National Weather Service Forecast Discussion

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605
FXUS65 KBOU 291920
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
120 PM MDT Wed Apr 29 2026

.KEY MESSAGES...

- Scattered showers and isolated thunderstorms continue through
  this evening.

- Highest coverage of showers and beneficial precipitation shaping
  up for the Front Range Thursday - Thursday night.

- Warmer and drier conditions expected for the weekend.

- Chance of showers returns early next week, with potential
  (50-60% chance) of more meaningful precipitation toward late
  Tuesday or Wednesday.

&&

.DISCUSSION /Through Wednesday/...
Issued at 119 PM MDT Wed Apr 29 2026

Scattered showers and a few thunderstorms have developed across
the forecast area with sufficient daytime heating and
destabilization. They are currently tracking eastward, with the
highest coverage shaping up for the eastern plains where MLCAPE
was near 200-400 J/kg. Generally lighter showers were occurring
behind that for the I-25 Urban Corridor and mountains. The showers
are expected to gradually focus near the Palmer Divide and east
central Colorado this evening and overnight where the best F-gen
lift occurs tonight, with a slight decrease elsewhere. However, we
expect some redevelopment late tonight and Thursday morning
closer to the Front Range as a weak upslope flow develops.

As stated yesterday, that`s where the uncertainty enters the
picture. Ingredients are favorable for precipitation Thursday -
Thursday night with weak Q-G lift noted and nearly moist
adiabatic lapse rates. However, it`s the amount of upslope that`s
very weak and that is likely why we`re seeing so much run to run
and model to model differences in the amount of QPF being
generated. Therefore, we still have a lot of uncertainty regarding
precipitation amounts and we`ll be somewhat conservative by
leaning toward the lower end of guidance especially east and north
of Denver. The mountains, foothills, and Palmer Divide should
still see the higher QPF totals, with some locations seeing an
inch or more. For Denver, we could see amounts as low as a couple
tenths, or as high as 1.0 inch but again favoring the lower half
of those amounts (0.2-0.6 in the deterministic forecast with the
heavier amounts on the western and southern side of the metro).
Fort Collins, Greeley, and the northeast plains will likely
struggle to see much in the way of beneficial precipitation (

NWS BOU Office Area Forecast Discussion