Alert archive / Arizona / Areal Flood Warnings in 2021
Areal Flood Warning 6, NWS Flagstaff, AZ
NWS Flagstaff, AZ issued this areal flood warning at Aug 18, 2021, 10:41 PM MST for Gila County, Yavapai County, Arizona. It was in force for 10 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 18, 2021, 10:41 PM MST (05:41 UTC)
- Expired
- Aug 19, 2021, 8:30 AM MST
- In force
- 10 hr
- Issued by
- NWS Flagstaff, AZ
- Area
- Storm-based polygon
- Flood severity
- None
Counties Gila County, AZ, Yavapai County, AZ
The radar
The Flagstaff radar (KFSX), 61 km from the middle of the area, began a volume at 05:41 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, 5.7 hours before the alert went out and 90 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.
- Mixed-layer CAPE
- 510 J/kg
- Mixed-layer CIN
- -174 J/kg
- Mixed-layer LCL
- 1692 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 157 m²/s²
- 0-3 km storm-relative helicity
- 230 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 1.7
What forecasters said that day
The local office's own words before this areal 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 areal flood warning went out at Aug 18, 8:32 PM MST, 2 hours 9 minutes earlier.
Area forecast discussion, Aug 18, 8:32 PM MST, 2 hours 9 minutes before
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Special weather statement, Aug 18, 5:31 PM MST, 5 hours 10 minutes before
Special Weather Statement
National Weather Service Flagstaff AZ
531 PM MST Wed Aug 18 2021
AZZ008-037-190100-
Yavapai County Valleys and Basins-Yavapai County Mountains-
531 PM MST Wed Aug 18 2021
...A strong thunderstorm will impact portions of Yavapai County
through 600 PM MST...
At 530 PM MST, Doppler radar was tracking a strong thunderstorm over
Iron Springs, or 9 miles west of Prescott Valley, moving northeast at
15 mph.
HAZARD...Winds in excess of 30 mph and half inch hail.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor damage to outdoor objects is
possible.
Locations impacted include...
Prescott Valley, Prescott, Dewey-humboldt, Groom Creek Subdivision,
Prescott Airport, Prescott Gateway Mall, Iron Springs, Yavapai
Campground, Downtown Prescott, Ponderosa Park, Indian Hill West
Prescott, Oak Knoll Village, Wilhoit, Lynx Lake Dam, Prescott Valley
Event Center and White Spar Campground.
This includes the following highways...
State Route 89 near mile marker 295, and between mile markers 299
and 325.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
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 11259 3458 11269 3476 11240 3452 11224
TIME...MOT...LOC 0030Z 242DEG 15KT 3454 11256
MAX HAIL SIZE...0.50 IN
MAX WIND GUST...30 MPH
DBLocal storm report, Aug 18, 6:33 PM MST, 4 hours 8 minutes before
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</html>Local storm report, Aug 18, 7:07 PM MST, 3 hours 34 minutes before
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</html>Local storm report, Aug 18, 7:32 PM MST, 3 hours 9 minutes before
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</html>Local storm report, Aug 18, 7:33 PM MST, 3 hours 8 minutes before
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</p>
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Please try again in a few minutes.
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</html>The office that day
Everything else NWS Flagstaff, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 18, 5:13 PM MST | Flash Flood Warning | FGZ | Yavapai | 3 hr |
| Aug 18, 5:17 PM MST | Flash Flood Warning | FGZ | Coconino, Yavapai | 4 hr |
| Aug 18, 5:31 PM MST | Special Weather Statement | FGZ | Yavapai | 29 min |
| Aug 18, 5:43 PM MST | Severe Thunderstorm Warning | FGZ | Coconino | 23 min |
| Aug 18, 7:59 PM MST | Flash Flood Warning | FGZ | Gila | 4 hr |
| Aug 18, 8:08 PM MST | Flash Flood Warning | FGZ | Yavapai | 6 hr |
| Aug 18, 11:56 PM MST | Flash Flood Warning | FGZ | Coconino | 8 hr |
Nearby
Areal Flood Warnings in Arizona, 2021Every areal flood warning in 2021
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.