I live in the neighborhood, but we are just outside of the evacuation zone. This part of Colorado is — in other times — a really nice mixed-use set of communities. It has a lot of open fields, farms, businesses, and “old town” town centers right alongside very dense apartment buildings and single family homes. We haven’t had snow or rain in almost two months, and everything is very dry. I saw the wind bringing flames along these open fields (like kindling) right into Louisville and Superior, and then it lights up the neighborhood, spreading house to house, fueled by wind that has brought down trees and power lines (friends in Boulder getting some rolling blackouts earlier). These nice parks and open fields are like turbo boosts from neighborhood to neighborhood. Any other combination - not as dry, not as windy, and it would have been a small localized fire. Everyone is packing their cars even if outside of the mandatory or pre-evacuation zones. We are supposed to have a massive snowstorm tomorrow morning as well, which makes this very painful - large fires normally burn in loosely populated areas, but this is as dense as any major suburban center.
> Any other combination - not as dry, not as windy, and it would have been a small localized fire.
If what I heard was correct and they're having 110 mph wind gusts, any fire is likely to spread, even in a neighborhood. I agree the open space makes it spread even faster, but with that kind of wind, fire reaches a new level of destruction.
My house probably burned, we’ll find out in the morning. Family is safe, got out in time and we have a place to stay, so blessed in that regard.
We just moved from the Bay Area last year. This isn’t an area in the wilderness, it’s suburbia. This would be like if 600 homes on the edge of Fremont or San Jose burned.
Freak situation where we haven’t had rain in 3 months, winds were super high, temps were high for Dec, and it sounds like power lines went down. Unreal.
I live just south of Superior. Let me know if you need a place to stay and I can assist.
My area has just been removed from the pre-evacuation zone, since the winds have finally subsided.
For anyone that doesn't live here, this was caused by Chinook winds that were stronger than usual combined with extremely dry air and vegetation. My specific location had 115 mph gusts today. When you live here you get used to the Chinooks but today was extreme. Entire house was shaking.
To add color to the comment above, it is indeed an extremely suburban area. The fire started on Marshall Mesa, which is a popular mountain biking trail. Notably if you go east from Marshall Mesa you suddenly hit a shopping center with a Costco and a Target. The fire went east and directly into the shopping center along with all of the homes clustered in the neighborhoods around it. Terrible, and with very little warning.
I hope your house is okay. I'm very glad your family is safe.
The last fire came within five miles of Cupertino and people I know that live near to 280/Rancho San Antonio got evacuation warnings before the wind turned.
It's only a matter of time before Los Gatos, Saratoga, Almaden, etc suffer major fire damage. CalFire defensible space recommendations are largely ignored.
I don’t believe danger is imminent but it is incredible how close this fire is to the former Rocky Flats.
This is the second time in as many years I’ve been surprised to see fires close enough to be viewed from the front yard - in exact opposite directions.
I’m at the N Boulder rec center with my partner (a reporter) covering this for the NYT. Thankfully it seems quiet and the wind is dying down.
I live west of Rocky Flats. I actually walked onto the now refuge that surrounds the plant tonight and took photos of the fires in the distance.
It should be noted that the contaminated areas of Rocky flats are extremely secure and buried under massively overbuilt layers of concrete containments. The EPA milked the site for super fund money for probably a decade longer than it needed to for the cleanup. If you're wondering how I know this it's because I have several neighbors who used to work at the plant and then worked on the EPA-led cleanup when it was a super fund site.
The remediation started in 1997, and ended in 2006, so I'm not sure how it could have lasted an extra decade given that it didn't last an entire decade total. And that was using only $7B of the original estimate of $35B.
There's not an increased rate of cancer around the area. People have lived in this area for a long time. My neighborhood is upwind not downwind. There's no increased cancer cluster anywhere downwind of the site.
The data should be driving these decisions instead of the paranoia of anti-nuke idiots.
Context: Rocky Flats, Colorado, is the site of the former Rocky Flats Weapons Plant, a manufacturing facility for US nuclear weapons, and since the 1990s, a major environmental contamination and cleanup site.
