Summer doldrums have set in

Filed in Uncategorized by on May 27, 2007 5 Comments

Our typically persistent summer weather pattern has set in across the Golden state. Morning low clouds and fog along the coast, giving way to sunny skies inland with sesonably warm  temperatures (80-90) are a staple of our dry season weather…and these conditions have been prevalent for several weeks now. There have now been several significant wildfires in NorCal, and fire managers have reported that fire behavior has resembled fuel volatility usually not seen until late August. This means that vegetation is quite dry already, even in some of the higher elevations, and it will only become drier over the coming months.

The models have been struggling for the past few days with the development of a cutoff low off the CA coast during the middle of next week. If current prognostications hold true, the weak cutoff will indice SEly flow aloft over much of CA. If this were late July or August, we would be looking at a major monsoonal event, but given the time of year (still May!) there is very little moisture to work with. Some isolated to scattered thunderstorm activity is possible by midweek over mountain areas, which could initiate some new fire starts. SE flow will also bring warmer 850 mb temps, and temperatures at the surface will warm accordingly. Offshore flow could bring widespread 90s back into the picture, at least briefly. After that…there are no real indications of any other interesting weather. That’s hardly suprising, though.

 Also of note: Tropical Depression 1-E has formed in the Eastern Pacific. This system will probably become the first named storm of the E. Pac. season before petering out in the thermodynamically hostile environment surrounding it. There is little to no chance that any remnant moisture from 1-E would make it as far north as the American Southwest. The E. Pac. hurricane season will probably be less active than usual this year as a result of La Nina, though a pool of positive SST anomalies does still exist north of the main ENSO source region…