For two and a half months the days have been getting shorter and the suns energy less direct. The annual pilgrimage of the sun is having its effect. Summer is dying for another year and if you have any doubts a little trip outdoors will convince you of that.
Yes, the long advertised cold front has passed and a damp, dreary period is ahead of us. Adding insult to injury Tuesday will be a chilly northeast wind that will keep temperature as much as 30 degrees below normal. Here's the departures the GFS shows Tuesday afternoon.
These are the actual readings the 3k-NAM depicts Tuesday evening. Ouch!
The upside to this downer of a forecast is the fact much needed rain is going to fall. The heaviest is likely through Tuesday before a more showery set-up takes over Tuesday night and Wednesday. After a lull Wednesday night and part of Thursday, rain chances increase again for the start of the weekend as the primary energy bodily emerges out of the Plains. The biggest question on the rain side of the ledger is how much falls. Models continue to struggle with the placement of the upper air energy and associated forcing. However, all models indicate most areas will see an inch (if not 2,3 or even 4 inch totals) from just this first wave ending Wednesday night. Here's several rainfall forecasts. Note some of the models such as the 3k and 12k NAM are only run out 60-84 hours due to their high resolution.
The 3k NAM (out 60 hours)
The 12 NAM (out 84 hours)
The EURO (out 90 Hours)
The Canadian GEM (out 90 hours)
The GFS (out 90 hours)
As far as temperatures go, the coolest period will be Tuesday and Wednesday with gradual moderation beyond that. Saturday should be substantially warmer with readings well into the 70s before another cool-down Sunday. The fall bounce has begun.
Last thing I will leave you with is the snow that is falling or will be falling over the Rockies and higher elevations of the central Plains. Denver had 101 Saturday and 99 Sunday and is now under a winter storm watch. Snow totals could reach 4-6" in Denver with much higher amounts in the mountains and foothills to the west. This will likely be the 2nd earliest measurable snow on record. September 3, 1961 is the gold standard with 4.2" falling before Labor day that year. There's also a chance for a record low Wednesday morning in the 20s.
Needless to say I would love to be in on the snow in Colorado but if nothing else I'm jacked to see white gold back on the charts. I'm hoping for one big nor'easter this winter to get if off my bucket list. Until next time, roll weather...TS