Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 42, NWS Tucson, AZ

July 18, 2021Greenlee County, Arizona

NWS Tucson, AZ issued this flash flood warning at Jul 18, 2021, 4:08 PM MST for Greenlee County, Arizona. It was in force for 112 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, 4:08 PM MST (23:08 UTC)
Expired: Jul 18, 2021, 6:00 PM MST
In force: 112 min
Issued by: NWS Tucson, AZ
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Greenlee County, AZ

The radar

The Tucson radar (KEMX), 179 km from the middle of the area, began a volume at 23:09 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

Tuscon, AZ (KTUS), launched 12:00Z, 11.1 hours before the alert went out and 178 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: 1146 J/kg
Mixed-layer CIN: -124 J/kg
Mixed-layer LCL: 1485 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: -4 m²/s²
0-3 km storm-relative helicity: 44 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

582 
WGUS55 KTWC 182308
FFWTWC
AZC011-190100-
/O.NEW.KTWC.FF.W.0042.210718T2308Z-210719T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Tucson has issued a

* Flash Flood Warning for...
  West Central Greenlee County in southeastern Arizona...

* Until 600 PM MST.

* At 408 PM MST, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain just north of the Clifton and 
  Morenci area. Between 1 and 1.5 inches of rain fell in a short 
  period of time. Flash flooding is ongoing or expected to begin 
  shortly.

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

  SOURCE...Radar and automated gauges.

  IMPACT...Flash flooding of creeks and streams in the area.

* Some locations that will experience flash flooding include...
  Areas south of Granville to Clifton and Morenci.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

Remain alert for flooding even in locations not receiving rain. 
Washes, streams, and rivers can become raging killer currents in a 
matter of minutes, even from distant rainfall.

&&

LAT...LON 3311 10941 3304 10939 3299 10932 3303 10925
      3310 10926 3315 10934 3315 10935

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

$$

CC

1 follow-up statement

065 
WGUS75 KTWC 190102
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
602 PM MST Sun Jul 18 2021

AZC011-190112-
/O.EXP.KTWC.FF.W.0042.000000T0000Z-210719T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Greenlee AZ-
602 PM MST Sun Jul 18 2021

...FLASH FLOOD WARNING HAS EXPIRED FOR WEST CENTRAL GREENLEE 
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 MST for a 
portion of Southeast Arizona.

LAT...LON 3311 10941 3304 10939 3299 10932 3303 10925
      3310 10926 3315 10934 3315 10935

$$

AH

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 17, 6:50 PM MST	Special Weather Statement	TWC	Cochise	25 min
Jul 17, 8:04 PM MST	Special Weather Statement	TWC	Graham	41 min
Jul 17, 8:28 PM MST	Special Weather Statement	TWC	Cochise	32 min
Jul 18, 6:19 AM MST	Special Weather Statement	TWC	Santa Cruz	41 min
Jul 18, 7:55 AM MST	Areal Flood Advisory	TWC	Santa Cruz	3 hr
Jul 18, 11:57 AM MST	Areal Flood Advisory	TWC	Cochise	3 hr
Jul 18, 1:00 PM MST	Areal Flood Advisory	TWC	Graham	109 min
Jul 18, 1:28 PM MST	Flash Flood Watch	TWC	Cochise, Graham, Greenlee, Pima, Pinal, Santa Cruz	11 hr
Jul 18, 2:36 PM MST	Areal Flood Advisory	TWC	Graham	3 hr
Jul 18, 3:05 PM MST	Severe Thunderstorm Warning	TWC	Graham	40 min
Jul 18, 3:36 PM MST	Areal Flood Advisory	TWC	Graham	114 min
Jul 18, 4:10 PM MST	Special Weather Statement	TWC		35 min
Jul 18, 4:16 PM MST	Areal Flood Advisory	TWC	Graham, Greenlee	119 min
Jul 18, 4:21 PM MST	Areal Flood Advisory	TWC	Graham	114 min
Jul 18, 4:36 PM MST	Flash Flood Warning Considerable damage threat	TWC	Graham, Greenlee	3 hr
Jul 18, 4:45 PM MST	Areal Flood Advisory	TWC	Cochise	2 hr
Jul 18, 4:50 PM MST	Severe Thunderstorm Warning	TWC	Cochise	40 min
Jul 18, 4:58 PM MST	Flash Flood Warning Considerable damage threat	TWC	Cochise	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.