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Forecast Discussion:
Here comes the cold!! (And a bit of snow.)
While a GIANT storm moves off into the eastern U.S., another, smaller storm is moving through the desert southwest towards us and regions south (Figure 1). With my added colored arrows (Figure 2) you can see the big swap of cold and hot air going on (Texas had severe weather because of this 'clash'). Temperatures today will be 16-18F below normal with a high only around 25F. Brrrr. (Figure 3)
The loner range forecast:
This very cold period will extend through Saturday. We have a brief warm up on Sunday to a few degrees above normal with a warm front, then another cold front brings in a inch or two of snow Sunday night into Monday morning (New Year's Eve) - Figure 4. That Monday-Tuesday cold shot will be as sharp as what we are experiencing today (Friday). The snowfall (from the GFS) is heavier to the southwest and southern parts of Colorado - still Longmont may pull 1-2" from this model (Figure 5).