Alert archive / Arizona / Flash Flood Warnings in 2019

Flash Flood Warning 56, NWS Flagstaff, AZ

August 29, 2019Coconino County, Gila County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Aug 29, 2019, 3:18 PM MST for Coconino County, Gila 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 29, 2019, 3:18 PM MST (22:18 UTC)
Expired
Aug 29, 2019, 6:15 PM MST
In force
3 hr
Issued by
NWS Flagstaff, AZ
Area
Storm-based polygon
Flood severity
None

Counties Coconino County, AZ, Gila County, AZ

The radar

The Flagstaff radar (KFSX), 29 km from the middle of the area, began a volume at 22:18 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

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 10.3 hours before the alert went out and 65 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, Flgstf/Belemont, AZ at 12:00Z on 2019-08-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 512 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 12:00Z on 2019-08-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 64 square meters per square second.193958Sfc1 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
512 J/kg
Mixed-layer CIN
-126 J/kg
Mixed-layer LCL
1398 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
64 m²/s²
0-3 km storm-relative helicity
32 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 29, 2:34 PM MST, 44 minutes earlier.

Area forecast discussion, Aug 29, 2:34 PM MST, 44 minutes before
Area Forecast Discussion
National Weather Service Flagstaff AZ
234 PM MST Thu Aug 29 2019

.SYNOPSIS...look for decreasing afternoon storm coverage and
warmer afternoon temperatures across northern Arizona through
Saturday. Storm chances to increase from east to west starting
Sunday with typical late monsoon season storm chances through
Wednesday.

&&

.DISCUSSION...
Scattered thunderstorm continue this afternoon along the Mogollon
rim from Flagstaff through the White Mountains. A well defined
outflow boundary is moving southeastward from Munds Park, and
this feature may kick off some storms in the Oak creek and Sedona
areas later this afternoon. Elsewhere isolated storms are
occurring over areas above 6500, with mostly sunny skies noted
across northwest AZ.

Friday and Saturday...Progs continue to show the high pressure
center to move from southern California to near the 4 corners
during this period. This will bring a downward trend in storm
coverage both days, with afternoon storm chances limited to along
and south of the Mogollon Rim. Light north to northeast steering
flow keeps the potential for storms to drop southward from the rim
into Gila county Friday afternoon. Max temps will be on a warming
trend, with values around 10 degrees above average on Saturday.
Fair weather is expected overnight.

Long Term...Sunday through Wednesday...The chances for showers
and thunderstorms will begin to increase again starting Sunday
afternoon. This is the result of another shift in the placement of
the high pressure. Model guidance is in good consensus that the
center of the high pressure will once again be back over the Four
Corners region by Saturday night and introduce a general easterly
flow pattern to Arizona. The east to southeasterly flow will help
to transport additional moisture back into the County Warning Area
for expanded convection on Sunday afternoon and beyond.

&&

.AVIATION...For the 00Z package...Scattered showers and storms
to persist along and south of the Mogollon rim through 03z then
diminish with fair weather overnight. After 18z Friday, widely
scattered storms are forecast along the Mogollon rim from
Flagstaff to the White Mountains with fair weather elsewhere.
Aviation discussion not updated for TAF amendments.

&&

.FIRE WEATHER...For Friday and Saturday, warmer and much drier
conditons to return to northern Arizona. Max temps should be from
5 to 10 degrees above normal. Widely scattered afternoon storms
are expected along the Mogollon Rim from Flagstaff to the White
Mountains Friday, with less coverage forecast Saturday.

Sunday through Tuesday...East to southeast flow aloft should bring
a return of monsoon moisture to eastern Arizona Sunday. Thus,
storm coverage is expected to increase again from east to west
through Tuesday.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...NONE.

&&

SHORT TERM PUBLIC...DL
LONG TERM PUBLIC...NL
AVIATION...DL
FIRE WEATHER...DL

For Northern Arizona weather information visit
weather.gov/flagstaff

In the hours before

Special weather statement, Aug 29, 12:37 PM MST, 2 hours 41 minutes before
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Local storm report, Aug 29, 1:18 PM MST, 2 hours before
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Special weather statement, Aug 29, 1:22 PM MST, 1 hour 56 minutes before
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  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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Special weather statement, Aug 29, 1:44 PM MST, 1 hour 34 minutes before
Special Weather Statement
National Weather Service Flagstaff AZ
144 PM MST Thu Aug 29 2019

AZZ016-292130-
Eastern Mogollon Rim-
144 PM MST Thu Aug 29 2019

...SIGNIFICANT WEATHER ADVISORY FOR EXTREME SOUTHEAST COCONINO
COUNTY UNTIL 230 PM MST...

