Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 201, NWS Flagstaff, AZ

August 18, 2021Gila County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Aug 18, 2021, 9:44 AM MST for Gila County, Arizona. It was in force for 7 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 18, 2021, 9:44 AM MST (16:44 UTC)
Expired
Aug 18, 2021, 4:45 PM MST
In force
7 hr
Issued by
NWS Flagstaff, AZ
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Gila County, AZ

The radar

The Flagstaff radar (KFSX), 65 km from the middle of the area, began a volume at 16:46 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.

What was reported inside it

TimeReportWhereRemark
Aug 18, 10:30 AM MSTFLASH FLOOD2 Sse Jakes Corner, AZTHE TONTO CREEK ABOVE GUN CREEK STREAM GAGE (TNRA3) INDICATED AT 3.1 FT. RISE BETWEEN 8:45AM MST AND 10:30AM MST.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Phoenix, AZ (KPSR), launched 12:00Z, 4.7 hours before the alert went out and 86 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, Phoenix, AZ at 12:00Z on 2021-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1239 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phoenix, AZ at 12:00Z on 2021-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 52 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
1239 J/kg
Mixed-layer CIN
-34 J/kg
Mixed-layer LCL
1144 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
52 m²/s²
0-3 km storm-relative helicity
40 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

960 
WGUS55 KFGZ 181644
FFWFGZ
AZC007-181945-
/O.NEW.KFGZ.FF.W.0201.210818T1644Z-210818T1945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
944 AM MST Wed Aug 18 2021

The National Weather Service in Flagstaff has issued a

* Flash Flood Warning for...
  Gila County in east central Arizona...

* Until 1245 PM MST.

* At 942 AM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 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...
  Jakes Corner and the Bush Fire Scar.

This includes the following highways...
	State Route 188 between mile markers 267 and 276.
	State Route 87 between mile markers 230 and 235.

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. 
This includes Tonto Creek.

Avoid recently burned areas and downstream locations. This includes 
the Bush Fire Scar. Life-threatening flooding of creeks, roads and 
normally dry washes will occur. Rockslides and mudslides will likely 
occur in steep terrain.

&&

LAT...LON 3398 11141 3405 11136 3409 11128 3402 11125
      3392 11130 3397 11141

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

$$

EL
6 follow-up statements
891 
WGUS75 KFGZ 181719
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
1019 AM MST Wed Aug 18 2021

AZC007-181945-
/O.CON.KFGZ.FF.W.0201.000000T0000Z-210818T1945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-
1019 AM MST Wed Aug 18 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1245 PM MST THIS 
AFTERNOON FOR GILA COUNTY...

At 1016 AM MST, Doppler radar and the automated river gauge at Tonto 
Creek above Gun Creek indicated thunderstorms producing moderate to 
heavy rain across the warned area. Between 1 and 2 inches of rain 
have fallen with Tonto Creek rising an additional two feet for 
portions in the warned area. Flash flooding is ongoing or expected 
to begin shortly.

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

SOURCE...Radar and automated gauges.

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

Some locations that will experience flash flooding include...
  Jakes Corner and the Bush Fire Scar.

This includes the following highways...
	State Route 188 between mile markers 267 and 276.
	State Route 87 between mile markers 230 and 235.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Stay away or be swept away! The banks of creeks and washes are 
unstable and unsafe during any flooding event. This includes areas 
along Tonto Creek.

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.

Avoid recently burned areas and downstream locations. 
Life-threatening flooding of creeks, roads and normally dry washes 
will occur. Rockslides and mudslides will likely occur in steep 
terrain.

&&

LAT...LON 3398 11141 3405 11136 3409 11128 3402 11125
      3392 11130 3397 11141

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

$$

EL
523 
WGUS75 KFGZ 181801
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
1101 AM MST Wed Aug 18 2021

AZC007-181945-
/O.CON.KFGZ.FF.W.0201.000000T0000Z-210818T1945Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-
1101 AM MST Wed Aug 18 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1245 PM MST THIS 
AFTERNOON FOR GILA COUNTY NEAR JAKES CORNER...

