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In Brief:
With a ridge overhead, we soar to the 80's F for a couple of days. Moisture returns with the heat - so afternoon thunderstorms (we'll have to watch the severe chances) return today (Thursday) as well. A cool front comes in for the the weekend. We cool to the 70's F and have pretty good daily chances of rain and thundershowers.
Forecast Discussion:
Widely scattered storms will form in the mountains and move eastward this afternoon (Thursday- Figure 1). High pressure at the surface and aloft mean heat - temperatures in the mid to upper 80's F.
Meteorologist Matt Makins (via Twitter @MattMakens) posted some interesting statistics. "Interesting Denver weather tidbits: In 2018 through June 10th, we had 12 days in the 90s. Yet in 2019 through June 10th, we have yet to hit the 90s and have only been 80°+ 8 times."
There are no 90's+ F in the forecast and longer range models show the cool (and moist) conditions will continue for a number of weeks to come, overall (Figure 2).
The heat Thursday will be about 7 to 9 degrees F above normal (Figure 3). Thursday and Friday are the warmest days.
With heat and moisture - will we see severe weather return? Figure 5 shows a Marginal Risk (1 on a scale of 1-5) out on the Eastern Plains. We HAVE seen this get expanded westward on the day of the event a number of times. I'll update this post if the SPC changes the western boundary.
The Longer Range Forecast:
Similar to Thursday, there is a chance of severe weather out on the Plains on Friday as well (Figure 6). It doesn't extend back to the I-25 folks, but that might change.
The cool down on Saturday (Figure 4) knocks the temperatures to some 6-8 degrees F below average.
Figure 2 shows that there are elevated chances of rain beginning Friday and continuing to Monday (green box). The coolest period spans Saturday to Monday (black box). Over the next 5 days, the GFS gives about a quarter of the state up to 1 inch or more of rain and a lot of folks 1/2 inch or more rainfall. Don't trust any one spot (like the pink dot for Longmont where there is exactly 1/2 inch of water) but this pattern and overall rainfall highlights are probably reliable.
