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Forecast Discussion:
Since showers are moving in on us (the 'storm' is underway -Figure 1) - I'll post early today. The chance of showers peak about when this post goes up - from 4-7pm. Sprinkles will fade out by midnight (Figure 2). Note, that funny R with an arrow and dot mean thunderstorm with light rain, in meteorology speak. The HRRR model (Figure 3) has spotty showers around Wednesday PM. It happens to miss Longmont in this run. Most areas that do get water get a trace to 1/4th inch.
The longer range forecast:
There is another disturbance in the flow moving through Saturday - it isn't much at this point (Figure 2). The next big change in the weather pattern moves in Tuesday next week (also Figure 2).
The upper air pattern on Tuesday shows a short wave passing over the state and a big trough digging into the western U.S. (Figure 4). This will bring a cooler and wetter period for mid-next week on. Rainfall totals over the next 10 days look to remain under 1/2 inch for Longmont (Figure 5) and more snow falls in the mountains (up to a foot in places -Figure 6). We'll keep an eye on it all as the week passes!