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Forecast Discussion:
Extremely dry with no precipitation and warmer than normal. That is the weather forecast for today. Done.
But change is in the air. Literally.
Figure 1 is the water vapor satellite image. There are surges of moisture coming up from the southeast and the moisture from the merged tropical systems last week getting pulled up into the western states. The surface map for this afternoon still has us high and dry, but there is a cold front up north and scattered showers in Arizona and Utah up to Wyoming (Figure 2).
Some smoke leaked into northeast Colorado on Sunday - more is coming in today (Figure 3). It is thick again on the western slopes and will be very noticeable (white sky, limited visibility) around Longmont today.
For the longer range forecast (down below) - let me introduce a new model output for this column. It is the upper air moisture (between roughly 700mb and 400mb) seen in Figure 4. I created a rough outline of the 'red and yellow' or dry areas in Figure 1 and overlaid it on this map. It is not a perfect match, but it is pretty good. The deepest reds in Figure 1 match the darkest browns in Figure 4). With that, let's go into the future!
The longer range forecast:
In Figure 5, I've tried to outline the same areas that would exist as the boundary between moist and dry in the water vapor satellite image of the future. This forecast map is for midday Wednesday. If this outline matches then, we are in much deeper moisture over all of Colorado. Storms and rainfall will increase after Tuesday. You can also see the winds aloft (the little black arrows). One long barb on the arrow means the wind speeds will be 10 knots (close to 10mph). Storms that do start to dump rain will move very slowly later in the week. Locally flooding rains will occur in spots.
Figure 6 is the 10 day forecast. We get good rain chances on Wednesday, but not enough moisture to really affect the temperatures yet. The deeper surge of moisture (and another cold front) moves in at the end of this week. Rain chances increase again and temperatures noticeably drop 10° to 15° F over this last week's temperatures. A good taste of late summer approaching? We'll see...
