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More dry weather means early season rain surplus will dwindle

Green hillsides of SLO county
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The feast or famine winter weather pattern has decidedly been in the famine category for the month of January.

The Central and Southcoast are inches short of average and as we draw closer to February we are watching the early season rain surplus erode. Our rain season begins Oct. 1st and it was a wet start with a wet December. January is officially a dud which puts a lot of pressure on the end of the season to perform well or despite the fast start this rain season could end up short of average.

We can now use mid-range models to peek past the first week of Feb. and longer-range models to see to nearly the end of the month. I'm not saying no rain at all will fall, most models suggest at least some measurable rain is possible but at this point, nothing greater than .50" is on any output I've seen this week.

Thru 240 hours models essentially agree there won't be much, though the GFS likes up to .25". Looking at ensembles, which are model blends, there also doesn't appear to be a rain signal.

The longer-range models currently keep a ridge over The West more often than not which would drive low pressure "sliders" off to our east. They tend to be cool and windy but not particularly wet.

I will loudly caution that long-range models can literally flip because there is just a lot of consideration when you escape a 7-14 day window where forecast accuracy percentages are higher. That said, this is the classic LaNina positioning of the jet.

In the short-term forecast, the high surf advisory will expire at 8. Seems reasonable as the swells have been diminishing since yesterday.

More of the same in terms of local weather until Friday.

Friday the ridge breaks but only a solitary upper low looks to move east and cross into California Saturday. It will run into a dry airmass after several days of offshore flow.

No rain is expected.