Though much radioactive material was removed (including 21 tons of weapons-grade material), concerns over residual radioactive contamination being made airborne through fire or other disturbance remain.
Didn’t they confirm over 600 homes burned? And the entire towns of Louisville and Superior evacuated (as well as a big hospital - Avista). That seems dangerous to me!
I am in Boulder too and I think the comment means, imminent in Boulder proper. But you are of course right, this is a horrifying thing happening right now for many people just a few miles away.
I meant imminent to the Rocky Flats area. Of course all the buildings were razed, but I would assume it wouldn't be a Good Thing for that place to also be on fire.
Eh, the place that built the subdivision sues the crap out of anyone that tries to get more testing done. And there's a lot of methodological issues with the tests that they do have. Like using gamma radiation tests for plutonium contamination (plutonium is primarily an alpha emitter as it decays).
Also the fuckers had the audacity to name the subdivision 'Candelas'. For those following along at home, Rocky Flats was a plutonium warhead manufacturing facility raided by the feds back in the day for doing crazy stuff like lighting plutonium on fire, and not coming anywhere near close to what would be expected for storing contaminated materials. It then became one of the first super fund sites.
I think the issue is how well remediated it’s actually is. I presume that there are a reasonable number of people who doubt that the remediation was actually complete enough to be safe against wild fires
The remediations are massive concrete structures covering large swaths of the ground. A brush fire being pushed by heavy winds isn't going to do anything to it.
Additionally the large subdivision was not built on the site but surrounding the perimeter to the site. The core site is off limits to anyone as a precaution to prevent anyone from tampering with the remediations or deliberately vandalizing them.
Surrounding the core site is a wildlife refuge that is fairly large. On the outside of this refuge is the subdivision.
Sounds like the same thing that happened in Santa Rosa in 2017 and Talent in 2020: Drought, wind, downed power lines. I live near Talent, and while I didn't lose my home it was one of the worst things I've ever lived through.
If anyone from this area wants to talk, I'm game. Email's in my profile.
I'm from this area and still live close enough that I can see the smoke. We have been experiencing a drought, seeing temperatures reaching almost 70 in December, and broke the record this year for latest first snow fall. These fires started in the late morning possibly from a downed power line and by the early afternoon had spread rapidly. Hundreds of structures including entire subdivisions have burned to the ground without hours. If you're feeling generous, please consider making a donation at the link below.
In Florida now but I live in NW Arvada, watching updates in horror, but didn’t they say winds were over 100 mph too? Add that to the cocktail you describe above, and boom.
I also live in Northwest Arvada and we had 115 mph winds today. My coworkers were hearing my house rattle when I was on a call today.
If your house is close to 93 and 72 you probably have a ton of debris in your yard.
The Chinook winds were the worst I've seen. When I heard there were fires I knew it was going to be bad. But I couldn't imagine that it was going to burn down entire shopping centers.
Per the government briefing a couple hours ago, over 500 structures (which are mostly homes) have burned down. That number is likely higher now. Absolutely devastating.
Driven by high winds into dense housing - those elements remind me
of a 2017 fire that burned over 2,500 homes in Santa Rosa, California: https://en.wikipedia.org/wiki/Tubbs_Fire
FIRMS Fire Map allows you to interactively browse the full archive of global active fire detections from MODIS and VIIRS. Near real-time fire data are available within approximately 3 hours of satellite overpass and imagery within 4-5 hours.
DO NOT USE FOR EMERGENCY PLANNING OR RESPONSE. Data are not realtime, and local authorities should be given precedence.
I'm wondering if fire-prone areas should be zoned to require fireproof building. No more wood homes/roofs. Europe generally doesn't use wood home construction, so doesn't seem crazy
I think you might be getting downvoted for "fireproof" which sounds absolute, and is probably not realistic. But you're right that regulations should evolve to require responsible home design and maintenance in fire-prone areas!
If you want to understand wildfires, read everything he's written. He's basically the single handed Mythbusters of wildfire understanding, and has done things like "instrumented crown fires of test stands" to better understand radiant heat flux from actual fires.
