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Forecast Discussion:
As I write this, powerful wind gusts are making things thud and band around my house. Figure 1 is a snapshot of the winds reported at 5pm across Colorado. Broomfield has 69mph winds blowing while Longmont is near 50mph. The high wind warning and fire danger warning expired at 9pm Tuesday PM.
Figure 2-4 shows the dance of short wave troughs that will bring in our big storm for Friday and Saturday. Figure 2, this morning (Wednesday) has the next ridge moving in. We get calm, warm, and have mostly clear skies for a couple of days.
The longer range forecast:
Figure 3, Friday AM, shows the upper level low pretty far south, close to the four corners area, but a touch north of where it was in prior discussion. This is good for up slope flow, but a dry slot might work its way up the Front Range if we are not careful. Figure 4, for Saturday AM, has the low a bit more spread out, less intense and maybe a touch too far north for the maximum precipitation amounts in Longmont. It also means warmer temperatures and less snow chances down along I-25.
Figure 5 is an animation of the surface pressures and precipitation from the GFS from Thursday PM to Saturday PM. If you watch closely, you'll notice the low move across the northern AZ counties, then hop way up into Utah and northeast Colorado before plunging south. This will limit cold air and some of the moisture we might otherwise receive. We want the surface low to hug the CO/NM border and crawl slowly along.
Our future snow totals still show Longmont in the coating or less snow amounts. The mountains don't get as much widespread foot+ totals either (Figure 6). Figure 7 is the water itself and while there is still a bullseye west of Colorado Springs, we have a down slope or dry slot looking area from Denver north to Ft. Collins. This looks like a 1/10th to 1/4th an inch of water now for our fair city. Oh come on, give us a 2 inch rain for once!