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Forecast Discussion:
The big story for days and days to come is the northwest flow highlighted yesterday. Figure 1 shows the giant low Saturday morning in Hudson Bay and the flow around that over the top of a Pacific ocean ridge, down into the southeast US and up and out. The green line shows the dominate cold air flow (which is well east of Colorado). Figure 2 is the actual temperatures with the coldest air in purple. Figure 3 is the location of the fronts currently. Note the huge swath of up slope and frontal snow on the western extreme of this cold air flow (where the jet stream is located).
The longer range forecast:
Figure 4 shows that this is the situation still in place Friday February 9th with the low moving just a bit east.
With the jet drifting in and out of Colorado from the north, and with little ripples in the flow (red lines) moving past, we can get snow in the mountains every day much of the week - and periods of banded snow down on the plains. One push of cold air and banded snow will come in Sunday morning. We might see a dusting to an inch here. Figure 5 is the snow through Monday early morning - it is barely measurable on this map. (Though it is present nearby on the Plains).
We should see some rain Monday afternoon when this push occurs again, but temperatures are warmer. The GFS (Figure 6), shows up to an inch of snow by the next day. But the precipitation amount is less than 0.05 inches of liquid (Figure 7).
Since northwest flow will hold for most of the next 10 days, the models do put (fantasy) future snow down that adds up. Figure 8 is the 10 day guess at snowfall totals around the state. The mountains top 18 inches of snow and Longmont sees up to 3 inches. That total won't pan out, but it is an indication of the generally more unsettled pattern in place.
