Cold Blast Coming, But It Won't Last Long...

While we remain in daily near record/record breaking heat, a change in the upper air pattern will finally make us feel like Winter with freezing temperatures coming to the North Shore and away from Lake P. south.  In fact, this will easily end up being the warmest December at MSY on record (1946) and not by just a little, but a lot.

I've drawn the West Coast trough that has been in place for weeks with several lows bringing much needed moisture to California.  Look at the below freezing temps to the coast at Seattle and Portland with most of California in the 40s!

The upper ridge over the SE has blocked most of the cold air from us, but that's about to change.

The top graphic is today's upper flow with the next being valid for Sunday morning.. Note the dip over the Southeast that will bring the chill.  However, that dip won't dig and will quickly lift out allowing a rapid warm up by mid next week.

So in the short term, the cold air stays to our north as the current upper energy triggers some strong storms north of us.

As the next upper disturbance approaches late Friday, there could be another round of severe storms as SPC indicates for Friday.

With brisk south winds over night, temperatures will be around 70, well above the average/normal low of 47.   But the cold will arrive before sunrise on Sunday with full Winter weather gear needed for three days.   Models are hinting an even stronger cold blast coming for late next weekend.   Bottom line, January will be much colder that December, and for many that will be OK.  Stay tuned!