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Forecast Discussion:
The new cool is in place. As of 3:30pm Saturday, only a few hundredths of an inch of rain has fallen in town. [Update at 11:45pm: a streak of higher speed winds in the jet stream created a band of lift that shifted over the region dropping more than 3/4ths of an inch of rain in Longmont.] More is on the way. In figure 1, there are two lows to our west and to our east with twin bands of northward traveling precipitation organizing. That rain moved over the I-25 corridor later in the evening Saturday. Figure 2 marks the westward movement of the higher moisture air from the Great Plains for us. The storm system is gave most of the state *some* rainfall (and bits of snow up above 10,000') by midnight Saturday into Sunday. By midday Monday, the low is down in the Texas Panhandle, but rain and snow continue over the eastern 1/2 of Colorado.
In the Longer Range:
Figure 5 is the 10 day graphical forecast for Longmont showing that the temperatures remain in the low 50's early on and, after the rain chances peter out Tuesday morning, they only warm to the upper 70's by the start of next weekend. This is a real change to Fall. The warm air on Friday/Saturday comes from the rebuilding of the western ridge in Figure 6. We'll have northwest flow and the ridge just can't give us upper 80's this time. It is almost October!
On the Hurricane Maria front, it is at category 3 still, but is heading away from islands into open ocean and looks (mostly) like it will not hit the US. The 5 day forecast in figure 7 takes it close to North Carolina then moves it off east. The multiple model runs in Figure 8 show it really hook hard right next to North Carolina, but some of them have it pass very very close to people and property!
