A very moist airmass will continue for the Eastern Sierra Friday, with slow drying Saturday through Tuesday with a warming trend….Another surge of monsoon moisture seems in the cards the second half of next week…..

It was a wet afternoon and evening Thursday in Mammoth with moderate to heavy rain in many areas that continued into the night.  Mammoth at the Village picked up .32 of an inch of rain while the Mammoth AP picked up .41.  Bishop’s precipitation was the most noteworthy with precipitation totals of 1.44 inches for 48 hour amounts for the days of July 11th and 12th. Not only was this a record for the dates but the consecutive two days combined were the wettest two days in any Summer at the Bishop Airport in 120+ years.

Fridays forecast is problematic as the sky’s are over developed this morning. This means that unless we get a few good hours of sunshine, the possibility of heavy rain is greatly diminished. So here we have a situation where areas of heavy rain will be focused only in areas where there is ample sunshine that creates good heating as there will not be much movement in the storms today.

High temps will be in the 70s today with lows in the 50s. If we do not get any meaning full sunshine today Friday, highs may only get into the 60s.

Focusing upon the synoptic pattern;  shows the beginning of a drying trend Saturday through Tuesday with Tuesday being a dry sunny warmer day with no precip in the forecast. Even through dew points are expected to be on the wane the next few days, added sunshine and heating may give a boost to rainfall, although lighter amounts. This would be especially true Saturday before enough dry air gets in the mix. Sunday and Monday shows just a chance or a slight chance of thunderstorms….Tuesday looks dry and warm.

 

Longer Range: Period 19th through 24th

High pressure will begin strengthening Sunday and especially Monday and Tuesday. However, over the central and southern part of the state, this will also act to suppress convection over the Eastern Sierra while temperatures soar to the mid 80s at resort levels and 105 in Bishop by Tuesday and Wednesday.

The Global Forecast System has the continental high strengthening to the east of Eastern California near the 4-corners states by Wednesday night. there is a good chance that the gates will open once again for Monsoon Moisture and Airmass Modification beginning Wednesday night and especially Thursday and Friday. This would redevelop a thunderstorm pattern once again prior to the following weekend. Thereafter, the GFS global model builds a 600+DM upper high at 500MB over the four corners states with the possibility of deep moisture.  With its outlook for the 600DM ISO height at 500MB pushing well into Southeast CA, extreme heat would develop again for Southern California Sunday or Monday and into Tuesday, around the 23rd of July. This pattern may bring a return of the 115 degree heat many inland valleys near the Downtown LA with 110 possible just inland from the coast..  Note: This is just an outlook and is subject to change this far out.

 

Dr Howard and the DWEEBS…………………..:-)

The Pattern of Dry Southwest Flow to end Tuesday as Pacific NW trough kicks out….Arizona Monsoon developing now will work SE flow into the high country by Thursday or Friday next week….Showers and Thunderstorms to gradually increase after Mid Week…..

Tuesday AM:

 

Forecast remains on track as upper Trof now inland over the Pacific NW, then progresses east today into Wednesday. This Trof has been the suppressant, keeping monsoon moisture to the east and south of Mono County so far this Summer.  By tomorrow Wednesday, the gates will open allowing moisture and dynamics to surge northward, eventually to the CA/OR BOARDER. Dry high based thunderstorms will begin Wednesday afternoon with an enhanced risk for fire starts in the high county that afternoon. Deeper moisture is expected Thursday into Friday with wetter thunderstorms.   The chance of thunderstorms increases later in the day Wednesday, that night and especially Thursday and Friday.  Nighttime temps will only cool into the upper 50s to low 60s Thursday night and beyond.  Details about thunderstorm coverage will be on a daily bases beginning Thursday.

High temps will be mostly in the upper 70s and low 80s after Wednesday with a lot more cloud cover.

 

For you folks in Southern Californians sweltering in the heat and humidity, FYI; dew points are mostly in the mid 60s to low 70s degrees now. That is hot and humid,  with muggy nights.  Sorry to say that this pattern is not likely to change for the next 1 to 2 weeks. Hope you have good refrigeration type air-conditioning….

 

Dr Howard and the Dweebs………………..:-)

 

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It will be very warm but dry through this Monday as Southwest flow prevails aloft. High cloudiness will occur today Friday for both Central and Northern California as the remains of old Hurricane Fabio Blow off to the NE. The usual Mono Zephyr will continue during the afternoon and early evening hours with afternoon west breezes in the 15 to 30MPH range. Highs will be in the low 80s and nights in the low 50s.

