Alert archive / Colorado / Dense Fog Advisories in 2021
Dense Fog Advisory 5, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this dense fog advisory at May 24, 2021, 6:23 AM MDT for 8 counties in Colorado. It was in force for 3 hr.
The area
The counties it named.
The facts
- Issued
- May 24, 2021, 6:23 AM MDT (12:23 UTC)
- Expired
- May 24, 2021, 9:00 AM MDT
- In force
- 3 hr
- Issued by
- NWS Denver/Boulder, CO
Counties Elbert County, CO, Lincoln County, CO, Logan County, CO, Morgan County, CO, Phillips County, CO, Sedgwick County, CO, Washington County, CO, Weld County, CO
The radar
The Denver radar (KFTG), 109 km from the middle of the area, began a volume at 12:26 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
N. Platte/Lee Bi, NE (KLBF), launched 12:00Z, 0.4 hours before the alert went out and 257 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1599 m above ground
- 0-6 km bulk shear
- 60 kt
- 0-1 km storm-relative helicity
- -95 m²/s²
- 0-3 km storm-relative helicity
- 111 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
What forecasters said that day
The local office's own words before this dense fog advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Denver/Boulder, CO wrote its last area forecast discussion before this dense fog advisory went out at May 23, 3:19 PM MDT, 15 hours 4 minutes earlier.
Area forecast discussion, May 23, 3:19 PM MDT, 15 hours 4 minutes before
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</html>Hazardous weather outlook, May 23, 11:14 AM MDT, 19 hours 9 minutes before
Hazardous Weather Outlook National Weather Service Denver/Boulder CO 1114 AM MDT Sun May 23 2021 COZ030>051-241715- Jackson County Below 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- Grand and Summit Counties Below 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Larimer and Boulder Counties Between 6000 and 9000 Feet- Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear Creek/Northeast Park Counties Below 9000 Feet- Central and Southeast Park County- Larimer County Below 6000 Feet/Northwest Weld County- Boulder And Jefferson Counties Below 6000 Feet/West Broomfield County- North Douglas County Below 6000 Feet/Denver/West Adams and Arapahoe Counties/East Broomfield County- Elbert/Central and East Douglas Counties Above 6000 Feet- Northeast Weld County-Central and South Weld County-Morgan County- Central and East Adams and Arapahoe Counties- North and Northeast Elbert County Below 6000 Feet/North Lincoln County- Southeast Elbert County Below 6000 Feet/South Lincoln County- Logan County-Washington County-Sedgwick County-Phillips County- 1114 AM MDT Sun May 23 2021 ...SEVERE THUNDERSTORMS WITH A FEW TORNADOES EXPECTED ACROSS NORTHEAST COLORADO... This hazardous weather outlook is for northeast and north central Colorado. .DAY ONE...This Afternoon and Tonight Severe thunderstorms with large hail, damaging winds, and a few tornadoes are expected across northeast Colorado this afternoon and early evening. The dryline has been slow to push eastward, and thus the severe weather threat has shifted further west. While a few showers and storms will occur over the Front Range and I-25 Corridor, the highest threat of severe storms today will be east of a line from Cheyenne, Wyoming to around Greeley and then southward to near Denver International Airport and Kiowa. Large hail up to golfball sized hail and damaging winds up to 70 mph can be expected from most severe storms, while a couple storms will be capable of producing longer track tornadoes and baseball sized hail. Drier conditions and gusty southwest winds will develop from west to east across the mountains and I-25 Corridor later this afternoon, behind the above mentioned dryline. Storms will be ending from west to east, exiting the far northeast corner of the state around 7 or 8 pm. .DAYS TWO THROUGH SEVEN...Monday through Saturday Monday through early Wednesday will be drier with near normal temperatures, then expect an increasing threat of afternoon and evening storms Wednesday afternoon and Thursday, especially across the northeast plains. Drier again with only a slight chance of late day storms for the Friday through Saturday period. Temperatures will be above normal with readings around 80 degrees. .SPOTTER INFORMATION STATEMENT... Spotter activation will be required across the plains by noon.
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 23, 6:19 PM MDT | Severe Thunderstorm Warning | BOU | Phillips, Sedgwick | 41 min |
Nearby
Dense Fog Advisories in Colorado, 2021Every dense fog advisory in 2021
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.