Wednesday, February 08, 2017

Does A Warm or Cold Winter Mean More Late Season Snow?

We hear it every winter after a period of extremes:

"This cold means a rough start to spring".

or..."These warm temperatures mean were going to get a big snow in March".

Is there any truth to this historically?

The first chart below shows some of the coldest winters (December through February) on record in Cleveland and each daily snowfall occurrence regardless of the amount from the 3rd week of February to roughly the Vernal Equinox (March 20th). I didn't use years prior to 1900 as snowfall data is frequently incomplete. The second chart shows the same daily snowfall but for some of the warmest winters on record.

Light blue days indicate snowfall under ONE INCH
Dark blue days indicated snowfall greater than TWO INCHES
Red days indicate snowfall greater than FOUR INCHES

25 days with at least one inch of snow
3 days with at least four inches of snow

26 days with at least one inch of snow
3 days with at least four inches of snow

Bottom line: A very warm or cold winter overall seems to have little bearing on late winter snowfall

Outlook For The Rest Of Winter? Written January 19th/Updated Feb 9th

Yes. It's a catchy title that probably evokes many suspect responses.  Let me explain my self:

Big cool down late this month/first week of February followed by a warm up by mid month February per the Bering Sea Rule which dictates ridge over the Bering Sea correlates well to eastern US ridge roughly 16-18 days in the future.

The GFS shows this ridge evolution quite well.

February 9th Update:

BSR verification (forecast left panel with actual heights right) for the period above looks pretty good.

This warm up may be the final nail in the coffin shutting down arctic cold for good this winter. Why? Check this much snowfall did we get from 3rd week of February to start of spring in 10 historically cold winters in Cleveland? Not much...