2008

The next 48 hours will feature anomalously warm weather across the state of CA. Record highs are expected to fall, especially in the Bay Area, where local downsloping winds may heat PM temps well into the 80s. The Central Valley will be cooler, with highs generally in the mid to upper 70s, as cold  air advection aloft and efficient overnight radiational cooling will keep temps down there. SoCal will bake in 85-95 degree November weather, and in conjunction with a substantial offshore wind event, fire danger will be extremely high for at least a few days. A local barrier jet may develop on the west side of the Sac Valley tomorrow, bringing uncomfortably dry and dessicating conditions to people and plants there. Dry and generally mild weather (though with more seasonable afternoon temps) will be the rule well into next week. The GFS has been forecasting the development of a much more active pattern out beyond day 7 for several days now. However, as is often the case this time of year, the period of increased activity keeps getting pushed back with each new model run. Some individual runs have brought some very impressive storm systems into  CA in the 16 day period, but there is very little consistency. It is at least somewhat encouraging that the GFS isn’t as dry as it was a couple of days ago, with no rain for CA at all in the 16 day run. More than anything else, I expect, the increased activity on the GFS can be viewed as a possible trend towards wetter weather at some point in the future. Being mid-November, that’s not exactly a risky prediction. One item to keep an eye on, as always, is the current phhase of the MJO. Currently, the MJO signiture is over the Indian Ocean and is rather weak. Some models are showing an increase in the strength and an eastward propagation of the enhanced convection associated with the MJO in the 1-2 week period, which would bode well for CA rainfall. We shall see.