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Forecast discussion:
The ridge is bearing down on us. The record high at DIA for today is 95F. Many forecasts have the high at or above this. Poking into records on my own, the highest September temperature ever for Denver was 97F - this has happened a few times with 1995 being the most recent. Smoke keeps coming down from Montana and the Pacific Northwest. At times yesterday, the mountains were invisible from I-25. (See Figure 1)
Figure 1: The 500mb upper level map from Saturday PM.
A look into the near future:
The next trough (red line in Figure 2) is very potent and will drive a strong cold front down the Front Range Monday afternoon and early evening. The sad thing is... there is little precipitation associated with it. Some may see a shower or brief storm (more up in the mountains) - but the chances of Longmont seeing significant rain are very low. By Tuesday PM, the trough has pushed further south bringing in much cooler air. Highs on Tuesday may drop to as low as 68F; 30 degrees lower than Sunday. Nice!
After Harvey heavily damaged south Texas, everyone is extra aware of the next - very potent already- hurricane Irma far out in the Atlantic. Irma is already a Category 2 storm and will soon be a Category 3 storm. Figure 4 shows a comparison of a ton of different hurricane forecast models all laid together for comparison. Saturday night's GFS actually brings this storm into the DC to Baltimore region around next Sunday. But a lot can happen this week as we watch. It will keep inching in on the far eastern edge of our maps all week.
