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Forecast Discussion:
We have a ridge over us currently (Figure 1) with a west coast and east coast trough in place. These are just a bit closer to each other than the distance that is equal to the width of the United States mainland... so they should move forward west to east over time. There is a moderate amount of tropical moisture that has slipped into the ridge as you can see in the water vapor satellite image Figure 2. Irma is clearly on the map approaching Florida at the time of writing (late late Saturday night). Figure 3 is a future surface frontal/pressure system/rainfall chances map that shows afternoon showers over the mountains of Colorado with a few slipping east again onto the Plains. Cross fingers for Longmont rain! Irma has hit Florida by this time. Yikes.
Our smoke situation in Longmont is getting better. Figure 4 shows a LOT less smoke in the Western US that we've had in more than a week at the surface levels. Figure 5 shows a bit of smoke in the sky above us, but you can begin to breath clearly again.
Longer Range:
Figure 6 is another upper level map, this time for Tuesday PM. Irma's remains have stalled over the Tennessee Valley by this time and are dropping a lot of rain. Jose is still out there wandering in the Atlantic. The ridge is sort of on our heads still, but a weak cool front may knock a few degrees off our temperatures for a day or two.
Figure 7 shows the current (nearly midnight) Irma forecast and statistics. Due to a day of interacting (destroying) the north side of Cuba, it has been downgraded to a category 3 storm. Very warm water is still in its path and some meteorologists are thinking it will briefly hop back to a category 4 or maybe even a 5 just before landfall near Tampa. Figure 8 shows widespread 7 to 17" of rain over most of Florida over the next couple of days.
Looking WAY out to the upper air pattern NEXT Saturday night, Jose is still out there and wandering back sort of close to the east coast (Figure 9). We'll have to keep watching it all week!