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Forecast Discussion:
Buckle up. This is not a big snow storm, but there is a lot to cover with it.
Figure 1 is the whole story at a glance. There were chances of showers now and then with the initial front starting about 8pm Thursday. The next, stronger, frontal push pours down the Front Range mid-morning increasing the chance of rain, that quickly changes to snow around midday. Snow chances continue until midnight then precipitation tapers off.
Figure 2 shows the cold air Thursday PM pouring out of Canada coming our way. By about sunrise Friday - temperatures are still above normal, but the leading edge of the really cold air is visible in Wyoming and Nebraska and a bit into Kansas (Figure 3).
Six hours later, Figure 4, the cold air has made it all the way back through Boulder County and is filtering down into Denver (noon). Winds at this time are pretty stiff at 20mph with gusts to 30mph as seen in Figure 5. Remember, the closer the isobars, the stronger the wind.
The coldest air is here around sunset (Figure 6). Temperatures on the plains go from 5-10 F above normal Thursday night to about 30 F below normal. Oh the cold.
As quickly as it comes, it retreats to the east. By Saturday morning (Figure 7) we are returning to normal and the extreme cold on the plains is fading out.
Lets now turn to the precipitation. Though showers may occur all night Thursday into Friday AM - the real precipitation is impacting the mountains and coming down from Wyoming by sunrise today (Figure 8). By noon (Figure 9) fairly heavy snow is falling north of Denver. For the evening drive and the Rockies game (Figure 10) snow is falling from Wyoming almost to New Mexico. It looks bad for driving and for sports. The storm is moving out with the back edge of the snow just south of Ft. Collins by midnight Friday into Saturday (Figure 11).
For totals: The GFS in Figure 12 shows Longmont in the 1-3 inch area. Ft. Collins in the 2-4" area. Estes Park 3-6". Denver 1/2 to 2". Boulder 2-5". The Palmer Divide communities will see 1-4". Initially warm, and wet, ground will limit snowfall totals initially.
For water total- Figure 13 gives us about 1/4th inch (locally 1/2 inch, especially west of town).
The longer range forecast:
Figure 1 shows another system coming in around 3pm Saturday with rain chances through Sunday pre-dawn. Temperatures stay above freezing day and night. Comparing figure 14 and 13 - the mountains pick up another 1/2+ invh of water while we get another couple of 10ths of an inch of water. THEN by mid-week, we may see our first 80'sF. Wow, what a state!