The remains of the west coast trough leaves the Pacific Northwest coast and moves through Tuesday.  Thus the dry SW flow ends over Central California and we transit to our climatically favored South to Southeast flow this time of the year. This begins the moistening process for more afternoon convection in the following days. Mainly isolated thunderstorms develop in the late afternoon and early evening hours Wednesday with deeper Southeast flow developing over our region Thursday and especially Friday. Areal coverage of thunderstorms will likely increase. The details and specifics on the pattern change still to be worked out for the high country next week as too much cloud cover can shut down convection without any dynamics. One thing for sure, it will be a lot warmer early in the period with highs in the low then mid 80s by mid-week. As the Monsoonal flow strengthens and dynamics increase Thursday into Friday next week, more cloud cover can be expected with afternoon and evening convection and afternoon and early evening rain showers and Thunderstorms, leading to cooler days in the 70s. Nights will be in the 50s for the foreseeable future at resort levels.

 

Your Temperature forecast for the 8000 ft level in Mammoth:

 

Mammoth Lakes:

Fri           Sat          Sun        Mon      Tue         Wed        Thursday      Friday
SUNNY  SUNNY  SUNNY  PTCLDY  PTCLDY  PTCLDY     TS-RWS      TS-RWS
80 52/   81 50/    85 51    /84 50/    86 51/    81 50/        79 50          75/52

 

The Dweebs want to remind everyone that live is the deserts of Eastern California that young children and pets should never be left unattended in
vehicles under any circumstances. This is especially true during hot weather when car interiors can reach lethal temperatures in a matter of minutes.
With high temperatures expected in the 100 to 105 range this weekend and next week, temperatures inside of cars can reach 150 to 160 degrees
quickly with windows closed.

Early Summer Pattern of Dry Weather and Breezy afternoon and evening hours will continue through July 4th with a slight cooling trend….Traditional Summer Pattern with Full-On Monsoon flow including upper dynamics to develop over the Sierra later during the 2nd week of July….

9:15 AM July 4th:

Breezy weather on tap for this Fourth of July with seasonal temperatures. Expect highs in the mid 70s today and lows in the 40s  Gusty SW winds and low humidity in the afternoon and evening hours will create critical fire conditions. Be especially careful with fire.  Subtropical ridge in the east is still forecasted to retrograde under the pacific NW Trof.  In doing so, hot temperatures are forecasted to develop over the Eastern Sierra this weekend. Initially the air mass will be dry. Over time next week,  isolated thunderstorms will develop early next week. As we go into the following weekend the subtropical continental high will develop near the four corners states which completes the seasonal transition to summer pattern climatically.  With the westerlies fully retracted back up into Canada and the upper Trof in the mean lifting out off the Pacific Northwest coast,  early next week, the Continental High will be able to set up for a prolonged period of time. I expect this feature to become negative tilt later next week which will allow for South or Southeast flow to develop. This usually is associated with deep monsoonal flow over the Great Basin, Desert Southwest and areas of the Far West. Easterly waves, Vort maxes from subtropical disturbances may be the trigger for strong thunderstorms developing over the greater Eastern California area as we approach the weekend of the 13th and beyond. Of note, the GFS has been consistent in developing the dreaded 600 DM high at 500MB  over the Utah/Colorado border about the 17th. If that verifies, deep monsoonal moisture will invade the Far West with possible areas of heavy rain in the usual favored areas.  Along with the rain will be humidity. and possible areas of extreme heat over the west that are absent in cloud cover. One again, it will be Towns like Mammoth Lakes and June Lake that will offer the best relief for the heat.

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El Nino is developing rapidly and may reach a strong threshold of +1.5C in the Nino 3.4 region by November.  This raises the possibility of a wet Fall here in Mammoth and an early start to the ski season. September may be wet as well with Hurricane remains effecting Southern CA and the Southern Sierra.

 

Happy July Fourth!!!

 

Dr Howard and the Dweebs………….:-)

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The Northern and Central West Coast continues to experience the remains of the upper jet left over from the winter of 2018. This is evidenced by the Eastern Pacific Ridge parked out along 130west and the formation of yet another digging Trough over the pacific northwest this Tuesday and another short wave that will carve out yet another Trough further west on the Fourth of July. Both of these weather systems will bring wind and more smoke from the Lion fire eastward, as FS burn out provisions accelerate the consumption of available fuel within the fire area.

According to both the GFS and ECM models,  week 1 and 2, this should be the end of the upper jet into the central west coast as the subtropical ridge over the east, retrogrades westward and dominates the far-west by Week 2. This will also initiate the AZ/Mex Monsoon or seasonal wind which is climatically favored the middle of July for the southwest and Great Basin. So enjoy the last of the dry weather the next 6 to 10 days with only isolated TSRWs, then get ready for Summertime’s finest displays associated with SE flow by Mid-July!

In the meantime, expect a little cooler days beginning this Tuesday into Wednesday with gusty afternoon and evening SW winds up to 35 MPH. Daytime highs will cool from the low 80s today Sunday, to the mid 70s by July fourth, then 80s returns by the following weekend. That following week looks very warm with SE flow developing along with the increase of areal coverage of thunderstorms throughout the sierra later week 2.

 

Dr Howard and the Dweebs…………………..:-)