Alert archive / Arizona / Flash Flood Warnings in 2019

Flash Flood Warning 38, NWS Flagstaff, AZ

August 3, 2019Yavapai County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Aug 3, 2019, 1:28 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
Aug 3, 2019, 1:28 PM MST (20:28 UTC)
Expired
Aug 3, 2019, 4:30 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 20:31 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, 8.5 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-pSkew-T log-p diagram, Phoenix, AZ at 12:00Z on 2019-08-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 206 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phoenix, AZ at 12:00Z on 2019-08-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 38 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
206 J/kg
Mixed-layer CIN
-376 J/kg
Mixed-layer LCL
2943 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
38 m²/s²
0-3 km storm-relative helicity
33 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 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 Aug 3, 9:46 AM MST, 3 hours 42 minutes earlier.

Area forecast discussion, Aug 3, 9:46 AM MST, 3 hours 42 minutes before
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In the hours before

Special weather statement, Aug 3, 12:11 PM MST, 1 hour 17 minutes before
Special Weather Statement
National Weather Service Flagstaff AZ
111 PM MDT Sat Aug 3 2019

AZZ011-032000-
Chuska Mountains and Defiance Plateau-
111 PM MDT Sat Aug 3 2019

...SIGNIFICANT WEATHER ADVISORY FOR APACHE COUNTY UNTIL 200 PM MDT...

At 109 PM MDT, Doppler radar was tracking a cluster of strong
thunderstorms 10 miles southeast of Kinlichee Chapter House, or 32
miles west of Gallup, moving northeast at 15 mph.

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

Locations impacted include...
Fort Defiance, Window Rock, St. Michaels and Sawmill.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3548 10907 3560 10941 3595 10925 3585 10904
      3556 10905
TIME...MOT...LOC 1909Z 211DEG 12KT 3568 10927

JDS
Special weather statement, Aug 3, 1:14 PM MST, 14 minutes before
Special Weather Statement
National Weather Service Flagstaff AZ
114 PM MST Sat Aug 3 2019

AZZ013-014-016-017-032100-
Little Colorado River Valley in Navajo County-Little Colorado River
Valley in Apache County-White Mountains-Eastern Mogollon Rim-
114 PM MST Sat Aug 3 2019

...SIGNIFICANT WEATHER ADVISORY FOR APACHE AND NAVAJO COUNTIES UNTIL
200 PM MST...

At 114 PM MST, Doppler radar was tracking a strong thunderstorm 8
miles east of Show Low, moving north at 15 mph.

Penny size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
White Mountain Lake.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3424 10981 3421 10999 3443 11005 3444 10988
TIME...MOT...LOC 2014Z 164DEG 11KT 3431 10992

JDS

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 2, 5:25 PM MSTFlash Flood WarningFGZYavapai3 hr
Aug 2, 6:07 PM MSTSpecial Weather StatementFGZ38 min
Aug 2, 6:12 PM MSTFlash Flood WarningFGZYavapai3 hr
Aug 2, 6:27 PM MSTSevere Thunderstorm WarningFGZYavapai37 min
Aug 2, 7:02 PM MSTSpecial Weather StatementFGZYavapai28 min
Aug 2, 7:09 PM MSTFlash Flood WarningFGZCoconino3 hr
Aug 3, 12:11 PM MSTSpecial Weather StatementFGZApache49 min
Aug 3, 1:14 PM MSTSpecial Weather StatementFGZ46 min
Aug 3, 1:55 PM MSTSpecial Weather StatementFGZ50 min
Aug 3, 2:14 PM MSTSpecial Weather StatementFGZ46 min
Aug 3, 2:30 PM MSTSevere Thunderstorm WarningFGZYavapai45 min
Aug 3, 3:25 PM MSTSevere Thunderstorm WarningFGZYavapai35 min
Aug 3, 4:19 PM MSTFlash Flood WarningFGZGila3 hr
Aug 3, 4:29 PM MSTFlash Flood WarningFGZGila3 hr

Nearby

Flash Flood Warnings in Arizona, 2019Every 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.