An early season Cold Front was located near highway 80 north of Tahoe this morning. Latest 12z WRF Guidance at 500MB digs the upper trof with about 90 to 100 knot upper jet, north of the front, southwestward to the Bay Area late tonight…stalling out the cold front.   Afterword’s…. the upper jet runs out of steam and the upper trof pinches off into a weak upper low west of Alpine County, Tuesday at 12Z. Thereafter, the weak closed low shifts ESE into Nevada later Tuesday.  The WX front should flush south of Mammoth early Tuesday AM.  However, the bulk of precip is found in the unstable air behind the front associated with the cool pool aloft.  700MB temps will drop to near 0C by 00Z Wednesday and suggests a snow level of about 9500ft during the day Tuesday. Furthermore, Tuesday AM about sunrise, there could be some snow showers to lower elevations above 8500-9000K.  The chances for showers and thunderstorms will be the highest Tuesday.  Temperature’s will cool some 10 degrees today and another 8 to 10 degrees Tuesday. Nighttime lows will be in the low to mid 30s by Wednesday AM.  Expect a high of 55 on Tuesday with lows well down into the 30s by sunrise Wednesday AM.

All in all….This is just a teaser system…but actually a bit early as we usually get this around the equinox.

The models have been back peddling on the La Nina for the past few months….and now the Trades have been really cranking as the SOI has become quite positive the past three weeks.  Over the past 30 days the SOI average is up to 8.31 and climbing. We appear to be heading toward La Nina…And it just may be that Scripps is right in their SST forecast!  If the SOI remains this positive over the next few months…La Nina will most definitely be in the news!..

SOI was cranking this morning at a whopping 30.78!….  Climate models beginning to weaken the trend of warming of SSTA along the west coast after January 1st and actually bringing cooler then normal temps along the west coast later this fall into the winter……If this trend continues it is going to be a very different winter over the far west!  Cold…..late fall into Winter…500MB Upper height anomaly further west in the GOF….This will all have to be watched closely!


Dr Howard and the Dweebs………………….:-)