At 142 PM MST, Doppler radar was tracking a strong thunderstorm 13
miles north of Christopher Creek, or 13 miles northwest of Forest
Lakes, moving east at 10 mph.

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

Locations impacted include...
Chevelon Canyon Lake Campground and Chevelon Canyon Dam.

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.

&&

LAT...LON 3442 11104 3460 11098 3456 11077 3436 11077
TIME...MOT...LOC 2042Z 283DEG 10KT 3450 11093

JJ
Special weather statement, Aug 29, 1:49 PM MST, 1 hour 29 minutes before
Special Weather Statement
National Weather Service Flagstaff AZ
149 PM MST Thu Aug 29 2019

AZZ015-292115-
Western Mogollon Rim-
149 PM MST Thu Aug 29 2019

...SIGNIFICANT WEATHER ADVISORY FOR NEAR MOUNTAINAIRE IN COCONINO
COUNTY UNTIL 215 PM MST...

At 147 PM MST, Doppler radar was tracking a strong thunderstorm over
Mountainaire, or 7 miles south of Flagstaff, moving southeast at 10
mph.

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

Locations impacted include...
Mountainaire and Upper Lake Mary.

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.

&&

LAT...LON 3506 11171 3512 11168 3508 11149 3496 11158
TIME...MOT...LOC 2047Z 301DEG 9KT 3508 11164

JJ
Special weather statement, Aug 29, 2:16 PM MST, 1 hour 2 minutes before
Special Weather Statement
National Weather Service Flagstaff AZ
216 PM MST Thu Aug 29 2019

AZZ015-292145-
Western Mogollon Rim-
216 PM MST Thu Aug 29 2019

...SIGNIFICANT WEATHER ADVISORY FOR MOUNTAINAIRE IN COCONINO COUNTY
UNTIL 245 PM MST...

At 215 PM MST, Doppler radar was tracking a strong thunderstorm over
Mountainaire, or 9 miles south of Flagstaff, moving east at 10 mph.

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

Locations impacted include...
Mountainaire, Kachina Village and Upper Lake Mary.

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.

&&

LAT...LON 3504 11171 3510 11169 3509 11152 3497 11159
TIME...MOT...LOC 2115Z 286DEG 7KT 3506 11165

JJ

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 28, 6:47 PM MSTFlash Flood WarningFGZCoconino, Navajo88 min
Aug 28, 8:35 PM MSTFlash Flood WarningFGZGila, Yavapai3 hr
Aug 29, 12:37 PM MSTSpecial Weather StatementFGZ23 min
Aug 29, 1:18 PM MSTAreal Flood AdvisoryFGZCoconino117 min
Aug 29, 1:22 PM MSTSpecial Weather StatementFGZ23 min
Aug 29, 1:44 PM MSTSpecial Weather StatementFGZ46 min
Aug 29, 1:49 PM MSTSpecial Weather StatementFGZ26 min
Aug 29, 2:16 PM MSTSpecial Weather StatementFGZ29 min
Aug 29, 2:31 PM MSTFlash Flood WarningFGZCoconino3 hr
Aug 29, 2:40 PM MSTAreal Flood AdvisoryFGZCoconino2 hr
Aug 29, 3:32 PM MSTSpecial Weather StatementFGZ43 min
Aug 29, 3:36 PM MSTSpecial Weather StatementFGZYavapai39 min
Aug 29, 3:58 PM MSTAreal Flood AdvisoryFGZCoconino3 hr
Aug 29, 4:25 PM MSTSpecial Weather StatementFGZ50 min
Aug 29, 4:33 PM MSTSevere Thunderstorm WarningFGZGila, Yavapai27 min
Aug 29, 4:54 PM MSTSevere Thunderstorm WarningFGZGila, Yavapai36 min

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.