| Morning cloud cover seems to be stabilizing the atmosphere slightly, but it won't change the fact that many ingredients for a message issuance day are present for the District. Upper-level monsoonal moisture and low-level plains moisture, advected into the District by surface winds out of the southeast, have combined to create precipitable water (PWAT) values of 1.05-1.20" across the District. Dewpoints along the plains are staggering for mid/late August (72 at time of writing in Fort Morgan, 66 in Limon), and with the development of the Denver Convergence Vorticity Zone (DCVZ), moisture and forcing will both be present across the District for thunderstorm development this afternoon. The current indication is that the worst of this activity will be east of the District, but pooling of moisture at the top of the Palmer Divide and in the Boulder Valley as a result of the DCVZ's circulation will lead to likely message issuance to cover bases in case the convergence zone sets up closer to the mountains than anticipated. Storms are expected to fire in the high country west of the District around noon, and move into the foothills and plains in the early afternoon. They will be scattered/numerous in nature, and carry the threat of heavy localized rainfall, medium to large size hail, and gusty outflow winds up to 60 mph before they clear out just after sunset. Skies will be calm overnight with temps in the low 60s. |
WORST CASE SCENARIO: A stationary thunderstorm, or training of thunderstorms along a boundary, may be capable of producing 2.25" in 60 minutes or less.
A LOOK AHEAD: Drier tomorrow, with storm coverage mostly over higher terrain of foothills and Palmer Divide. Then the seemingly relentless monsoon kicks back into place, with storm chances looking likely for the District from Wednesday on into the weekend.
| Location | Prime Time | 30-Minute Rainfall and % Probability |
Message Potential |
|---|---|---|---|
| Plains | |||
| Adams |
200 PM TO
800 PM |
0.3" (60%) to 0.8" (40%) to 1.5" (20%) | |
| Arapahoe |
200 PM TO
800 PM |
0.3" (60%) to 0.8" (40%) to 1.5" (20%) | |
| Boulder |
200 PM TO
800 PM |
0.3" (60%) to 0.8" (40%) to 1.5" (20%) | |
| Broomfield |
200 PM TO
800 PM |
0.3" (60%) to 0.8" (40%) to 1.5" (20%) | |
| Denver |
200 PM TO
800 PM |
0.3" (60%) to 0.8" (40%) to 1.5" (20%) | |
| Douglas |
200 PM TO
800 PM |
0.3" (60%) to 0.8" (40%) to 1.5" (20%) | |
| Jefferson |
200 PM TO
800 PM |
0.3" (60%) to 0.8" (40%) to 1.5" (20%) | |
| Foothills above 6500ft | |||
| Boulder |
200 PM TO
800 PM |
0.3" (60%) to 0.8" (40%) to 1.5" (20%) | |
| Douglas |
200 PM TO
800 PM |
0.3" (60%) to 0.8" (40%) to 1.5" (20%) | |
| Jefferson |
200 PM TO
800 PM |
0.3" (60%) to 0.8" (40%) to 1.5" (20%) |
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.