Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 49, NWS Flagstaff, AZ

July 18, 2021Gila County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Jul 18, 2021, 5:31 PM MST for Gila County, Arizona. It was in force for 59 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 18, 2021, 5:31 PM MST (00:31 UTC)
Expired: Jul 18, 2021, 6:30 PM MST
In force: 59 min
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), 71 km from the middle of the area, began a volume at 00:35 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

Phoenix, AZ (KPSR), launched 00:00Z, 0.5 hours before the alert went out and 81 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1031 J/kg
Mixed-layer CIN: -48 J/kg
Mixed-layer LCL: 2190 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: -20 m²/s²
0-3 km storm-relative helicity: 86 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.2

Open this sounding in Storm Lab

The text

As transmitted.

983 
WGUS55 KFGZ 190031
FFWFGZ
AZC007-190130-
/O.NEW.KFGZ.FF.W.0049.210719T0031Z-210719T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Flagstaff AZ
531 PM MST Sun Jul 18 2021

The National Weather Service in Flagstaff has issued a

* Flash Flood Warning for...
  The Slate Creek basin in...
  Gila County in east central Arizona...

* Until 630 PM MST.

* At 531 PM MST, Doppler radar indicated thunderstorms producing 
  heavy rain over the Slate Creek basin. Between 1 and 2 inches of 
  rain have fallen. Additional rainfall amounts of 0.5 to 1.25 
  inches are possible in the warned area. Flash flooding is ongoing 
  or expected to begin shortly.

  HAZARD...Life-threatening flash flooding. Thunderstorms
           producing flash flooding in and around the Slate Creek
           basin.

  SOURCE...Radar.

  IMPACT...Life threatening flash flooding of areas in and around
           the Slate Creek basin.

* Some locations that will experience flash flooding include...
  mainly rural areas of Gila County

This includes the following highways...
	State Route 188 near mile marker 268.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Get to higher ground immediately! Residences near State Route 188 
along the banks of Slate Creek may be affected by high water and 
debris.

Turn Around, Don't Drown! National Forest Service Road 26 and low 
water crossings through Slate Creek will be inundated or washed out.

&&

LAT...LON 3396 11139 3397 11137 3394 11130 3393 11133

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

$$

EL

1 follow-up statement

692 
WGUS75 KFGZ 190124
FFSFGZ

Flash Flood Statement
National Weather Service Flagstaff AZ
624 PM MST Sun Jul 18 2021

AZC007-190134-
/O.EXP.KFGZ.FF.W.0049.000000T0000Z-210719T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Gila AZ-
624 PM MST Sun Jul 18 2021

...FLASH FLOOD WARNING FOR THE SLATE CREEK BASIN WILL EXPIRE AT 630 
PM MST THIS EVENING FOR GILA COUNTY...

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

LAT...LON 3396 11139 3397 11137 3394 11130 3393 11133

$$

TPS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 18, 5:43 PM MST	Severe Thunderstorm Warning	FGZ	Gila, Yavapai	24 min
Jul 18, 6:14 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	3 hr
Jul 18, 6:21 PM MST	Special Weather Statement	FGZ		24 min
Jul 19, 1:48 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	3 hr
Jul 19, 1:54 PM MST	Special Weather Statement	FGZ		51 min
Jul 19, 2:08 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	37 min
Jul 19, 2:30 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	2 hr
Jul 19, 3:07 PM MST	Special Weather Statement	FGZ		23 min
Jul 19, 3:28 PM MST	Special Weather Statement	FGZ		32 min
Jul 19, 3:37 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	3 hr
Jul 19, 4:01 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Navajo	3 hr
Jul 19, 4:27 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	2 hr

Nearby

Flash Flood Warnings in Arizona, 2021 Every 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.