Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 65, NWS Flagstaff, AZ

July 21, 2021Yavapai County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Jul 21, 2021, 12:13 PM MST for Yavapai County, Arizona. It was in force for 56 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
Jul 21, 2021, 12:13 PM MST (19:13 UTC)
Expired
Jul 21, 2021, 1:09 PM MST
In force
56 min
Issued by
NWS Flagstaff, AZ
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Yavapai County, AZ

The radar

The Flagstaff radar (KFSX), 94 km from the middle of the area, began a volume at 19:15 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

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 7.2 hours before the alert went out and 64 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, Flgstf/Belemont, AZ at 12:00Z on 2021-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 77 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 12:00Z on 2021-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 20 square meters per square second.1939Sfc1 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
77 J/kg
Mixed-layer CIN
-129 J/kg
Mixed-layer LCL
1785 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
20 m²/s²
0-3 km storm-relative helicity
-11 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

810 
WGUS55 KFGZ 211913
FFWFGZ
AZC025-212215-
/O.NEW.KFGZ.FF.W.0065.210721T1913Z-210721T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
1213 PM MST Wed Jul 21 2021

The National Weather Service in Flagstaff has issued a

* Flash Flood Warning for...
  Yavapai County in west central Arizona...

* Until 315 PM MST.

* At 1213 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 1.5 inches of 
  rain have fallen. Additional rainfall amounts of 0.5 to 1 inch are 
  possible in the warned area. 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 low-water
           crossings, creeks, normally dry washes and roads.

* Some locations that will experience flash flooding include...
  Potato Patch Campground and Playground Group Campground.

This includes the following highways...
	State Route 89A between mile markers 330 and 343.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Remain alert for flooding even in locations not receiving rain. 
Normally dry washes, slot canyons and creeks can become raging 
killer currents in a matter of minutes, even from distant rainfall.

&&

LAT...LON 3480 11227 3483 11216 3471 11209 3465 11222

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

EL
2 follow-up statements
834 
WGUS75 KFGZ 211939
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
1239 PM MST Wed Jul 21 2021

AZC025-212215-
/O.CON.KFGZ.FF.W.0065.000000T0000Z-210721T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Yavapai AZ-
1239 PM MST Wed Jul 21 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 315 PM MST THIS 
AFTERNOON FOR YAVAPAI COUNTY...

At 1237 PM MST, Doppler radar indicated the rainfall intensity has 
decreased across the warned area, however light to moderate rain is 
still taking place with flooding likely as water drains. Between 1 
and 2 inches of rain have fallen. Additional rainfall amounts of 
0.25 to 0.5 inches are possible in the warned area.

HAZARD...Life-threatening flash flooding. Thunderstorms producing
         flash flooding.

SOURCE...Radar.

IMPACT...Life-threatening flash flooding of low-water crossings,
         creeks, normally dry washes and roads.

Some locations that will experience flash flooding include...
  Potato Patch Campground and Playground Group Campground.

This includes the following highways...
	State Route 89A between mile markers 331 and 344.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Remain alert for flooding even in locations not receiving rain. 
Normally dry washes, slot canyons and creeks can become raging 
killer currents in a matter of minutes, even from distant rainfall.

&&

LAT...LON 3480 11227 3483 11216 3471 11209 3465 11222

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

EL
383 
WGUS75 KFGZ 212009
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
109 PM MST Wed Jul 21 2021

AZC025-212019-
/O.CAN.KFGZ.FF.W.0065.000000T0000Z-210721T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Yavapai AZ-
109 PM MST Wed Jul 21 2021

...FLASH FLOOD WARNING IS CANCELLED NEAR PONDEROSA PARK IN YAVAPAI 
COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

LAT...LON 3480 11227 3483 11216 3471 11209 3465 11222

$$

EL

The office that day

Everything else NWS Flagstaff, AZ issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 20, 6:16 PM MSTSpecial Weather StatementFGZ29 min
Jul 20, 7:32 PM MSTSevere Thunderstorm WarningFGZNavajo28 min
Jul 20, 7:55 PM MSTFlash Flood Warning Considerable damage threatFGZNavajo2 hr
Jul 20, 8:33 PM MSTFlash Flood Warning Considerable damage threatFGZNavajo117 min
Jul 21, 12:17 AM MSTFlash Flood Warning Considerable damage threatFGZGila118 min
Jul 21, 2:38 AM MSTFlash Flood WatchFGZApache, Coconino, Gila, Navajo, Yavapai5 days
Jul 21, 10:19 AM MSTSpecial Weather StatementFGZYavapai26 min
Jul 21, 10:48 AM MSTFlash Flood Warning Considerable damage threatFGZYavapai2 hr
Jul 21, 12:03 PM MSTSpecial Weather StatementFGZYavapai42 min
Jul 21, 12:20 PM MSTFlash Flood Warning Considerable damage threatFGZYavapai114 min
Jul 21, 12:35 PM MSTSpecial Weather StatementFGZ40 min
Jul 21, 12:47 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino118 min
Jul 21, 12:54 PM MSTSpecial Weather StatementFGZ36 min
Jul 21, 1:06 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino92 min
Jul 21, 1:24 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino110 min
Jul 21, 1:27 PM MSTFlash Flood Warning Considerable damage threatFGZYavapai74 min
Jul 21, 1:57 PM MSTSpecial Weather StatementFGZYavapai48 min
Jul 21, 2:01 PM MSTAreal Flood AdvisoryFGZYavapai119 min
Jul 21, 2:05 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino2 hr
Jul 21, 2:22 PM MSTAreal Flood AdvisoryFGZCoconino3 hr
Jul 21, 2:30 PM MSTSpecial Weather StatementFGZ45 min
Jul 21, 2:36 PM MSTFlash Flood Warning Considerable damage threatFGZYavapai54 min
Jul 21, 2:53 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino82 min
Jul 21, 2:57 PM MSTFlash Flood Warning Considerable damage threatFGZYavapai60 min
Jul 21, 2:59 PM MSTFlash Flood Warning Considerable damage threatFGZYavapai60 min
Jul 21, 3:21 PM MSTSevere Thunderstorm WarningFGZCoconino26 min
Jul 21, 3:34 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino98 min
Jul 21, 3:49 PM MSTFlash Flood Warning Considerable damage threatFGZYavapai3 hr
Jul 21, 4:35 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino115 min

Nearby

Flash Flood Warnings in Arizona, 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.