At 1056 AM MST, Doppler radar indicated thunderstorms continuing to 
produce moderate to heavy rain across the warned area. The automated 
river gauge at Tonto Creek above Gun Creek had reported a 3 foot 
rise on Tonto Creek which has now peaked at 8.20 feet and is now 
beginning to recede. As water drains downstream, this could create 
impacts for locations along Tonto Creek near Gisela. Between 1 and 
2.5 inches of rain have fallen. Flash flooding is ongoing or 
expected to begin shortly.

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

SOURCE...Radar and automated gauges.

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

Some locations that will experience flash flooding include...
  Jakes Corner.

This includes the following highways...
	State Route 188 between mile markers 267 and 276.
	State Route 87 between mile markers 230 and 235.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Stay away or be swept away! The banks of creeks and washes are 
unstable and unsafe during any flooding event.

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.

Avoid recently burned areas and downstream locations. 
Life-threatening flooding of creeks, roads and normally dry washes 
will occur. Rockslides and mudslides will likely occur in steep 
terrain.

&&

LAT...LON 3398 11141 3405 11136 3409 11128 3402 11125
      3392 11130 3397 11141

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

$$

EL
357 
WGUS55 KFGZ 181917
FFWFGZ
AZC007-182115-
/O.EXT.KFGZ.FF.W.0201.000000T0000Z-210818T2115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
1217 PM MST Wed Aug 18 2021

The National Weather Service in Flagstaff has extended the

* Flash Flood Warning for...
  Gila County in east central Arizona...

* Until 215 PM MST.

* At 1216 PM MST, Doppler radar continues to show thunderstorms 
  producing moderate to heavy rain across the warned area. Between 1 
  and 2.5 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...
  Jakes Corner.

This includes the following highways...
	State Route 188 between mile markers 267 and 276.
	State Route 87 between mile markers 230 and 235.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Stay away or be swept away! The banks of creeks and washes are 
unstable and unsafe during any flooding event.

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.

Avoid recently burned areas and downstream locations. 
Life-threatening flooding of creeks, roads and normally dry washes 
will occur. Rockslides and mudslides will likely occur in steep 
terrain.

&&

LAT...LON 3398 11141 3405 11136 3409 11128 3402 11125
      3392 11130 3397 11141

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

$$

EL
386 
WGUS55 KFGZ 182108
FFWFGZ
AZC007-182215-
/O.EXT.KFGZ.FF.W.0201.000000T0000Z-210818T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
208 PM MST Wed Aug 18 2021

The National Weather Service in Flagstaff has extended the

* Flash Flood Warning for...
  Gila County in east central Arizona...

* Until 315 PM MST.

* At 207 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3 inches of rain 
  have fallen. Additional rainfall amounts of 0.25 to 0.75 inches 
  are possible in the warned area. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of low-water crossings, creeks,
           normally dry washes and roads.

* Some locations that will experience flash flooding include...
  Jakes Corner.

This includes the following highways...
	State Route 188 between mile markers 267 and 276.
	State Route 87 between mile markers 230 and 235.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In hilly or mountainous terrain, there are many low water crossings 
which will become dangerous in heavy rain. Do not attempt to cross 
flooded roads. Find an alternate route.

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.

Avoid recently burned areas and downstream locations. 
Life-threatening flooding of creeks, roads and normally dry washes 
will occur. Rockslides and mudslides will likely occur in steep 
terrain.

&&

LAT...LON 3398 11141 3405 11136 3409 11128 3402 11125
      3392 11130 3397 11141

FLASH FLOOD...RADAR INDICATED

$$

DB
173 
WGUS55 KFGZ 182206
FFWFGZ
AZC007-182345-
/O.EXT.KFGZ.FF.W.0201.000000T0000Z-210818T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
306 PM MST Wed Aug 18 2021

The National Weather Service in Flagstaff has extended the

* Flash Flood Warning for...
  Gila County in east central Arizona...

* Until 445 PM MST.

