Fab Weekend shaping up for Mammoth….some monsoon moisture lurking for Labor Day…long range calls for the continuation of warmer then normal temps….
Friday September 2, 2011
Posted at 10:29 am by Howard
Mammoth is definitely getting back some of the Summer that it lost early in the season when periods of cool weather plagued the eastern sierra in June and July.
Global forecast models and ensembles still show an amplifying medium range trend in the long wave pattern out over the pacific, due to the constructive phasing of a tropical storm currently near Japan. The amplifying trend begins with a developing ridge over the northwest pacific which forces an impressive long wave trof near 155w, (north of the Hawaiian islands). As down stream amplification occurs, an equally impressive long wave upper ridge develops over the inter-mountain west. This will all continue the trend of the above normal temps for the Mammoth Lakes…..well through next week.
Now with all this said…..within the upper western CONUS ridge, there will be areas of upper weaknesses. Noting in today’s 12z GFS run, severel areas of Colls occur, developing upper level cyclonic flow leading to areas of upper divergence. So, not only will it be quite warm for this time of the year over the west, there will be areas of precipitation where there is dynamic forcing.
Temps in Mammoth will be in the 75 to low 80s range through much of next week, except during times of considerable cloudiness like possibly Labor Day, where it may be a few degrees cooler. So, UVM along with periods of Southerly flow is certainly possible next week, always lending to the chance of Summer time afternoon and early evening showers……..:-)
This holiday weekend should be dry except the slight chance of a few isolated thunderstorms or showers Labor Day.
Dr Howard and the Dweebs…………………….:-)
RE: Change in the SSTA pattern off the west coast “may spell” drier then normal fall.
Regarding the -SST Anomalies in the Eastern Pacific. Although the PDO is still in the Negative mode….
There is decisive SST warming in the mid latitudes off the North West Coast of the CONUS.
“If” the trend continues… Warmer then normal Sea Surface temps would probably spread south as well and make up quite a large area of the far Eastern Pacific. IE Off the California Coast northward. This would have the effect of giving us a rather dry fall with below normal precipitation and above normal temps…..
I understand from a meteorologist I spoke with yesterday, that it takes about 60 days for the upper pattern to adjust to a change in the SST pattern. The Dweebs will be following this trend……
For the loop: http://weather.unisys.com/archive/sst/sst_anom_loop.gif
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.