Alert archive / Arizona / Flash Flood Watches in 2019

Flash Flood Watch 4, NWS Tucson, AZ

September 23, 20196 counties in Arizona

NWS Tucson, AZ issued this flash flood watch at Sep 23, 2019, 2:57 AM MST for 6 counties in Arizona. It took effect at Sep 23, 2019, 5:00 AM MST. It was in force for 39 hr.

The area

The counties it named.

The facts

Issued: Sep 23, 2019, 2:57 AM MST (09:57 UTC)
In effect from: Sep 23, 2019, 5:00 AM MST
Expired: Sep 24, 2019, 8:00 PM MST
In force: 39 hr
Issued by: NWS Tucson, AZ
Flood severity: None

Counties Cochise County, AZ, Graham County, AZ, Greenlee County, AZ, Pima County, AZ, Pinal County, AZ, Santa Cruz County, AZ

The radar

The Tucson radar (KEMX), 61 km from the middle of the area, began a volume at 09:58 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, 10.0 hours before the alert went out and 179 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 3610 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 11 m²/s²
0-3 km storm-relative helicity: 61 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 flash flood watch 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 flash flood watch went out at Sep 22, 2:52 PM MST, 12 hours 5 minutes earlier.

Area forecast discussion, Sep 22, 2:52 PM MST, 12 hours 5 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 23, 2:32 PM MST	Dust Storm Warning	TWC	Pima, Pinal	88 min
Sep 23, 3:51 PM MST	Dust Storm Warning	TWC	Pima, Pinal	54 min

Nearby

Flash Flood Watches in Arizona, 2019 Every flash flood watch in 2019

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.