Alert archive / Utah / Flash Flood Warnings in 2021
Flash Flood Warning 59, NWS Grand Junction, CO
NWS Grand Junction, CO issued this flash flood warning at Jul 29, 2021, 6:17 PM 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 outline as issued.
The facts
- Issued
- Jul 29, 2021, 6:17 PM MDT (00:17 UTC)
- Expired
- Jul 29, 2021, 9:30 PM MDT
- In force
- 3 hr
- Issued by
- NWS Grand Junction, CO
- Area
- Storm-based polygon
- Flood severity
- None
County San Juan County, UT
The radar
The Grand Junction radar (KGJX), 225 km from the middle of the area, began a volume at 00:17 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 00:00Z, 0.3 hours before the alert went out and 222 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
- 407 J/kg
- Mixed-layer CIN
- -168 J/kg
- Mixed-layer LCL
- 2854 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- -17 m²/s²
- 0-3 km storm-relative helicity
- 43 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
135
WGUS55 KGJT 300017
FFWGJT
UTC037-300330-
/O.NEW.KGJT.FF.W.0059.210730T0017Z-210730T0330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Grand Junction CO
617 PM MDT Thu Jul 29 2021
The National Weather Service in Grand Junction has issued a
* Flash Flood Warning for...
Southeastern San Juan County in southeastern Utah...
* Until 930 PM MDT.
* At 617 PM MDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. The expected rainfall rate is
0.8 to 1.3 inches in 1 hour. Flash flooding is ongoing or expected
to begin shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flash flooding of small creeks and streams, urban
areas, highways, streets and underpasses as well as
other poor drainage and low-lying areas.
* Some locations that will experience flash flooding include...
Bluff, Montezuma Creek and Tselakai Dezza.
This includes the following highways...
Utah 162 between mile markers 0 and 14.
U.S. Highway 191 in Utah between mile markers 23 and 32.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 3723 10933 3722 10943 3726 10961 3739 10954
3730 10928
FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...0.8-1.3 INCHES IN 1 HOUR
$$
NL1 follow-up statement
907
WGUS75 KGJT 300328
FFSGJT
Flash Flood Statement
National Weather Service Grand Junction CO
928 PM MDT Thu Jul 29 2021
UTC037-300338-
/O.EXP.KGJT.FF.W.0059.000000T0000Z-210730T0330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
San Juan UT-
928 PM MDT Thu Jul 29 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 930 PM MDT THIS EVENING FOR
SOUTHEASTERN SAN JUAN COUNTY...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.
A Flash Flood Watch remains in effect until 1200 AM MDT for portions
of east central Utah and southeast Utah.
LAT...LON 3723 10933 3722 10943 3726 10961 3739 10954
3730 10928
$$
JDCThe office that day
Everything else NWS Grand Junction, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 29, 6:31 PM MDT | Special Weather Statement | GJT | Grand | 44 min |
| Jul 29, 6:34 PM MDT | Areal Flood Advisory | GJT | San Juan | 3 hr |
| Jul 29, 6:53 PM MDT | Areal Flood Advisory | GJT | San Juan | 3 hr |
| Jul 29, 7:41 PM MDT | Areal Flood Advisory | GJT | Grand, San Juan | 3 hr |
| Jul 29, 7:44 PM MDT | Areal Flood Advisory | GJT | San Juan | 3 hr |
| Jul 29, 11:49 PM MDT | Special Weather Statement | GJT | Uintah | 41 min |
| Jul 30, 2:23 PM MDT | Special Weather Statement | GJT | Uintah | 52 min |
Nearby
Flash Flood Warnings in Utah, 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.