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Forecast Discussion:
The storm arrives Thursday pm and will be away in the evening Friday. I'll post this early (Thurs PM) since rain showers may start at any time this evening (there are show showers in Estes Park and echos around Lyons as of 7:30 pm).
A front pushes down the Plains and only gets as far as the foothills of the Rockies - since cold air is dense and forms shallow layers often. We are on the coastline of a sea of increasingly cold air out East (Figure 1). As we see in Figure 6, there is an overnight period of showers and then a midday into afternoon period of rain and or show showers (we are right on the edge again as temperatures go).
Figure 2 is the 15 hour forecast through 8 am Friday on the HRRR model. We don't get any snow by then, but Estes Park might see 2-3 inches.
Figure 3 is the total snow through the weekend from the GFS - Longmont is in a dry hole, but there is snow around us (coating to 1 inch amounts).
Figure 4 is the NAM for the same period. We are in a snow-free hole here too (so maybe a coating is possible?)
Figure 5 is the WRF and we are snow free here too. :-( I'd be happy with another 1/2 inch of rain for the plant life out there.
The longer range forecast:
We shoot back to the 50's F for the weekend then another storm will bring some moisture (I'm doubting snow, of course) Monday into Tuesday. We get colder and stay colder after that as an Arctic cold air mass takes over the Great Plains and Eastern states. They are going to REALLY feel winter starting next week.
Eclipse forecast Sunday 8:30- 11ish. :
We now have a 1% chance of precipitation. Skies partly cloudy (around 1/3rd covered by clouds). Temperatures at the start of the eclipse may be around 36°F dropping to 34°F by the end.
