Archive for April, 2018

After a warm up the next few days….unsettled weather returns next week with one storm exiting Monday Night and another weaker system exiting Thursday…..Thereafter, the weather pattern is making efforts to transition to a warmer drier pattern……

Although another round of cold unsettled weather is likely Sunday night into Monday night, and possibly again Wednesday night into Thursday, there are signs that the long-awaited transition to warmer, spring weather over California is beginning to take shape in the not too distant future..  For the time being, the long-range outlook, which is typically unstable this time of the year continues to show the active pattern of the past 6 weeks continuing into next week. However, the polar Jet looks like it will shift north by the following weekend. Much weaker westerlies are progged into the last week of the month, with the exception of one cold storm the end of the month.  Overall, this means that unsettled periods are shown to be less frequent during weeks 2 and 3. However, this is not to say that we are done for the Spring, as the usual cut off low season has yet to develop. Furthermore,  the weakening of the upper jet over the pacific at this latitude, will change the way precipitation develops over the sierra. Convection, upper diffluence and unstable air that accompanies, will play a more dominant role in the precipitation process over California. This is in contrast to the strong upper divergence of Winter and early Spring that the upper jet supplies.

As far as sensible weather, the next few days will be warmer with highs in Mammoth reaching about 60 by Saturday and the chilly lows in the teens of late will rise into the 30s by Sunday. The next weather system moving into the High Country Sunday will bring an increase of wind by afternoon with snowfall developing Sunday night and continuing into Monday night. The storm has the potential to bring at least a foot to the Upper Mountain by Monday evening.

For your powder hounds…..plan on Tuesday morning the 17th for one of the last cold powder days of Spring, as the next storm may not arrive until the very end of the month. A few more storms are possible in May…


The Dweeber…………:-)

New Week Arrives on a Fair Note….Then a Return To Unsettled Weather Mid Week…..No Major Storms on the Horizon this Week….

Latest guidance favors the European Model which has the most consistent ensemble members and thus “Trumps” the GFS. (No pun intended)  The Wednesday night system looks pretty windy, with the potential for light to moderate precipitation.   There is another system out there for next Monday. Again the Euro seems to be handling the upper flow better with a slower approach and with better climatology showing a closed low associated with it. The Euro has another closed low system in back of it for the middle of next week as well.


Monday AM the 9th:

The Dweebs Monday morning outlook is prefaced by the fact that we are approaching mid April now. Weather systems tend to move slower, become cut off from the westerlies at times and in general, model accuracy becomes ever more diminished with every calendar week ahead. The idea of trying estimate snowfall and rainfall amounts on a time scale of a week in the winter is much easier than at this time.  So as a result, more general outlooks for precip a week ahead will be issued and much subject to change.

We are currently in pattern that is highlighted by a series of smaller scale systems this week and next, that for the most part will bring lots wind at times;  little or no precip to generally light to moderate amounts of snowfall.  Light precip is defined as being 1 to 6 inches and moderate 6 to 18 inches of snow.  These are systems that have a fair amount of cold air.  The focus this week will be windy weather Tuesday afternoon and again Wednesday afternoon and night.  The Wednesday night into Thursday morning system holds the best chance for snowfall. The new 12Z Monday GFS has up to 1.2 inches on the west side of the Sierra, while last nights ECMWF had about 1/2 of that.  Best guess at this time is about 6 to 10 inches over the upper elevations by Thursday PM.

There will be periods of large swings of cooling and warming between weather systems. As a result, some of these weather systems will have strong thermal gradients and strong winds at times.


Dr Howard and the Dweebs………………………:-)


The new week will offer a mixed bag of weather as the pattern remains progressive with a series of ridges and troughs migrating through the west coast. And typical for spring, some of these systems will bring windy weather over the upper elevations. A NW jet over the weekend will keep the upper elevations quite breezy as well…..Then a possibly stronger storm the following Sunday night into week 2. Overnight lows have now returned to below freezing and highs will wildly swing from the 60s to the 30s then 50s later this week.


Over all typical Spring April weather.  The mid-week storm may bring between 2 and 6 inches of snowfall


Dr Howard and the Dweebs…….:-)

Atmospheric River moves on shore later today…Latest model runs trend Bullseye further north to Tahoe…..Much colder storms expected next week……

Latest Update on the AR this Saturday morning the 7th:


  1. The AR will be out of the Mammoth Area between 11:00am and Noon.. A few showers may linger….
  2. No snow is expected in the Town of Mammoth
  3. Little if any snow is expected on Mammoth Mt following the system…..Above 9500 feet there may be an inch or two.
  4. Cooler air is following the rain, and precipitation should be mostly over by the time the rain ends.


Two more windy systems will move in mid-week. They will be colder and snow fall will be in the light category. 1 to 3 inches Tuesday night. and the system for Wednesday night into Thursday storm will bring the best chance of 6” plus of snowfall on Mammoth Mountain



Some great news this morning…..


The good news this morning is that model consensus shows that the AR will affect the Northern Sierra with the greatest precipitation totals while the southern portion of the Central Sierra will have mainly moderate amounts. Computer generated QPF now showing up to three inches of water over the crest with about 2 inches in town and about an inch of water along the highway 395 corridor.  Rain is likely to reach the sierra crest up to 12,000 before the snow level comes down to 9000 on Saturday.  Additionally,  there is the suggestion that snowfall amounts will be in the 6 to 12 inch range on the mountain Saturday and a few inches possible in town. Down the road….two colder storms look likely to bring light to moderate snowfall Tuesday into Wednesday AM and again Wednesday night into Thursday. The Wednesday/Thursday system looks stronger than the Tuesday night storm and may bring enough snow in town for a plow.

Precipitation may begin as snow around Midnight tonight, even in town Friday, until our air mass becomes saturated later in the day, so do not be surprised if we get a couple of inches of snowfall early Friday before it turns to rain….


Dr Howard and the Dweebs………………….:-)