Aerial coverage of Thunderstorms will increase this weekend as a weak southerly flow brings an increase in high level moisture…Expect a drying trend early next week…Then more Thunder after mid-week…..

Towering cumulous developed mid to late morning over Mammoth Lakes as dew points increased. Thunderstorms developed later this afternoon mainly east of highway 395 with a particularly strong cell near Mono Lake at 6:00pm Thursday evening. Expect a repeat again Friday. High temps will continue in the low 80s then mid 80s Saturday.  As we go through the weekend the Continental four corners high builds westward, centered near the southern NV/Utah Border Saturday. Expect an increase in southerly flow Friday night into Saturday with some pockets of impulses kicking off a better chance of thunder storms Saturday afternoon and evening…This is true for Sunday as well.  Lows at night will be in the 50s

The outlook for the upcoming week shows an increase of westerly flow and drier air working back into Mono County Monday into Tuesday. That will put an end to the thunderstorm’s once again,. Early morning lows will move down into the upper 30s and 40s by Tuesday night.  Daytime highs will cool to the upper 70s.  By Mid Week, the upper high begins to build westward again with sensible warming into the 80s by Thursday. Monsoon moisture along with air mass modification is likely to occur again Thursday and Friday next week, for a return of thunder for Eastern CA.

 

Dr Howard and the Dweebs………………..

 

 

 

 

Waiting for the Monsoon!…..Highest Temperatures of the Summer for the next 10 days….Prior to Monsoon Push…..High Temps in Mammoth in the 80s now with Airmass Modifacation and Moistening expected by Weeks End….Only high based isolated storms expected this week….

High temperatures in Mammoth reached 86 degrees on Saturday with a slight weakening of the upper high expected the next few days…It was a very mild night as well with early morning lows in the upper 50s Sunday morning. Breezes have been light over all.

Forecast Models week 1 and 2:

What I see for the State of California is a lot of hot July weather with Southern CA becoming more humid in the coming weeks. For the time being, there will be a lesser amount of thunderstorms for the Central Sierra.  Now this may change when we get into week 2 and 3. However, for the time being, the Gulf of Alaskan low is far enough west to allow the continental high to periodically build west for scorching heat over the state, with the upper flow configured more SW/NE  keeping our flow more SSW shunting a lot of the moisture and dynamic’s to our south and east. As mentioned above, a slight shift in this pattern would provide a “northwestward surge of the above” Beginning about the 15th, then during the 2nd and 3rd week of July. Without a good surge of moisture and dynamics, it is going to be a very hot Mid to late July for Sierra Nevada and California. Southern CA will likely continue to have more often than not, hot weather except for the immediate coast. Coastal dwellers of southern can thank the Chilly Sea Surface temperature for its cooling effect. It will only be times of off shore flow that you will not benefit for the SSTs cooling effect.

Models peak in the heat looks to be about Friday July 21st as a 600DM upper high at 500MB builds over Ely, NV that afternoon. Heights are north of 597DM over Mammoth and Bishop.  That is usually good in drier air for record highs in Mammoth and Bishop, with about 90 in Mammoth and 110 in Bishop. If by chance we have a monsoon push with that upper high, then it will be hot and humid with afternoon thunderstorms, but no records. I am sure that the models will need some tweaking before hand and so I will update this mid-week.

Some incipient thoughts about winter of 2017/18:

Changes; The QBO after being in its positive phase for 24 months has become negative during the month of June.  However, it is only weakly negative and may flip back.  A positive QBO by some climate scientists is associated with a Trof in the west.  However, this is not a widely accepted concept.

SSTA’s. The warmer than normal sea surface temps in the Bering Sea and North Central Pacific during last fall has become warmer than normal again after being cooled over the Winter. The Warm Blob is still gone from the NE pacific.

ENSO is currently in a very weak El Nino phase/ENSO neutral, and is forecasted to cool again this Fall and Winter.  This leads to a greater bias towards more AR events for California.

Sun solar cycle is heading for solar minimum and which again argues for a wetter winter for California.

At the Moment, The Dweebs Bias is still wet for the Winter of 2018.  But not as wet as last winter.

 

Dr Howard and the Dweebs………………..:-)

Seasonal Temperatutres return this week as the strong upper high gives way to troughing in the Pacific Northwest…..There will be a slight uptick in temperatures this weekend…

Wednesday AM:

One more day of seasonal temperatures for the Mono County area then a warming trend occurs Thursday into Friday as the current westerly flow aloft shifts east and higher pressure aloft builds in from the south.  The ridge is weakened by a weak trof that moves through Saturday and Sunday with little change in our weather with the exception of a little more Zephyr Breeze in the afternoon and evening. Mammoth Lakes weather will be beautiful through the holiday weekend with highs today Wednesday in the mid 70s pushing to near 80 by Thursday and then up to 83 by Friday. Little change in temperature is expected thereafter through the Fourth of July. Lows at night in the dry air will get down to the 40s after midnight. Expect the usual afternoon and evening Zephyr breezes in the 10 to 15 mph range with the same type breezes in the 15 to 25 MPH range Saturday and Sunday. The weather will be as perfect as one could hope for.

Longer Range:

The weak trough that drops into Central and Southern CA this Saturday and Sunday will provides a dry southwest flow over Mammoth. The GFS keeps the trough more intact over Southern California through Tuesday then lifts it out over the Great Basin Wednesday. The ECMWF model retrogrades it off shore early next week which allows an area of high pressure to build closer to the Four Corners than the GFS. This scenario results in the mid level flow turning southeast to south across Arizona and Southern Nevada Tuesday and Wednesday. This would begin to open the door for monsoon moisture over New Mexico first, then expanding west into Arizona prior to the following weekend. In that both global models differ on this at this time, confidence is not great. Should the upper flow turn SE over Southern CA by the end of next week, moisture advection would occur over the state along with air mass modification and Summertime thunderstorms would begin over the sierra with the areal coverage increasing by the day.

 

Monday:

Finally a break in the heat over much of California this week as the subtropical high gives ways to short wave energy transiting the Pacific Northwest.  With a more prevailing WSW flow, afternoon convection will be minimized with a more stable air mass. Drier air will mean cooler nights and with lows in most areas in the upper 30s and 40s. Daytime highs will be mostly in the mid to upper 70s, seasonal for this time of the year. Light to moderate Zephyr winds will blow mainly in the afternoon and evening hours, 15 to 25 MPH with some gusts to 30 mph.  Although there will be some rebuilding of the subtropical continental high late Thursday into Friday, high temps should not exceed the low 80s Friday. Additional short wave energy passing to our north over the holiday weekend and the fourth will keep our weather very comfortable and dry. There will be periods of afternoon and evening Zephyr winds over the next 5 to 7 days. Highs will range mostly in the upper 70s and low 80s the end of the week through the holiday.

 

Dr Howard and the Dweebs…………………:-)