Alert archive / Arizona / Flash Flood Warnings in 2021

Flash Flood Warning 105, NWS Tucson, AZ

August 10, 2021Cochise County, Arizona

NWS Tucson, AZ issued this flash flood warning at Aug 10, 2021, 2:08 PM MST for Cochise County, Arizona. It was in force for 2 hr. 2 reports 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 10, 2021, 2:08 PM MST (21:08 UTC)
Expired: Aug 10, 2021, 4:30 PM MST
In force: 2 hr
Issued by: NWS Tucson, AZ
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Cochise County, AZ

The radar

The Tucson radar (KEMX), 70 km from the middle of the area, began a volume at 21:12 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

Time	Report	Where	Remark
Aug 10, 2:10 PM MST	FLASH FLOOD	11 Se Sierra Vista, AZ	WATER COVERED MOSON RD. CURB TO CURB. AT INTERSECTION WITH HEREFORD RD. COUNTY HAS CLOSED MOSON RD. DUE TO FLOODING.
Aug 10, 3:18 PM MST	HEAVY RAIN 3.1	13 Sse Sierra Vista, AZ

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

The nearest sounding before it

Tuscon, AZ (KTUS), launched 12:00Z, 9.1 hours before the alert went out and 110 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: 1176 J/kg
Mixed-layer CIN: -50 J/kg
Mixed-layer LCL: 1330 m above ground
0-6 km bulk shear: 1 kt
0-1 km storm-relative helicity: 18 m²/s²
0-3 km storm-relative helicity: 16 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

071 
WGUS55 KTWC 102108
FFWTWC
AZC003-102330-
/O.NEW.KTWC.FF.W.0105.210810T2108Z-210810T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Tucson AZ
208 PM MST Tue Aug 10 2021

The National Weather Service in Tucson has issued a

* Flash Flood Warning for...
  Southwestern Cochise County in southeastern Arizona...

* Until 430 PM MST.

* At 208 PM MST, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  1 and 2 inches of rain have fallen. A rain gage near Hwy 92 and S 
  Stone Ridge Rd received 1.7 inches. 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 creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  Sierra Vista, Hereford and Coronado National Memorial.

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.

&&

LAT...LON 3133 11025 3142 11027 3147 11023 3146 11014
      3134 11016 3133 11019 3133 11022

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

$$

AH

2 follow-up statements

056 
WGUS75 KTWC 102159
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
259 PM MST Tue Aug 10 2021

AZC003-102330-
/O.CON.KTWC.FF.W.0105.000000T0000Z-210810T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Cochise AZ-
259 PM MST Tue Aug 10 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 430 PM MST THIS 
AFTERNOON FOR SOUTHWESTERN COCHISE COUNTY...

At 259 PM MST, Doppler radar and automated rain gauges indicated 
thunderstorms producing heavy rain across the warned area. Between 1 
and 3 inches of rain have fallen. Two rain gages near Ash Canyon Rd 
and Hwy 92 have recorded a little over 3 inches of rain in the last 
hour and a half. 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 creeks and streams,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Sierra Vista, Hereford and Coronado National Memorial.

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.

&&

LAT...LON 3133 11025 3142 11027 3147 11023 3146 11014
      3134 11016 3133 11019 3133 11022

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

$$

AH

088 
WGUS75 KTWC 102321 RRA
FFSTWC

Flash Flood Statement
National Weather Service Tucson AZ
421 PM MST Tue Aug 10 2021

AZC003-102331-
/O.EXP.KTWC.FF.W.0105.000000T0000Z-210810T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Cochise AZ-
421 PM MST Tue Aug 10 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 430 PM MST THIS AFTERNOON FOR 
SOUTHWESTERN COCHISE COUNTY...

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

LAT...LON 3133 11025 3142 11027 3147 11023 3146 11014
      3134 11016 3133 11019 3133 11022

$$

AH

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 10, 4:04 AM MST	Areal Flood Advisory	TWC	Pima, Pinal	3 hr
Aug 10, 4:44 AM MST	Special Weather Statement	TWC		46 min
Aug 10, 5:12 AM MST	Flash Flood Warning	TWC	Pima, Pinal	3 hr
Aug 10, 5:39 AM MST	Areal Flood Advisory	TWC	Pima, Pinal	111 min
Aug 10, 6:26 AM MST	Flash Flood Warning Considerable damage threat	TWC	Pima, Pinal	5 hr
Aug 10, 6:49 AM MST	Areal Flood Advisory	TWC	Cochise, Graham	116 min
Aug 10, 6:55 AM MST	Areal Flood Advisory	TWC	Cochise, Pima, Pinal	4 hr
Aug 10, 8:27 AM MST	Areal Flood Advisory	TWC	Graham, Greenlee	3 hr
Aug 10, 8:32 AM MST	Flash Flood Warning Considerable damage threat	TWC	Greenlee	3 hr
Aug 10, 9:11 AM MST	Areal Flood Advisory	TWC	Pima, Santa Cruz	3 hr
Aug 10, 10:51 AM MST	Areal Flood Warning	TWC	Pima, Pinal	18 hr
Aug 10, 11:00 AM MST	Areal Flood Advisory	TWC	Cochise, Pima, Pinal	2 hr
Aug 10, 11:09 AM MST	Areal Flood Advisory	TWC	Cochise, Graham	111 min
Aug 10, 11:41 AM MST	Flash Flood Warning Considerable damage threat	TWC	Cochise	3 hr
Aug 10, 12:52 PM MST	Special Weather Statement	TWC	Cochise	38 min
Aug 10, 12:55 PM MST	Severe Thunderstorm Warning	TWC	Cochise	50 min
Aug 10, 1:38 PM MST	Special Weather Statement	TWC	Cochise	52 min
Aug 10, 1:43 PM MST	Areal Flood Advisory	TWC	Cochise	3 hr
Aug 10, 1:46 PM MST	Areal Flood Advisory	TWC	Cochise	119 min
Aug 10, 1:58 PM MST	Flash Flood Warning Considerable damage threat	TWC	Cochise	3 hr
Aug 10, 2:00 PM MST	Special Weather Statement	TWC		45 min
Aug 10, 2:39 PM MST	Flash Flood Warning Considerable damage threat	TWC	Cochise	3 hr
Aug 10, 3:41 PM MST	Special Weather Statement	TWC	Santa Cruz	34 min
Aug 10, 4:38 PM MST	Special Weather Statement	TWC	Santa Cruz	52 min
Aug 10, 4:39 PM MST	Special Weather Statement	TWC	Pima	36 min

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