Category: Climatology (Page 1 of 71)

These posts contain information about the long-term weather patterns of Boulder County. Potential topics may include 30-day weather outlooks, El Nino/La Nina, and seasonal forecasts. You will find less about the day-to-day weather, with more focus on longer trends and patterns.

Colorado’s “Almost” Extreme Heatwave: Here’s What May Save Us (Updated)

July 9, 2026 / BoulderCAST Team / 0 Comments

A powerhouse heat dome is about to sprawl across the entire country, and while Colorado’s Front Range won’t sit dead-center in the bullseye, we’re still in for a long, stubborn stretch of serious heat. Daytime temperatures will soar into the middle 90s to low 100s, with warm nights that barely cool off, and skies so clear you might just forget what a cloud looks like.

A subtle shift in the ridge’s position will save Denver and Boulder from the truly unprecedented temperatures that some weather apps and models were flashing earlier this week — but the stage will be set for a scorching Western Slope, lingering fire concerns, and a delayed monsoon that is just now trying to claw its way north. We break down what’s coming, where the heat will hit hardest, and when relief might finally show up.

June 2026 Graphical Weather Review: Warm, Dry and Smoky — Colorado Feels Effects from the West’s Snow-Starved Winter

July 8, 2026 / BoulderCAST Team / 0 Comments

June 2026 closed out as a parched, smoky, and somewhat warm month across the Front Range, with Boulder seeing almost no meaningful moisture aside from a few late‑month storms — some of which dumped large hail across portions of the Denver Metro area. Day after day, smoke‑laden skies from both distant and eventually in‑state wildfires muted visibility and degraded air quality, a stark reminder of how the West’s exceptionally warm, snow‑deficient winter is now echoing across the region in the form of early‑season fire activity and persistent haze.

Here’s a graphical look at how June 2026 unfolded across Boulder, Denver, and the Front Range — and how it compared to climatology.

This Week in Colorado Weather: July 6, 2026

July 6, 2026 / Andy / 0 Comments

This week several large wildfires will continue to slowly grow across Colorado as smoke remains stubbornly locked over the Front Range, and a heat dome building for the upcoming weekend will be downright punishing. But there is light at the end of the hot and smoky tunnel — the now-delayed 2026 monsoon will make its triumphant return next week. Read on for all the details.

This Week in Colorado Weather: June 29, 2026

June 29, 2026 / Ben Castellani / 0 Comments

The last weekend of June didn’t just sizzle — it erupted. As a powerful early‑summer trough carved into the Great Basin, the Southwest lit up with new fires and thick smoke thanks to some of the most volatile atmospheric conditions we’ve seen this season. Colorado wasn’t spared, either: several fast‑growing fires ignited across the Western Slope and Mountains, sending plumes straight into the Front Range. And with a stubborn dipole pattern locking in place across the nation, the week ahead promises more wind, more dryness, and more smoke — plus a few twists in the forecast you’ll want to keep an eye on. Let’s break down what’s driving this outbreak, what it means for the Boulder–Denver corridor, and when relief may finally arrive.

This Week in Colorado Weather: June 22, 2026

June 22, 2026 / Ben Castellani / 0 Comments

The atmosphere is gearing up for one of those classic late‑June stretches where Colorado tries to run every weather storyline at once. Several days of unusually strong flow aloft, deepening upslope moisture, and a parade of shortwaves are about to collide over the Front Range. The result will be day after day of severe thunderstorms. Add in waves of incoming wildfire smoke and a potentially high‑end fire danger setup by the weekend, and there’s plenty to unpack in this week’s forecast. Let’s take a closer look.

This Week in Colorado Weather: June 15, 2026

June 15, 2026 / Andy / 0 Comments

A western heat dome is gearing up to push the Front Range toward its hottest stretch of the season so far, with downslope winds and fire‑weather concerns building right alongside it. A weak front will try to break the heat later in the week, but largely fail as temperatures rebound into the 90s quickly by Friday and the weekend. As our spring wet season has now come to an end, storm chances remain woefully low throughout the extended leading to further drought intensification statewide.

This Week in Colorado Weather: June 8, 2026

June 8, 2026 / Ben Castellani

Warmth, wind, and a few atmospheric curveballs are lining up for the Front Range this week — and it all starts with a sharp swing from severe storms to hot fire danger in less than 24 hours. From Monday’s hail‑ready instability to mid‑week blow‑dryer conditions and a potential cool‑down lurking on the weekend horizon, this week’s forecast has a little bit of everything. Read on as we detail what to watch as this surprisingly active June pattern unfolds across Colorado.

May 2026 Graphical Weather Review: A Tale of Two Storms — Damaging Snow and a Deluge of Rain Put a Dent in the Drought

June 4, 2026 / BoulderCAST Team

May 2026 delivered a true roller‑coaster pattern along the Front Range. Despite finishing warmer than average, the month was punctuated by two significant chilly precipitation events that funneled a remarkable amount of moisture into Boulder and Larimer Counties. The first arrived as a damaging late‑season snowstorm, wrecking leafed‑out trees across the region, while the second system — fortunately — remained all rain at lower elevations.

Together, these systems provided meaningful drought relief, though the broader hydrological picture across Colorado and the West remains deeply strained. Here’s a graphical look at how May unfolded across Boulder, Denver, and the Front Range — and how it compared to climatology.