Odd pattern for the upcoming week

Filed in Uncategorized by on March 29, 2008 38 Comments

A couple of weak and very minor system have brought some very light rainfall to parts of NorCal over the past few days, but most places saw no more than 0.05 in. (not enough to cause puddles!). A rather unusual and aclimatological blocking pattern will develop over the far E. Pac. this week, sending two cutoff lows riding the southern branch of the jet and making landfall in Central California. The strength of these systems is very much in question, but given the sun angle and the warm air that will be pumped in ahead of these systems in strong southerly flow aloft, some convective activity appears to be possible with both of these. Cutoffs of this nature are extraordinarily difficult to predict, so expect the forecast to change quite a bit over the next few days. Some significant precipitation is not out of the question for central/southern California, but will be unlikely¬†(suprisingly) for NorCal. The second system looks to be stronger and wetter at the moment. Deep southerly flow may be able to induce some mid-level convection in the days preceding the main storm (#2), which would be a threat mainly to mountain areas but possibly elsewhere. These systems will be interesting, indeed: 18z GFS has a rather balmy (warm and humid) airmass preceding the rain from the second system. Stay tuned…could become more interesting weatherwise over the next week…