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Forecast Discussion:
As the heat cranks up (we'll talk about that in a moment) - smoke continues to be a problem. There are a number fires out across the southwest and they are making the sky hazy. We are missing the worst of it today (Figure 1).
Moisture is slowly increasing (and largely, it would be happening even if hurricane Bud hadn't been a 'thing'). Figure 2 shows the water vapor satellite image and there is Pacific moisture, gulf of California moisture, and Gulf of Mexico moisture finding its way towards us. We had severe thunderstorms out in the eastern Colorado (green arrows) fueled by this moisture.
Figure 3 shows that, before the weather changes this weekend, we approach 100F again. There will be a chance of afternoon thunderstorms around the state, but nothing severe is expected today.
The longer range forecast:
Tomorrow, the change begins. A front pushes into the state. That, plus the better moisture around, will make marginally severe weather conditions possible for NE Colorado. This doesn't include Longmont at this time (Figure 4).
The big news is the moisture from Bud. Bud's forecast is not towards southeast AZ (as it was yesterday) but is now towards extreme eastern New Mexico on a path towards Colorado (Figure 5). This is the circulation center. The GFS has the low center further north (northern New Mexico) for Saturday evening, with the bulk of moisture is ahead of the former tropical system's center up into Colorado (Figure 6).
Figure 7 is a (probably over zealous) estimation of the rainfall for the next week. I've added the approximate locations of the four big fires. IF this verifies, this is over an inch of rainfall for all of the hot spots. The extreme rainfall in NE Colorado seems to come from a big thunderstorm complex, along a front, that invades the state on Monday into Tuesday. We'll keep an eye on all of it. Longmont seems to pick up around 1 1/2 inches of rainfall over the next 8 days, from the GFS.
