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Forecast Discussion:
We had a nice splash of rainfall midday Wednesday from a convective cell that slid off the mountains and dissipated not long after it got the ground wet around town. We are high and dry today (Thursday) with a warm up beginning (Figure 1).
The longer range forecast:
That warm up is shown in the red oval in Figure 2. We are almost up to 80°F by Saturday. Figure 3 shows the entire state, Saturday, is a bit above normal up to 20°F above normal. Unfortunately, a big wet storm system is moving in later on Saturday. We also cool down to just a bit below normal (Figure 2, blue oval).
The weatherunderground.com model gives us 1/3rd an inch of water Saturday evening (Figure 2). The storm is largely north of the state Sunday morning (Figure 4) with a rather complex couple of short waves around the state (Figure 5) in the jet stream flow aloft.
Sunday morning (outdoors sunrise services); up-slope flow will be starting and rain showers will be increasing in coverage and intensity (Figure 6). The main precipitation event kicks in later on Sunday overnight and into Monday (Figure 7). Temperatures at sunrise Sunday will be around 46°F.
The total rainfall Saturday PM through Tuesday AM may be as high as 0.75 to 1 inch (according to the GFS at this time - Figure 8). Snowfall will be healthy for the mountains but should miss Longmont with the temperatures being too warm (Figure 9).