First December Rain on the Horizon?

Share with Friends

The weather models over the past 48 hours have come into decent agreement that something like rain may arrive in the North Bay on Saturday. And depending on the models this could range from a shower to a moderate sized inch-plus system.

Further ahead the outlook is for a more active pattern, with storms passing through (mostly to the north) every few days beginning next week. Probably nothing major at first, but in the last month of December there is evidence stronger storms may push south into our region.

By Saturday the various models show some rain finally extending south to the North Bay. While the Euro model shows only showers, the Canadian model is more bullish, with much more moisture. (Images 1 and 2)

Starting next week, a low pressure tough is forecast to set up over the west (Image 3), allowing storms to drop further south. By around Tuesday, another storm may bring additional rain. The Canadian forecast thinks so, and most models are coming into agreement on more moisture arriving. (Image 4)

And after that? The storm door may be open for awhile. The CFS forecast now shows the chance for above normal rain in both the third and fourth weeks of December. (Images 5 and 6)

While the models have been back and forth in this La Nina dominated year, the trend is toward a more active period ahead. And with December a month when rain normally ramps up in Northern California, we’ll need some nice storms to make up the deficit that’s already accumulated so far this fall. We may be on our way. Stay tuned!