I’m not an expert in the matter, but I’ve heard that modern wood frames are just as good as steel frames. If the fire is close and strong enough to ignite a wood stud, the steel stud would already fail. Though would love input from an expert here.
Yeah failure from heat is one thing, but another is how quickly the structure catches fire or spreads it. Another commenter linked the 99PI piece how they found out that embers were getting through vents in roofs (you need those vents because your house is a weird little ecosystem) and catching the inside of the roof on fire. And if the outside is made of wood, it's more likely to catch than, say, concrete or brick.
The material you're more likely to use for a home if it's not wood is concrete or brick with some steel added. Concrete and brick are very fire resistant, which would make it much harder for a building to catch, and so harder for fire to spread if the building doesn't catch. The reason our homes in the US aren't brick (anymore) is it's a very expensive/specialized job, but wood framing is easy in comparison and wood is cheap here (and we have a lot of lumber mills to churn out small standardized pieces)
The inside would of course burn eventually if engulfed in a slow-moving fire with plenty of fuel, because things ignite when they get hot enough (or turn to charcoal if there's not enough oxygen). But if you're lucky the fire will move past quickly or run out of fuel, so every little advantage helps.
Not an expert, but have done a lot of reading and some writing on wildfires, fire resistant structures, etc. I live on a hill that catches fire rather more often than I really enjoy and spend a lot of my spring cutting firebreaks.
Any sort of structure, wood or not, will withstand a huge radiant flux of energy before catching fire. Well, well beyond what will crispy fry a human, the siding may be charred, but it won't burn. Even wood siding tolerates a lot.
What lights houses on fire are firebrands - "burning crap from the sky." Trees, mostly, embers, other houses... that's what catches things. Typically it will light some small stuff near the house first, or in the corners of the roof (pine needles are a common enough fuel source). At that point, you've got a far harder problem - direct flame impingement. If you get to that point, you are usually screwed.
You can build fireproof roofs - I fully support pretty much anything in any areas requiring a Class A fireproof roof, which doesn't really mean much more than "being careful what you build, and not using wood shake." An asphalt shingle roof can often be Class A fireproof, and that tolerates a 2' x 2' bit of burning brand on the roof without burnthrough. The roof may not be in great shape, but an awful lot of "stuff on fire" can land on it, and if it's a properly constructed Class A roof, it won't penetrate to the building.
The landscaping around the building is a harder problem. Within 30' or so, it generally has to "not burn." This can be from design, or from sprinklers, or... whatever. If the landscaping within 30' of a house is on fire, the house is likely to follow. If you keep that from lighting, the house stands a pretty good chance.
... yes, this means that in suburbia, if the house next door is on fire, you're screwed. Don't live in such tightly packed spaces.
The next major problem are windows. If they fail, the house usually goes. They tolerate a lot, but in high wind storms, random debris can break the window, and then firebrands get in. Whoops. I would like to see some good studies on shutters, because they seem like the sort of thing that will make a very real difference on window breakage in storms, but they're not a thing anymore and probably won't come back.
But look at the debris patterns when you find the news articles of the burned out neighborhoods. Almost always, you'll see intact lawns and vegetation around a burned out foundation. It's not a "wall of flame" marching through the neighborhood - it's the firebrands, blown by the wind, that you have to defend against.
Unfortunately, when it comes to wildfires, when you've got things like 80 gusting 100, you're also just screwed. :/
I've heard roof vents are good at sucking the burning embers into the attic. I believe they make shutters for roof vents for this reason but I don't know for sure. Going through the big San Diego fires was definitely a lesson in taking defensible space seriously and appreciating the threat of burning embers.
> I would like to see some good studies on shutters, because they seem like the sort of thing that will make a very real difference on window breakage in storms, but they're not a thing anymore and probably won't come back.
Having grown up in hurricane land, this statement stood out to me. Why did shutters go away? Why won't they come back?
