Alert archive / Arizona / Flash Flood Watches in 2021
Flash Flood Watch 9, NWS Las Vegas, NV
NWS Las Vegas, NV issued this flash flood watch at Aug 18, 2021, 11:40 AM MST for Mohave County, Arizona. It was in force for 16 hr.
The area
The counties it named.
The facts
- Issued
- Aug 18, 2021, 11:40 AM MST (18:40 UTC)
- Expired
- Aug 19, 2021, 3:47 AM MST
- In force
- 16 hr
- Issued by
- NWS Las Vegas, NV
- Flood severity
- None
County Mohave County, AZ
The radar
The Las Vegas radar (KESX), 102 km from the middle of the area, began a volume at 18:45 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
Las Vegas, NV (KVEF), launched 12:00Z, 6.7 hours before the alert went out and 177 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
- 2770 m above ground
- 0-6 km bulk shear
- 23 kt
- 0-1 km storm-relative helicity
- 92 m²/s²
- 0-3 km storm-relative helicity
- 83 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
809 WGUS65 KVEF 181840 FFAVEF URGENT - IMMEDIATE BROADCAST REQUESTED Flood Watch National Weather Service Las Vegas NV 1140 AM PDT Wed Aug 18 2021 ....Areas of Flash Flooding possible in Northern Mohave County this afternoon and overnight.. AZZ001-190800- /O.NEW.KVEF.FF.A.0009.210818T1840Z-210819T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Northwest Plateau- 1140 AM MST Wed Aug 18 2021 ...FLASH FLOOD WATCH IN EFFECT THROUGH LATE TONIGHT... The National Weather Service in Las Vegas has issued a * Flash Flood Watch for Northern Mohave County in Northwestern Arizona. This includes the Arizona Strip and Colorado City. * Through late tonight * Numerous thunderstorms are expected to develop through the afternoon and continue through the overnight hours. Thunderstorms training over the same areas may produce significant rainfall and result in sudden flash flooding. * Rapid onset of flash flooding is possible. Heavy rain and flooding may impact rural roads around the Mt Trumbull loop as well as highway 389. Flooding is possible in the short creek basin that could impact Colorado City. Beware of flood dangers that are more difficult to discern in the overnight hours. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Flash Flood Watch means that conditions may become favorable for flooding of washes...streams and other drainage areas in the watch area. If you are in the watch area...you should closely monitor weather forecasts and be prepared to take immediate action should heavy rain and flooding occur or a flash flood warning is issued. Listen to NOAA weather radio...commercial radio or television stations for updates on this flash flood threat or by visiting us online at weather.gov/lasvegas && $$
2 follow-up statements
659 WGUS65 KVEF 190755 FFAVEF Flood Watch National Weather Service Las Vegas NV 1255 AM PDT Thu Aug 19 2021 AZZ001-191200- /O.CON.KVEF.FF.A.0009.000000T0000Z-210819T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Northwest Plateau- Including the cities of Western Grand Canyon, Mt Trumbull, Colorado City, Tuweep, and Pipe Spring National Monument 1255 AM MST Thu Aug 19 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 5 AM MST EARLY THIS MORNING... The Flash Flood Watch continues for * A portion of northwest Arizona, including the following area, Northwest Plateau. * Until 5 AM MST early this morning. * Thunderstorms are expected to continue forming over northern Mohave County through the overnight hours. These storms are likely to train, resulting in significant rainfall over the same location for extended periods of time, likely causing sudden flash flooding. * Rapid onset of flash flooding is possible. Heavy rain and flooding may impact rural roads around the Mt. Trumbull loop as well as Highway 389. Flooding is possible in the Short Creek Basin that could impact Colorado City. Beware of flood dangers, as flood waters are harder to see over the roadway at night. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Flash Flood Watch means that conditions may become favorable for flooding of washes...streams and other drainage areas in the watch area. If you are in the watch area...you should closely monitor weather forecasts and be prepared to take immediate action should heavy rain and flooding occur or a flash flood warning is issued. Listen to NOAA Weather Radio, commercial radio, or television stations for updates on the flash flood threat. You can also look online at weather.gov/lasvegas. && $$ JV
214 WGUS65 KVEF 191047 FFAVEF Flood Watch National Weather Service Las Vegas NV 347 AM PDT Thu Aug 19 2021 AZZ001-191200- /O.CAN.KVEF.FF.A.0009.000000T0000Z-210819T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Northwest Plateau- Including the cities of Western Grand Canyon, Mt Trumbull, Colorado City, Tuweep, and Pipe Spring National Monument 347 AM MST Thu Aug 19 2021 ...FLASH FLOOD WATCH IS CANCELLED... The Flash Flood Watch for a portion of northwest Arizona, including the Northwest Plateau has been cancelled. The Flash Flood Watch is cancelled. Flooding is no longer expected to pose a threat. Please heed all road closures, if applicable. $$ JV
Nearby
Flash Flood Watches in Arizona, 2021Every flash flood watch 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.