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Forecast Discussion:
It really seems that Spring arrived with the calendar date/astronomical start of Spring. Today, there is cooler air out on the Plains (and some fog maybe pushing west of I-25 in the morning - Figure 1). Over the next 48 hours the mountains (and maybe Boulder) gets a dusting of snow - Figure 2. Figure 3 is the water content (rain and snow) - there are just light showers around over this time. The rain chances fade out after about 6 am today.
The longer range forecast:
Look at the 70's F Tuesday and Wednesday as a big ridge slides past us. Warm and dry (Figure 4). Another trough approaches from the west later in the week (Figure 5). Temperatures drop to normal then below normal on Saturday. A healthy chance of rain begins Thursday am and continues through early Saturday morning. Models are divided on how much cold air comes in, but present consensus is that there will be some snow at the end of the storm.
Between now and Sunday, the GFS dumps 1.5 inches of rain on us (Figure 6). It also gives us about 5 inches of snow at the later, colder, part of the storm (it is more bullish than the weatherunderground model) -Figure 7. We have something to watch this week!