* At 305 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 3 and 4 inches of rain 
  have fallen. Additional rainfall amounts of 0.75 to 1.5 inches are 
  possible in the warned area. Flash flooding is ongoing or expected 
  to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of low-water crossings, creeks,
           normally dry washes and roads.

* Some locations that will experience flash flooding include...
  Jakes Corner.

This includes the following highways...
	State Route 188 between mile markers 267 and 276.
	State Route 87 between mile markers 230 and 235.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In hilly or mountainous terrain, there are many low water crossings 
which will become dangerous in heavy rain. Do not attempt to cross 
flooded roads. Find an alternate route.

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.

Avoid recently burned areas and downstream locations. 
Life-threatening flooding of creeks, roads and normally dry washes 
will occur. Rockslides and mudslides will likely occur in steep 
terrain.

&&

LAT...LON 3398 11141 3405 11136 3409 11128 3402 11125
      3392 11130 3397 11141

FLASH FLOOD...RADAR INDICATED

$$

DB
448 
WGUS75 KFGZ 182339
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
439 PM MST Wed Aug 18 2021

AZC007-182349-
/O.EXP.KFGZ.FF.W.0201.000000T0000Z-210818T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-
439 PM MST Wed Aug 18 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 445 PM MST THIS AFTERNOON FOR 
GILA 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 1100 PM MST Wednesday 
for portions of east central Arizona, north central Arizona, 
northeast Arizona and west central Arizona.

LAT...LON 3398 11141 3405 11136 3409 11128 3402 11125
      3392 11130 3397 11141

$$

DB

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 17, 5:02 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino3 hr
Aug 17, 6:23 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino2 hr
Aug 17, 8:30 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino2 hr
Aug 17, 8:42 PM MSTSevere Thunderstorm WarningFGZCoconino33 min
Aug 17, 9:07 PM MSTFlash Flood WatchFGZApache, Coconino, Gila, Navajo, Yavapai26 hr
Aug 17, 10:42 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino11 hr
Aug 18, 8:43 AM MSTSpecial Weather StatementFGZ47 min
Aug 18, 9:29 AM MSTFlash Flood Warning Considerable damage threatFGZCoconino3 hr
Aug 18, 10:37 AM MSTSpecial Weather StatementFGZ38 min
Aug 18, 10:47 AM MSTFlash Flood Warning Considerable damage threatFGZYavapai3 hr
Aug 18, 11:11 AM MSTSpecial Weather StatementFGZ34 min
Aug 18, 11:54 AM MSTSpecial Weather StatementFGZ36 min
Aug 18, 12:01 PM MSTSpecial Weather StatementFGZ44 min
Aug 18, 12:07 PM MSTFlash Flood Warning Considerable damage threatFGZApache, Navajo3 hr
Aug 18, 12:24 PM MSTFlash Flood Warning Considerable damage threatFGZYavapai3 hr
Aug 18, 12:31 PM MSTFlash Flood Warning Considerable damage threatFGZYavapai3 hr
Aug 18, 12:51 PM MSTFlash Flood Warning Considerable damage threatFGZGila, Yavapai4 hr
Aug 18, 1:05 PM MSTSevere Thunderstorm WarningFGZGila, Yavapai40 min
Aug 18, 1:09 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino3 hr
Aug 18, 1:37 PM MSTSevere Thunderstorm WarningFGZCoconino38 min
Aug 18, 1:47 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino118 min
Aug 18, 2:19 PM MSTAreal Flood AdvisoryFGZNavajo3 hr
Aug 18, 2:44 PM MSTSpecial Weather StatementFGZYavapai31 min
Aug 18, 2:52 PM MSTFlash Flood WarningFGZNavajo3 hr
Aug 18, 3:32 PM MSTFlash Flood WarningFGZCoconino, Yavapai3 hr
Aug 18, 3:45 PM MSTSpecial Weather StatementFGZ30 min
Aug 18, 4:12 PM MSTFlash Flood Warning Considerable damage threatFGZYavapai3 hr

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.