A broad, slow‑moving heat dome has settled over the West, delivering a run of persistent October warmth to the Front Range — but this quiet, summerlike stretch won’t hold forever. This week will be defined by record‑challenging heat aided by downslope flow, and only the faintest chances for a few stray rain showers before a major pattern shake‑up arrives early next week. Ensemble guidance hints at everything from long‑awaited rainfall to the season’s first frost, with even a few early‑season snow scenarios lurking in the spread. Read on for all the details.
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A slow‑moving, high‑stakes storm has been creeping toward Colorado all week — a rare mash‑up of an autumn upper‑low and the juicy tropical remnants of Hurricane Polo — and for a moment, it looked like Boulder and Denver might finally score a true soaking. But as the atmosphere loves to do, the script flipped late. Today’s update breaks down how this once‑promising setup unraveled over the last couple days, why southern Colorado is now squarely in the bullseye, and what scraps of moisture the Front Range can still squeeze out as the system passes by to our south.
A slow‑building, tropical‑charged system is about to make its move on Colorado — and the setup behind it is far more complex than your typical late‑September storm. As Hurricane Polo’s remnants collide with a impressive Pacific upper‑low, the stage is set for a rare, moisture‑laden system that could deliver anything from a major rain event to a near‑miss for Boulder and Denver. We break down why the models are struggling, what the key track differences mean for your neighborhood, and where flooding and high‑elevation snow may become real concerns as the storm unfolds.
UPDATED Tuesday Sep 26 5:00PM: Updated rainfall forecast map and some wording to account for growing confidence the bulk of the storm will miss the Denver Metro area.
A complicated weather pattern is taking shape across Colorado this week, with a deep low pressure system, a surge of tropical moisture, and the remnants of Hurricane Polo all getting tangled up together. For Boulder, Denver and the Front Range, that combination creates some unusually large forecast uncertainties — particularly when it comes to how much rain falls and just how chilly things get by midweek. Meanwhile, southern Colorado is in store for a much bigger soaking, with some impressive rainfall totals showing up in the guidance alongside high peak snowfall. We break down what we know now, what remains uncertain, and when we can finally expect this week’s definitively gloomy weather to break and sunshine to return.
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