Alert archive / Arizona / Flash Flood Warnings in 2024

Flash Flood Warning 33, NWS Flagstaff, AZ

July 17, 2024Yavapai County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Jul 17, 2024, 4:51 PM MST for Yavapai County, Arizona. It was in force for 2 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
Jul 17, 2024, 4:51 PM MST (23:51 UTC)
Expired
Jul 17, 2024, 7:05 PM MST
In force
2 hr
Issued by
NWS Flagstaff, AZ
Area
Storm-based polygon
Damage threat
Considerable
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 23:53 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, 11.9 hours before the alert went out and 98 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 2024-07-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 151 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 2024-07-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -1 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
151 J/kg
Mixed-layer CIN
-114 J/kg
Mixed-layer LCL
2354 m above ground
0-6 km bulk shear
3 kt
0-1 km storm-relative helicity
-1 m²/s²
0-3 km storm-relative helicity
24 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 Jul 17, 4:07 PM MST, 44 minutes earlier.

Area forecast discussion, Jul 17, 4:07 PM MST, 44 minutes before
Area Forecast Discussion
National Weather Service Flagstaff AZ
407 PM MST Wed Jul 17 2024

.SYNOPSIS...Scattered showers and thunderstorms are expected each
day through the next week as a moderate monsoon pattern continues
across the region. Temperatures will remain above average through
the weekend with typical afternoon winds.

&&

.DISCUSSION...Storms have developed again today over the higher
terrain, with somewhat greater coverage than yesterday. With the
weak steering winds, the slow-moving storms have the potential for
heavy rain and some local flash flooding this afternoon and
evening. The greatest instability (CAPE) will be along and just
south of the Mogollon Rim (again), and some storms will likely
build toward the greater instability in Gila and Yavapai Counties
later this afternoon against the generally southerly steering
flow.

Over the next couple days the strong ridge over the Great Basin
will slowly move westward, bringing the ambient moisture with it.
With this, we'll see little change in the overall convective
potential across northern AZ as the axis of the ridge settles in
to our west - but the distribution of the precipitation will
evolve as the steering flow slowly changes. While the details can
not be resolved at this time, isolated to scattered thunderstorms
should be expected each day through the forecast period, with a
continued threat of heavier precipitation from the Mogollon Rim
to the south with this pattern.

Under the strong ridge, very warm (even hot) temperatures are
forecast to continue into the weekend with maximum temperatures
running 5-10 degrees above normal for mid-July through Saturday.
We are just below our excessive heat criteria, but the accumulated
heat stress will continue to impact those in the valley areas.

&&

.AVIATION...Thursday 18/00Z through Friday 19/00Z...VFR conditions
mainly persist through the TAF period, minus brief MVFR conditions
in stronger storms. SHRA/TSRA activity will diminish through 06Z,
with only a few stray showers likely afterwards. Expect another
round of showers/thunderstorms after 18Z across much of northern
Arizona. Heavy rain, hail, and gusty/erratic outflow winds will be
the primary threats from storm development.

OUTLOOK...Friday 19/00Z through Sunday 21/00Z...Expect daily
SHRA/TSRA chances mostly in the afternoon/evening hours. Gusty and
erratic winds likely from storm development, with NW winds
generally less than 15 kts otherwise. VFR conditions will persist
outside of MVFR conditions from showers/storms.

&&

.FIRE WEATHER...Thursday and Friday...Isolated to scattered showers
and storms (most numerous over the higher terrain) are expected each
afternoon and evening. Gusty and erratic outflow winds, small hail,
and heavy rainfall remain the main hazards. Winds generally variable
5 to 15 mph, along with near to slightly above normal temperatures.

Saturday through Monday...Isolated to scattered showers and storms
will continue each afternoon and evening. Gusty and erratic outflow
winds, small hail, and heavy rainfall remain the main hazards. Winds
generally variable 5 to 15 mph, along with near to slightly above
normal temperatures.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...None.

&&

PUBLIC...BAK
AVIATION...Konieczny
FIRE WEATHER...BAK

For Northern Arizona weather information visit
weather.gov/flagstaff

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 16, 6:39 PM MSTSevere Thunderstorm WarningFGZCoconino, Gila, Yavapai36 min
Jul 16, 7:12 PM MSTSevere Thunderstorm WarningFGZCoconino, Gila, Yavapai48 min
Jul 16, 7:20 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino, Gila, Yavapai3 hr
Jul 17, 3:47 PM MSTSevere Thunderstorm WarningFGZGila, Yavapai26 min
Jul 17, 4:05 PM MSTSevere Thunderstorm WarningFGZYavapai25 min

Nearby

Flash Flood Warnings in Arizona, 2024Every flash flood warning in 2024

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.