Saturday Am Update:

A weak upper level disturbance was located across the border of Mexico into SE Ca. Mostly light to some moderate radar echos from two bands. One stretching from Vegas then SSE through Bullhead City then south to Parker, AZ, there is another weaker band over extreme SE Inyo County. All of this to stay south of our area. We have high cloudiness from another upper level disturbance Just south of SFO. Within in the west coast Trof there will be a few more weak upper disturbance’s move east and so more high cloudiness is expected from time to time. Temps will begin to cool down Sunday as the main short wave moves across Northern Ca. It will be windier Sunday PM with ridge tops gusting to 60 MPH. Local zephyr up to 35 MPH possible Sunday evening.  Drier air along with low dew points following the trof will push nighttimelows down to lower 30s in some of the chillyer valleys. Monday’s temps will be a bit below normal in the low 70s.


Upper High from the southwest retrogrades back into Ca for a quick warmup Tuesday into Wednesday. then…expect somewhat above normal highs the rest of the week. There is the possibility of some moisture advection next week as well.  However, for the time being, no rain is in the eastern sierra weather outlook.

Quick update Thursday:

The only item to add this morning is some instability that will begin to spin up over the extreme northern part of the Gulf of Ca Friday AM, then cross over  via southeastern Ca, to Laughton, Nv late Saturday Am.  This VT max spins up between a small upper low off the northern Baja coast and the upper high over eastern NM. The upper flow begins SE then becomes southerly, an indication of some kind of a tropical wave in the flow around the subtropical upper high. 

For SE Ca, This is a brief incursion of instability and moisture that will be associated with rain showers and thunderstorms for the southern desert regions of Ca. Thunderstorms may develop as far north as the Mtn’s of Kern County east to Death Valley, however the main action will probably be in the southern deserts….Vegas area,  south to the 3 corner area Friday night/Saturday to St George, Utah. 

Locally…..Other than some afternoon cloudiness in the Mammoth area Friday Pm and Saturday, this change will hardly be noticed. Mammoth is still expecting highs to climb to near 80 by Friday then upper 70s Saturday with some cooling by early next week along with a stronger Zephyr.

Discussion from yesterday:

Very pleasant weather will continue for the high country into the weekend. The East/West Subtropical high stretches from Texas….west through Southern Ca  then well out over the eastern and central pacific. The return flow is westerly through Central Ca, and although heights will be slightly higher into Friday, sensible weather is not likely to change much other then a few degrees of warming. With that said, the new 12z Wed GFS does have some convection/moisture creeping up from the south Saturday. However, for the time being, it should be more confined to the mountains from about Death Valley south. Expect some afternoon clouds here but no rain.

Some small changes ahead:

The persistent trof to the NW will deepen a bit early next week. As it confronts the subtropical east west ridge, a small upper jet (70knots) will develop off/over Central Ca Monday. The northern sierra is in the front left exit region by Monday PM which may be destablized their air mass enough to allow some convection to produce a few showers Monday afternoon into the evening hours. For the south central sierra, there will probably be just some afternoon clouds. SW winds should keep most cloudiness to the east of the crest as well.  Further out toward mid week there appears to be more afternoon and evening west wind along with cooler temps. The new GFS run does keep much more of a contrast in the air mass between the north/south and thus there will  be more WSW wind next week.


Highs in Mammoth will range from 77 to 80 the next 5 days and lows will range in the 40s at night.  WSW winds in the afternoon and evening hours will be mostly in the 5 to 15MPH range then 10 to 20 MPH range later in the weekend.

Long Range:

The Extended Range GFS has a stronger trof pushing into Northern Ca about the 21st with rainfall. This is just something to watch. The Dweebs do not see anything out over the western pacific prior to 120 hours that would amplify the pattern enough to produce such a strong rain producing system. Will keep an eye on that though.

The Dweeber…………………..:-)

Reference Glossary of Weather Terms
Disclaimer: I have been a hobbyist meteorologist for over 30 years here in the Mammoth area and I do this for my personal enjoyment. The National Weather Service saves lives every day . . . I do not. When making important planning decisions please use information provided by the National Weather Service as they are the most knowledgeable and accurate information source available today.