u/WaywardTopo

With multiple large wildfires burning across Colorado right now, I've been digging into the satellite and weather data behind the Gold Mountain Fire near Ouray to try to understand what's actually driving its behavior.

A few things stood out from the instrumental data: Silver Jack RAWS station recorded minimum relative humidity values of 9% on July 3rd — critically dry by any measure. Wind gusts correlate strongly with the largest daily fire growth days. And the NOAA Climate Prediction Center is giving greater than 70% probability of above-normal temperatures through mid-July across the Central Rockies, while the monsoon signal that appeared in last week's long range outlook has largely faded from this week's.

The NWS Grand Junction forecast discussion from yesterday is pretty sobering — moisture arriving next week is expected to stay in the mid-levels rather than reaching the surface, raising the threat of dry lightning rather than meaningful precipitation relief.

I put together a video walking through the Sentinel-2 satellite imagery, VIIRS hotspot progression, slope angle terrain analysis, and the weather data if anyone wants a deeper look at what the landscape and atmospheric picture looks like right now.

https://youtu.be/a56pcYwXJV0

I'm a geologist not a meteorologist or fire specialist — happy to discuss the data or answer questions in the comments.

Like many in Colorado, I've been watching the Aspen Acres Fire explode over the past few days and wanted to understand the terrain driving it. I mapped the latest VIIRS satellite hotspot progression and Sentinel-2 infrared imagery in CalTopo and Google Earth to visualize how the fire is interacting with older burn scars and the enormous elevation range it's burning through — from 5,500 feet up to nearly 11,000 feet.

A few visual breakdowns in the link for anyone interested in the topography and satellite data behind this fire's rapid growth.

Thinking of everyone affected. Stay safe out there.

Link: https://www.youtube.com/watch?v=EPLOerh-4DU

(Disclosure: This is my YouTube channel)

In the early 1950s, the United States Geological Survey and Atomic Energy Commission conducted radiometric mapping across parts of the American West during regional investigations of uranium and thorium occurrences.

In western Colorado, a thorium-bearing occurrence was documented and mapped as part of these early Cold War-era exploration programs, with survey results published in USGS and AEC reports from the period.

The work is tied to a broader set of radiometric mapping efforts that combined ground observations with regional geological interpretation to define anomalous zones across complex volcanic and intrusive terrain.

A short field overview with historical context is available here for reference:
https://youtu.be/BuDDUJBB4Ds?si=FdVCvDlw2iUKRYBp

How much do weathering, cover, and exposure variability affect radiometric signatures in legacy surveys? Curious if others have encountered similar challenges reconciling old data with modern field observations.