Temperatures (November): Valley Mean Temperatures are expected to vary at +2 to -3 deg F of average (as a whole) through the end of November. This is not because a cooler air mass will move in, but rather the anomalous early season rainfall across the entire region is expected to cause valley fog (interfere with temps). An anomalously cold air mass is not expected to move in through the end of November. You may remember last year when valley low temps were in the upper 20’s to low 30’s from November 25 through early December.
Temperatures (Dec-Jan): For December, current probabilistic signals are for average to above average mean temperatures. These same signals also extend into January. Therefore, probabilities as a whole favor average to slightly above average mean temperatures through the end of January. Note that this is not set in stone and it doesn’t mean we won’t have cold air seep into the valley.
Precipitation: After this next precipitation event tonight through tomorrow morning, high pressure is expected to build in. This will likely cause a stretch of dry weather through at least November 19. Around Nov 20-21, a cut-off low pressure system may bring small chance of precipitation to parts of CenCal and SoCal. At this time, chances for rain across the valley will probably be slim to zero. Thereafter, dry weather has a higher probability that not through the end of the month. Signals for Dec, Jan are for below average precip (as it looks now).