favored upper Trof, bringing wind, cooling with possible showers toward Fathers Day, (sometime during 3rd week of June). Whether this actually plays out, only time will tell.  In the meantime, “Script from George Harrison”; Little darling, it been a long-long cold winter, “Here comes the Sun”…….:-)

 

High temperature’s in Mammoth today Saturday and tomorrow Sunday will be mostly in the mid 70s. Lows will rise into the 40s from the 30s. Light Zephyr breezes are expected Sunday with stronger Zephyr wind next week. Highs will cool more toward the low 70s by mid-week.

The following weekend looks dry and breezy with highs in the low 70s

 

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

Cyclonic Flow continues today over the Great Basin with a slight up-slope component….Thus a few isolated showers are still possible early this week…..Another Trof affects the area Wednesday and Thursday….

Cyclonic flow continues over the region this morning as the associated upper low remains situated over the Great Basin. While the models show only a slight eastward progression of the upper low, areas of unstable air, will continue will rotate around the upper low and cross the Sierra Nevada today. Afternoon clouds and isolated showers will remain in forecast both today Monday and Tuesday. The showers will be mainly diurnally driven, and so cloudiness will dissipate each evening and night…. For the remainder of the week, there is another Trof that will affect the area, bringing cooling, wind and the chance of showers Wednesday and Thursday. However, with that said, the trough appears to be pretty moisture starved and so not looking forward to much more than a few hundred’s of an inch.

Longer Range;  The new 12Z GFS brings dry breezy weather over the area for this coming weekend. The Trof this time does not dig south. Rather it remains in the pacific NW. So dry warm weather is expected for the 1st weekend of June.  Of mention, we still have no real ridging in the week two outlook; The pattern is progressive.  This means that although no significant weather is in the Dweebs outlook for week 2, (First week of June) it would not need to change much to bring a system capable of precipitation back into the Eastern Sierra then.

 

Temp forecast for Mammoth:

 

 Mammoth Lakes
    SUNNY    PTCLDY   PTCLDY   PTCLDY   SUNNY    SUNNY    SUNNY    
      /70    39/72    41/69    38/61    31/68    39/67    44/69    

Upper Low that brought rains to the region the past 36 hours will move out of the Desert Southwest Today……The next Upper Low will approach Friday…..

Friday 8:30 AM

 

Some light rain occurred after midnight last night and .04 was recorded in the rain bucket.  Skies were cloudy along the crest and westward this morning with precipitation falling over the Central San Joaquin and Sac Valleys this morning.  The upper low was located just off the coast between Monterrey Bay and SFO. Latest computer model simulations have it almost stationary today, moving on shore about 5:00PM this afternoon. The Track is ESE and the best odds of measurable precipitation will be later this afternoon, tonight and into Saturday. The freezing level lowers to 8200 feet by early Saturday AM. This means we could have snow showers in town Saturday AM.  Although I do not expect any accumulation on our local roads, the high elevation trans-sierra passes like Tioga and Sonora are in jeopardy for between 2 to 6 inches over night into Saturday according to the NWS. So please contact CAL Trans road info for the latest.  Highs in Mammoth will be in the 50s today and Saturday. Lows in the low 30s Saturday AM

Temperature’s and the freezing level will rise rapidly Sunday and Monday!

 

The forecast for Mono County calls for Scattered Showers and Thunder storms today through Saturday.

 

Dr Howard and the Dweebs…..:-)

 

 

 

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May 23rd:  AM Update:

Yesterday was another wet day across the Eastern Sierra with thunderstorms and brief heavy rains. 24 hours amounts 8:00AM to 8:00AM were .25 hundreds. Storm total 1.06, here near the Village at Mammoth.  The upper low is broad and anti cyclonic over the inter mountain west and continues to move away from the sierra. Latest Rapid Refresh Model run from 1400Z shows most of the precip today developing east of the Highway 395, with just isolated showers over or near the sierra today. Further drying is expected Thursday before the next upper jet approaches late Thursday night.  As mentioned yesterday, the models; GFS, Euro and Canadian are trending a bit further south with this system with either the central sierra or southern sierra being its traversing point. This brings the possibility of both the front left exit region of the upper jet effecting Mammoth Thursday night into Friday morning and upper divergence from the upper low itself Friday night into Saturday. Both supply dynamics to the atmosphere in addition to the strong convective potential (CAPE), that the late May sun angle supply’s. IE, there is going to be areas of heavy rain somewhere over the Sierra from this pattern this weekend. Too soon to know where,  as it depends upon the timing of the upper divergence and where it sets up in relation to the where the upper low tracks through Central or South Central CA.  At the moment, it looks like that potential is most likely going to be to our north.  However, the freezing level is lower with this storm; 7500 to 8500 feet Friday night into Saturday and so there will be a period of snowfall possible during Saturday morning in the Town of Mammoth. It is too soon to tell how much. best guess is light amounts. Will update all Thursday AM or afternoon.

New: 9:05 AM….

Latest 12z Wed GFS tracks upper low over Mammoth Late Friday night and so little chance of any sustained upper divergence over Southern Mono County. Most likely well to our north….

 

Dr Howard and the Dweebs…………………………:-)

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It will be another day of showers and possible thunderstorms Tuesday as although the low pressure system that brought moderate to heavy rains to Mono County Monday, has moved into the desert southwest, our air mass remains moist from yesterdays rains. Daytime heating combined with the sierra terrain and a few spokes of vorticity will generate showers and a few thunderstorms today and this evening. Rainfall amounts will be considerably less than the past 36 hours. Further drying will occur Wednesday and Thursday with mainly isolated showers possible.  More sunshine expected Wednesday and Thursday means warmer temperatures and so Highs will return to more seasonal levels by Thursday (60s).

Upper Air:

Upper low at 500mb was located over Southern NV this morning and will lift NE into Utah this evening. Spokes of Vorticity will rotate around the Low today enhancing rainfall. The weather system will be out of the area Wednesday and so only air mass, diurnally driven precip is expected. It will be partly cloudy Wednesday and Thursday with a chance to slight chance of Showers and Thunderstorms.

 

Holiday Weekend:

Changes have been occurring the last two runs in the GFS model on how the next upper low, approaching the west coast Friday is being handled.  The new 12Z GFS is both slower, stronger, wetter and colder with this system.

Will take a look at the new 12Z ECMWF to see if it comes in line with the 12ZGFS later today. If it does, and remains constant the rest of the week….it could be quite wet again Friday, night and Saturday. Additionally, in that the weather system is slowing down, its timing will be tricky.   It will be cold enough for snow above 7500 to 8000 feet. Friday, Friday night into Saturday.

 

Note:   In that this is only Tuesday, this is still considered an outlook and subject to change.

 

Dr Howard and the Dweebs………………..:-)