Wednesday AM:

One more day of seasonal temperatures for the Mono County area then a warming trend occurs Thursday into Friday as the current westerly flow aloft shifts east and higher pressure aloft builds in from the south.  The ridge is weakened by a weak trof that moves through Saturday and Sunday with little change in our weather with the exception of a little more Zephyr Breeze in the afternoon and evening. Mammoth Lakes weather will be beautiful through the holiday weekend with highs today Wednesday in the mid 70s pushing to near 80 by Thursday and then up to 83 by Friday. Little change in temperature is expected thereafter through the Fourth of July. Lows at night in the dry air will get down to the 40s after midnight. Expect the usual afternoon and evening Zephyr breezes in the 10 to 15 mph range with the same type breezes in the 15 to 25 MPH range Saturday and Sunday. The weather will be as perfect as one could hope for.

Longer Range:

The weak trough that drops into Central and Southern CA this Saturday and Sunday will provides a dry southwest flow over Mammoth. The GFS keeps the trough more intact over Southern California through Tuesday then lifts it out over the Great Basin Wednesday. The ECMWF model retrogrades it off shore early next week which allows an area of high pressure to build closer to the Four Corners than the GFS. This scenario results in the mid level flow turning southeast to south across Arizona and Southern Nevada Tuesday and Wednesday. This would begin to open the door for monsoon moisture over New Mexico first, then expanding west into Arizona prior to the following weekend. In that both global models differ on this at this time, confidence is not great. Should the upper flow turn SE over Southern CA by the end of next week, moisture advection would occur over the state along with air mass modification and Summertime thunderstorms would begin over the sierra with the areal coverage increasing by the day.



Finally a break in the heat over much of California this week as the subtropical high gives ways to short wave energy transiting the Pacific Northwest.  With a more prevailing WSW flow, afternoon convection will be minimized with a more stable air mass. Drier air will mean cooler nights and with lows in most areas in the upper 30s and 40s. Daytime highs will be mostly in the mid to upper 70s, seasonal for this time of the year. Light to moderate Zephyr winds will blow mainly in the afternoon and evening hours, 15 to 25 MPH with some gusts to 30 mph.  Although there will be some rebuilding of the subtropical continental high late Thursday into Friday, high temps should not exceed the low 80s Friday. Additional short wave energy passing to our north over the holiday weekend and the fourth will keep our weather very comfortable and dry. There will be periods of afternoon and evening Zephyr winds over the next 5 to 7 days. Highs will range mostly in the upper 70s and low 80s the end of the week through the holiday.


Dr Howard and the Dweebs…………………:-)