I have thoughts, but I'd really like to see some solid information on how prevalent they were, what their previous rationale was, and what accounts for their decline.
On contemporary houses, if shutters exist at all, they're all but entirely decorative. Frequently they're on the inside of a house.
In hurricane-prone regions, shutters seem as if they'd make more sense than repeatedly boarding-up and unboarding windows.
Note that in the case of wildfire, embers entering into attic and crawlspace areas is a larger threat than direct radiant-heat compromise of windows, though ignition of interior furnishings (especially curtains or blinds) by radiant heat does occur. Still, window and other structure penetration shutters seem as if they'd be a potentially useful addition.
It's more the point that studs are not the key failure point of structures in the event of a fire. It's not that your studs are igniting and burning down the structure from inside the walls. It's that other structural elements are becoming engaged. Attic and crawlspaces especially, though also often porches, patios, and other extensions.
See this IBHS wildfire structure ember test video:
This is, incidentally, a key issue in risk management: risk profiles and threat models are not a constant. The model is a reflection of reality, and if reality changes, the model should change with it.
This is horrible. I hope everyone is OK. Homes can be rebuilt. Life is what matters.
About three years ago I had to do a bunch of research on fire resistant construction for a project. I came across something that is fantastic. Part of me doesn't understand why this isn't a requirement in fire-prone areas, if not every home and building.
This is the product we used, of course, there are other manufacturers.
No affiliation at all other than being a customer. Yes, we conducted our own tests before making the decision.
It won't resist flames forever, but it absolutely delays the maximal burn event. In addition to this, it provides a potentially significant delay of the spread from structure to structure, particularly if the gap between structures is reasonable (say, 10 ft or more).
In speaking to LA County permit authorities I learned that one of the problems using advanced technology is that the bureaucracy of the system gets in the way. It's truly sad. The way the engineers put it to me translates to: If we don't have a checkbox, you can't use it. Seriously.
The only way to use it is for YOU to foot the bill and pay to conduct all the tests required to add the product to the approved materials list. This process, again, due to the bureaucracy, could take years. And, BTW, much as is the case with a lot of things in the US, obtaining approval in one county does not automatically allow someone to use it outside that county. Sometimes I think the US is a bunch of independent little kingdoms, much more so than a country.
In our case we could not obtain approval because the material was not on the list. We provided tons of proof, even getting the CEO's of various intumescent coating companies involved. The approvals are very weird, for example, a product might be approved for outdoor use and not approved for indoor applications. No, not because it won't work or is toxic. More often than not it is because the tests were not conducted for that particular application and you are out of luck. You might be approved to paint your walls with this stuff but are not allowed to coat your framing, rafters, etc. with it. Crazy.
We ended-up working around these barriers because this was a DoD project. They simply pulled rank and that was that.
It's not any one thing. Warm. Dry, still no snow (or rain). High winds, 115mph @ Rocky Flats, 75+ in Boulder, and a power cable downed by wind that started the fire, high density housing made from highly flammable materials...
Lifelong Boulderite here. No snow on the ground is very typical during winter. If it does snow, it often doesn't stick around for very long since Colorado gets a lot of sunshine. However, it has still been unusually dry. Fires have been getting worse and worse every year, but always during the summer and fall months. I've never seen anything like this during winter in my whole life.
Thanks- my wife went to Fort Collins and talked about it always being sunny and nice between snows, but I didn't realize the ground cleared completely; I figured it would be too cold for that (another frequent component to her stories :) )
The overall dryness is not normal, but Denver/Boulder does not generally have snow on the ground consistently in winter. (Up in the mountains is obviously a different story).
The joke in Denver is sometimes that the city's snow plowing plan for the sidestreets appears to be "wait for it to melt" ....which works most of the time. Even in January the average day is over 45F, which combined with the sunny climate often makes short work of snow.
We've gotten snow, and it's not unusual for 5000ft to not have snow right now (that's even lower elevation than boulder proper), but it's way less total snow than we normally have gotten by now. That being said, it's also pretty normal for a la nina year to be light on precipitation early in the winter, and we get it all during the spring.