Strong high pressure has built up over the West the last week or so, blocking storm systems, causing offshore flow, and creating much warmer than normal temps.
The "zonal" jet stream we experienced throughout much of late December and January has been replaced by a wavy pattern across the Pacific Ocean and much of the United States, causing some areas in the West to experience record warm temps and creating record breaking cold in areas of the East. Areas south of the jet stream (the yellow dotted line in the graphic) are more likely to experience above average temps... and those to the north are more likely to experience below normal temps and periods of precipitation.
High pressure will stay firmly planted over the West through at least next Wednesday. High temps until then should be 85-90 degrees, with low temps mostly in the 50's each evening. Amazing winter weather, and perfect for Modernism Week!
By next Thursday, high pressure is expected to weaken and move east... allowing the jet stream to direct storm systems into the West once again. The first system is expected in CA around next Thursday or so... but it is unclear at this point if it will produce rain or just wind and cooling for us. Long range outlooks continue to show a series of possible systems hitting CA throughout the last week of February and into early March. However, it is too far out to know with any certainty which days will create stormy conditions, but the trend is toward unsettled weather again in about a week.
Get out and ENJOY the sun and toasty temps while they last!