Alert archive / Arizona / Flash Flood Warnings in 2019

Flash Flood Warning 60, NWS Flagstaff, AZ

September 7, 2019Yavapai County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Sep 7, 2019, 12:17 PM MST for Yavapai 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 counties it named.

The facts

Issued: Sep 7, 2019, 12:17 PM MST (19:17 UTC)
Expired: Sep 7, 2019, 3:15 PM MST
In force: 3 hr
Issued by: NWS Flagstaff, AZ
Area: Storm-based polygon
Flood severity: None

County Yavapai County, AZ

The radar

The Flagstaff radar (KFSX), 124 km from the middle of the area, began a volume at 19:19 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 12:00Z, 7.3 hours before the alert went out and 141 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: 351 J/kg
Mixed-layer CIN: -261 J/kg
Mixed-layer LCL: 2609 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 3 m²/s²
0-3 km storm-relative helicity: 83 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

What forecasters said that day

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

NWS Flagstaff, AZ wrote its last area forecast discussion before this flash flood warning went out at Sep 7, 9:02 AM MST, 3 hours 15 minutes earlier.

Area forecast discussion, Sep 7, 9:02 AM MST, 3 hours 15 minutes before

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In the hours before

Special weather statement, Sep 7, 11:20 AM MST, 57 minutes before

Special Weather Statement
National Weather Service Flagstaff AZ
1120 AM MST Sat Sep 7 2019

AZZ008-015-037-038-071845-
Yavapai County Valleys and Basins-Western Mogollon Rim-Yavapai County
Mountains-Oak Creek and Sycamore Canyons-
1120 AM MST Sat Sep 7 2019

...SIGNIFICANT WEATHER ADVISORY FOR YAVAPAI AND COCONINO COUNTIES
UNTIL 1145 AM MST...

At 1118 AM MST, Doppler radar was tracking a line of strong
thunderstorms near Stoneman Lake, or 9 miles east of Sedona, moving
northeast at 15 mph.

Pea size hail and winds in excess of 30 mph will be possible with
this storm.

This line of storms will impact travel on I-17 from Stoneman Lake
northward to mile marker 320.

LAT...LON 3474 11164 3470 11173 3486 11164 3486 11155
      3479 11160
TIME...MOT...LOC 1818Z 239DEG 12KT 3482 11163

41

Special weather statement, Sep 7, 11:52 AM MST, 25 minutes before

Special Weather Statement
National Weather Service Flagstaff AZ
1152 AM MST Sat Sep 7 2019

AZZ016-071915-
Eastern Mogollon Rim-
1152 AM MST Sat Sep 7 2019

...SIGNIFICANT WEATHER ADVISORY FOR NAVAJO COUNTY UNTIL 1215 PM
MST...

At 1151 AM MST, Doppler radar was tracking a strong thunderstorm 14
miles southwest of Aripine, or 16 miles southeast of Forest Lakes,
moving northeast at 10 mph.

Half inch hail and winds in excess of 30 mph will be possible with
this storm.

This storm will remain over mainly rural areas of Navajo County,
including the following locations... Lewis Canyon Group Campground.

LAT...LON 3411 11074 3420 11073 3444 11040 3428 11020
TIME...MOT...LOC 1851Z 220DEG 9KT 3423 11055

41

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 7, 11:20 AM MST	Special Weather Statement	FGZ		25 min
Sep 7, 11:52 AM MST	Special Weather Statement	FGZ		23 min
Sep 7, 12:33 PM MST	Flash Flood Warning	FGZ	Gila, Navajo	77 min
Sep 7, 12:53 PM MST	Special Weather Statement	FGZ		37 min
Sep 7, 1:04 PM MST	Flash Flood Warning	FGZ	Yavapai	3 hr
Sep 7, 1:16 PM MST	Special Weather Statement	FGZ		29 min
Sep 7, 1:52 PM MST	Severe Thunderstorm Warning	FGZ	Gila, Yavapai	23 min
Sep 7, 3:42 PM MST	Flash Flood Warning	FGZ	Yavapai	3 hr

Nearby

Flash Flood Warnings in Arizona, 2019 Every flash flood warning 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.