Moderate Extreme Weather ● Active
Dense Fog Advisory issued October 27 at 1:20AM MDT until October 27 at 9:00AM MDT by NWS Denver CO, United States of America
Loading live data… · Marker positions are approximate; severity is labelled in each popup. Sources: USGS, GDACS, NASA EONET, NOAA/NWS, EMSC.
* WHAT...Visibility one quarter mile or less in dense fog.
* WHERE...Fort Collins, Boulder and the western suburbs of Denver,
Denver, Briggsdale, Greeley, Fort Morgan, and Byers.
* WHEN...Until 9 AM MDT this morning.
* IMPACTS...Low visibility could make driving conditions hazardous.
Measurements
| Coordinates | 39.9645, -100.8105 |
|---|---|
| Region | Larimer County Below 6000 Feet/Northwest Weld County; Boulder And Jefferson Counties Below 6000 Feet/West Broomfield County; North Douglas County Below 600 |
| Location Precision | country |
| Issuing Authority | United States of America — us-noaa-nws-en |
| Cap Urgency | Expected |
| Cap Certainty | Likely |
| Cap Expires | 2026-10-27T09:00:00-06:00 |
Official source
Warnings courtesy of the issuing national meteorological service, via the WMO Alert Hub.
This is an official warning issued by the authority named above. Follow its instructions and those of your local emergency services.
Severity as published by WMO Alert Hub (national weather services).
View original reportAlso reported by: WMO
This event as JSON · API and licence
Source updated 55 minutes ago (Oct 27, 2026 07:21 UTC) · we last heard from WMO Alert Hub (national weather services) 57 seconds ago
On a slow connection? Low-bandwidth version — no map, no scripts, under 14 KB.
About this location
The agency did not publish coordinates for this warning. The pin is the centre of the country, not the location of the event — read the area name, not the map, for where it applies.
Area as the agency stated it: Larimer County Below 6000 Feet/Northwest Weld County; Boulder And Jefferson Counties Below 6000 Feet/West Broomfield County; North Douglas County Below 600
Official authorities in United States
If you are there, these are the bodies whose instructions apply. This site is not an emergency service and does not issue warnings.
More for United States →What to do
Follow the instructions issued by WMO Alert Hub (national weather services) and your local emergency services. The guidance below is background.
When thunder roars, go indoors — lightning risk outdoors, in vehicles, and first aid for strike victims.
Open Lightning Safety Guide →Earlier extreme weather events in United States
Severe and extreme events of the same kind, before this one. Listed for scale, not because they are connected to it.
Nearby & related events
Disclaimer: figures are automatic feeds from the named agencies and may be revised. Do not use this page for life-safety decisions — follow official local emergency services.