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Forecast discussion:
Another sprinkle moved through on Saturday, but it wasn't much. Now the real first warm-up of the year gets underway. From Sunday afternoon, high pressure is sitting in place over our state (Figure 1). By Monday morning, a strong ridge is moving in from the west (Figure 2). By Tuesday afternoon we could be almost 25°F above normal (Figure 3). Tuesday's high will probably break 80°F for the first time in forever.
The longer range forecast:
Still looking at Figure 4, the next day, Wednesday, a front moves in during the morning and we have about 18 hours of a really good chance of rain. Ground temperatures will be high and we will just be cooling to freezing at the end of the main precipitation event - so snow, if it occurs, it won't stick around much.
This storm system is caused by a strong short wave moving in with a closed-off low over Utah Wednesday AM (Figure 5). Our 10 day snow totals for the state look like a foot in the higher mountains, but maybe a trace/coating down around Longmont (Figure 6). For rainfall, weatherunderground.com gives us about 1/4th of an inch (Figure 4) while the GFS gives us 1/2 to 3/4th of an inch. Sorry if you were hoping for snow, but it is leaving the forecast (though there is still a lot of disagreement among the models for what happens Thursday on - so I'm not focusing on that longer long range forecast yet).