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In Brief:
In typical Colorado fashion, a ridge is passing the state Friday/Saturday will lead to a very comfortable warm up. Then a trough moves in, cold air pours out of Canada Sunday evening and we return to the ice box with a chance of snow/ice again. It is short lived and we pop back to relative warmth on Tuesday and beyond. You are also invited to see a transit of Mercury Monday morning (clouds permitting) at the Cherrywood Observatory. Details below...
Forecast Discussion:
Today and Saturday - we enjoy the wonders of a big ridge (Figure 1) with a bit of down slope flow to warm things a few more degrees. Temperatures Saturday will be up to 10-15 degrees above normal (Figure 2). This warmth comes to an end Sunday afternoon as another front hits around 4pm (Figure 5 - dotted line). This is powered by a fast moving trough and a brief blast of northwesterly winds over the state (Figure 3). The cold air that flows down Sunday is quite shallow and doesn't make it over the mountains to the west (Figure 4).
After the front passes, up slope flow and some moisture comes back in. The window for precipitation will run from about 9pm (Sunday) to 9am (Monday). The Plains from the Palmer Divide north should see a coating to an inch of snow (maybe 2 inches in lucky spots- Figure 6) with not much rain- except further north near Wyoming, maybe as far south as Longmont- Figure 7.
The Longer Range Forecast:
The cold air is whisked away on Tuesday and beyond. We don't get really warm, but mild and dry mainly in the 50's for highs all week.
Cherrywood Observatory Mercury Transit Invitation:
Monday morning at sunrise, Mercury will be transiting (crossing the face of the sun like a mini-eclipse). If it is clear, I'll have the telescope set on the sun (with a proper and safe filter) so you can stop by and see the little dot on the face of the sun. I'm near Pace and 17th at the intersection of Cherrywood Dr. and Cherrywood Cir. east of Alpine. The sun should clear my neighbor's house around 7am and the transit ends at 11:04am. I'll be out to peek now and then - just come in the yard and look through the scope in the observatory building.