Archive for year 2021

Chilly Upper Low over the Far West expected to bring light snow to the High Country Wednesday before Exiting Thursday……Fair Warmer weather expected for the weekend…

It was quite the windy day across Mono County Tuesday as an area of low pressure deepened along the Northern CA/NV Border. Winds were clocked above 60 MPH in the mid afternoon in Bishop. The High Wind warning well advertised by the NWS nailed it!  Cold Air advection poured into Mono County during the Mid Afternoon.

By Wednesday morning, the upper center will be near Tahoe before tracking east through Nevada during the day. As the low shifts east, an area of baroclinicity will drop south Wednesday morning initiating the chance of snow shower’s. By the afternoon Wednesday, the WRF model has the upper center very near the Utah Border, while a rather impressive Vort Center swings SE from west of Tahoe to Mammoth During the Mid to Late afternoon hours.

This Vort center is coming through during the period of max heating and instability. So it could get kind of wild with areas Snow Thunderstorms later in the afternoon throughout the county including Mammoth Lakes. Snowfall amounts could be several inches in some areas with the snow level about 6000 feet. Precipitation will wind down by Mid Evening…. Highs will be chilly…In the low 40s… Lows in the upper teens and twenties Thursday AM.

 

The upper low exits quickly Thursday morning with a sunny day expected. High temps will be near 50 with a warming trend.  The Weekend looks stellar with temps warming to the low 60s by Sunday!

MJO: Attended the CPC Tropical Discussion this AM

Changes are coming to ENSO as a robust MJO now over the Western Pacific shifts east across the pacific the next two weeks. Strong westerly wind bursts are occurring ahead of the MJO and an air/sea Kelvin Wave is pushing warm water east over taking the cold La Nina waters. This MJO is expected to put the nail in La Nina over the next month or so.

With MJO in phase 7, the composites suggest warmer than normal weather next week with dry weather continuing.  However, the MJO remains strong into Phase 8 and that suggests that another change in the pattern may return precipitation chances to the Sierra, during the last Week of April!   Where was MJO in Phase 7/8 in February!   That time of the year, a strong MJO in phase 7/8 can bring pounding rains and snows for California and the Sierra. However, not this time of the year…..Although we may get a late April Surprise………………..;-)

Start thinking about water conservation now, as its going to be a rough Summer for California.   We can only hope for lots of wet Thunderstorms for the high country.

 

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

 

 

Breezy Weather with above normal temps to continue into the weekend….Possible pattern change middle of next week

It’s that time of the year again. Breezy afternoon and evenings are likely to continue for some time as we remain sandwiched between a subtropical ridge and trofing to our north.  The upper jet is split too with the northern branch sending short wave trofs into the pacific NW and northern Rockies.  Each one of these systems increase the gradient.  Height rises this weekend will serve to increase our temperatures. Highs that have been running 57 to 58 degrees will bump to the Low 60s, Saturday into Monday. Lows at night of late have been in the 30s due to nighttime light to moderate wind. It may cool a bit Saturday AM into the upper 20 as winds will diminish a bit.

The Main features affecting our current weather is being fed by a Polar Vortex along the north coast of AK. This Negative tilt extension is bumping up against a subtropical ridge at 18000 feet. (500MB) The result is above normal temps and wind in the high country.

Over the next 7 days, this PV resets south of the Bering Sea and the result is a positive tilt ridge into Western Canada. The return flow over that ridge may dig a trof into the Great Basin toward the middle of next week.  That pattern would bring cooling, wind and the chance of some light snow.  Now, the NWS is going with persistence through mid week next week, as there are not enough ensemble members to challenge the sensible weather pattern we currently have.

Looking at the MJO phase space, it shows a robust MJO moving into phase 7. This suggests that our exceptionally warm weather may not last beyond early next week. It also suggests in its composites, this time of the year, precipitation over Northern CA later next week.   So, odds for a change in the pattern is being supported by the MJO for at least cooling out west.

As many have heard, we are expecting an increase in drought conditions out west.  However, the ECMWF climate model shows a more normal Monsoon Season in July and especially August. This typically does not help CA, but may bring some relief to AZ and the rest of the Desert SW.

Above normal temperatures are expected July and August and high temperatures may hit 90 degrees at least one day in Mammoth this Summer, about mid-July. With more normal or even an enhanced monsoon, comes the possibly of more thunderstorms. The Peak of Thunderstorm season in Mammoth is late July and early August.

 

Spring weather has Sprung with a warm day expected Sunday….Dry Cold Front to bring Cooling and Wind Tonight through Tuesday with another warm-up Mid Week……Easter Sunday and beyond may be unsettled……

3-31-2021  10:50AM  (UPDATE)

High pressure builds over CA today with ridging into Friday.  Above normal temps are expected into the weekend with highs in the mid to high 50s in Mammoth with lows mostly in the 20s. Winds will be light today and Thursday.

The weekend weather shows periods of high clouds as SW flow develops ahead of an approaching Trof Sunday. Little change in temperatures are expected through Saturday. 500MB height falls begin Sunday as a positive tilt Trof elongates SW Sunday with a split that spins up a closed low off the Central CA coast Sunday. 250MB upper jet forces moderate to strong winds over the upper elevations Sunday. Sunday will be a bit cooler than Saturday. Winds will further increase Sunday night and begin to work there way down into the lower elevations. Jet”O”Geneses  develops Sunday into Sunday night as some weak phasing with STJ. Thus subtropical moisture “Advects” into California Sunday Afternoon into Monday AM. A cold front moves through the Sierra Monday AM with wind, cooling and showers. As the upper Trof pushes through Tuesday evening, clearing is expected Tuesday night with flat ridging to follow Wednesday into Thursday next week. (Fair Weather).

 

Longer Range: There is less certainty with the storm for the end of next week.  Weather systems are appearing to slow down now and become more cut off.  It may be that the end of next week’s storm is pushed back to mid month as our wet season winds down and another drought year is becoming more inevitable with each passing week.

April 1st water content for the Southern and Sentral sierra will show 51% to 55% of normal, although Mammoth Pass added substantially to that with the moderate AR, late last January.

The storm early next week may drop up to a foot of snow over the crest by Tuesday evening if everything works out just right!!

 

Dr Howard and the Dweebs…………………..:-)

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It was a beautiful day in California Sunday. Temperatures were above normal, (50s) and it really felt like Spring! The upper ridge aloft will give way to a system tracking through the Pacific Northwest tonight and into the Northern Rockies Monday. The Upper Trof will bring wind and cooling for the Mammoth Area Tonight through Tuesday. Tuesday look to be the coolest day with highs in the mid 40s with lows in the upper teens and 20s Wednesday AM.  By Wednesday afternoon, ridging is back and it builds through Friday, Highs will reach the upper 50 to low 60s, Thursday into Friday.  By Friday night, winds increase as a Trough deepens down the coast . This may bring precipitation back into our area as early as Saturday night or Easter Sunday. It is just too far out for any certainty. By week-two as the MJO heads into phase 7, the odds increase for a significant unsettled pattern change, the week following Easter Sunday.

 

Dr Howard and the Dweebs…………………….:-)