Alert archive / Arizona / Flash Flood Warnings in 2021
Flash Flood Warning 170, NWS Tucson, AZ
NWS Tucson, AZ issued this flash flood warning at Sep 25, 2021, 6:46 PM MST for Pima County, Pinal County, Arizona. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Sep 25, 2021, 6:46 PM MST (01:46 UTC)
- Expired
- Sep 25, 2021, 9:16 PM MST
- In force
- 3 hr
- Issued by
- NWS Tucson, AZ
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Flood severity
- None
Counties Pima County, AZ, Pinal County, AZ
The radar
The Tucson radar (KEMX), 64 km from the middle of the area, began a volume at 01:46 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.
The nearest sounding before it
Tuscon, AZ (KTUS), launched 00:00Z, 1.8 hours before the alert went out and 37 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.
- Mixed-layer CAPE
- 306 J/kg
- Mixed-layer CIN
- -34 J/kg
- Mixed-layer LCL
- 2537 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- -10 m²/s²
- 0-3 km storm-relative helicity
- 34 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted.
915
WGUS55 KTWC 260146
FFWTWC
AZC019-021-260430-
/O.NEW.KTWC.FF.W.0170.210926T0146Z-210926T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Tucson AZ
646 PM MST Sat Sep 25 2021
The National Weather Service in Tucson has issued a
* Flash Flood Warning for...
Northeastern Pima County in southeastern Arizona...
Southeastern Pinal County in southeastern Arizona...
* Until 930 PM MST.
* At 646 PM 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 1 to 2 inches are
possible in the warned area. Flash flooding is ongoing or expected
to begin shortly.
Excessive rainfall over the burn scar will result in debris flow
moving through the Big Horn Burn Scar. The debris flow can consist
of rock, mud, vegetation and other loose materials.
HAZARD...Life threatening flash flooding. Thunderstorms
producing flash flooding.
SOURCE...Radar.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets and underpasses.
* Some locations that will experience flash flooding include...
Catalina, Oro Valley, Oracle, Saddlebrooke, San Manuel, Mount
Lemmon/Summerhaven, Catalina State Park, Catalina Foothills, Campo
Bonito, Redington and Biosphere 2.
This includes the following Flash Flood Prone Locations...
River Rd at San Pedro River.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Move away from recently burned areas. Life-threatening flooding of
creeks, roads and normally dry washes is likely. The heavy rains
will likely trigger rockslides, mudslides and debris flows in steep
terrain, especially in and around these areas.
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Move to higher ground now. Act quickly to protect your life.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
&&
LAT...LON 3259 11086 3260 11066 3265 11046 3249 11046
3240 11046 3233 11046 3233 11064 3233 11082
3235 11094 3240 11094 3245 11092 3249 11088
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
MJS1 follow-up statement
823
WGUS75 KTWC 260416
FFSTWC
Flash Flood Statement
National Weather Service Tucson AZ
916 PM MST Sat Sep 25 2021
AZC019-021-260426-
/O.CAN.KTWC.FF.W.0170.000000T0000Z-210926T0430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Pima AZ-Pinal AZ-
916 PM MST Sat Sep 25 2021
...FLASH FLOOD WARNING IS CANCELLED FOR NORTHEASTERN PIMA AND
SOUTHEASTERN PINAL COUNTIES...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.
LAT...LON 3259 11086 3260 11066 3265 11046 3249 11046
3240 11046 3233 11046 3233 11064 3233 11082
3235 11094 3240 11094 3245 11092 3249 11088
$$
MJSThe office that day
Everything else NWS Tucson, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 25, 5:03 PM MST | Areal Flood Advisory | TWC | Cochise | 3 hr |
| Sep 25, 6:27 PM MST | Areal Flood Advisory | TWC | Cochise, Graham, Pima, Pinal | 3 hr |
| Sep 25, 7:17 PM MST | Areal Flood Advisory | TWC | Pima | 3 hr |
| Sep 26, 11:51 AM MST | Special Weather Statement | TWC | Cochise | 39 min |
| Sep 26, 11:57 AM MST | Severe Thunderstorm Warning | TWC | Cochise | 28 min |
| Sep 26, 12:20 PM MST | Special Weather Statement | TWC | 40 min | |
| Sep 26, 12:44 PM MST | Special Weather Statement | TWC | Santa Cruz | 46 min |
| Sep 26, 12:58 PM MST | Special Weather Statement | TWC | Cochise | 47 min |
| Sep 26, 1:21 PM MST | Special Weather Statement | TWC | 39 min | |
| Sep 26, 1:40 PM MST | Severe Thunderstorm Warning | TWC | Pima, Santa Cruz | 50 min |
| Sep 26, 2:18 PM MST | Special Weather Statement | TWC | Santa Cruz | 42 min |
| Sep 26, 2:33 PM MST | Areal Flood Advisory | TWC | Pima, Santa Cruz | 104 min |
| Sep 26, 2:56 PM MST | Severe Thunderstorm Warning | TWC | Pima | 49 min |
| Sep 26, 3:43 PM MST | Special Weather Statement | TWC | Santa Cruz | 47 min |
| Sep 26, 4:24 PM MST | Special Weather Statement | TWC | Pima | 51 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.