Alert archive / Utah / Flash Flood Warnings in 2026

Flash Flood Warning 113, NWS Grand Junction, CO

September 15, 2026San Juan County, Utah

NWS Grand Junction, CO issued this flash flood warning at Sep 15, 2026, 9:58 AM MDT for San Juan County, Utah. 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
Sep 15, 2026, 9:58 AM MDT (15:58 UTC)
Expired
Sep 15, 2026, 1:00 PM MDT
In force
3 hr
Issued by
NWS Grand Junction, CO
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County San Juan County, UT

The radar

The Grand Junction radar (KGJX), 212 km from the middle of the area, began a volume at 16:00 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

Salt Lake City I, UT (KSLC), launched 12:00Z, 4.0 hours before the alert went out and 394 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, Salt Lake City I, UT at 12:00Z on 2026-09-15Temperature 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, Salt Lake City I, UT at 12:00Z on 2026-09-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 40 square meters per square second.1939587897Sfc1 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
2330 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
40 m²/s²
0-3 km storm-relative helicity
157 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The office that day

Everything else NWS Grand Junction, CO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 14, 6:58 PM MDTSpecial Weather StatementGJTMontrose17 min
Sep 14, 7:11 PM MDTSpecial Weather StatementGJTMontrose34 min
Sep 14, 7:31 PM MDTSpecial Weather StatementGJTMontrose29 min
Sep 14, 7:53 PM MDTSevere Thunderstorm WarningGJTDelta, Mesa37 min
Sep 14, 7:57 PM MDTSpecial Weather StatementGJTMontrose33 min
Sep 14, 8:25 PM MDTSpecial Weather StatementGJTMontrose35 min
Sep 14, 10:45 PM MDTAreal Flood AdvisoryGJTMesa2 hr
Sep 15, 1:32 AM MDTSpecial Weather StatementGJTMontezuma28 min
Sep 15, 3:03 AM MDTSpecial Weather StatementGJTLa Plata27 min
Sep 15, 3:29 AM MDTSpecial Weather StatementGJTLa Plata31 min
Sep 15, 4:12 AM MDTSpecial Weather StatementGJTArchuleta33 min
Sep 15, 10:44 AM MDTFlood WatchGJTArchuleta, Dolores, Gunnison, Hinsdale, La Plata, Montezuma and 4 more61 hr
Sep 15, 12:58 PM MDTSpecial Weather StatementGJTMontrose32 min
Sep 15, 1:12 PM MDTSevere Thunderstorm WarningGJTMontrose, Ouray, San Miguel33 min
Sep 15, 2:24 PM MDTFlash Flood WarningGJTGarfield3 hr
Sep 15, 2:42 PM MDTFlash Flood WarningGJTSan Miguel3 hr
Sep 15, 2:53 PM MDTSpecial Weather StatementGJTMesa37 min
Sep 15, 3:41 PM MDTSpecial Weather StatementGJTMesa34 min
Sep 15, 5:50 PM MDTSpecial Weather StatementGJTMesa25 min
Sep 15, 5:55 PM MDTSpecial Weather StatementGJT35 min
Sep 15, 9:49 AM MDTFlash Flood Warning Considerable damage threatGJTSan Juan3 hr
Sep 15, 2:20 PM MDTSevere Thunderstorm WarningGJTSan Juan25 min
Sep 15, 3:09 PM MDTSpecial Weather StatementGJTSan Juan36 min
Sep 15, 5:30 PM MDTSpecial Weather StatementGJTGrand30 min
Sep 15, 5:31 PM MDTFlash Flood WarningGJTGrand4 hr
Sep 15, 5:51 PM MDTFlash Flood WarningGJTGrand3 hr
Sep 15, 5:57 PM MDTSpecial Weather StatementGJTGrand33 min

Nearby

Flash Flood Warnings in Utah, 2026Every flash flood warning in 2026

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.