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Forecast Discussion:
Even though we had a marginal risk (on the eastern side of Longmont, at least) - nothing happened around her for a second day. Denver and south Denver got hit by hail and thunderstorms again. For yesterday, though, Figure 1 shows that Longmont picked up just a few hundredths of an inch of rain on Monday. Boulder didn't do much better except down on their south side where 1/10th of an inch fell.
Figure 2 shows parts of Ft. Collins picked up 1/3rd to 1/2 inch of rain while other parts of town didn't see any rain. Estes Park still only got a few hundredths. Berthoud saw a sprinkle.
Figure 3 has Denver getting up to 1 and 4/10ths inch of rain in one spot, wide spread 1/2 inch amounts, and other places getting nearly nothing. Oh the joys of thunderstorm rain coverage.
Today and tomorrow will see dry weather with temperatures near 80F. (There is always a chance of a lonely storm wandering off the mountains to get us.... but a small chance.)
Then things change for the weekend... see below...
The longer range forecast:
Our next system is a cutoff low that one can see in the water vapor satellite image in Figure 5 (red L off the California coast). As that approaches, thunderstorm chances begin to return. Figure 4 has us painted with a chance of thunderstorms on Thursday, but severe weather is just a few 10's of miles off to our east and northeast. There is guidance that severe weather chances will be much higher around Longmont on Friday.
Figure 6 is a complex (messy) upper air forecast map for Thursday AM. Our thunderstorm chances are increasing as that low (in figure 5) moves towards us (in figure 6).
Messy patterns are harder to forecast, so we'll see a lot of variability in the forecast until the weekend gets closer. Figure 7 is the GFS precipitation total by Monday next week. The super bullseye of rainfall that was near Longmont yesterday is now up around Ft. Collins and further up into Wyoming. We'll see that hop around a bit each day until it gets a hold on reality. Still, Figure 7 puts Longmont on the edge of the 1 inch rainfall region.
More later!
