RECAP:   Yes its been been very warm to hot across the State.  Down in Southern California, the protracted heat wave has caused misery for many. At resort levels at Mammoth Lakes, we actually had some very pleasant weather over the weekend with highs in the 70s.  That was because when we really moisten up, we loose a lot of in coming solar radiation and thus there was a lack of surface heating.  Mammoth did have some light showers, mainly in the late afternoon and early evening hours along with some thunder. Southwest flow was initiated yesterday. With more sunshine during the day, we got up to 84 degrees on Tuesday.  Nights in the 50s

Current Pattern:

The subtropical high at 500MB was centered over SW Utah this morning,  (597DM) and is progged to weaken through Friday over AZ to 591DM. So a 60 decameter drop.  This is in response to a trof of low pressure moving into Washington state today.  For Mammoth, although heights will fall the next few days, there will be more sunshine, as our airmass continues to dry from west to east. So the effects of airmass cooling will be negligible, with only a few degrees of cooling by Friday.  At night it will be a different story as the dry airmass  allows lows at night to pull back into the 40s.  Also, expect a resumption of  the Mono Zephyr, beginning today into Friday.   Another point to make is that there are a lot of fires burning to our west.  With the upper flow becoming more WSW. Expect smoke from the west to arrive later today or tonight….

For you folks in Southern Ca, there will be some 5 to 10 degrees of cooling which will begin today. By weeks end, coastal sections may be in the 70s, Coastal Plain in the 80s and Valleys in the 90s by the weekend.

Owens Valley:

Upper flow was still SSE this morning but becomes SW later today.  So today is the last of the Thunderstorms for a while. Drying continues in the Owens Valley through Friday..

Dew-points will come down a bit as well.

Outlook:

Hurricane Genevieve is nearing Cabo San Lucas. This tropical storm will move along the Baja Coast and weaken over time over the colder water.  Moisture will be released northeastward as the systems becomes a depression, with its remains exiting possibly over central or northern CA Monday Afternoon or night.  Although there may be some showers or thunderstorms from this system, main effect will be an increase of moisture for California, beginning Saturday over Southern Ca and Sunday and Monday for the rest of California.\

There is some suggestion from this mornings 12z GFS run that another Subtropical low will spin up, this time in the “COL”, and track toward CA mid week next week. That may be a good precip producer for the fires burning throughout Northern CA. This is a long shot at this point but worth watching…

We are getting close to the time when California may benefit from a dying Hurricane that could bring beneficial rains to the state. A Window is opening over the next few weeks….

Anyway…..It is worth noting that Meteorological Fall arrives on the first of September, so the days will become notably shorter in the next few weeks along with much cooler night

Dr Howard and the Dweebs……Covering the Eastern Sierra Weather for 40 years……:-)