A Very Wet California

 If you are wondering where much of our precipitation will be headed, look to the south.  California is going to be very wet during the next week or so.

Below is the predicted total precipitation through March 18, using the European Center model.  As much as 12 inches over portions of Northern CA.    Even LA gets fairly wet.

Seattle will be drier than LA...think about that.

Why is this happening?  

Because one after another, upper-level troughs of low pressure will plunge southward into California, leaving Washington State relatively high and dry.  Troughs are associated with upward motion and precipitation.

Let me show you a series of upper-level charts that present the heights of the 500 hPa pressure surface.  You can think of this as the pressure around 18,000 ft.  Blue and white colors indicate below-normal pressures...or troughs.

At 4 AM this morning, a trough was over southern CA.

Three days later (Thursday at 4 AM), another trough is over California.

Sunday night at 11 PM, ANOTHER trough is digging down over California.

Next Thursday morning at 11 AM, another trough is pushing into California.

You won't believe this.. on Friday night, one more trough moves into California.

This kind of pattern has dominated much of this winter.

Why?  As far as I know, there is no clear answer, but something is forcing this persistent troughing over the Golden State.

With all the troughing action over CA, reservoir levels are quite high throughout the state.   

But there is a major concern.  Substantial late winter precipitation leads to bountiful growth of chaparral vegetation, which can enhance the potential for wildfire later in the year.   The past few years have had wet winters, which contributed to the huge fires around Los Angeles.