Update 9:02pm
The 0zGFS is coming out and it is not nearly as wet as the 18z was. But this is expected: to see models go up and down. What is consistent is the beginning, the Sunday thru Tuesday rain. After that there are questions as to the series of systems and their impact. I know people want forecasts cast in stone, but this far out this is not how it works. These outlooks are important because an active pattern has to be planned for, if it doesn't fully materialize at least you are ready. The wait-and-see is often too late for preps. More models complete after the news tonight. We'll see what the message is from upcoming models.
Update 7:20pm
I decided to add the full 18zGFS computer model run for rainfall. It is even wetter than the prior run I based the forecast below on. I also updated the video clip with this story showing my explanation of the new model.
We knew there was potential for rainfall next week but models we're not quite sure what to do with the trajectory of several systems. The one thing tipping meteorologists off to a big shift in the pattern was the strengthening of the jet stream on the other side of the Pacific. Several models are now beginning to see a potentially wet pattern setting up.
The first of a series of storms could hit the Central Coast Sunday and Monday with a follow-up storm at the mid to late point next week. Some computer models are suggesting up to 6 inches of rain is possible cumulatively by the end of next week. That said, the trajectory timing and intensity of the systems could still change quite a bit.
With this kind of potential people should use the time ahead of the systems to prepare items like roofing and other water management around homes. Thus far this El Nino winter season has not delivered much in the way of serious rainfall but this pattern is a taste of that kind of potential.
All that is leaping forward a little bit so let's back up and talk about the next few days. Wednesday through Friday will be very similar to what we saw on Tuesday with daytime highs in the coastal valleys in the upper 60s and low 70s and the beaches in the 60s and low 70s.
Beach and coastal valley low temperatures will be mild but the deeper coastal valleys and interior valleys will face a freezing start to the next day or two. The warmest day of the forecast looks like Saturday or daytime highs will generally be in the low to mid-70s before the system arrives on Sunday.
Again it's a very active extended forecast and the details are likely to change a little bit as the system develops in reality in the Pacific. Please stay tuned to all the latest forecasts for any watches or advisories preceding the coming storm systems.
