Posted: 4:01 pm Sunday, January 15th, 2017
By Kirk Mellish
The full bloom January Thaw is not expected to continue through the rest of winter.
We have been in a cycle of cold spells roughly 28 days apart since November.
So signs of Old Man Winter should be seen by the end of this Month, preceded by warmth and a severe weather threat.
IF IF the models are right about the “Sudden Stratospheric Warming” event above the North Pole and Canada and IF they are correct in projecting a the shift in the MJO/EPO/AO/NAO/PNA/WPO then a colder and stormier jet stream configuration is coming east of the Rockies end of this month into first weeks of February.
Snow may be seen as far south as Old Mexico with a storm track eventually as far south as I-10.
FORECAST 10MB Jan 25:
Note the forecast map above for the SSW splits polar vortex compared to past years where it happened:
And the February temperature departure result of the above in those years from the past on average:
FORECAST MJO moves out of warm phase into colder phases:
Could always be wrong or less extreme but at least the signals are consistent if nothing else. High latitude blocking and an active sub-tropical jet stream means storm threats as well as the change back to below normal temps by February and into March if models verify.
56 out of 91 ensemble runs show the colder change, only 35 neutral or warm. All the indices change too indicating a potential winter storm or two as well anywhere from Rockies to East Coast.
CANADIAN 500MB ENSEMBLE JAN 28TH:
But first, more of the vaunted January Thaw:
Meanwhile the southern plains ice storm makes news:
The real thing skew-T thermodynamic upper air sounding diagram Dodge City KS:
See the warm nose above 32 or lower near ground (red line).