Alert archive / Arizona / Areal Flood Advisories in 2021

Areal Flood Advisory 49, NWS Tucson, AZ

July 18, 2021Cochise County, Arizona

NWS Tucson, AZ issued this areal flood advisory at Jul 18, 2021, 11:57 AM MST for Cochise County, Arizona. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued: Jul 18, 2021, 11:57 AM MST (18:57 UTC)
Expired: Jul 18, 2021, 2:47 PM MST
In force: 3 hr
Issued by: NWS Tucson, AZ
Area: Storm-based polygon

County Cochise County, AZ

The radar

The Tucson radar (KEMX), 83 km from the middle of the area, began a volume at 18:59 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, 7.0 hours before the alert went out and 113 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

What forecasters said that day

The local office's own words before this areal flood advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Tucson, AZ wrote its last area forecast discussion before this areal flood advisory went out at Jul 18, 10:01 AM MST, 1 hour 56 minutes earlier.

Area forecast discussion, Jul 18, 10:01 AM MST, 1 hour 56 minutes before

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In the hours before

Special weather statement, Jul 18, 6:19 AM MST, 5 hours 38 minutes before

Special Weather Statement
National Weather Service Tucson AZ
619 AM MST Sun Jul 18 2021

AZZ503-507-513-181400-
Upper San Pedro River Valley including Sierra
Vista/Benson-Dragoon/Mule/Huachuca and Santa Rita Mountains including
Bisbee/Canelo Hills/Madera Canyon-Upper Santa Cruz River and Altar
Valleys including Nogales-
619 AM MST Sun Jul 18 2021

...SIGNIFICANT WEATHER ADVISORY FOR SANTA CRUZ COUNTY UNTIL 700 AM
MST...

At 617 AM MST, Doppler radar was tracking a cluster of strong
thunderstorm near Elgin and Nogales, moving west at 5 mph.

Locally heavy rainfall and winds in excess of 40 mph will be
possible with these storms.

Locations impacted include...
Nogales, Tubac, Rio Rico, Patagonia, Sonoita, Elgin, Patagonia Lake
State Park, Nogales International Airport, Tumacacori, Amado, Kino
Springs, Pena Blanca Lake, Canelo and Lochiel.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Heavy rainfall is also occurring with this storm, and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3138 11122 3172 11106 3167 11048 3133 11052
      3133 11108
TIME...MOT...LOC 1317Z 067DEG 6KT 3156 11058

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, 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, 4:08 PM MST	Flash Flood Warning Considerable damage threat	TWC	Greenlee	112 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

Areal Flood Advisories in Arizona, 2021 Every areal flood advisory 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.