Alert archive / Colorado / Flash Flood Warnings in 2023

Flash Flood Warning 58, NWS Denver/Boulder, CO

July 15, 2023Larimer County, Colorado

NWS Denver/Boulder, CO issued this flash flood warning at Jul 15, 2023, 3:57 PM MDT for Larimer County, Colorado. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 15, 2023, 3:57 PM MDT (21:57 UTC)
Expired
Jul 15, 2023, 6:48 PM MDT
In force
3 hr
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Flood severity
None

County Larimer County, CO

The radar

The Cheyenne radar (KCYS), 77 km from the middle of the area, began a volume at 21:59 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

Grand Junction, CO (KGJT), launched 12:00Z, 10.0 hours before the alert went out and 310 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.

Skew-T log-pSkew-T log-p diagram, Grand Junction, CO at 12:00Z on 2023-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Grand Junction, CO at 12:00Z on 2023-07-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -55 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3100 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
-55 m²/s²
0-3 km storm-relative helicity
45 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 14, 6:14 PM MDTSpecial Weather StatementBOUWeld31 min
Jul 14, 6:51 PM MDTSpecial Weather StatementBOUWeld24 min
Jul 14, 7:15 PM MDTSpecial Weather StatementBOUMorgan30 min
Jul 14, 7:44 PM MDTSpecial Weather StatementBOUMorgan31 min
Jul 14, 9:33 PM MDTSpecial Weather StatementBOUDenver42 min
Jul 15, 9:06 AM MDTSpecial Weather StatementBOUMorgan39 min
Jul 15, 1:30 PM MDTSpecial Weather StatementBOUDouglas30 min
Jul 15, 2:10 PM MDTSevere Thunderstorm WarningBOUWeld35 min
Jul 15, 2:17 PM MDTHeat AdvisoryBOUAdams, Arapahoe, Boulder, Broomfield, Denver, Douglas and 3 more54 hr
Jul 15, 2:44 PM MDTSevere Thunderstorm WarningBOUWeld15 min
Jul 15, 3:32 PM MDTSevere Thunderstorm WarningBOULarimer28 min
Jul 15, 3:44 PM MDTAreal Flood AdvisoryBOULarimer27 min
Jul 15, 3:46 PM MDTSevere Thunderstorm WarningBOULarimer29 min
Jul 15, 4:07 PM MDTSpecial Weather StatementBOULarimer38 min
Jul 15, 4:11 PM MDTSevere Thunderstorm WarningBOUBoulder, Larimer23 min
Jul 15, 4:12 PM MDTSevere Thunderstorm WarningBOULarimer, Weld33 min
Jul 15, 4:46 PM MDTSevere Thunderstorm WarningBOUBoulder29 min
Jul 15, 5:07 PM MDTSpecial Weather StatementBOUBroomfield23 min

Nearby

Flash Flood Warnings in Colorado, 2023Every flash flood warning in 2023

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.