Alert archive / Colorado / Flash Flood Warnings in 2021
Flash Flood Warning 75, NWS Grand Junction, CO
NWS Grand Junction, CO issued this flash flood warning at Aug 3, 2021, 12:16 PM MDT for San Miguel County, Colorado. It was in force for 88 min. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Aug 3, 2021, 12:16 PM MDT (18:16 UTC)
- Expired
- Aug 3, 2021, 1:44 PM MDT
- In force
- 88 min
- Issued by
- NWS Grand Junction, CO
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Flood severity
- None
County San Miguel County, CO
The radar
The Grand Junction radar (KGJX), 122 km from the middle of the area, began a volume at 18:16 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, 6.3 hours before the alert went out and 135 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
- 5 J/kg
- Mixed-layer CIN
- -176 J/kg
- Mixed-layer LCL
- 1792 m above ground
- 0-6 km bulk shear
- 6 kt
- 0-1 km storm-relative helicity
- -5 m²/s²
- 0-3 km storm-relative helicity
- 48 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
120
WGUS55 KGJT 031816
FFWGJT
COC113-032115-
/O.NEW.KGJT.FF.W.0075.210803T1816Z-210803T2115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Grand Junction CO
1216 PM MDT Tue Aug 3 2021
The National Weather Service in Grand Junction has issued a
* Flash Flood Warning for...
East Central San Miguel County in southwestern Colorado...
* Until 315 PM MDT.
* At 1216 PM MDT, Doppler radar indicated training storms producing
heavy rain across the warned area. Roughly 0.5 inches of rain has
fallen within the last half hour. Additional rainfall amounts of
0.5 to 1 inch are possible in the warned area within the next
hour. Flash flooding is ongoing or expected to begin shortly.
HAZARD...Life threatening flash flooding. Thunderstorms
producing flash flooding.
SOURCE...Radar.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets and underpasses.
* Some locations that will experience flash flooding include...
Sawpit and Fall Creek.
This includes the following highways...
Colorado 145 between mile markers 76 and 84.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be aware of your surroundings and do not drive on flooded roads.
In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.
&&
LAT...LON 3802 10806 3803 10805 3802 10799 3801 10796
3799 10792 3796 10793 3793 10796 3792 10798
3792 10800 3796 10803 3796 10806 3798 10807
3800 10807
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
ERW1 follow-up statement
502
WGUS75 KGJT 031944
FFSGJT
Flash Flood Statement
National Weather Service Grand Junction CO
144 PM MDT Tue Aug 3 2021
COC113-031954-
/O.CAN.KGJT.FF.W.0075.000000T0000Z-210803T2115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Miguel CO-
144 PM MDT Tue Aug 3 2021
...FLASH FLOOD WARNING IS CANCELLED FOR EAST CENTRAL SAN MIGUEL
COUNTY...
At 130 pm... San Miguel County law enforcement reported no flooding
on Highway 145. The heavy rain has ended for the time being.
Flooding is no longer expected to pose a threat.
A Flash Flood Watch remains in effect until 1200 AM MDT Wednesday
for portions of northwest Colorado, southwest Colorado and west
central Colorado.
LAT...LON 3802 10806 3803 10805 3802 10799 3801 10796
3799 10792 3796 10793 3793 10796 3792 10798
3792 10800 3796 10803 3796 10806 3798 10807
3800 10807
$$
BWMThe office that day
Everything else NWS Grand Junction, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 2, 6:41 PM MDT | Special Weather Statement | GJT | 49 min | |
| Aug 2, 7:44 PM MDT | Areal Flood Advisory | GJT | Garfield, Mesa | 2 hr |
| Aug 2, 8:21 PM MDT | Areal Flood Advisory | GJT | Mesa | 114 min |
| Aug 2, 8:27 PM MDT | Flash Flood Warning | GJT | Eagle, Garfield | 2 hr |
| Aug 2, 8:43 PM MDT | Flash Flood Warning | GJT | Garfield, Mesa | 2 hr |
| Aug 3, 9:32 AM MDT | Areal Flood Advisory | GJT | Eagle | 3 hr |
| Aug 3, 2:54 PM MDT | Flash Flood Warning | GJT | Eagle, Garfield | 111 min |
| Aug 3, 3:21 PM MDT | Flash Flood Warning | GJT | San Miguel | 104 min |
| Aug 3, 3:27 PM MDT | Flash Flood Warning | GJT | Eagle, Garfield, Pitkin | 2 hr |
| Aug 3, 4:04 PM MDT | Special Weather Statement | GJT | San Miguel | 41 min |
Nearby
Flash Flood Warnings in Colorado, 2021Every flash flood warning 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.