Alert archive / Arizona / Special Weather Statements in 2021

Special Weather Statement, NWS Flagstaff, AZ

August 12, 2021Yavapai County, Arizona

NWS Flagstaff, AZ issued this special weather statement at Aug 12, 2021, 3:21 PM MST for Yavapai County, Arizona. It was in force for 24 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 12, 2021, 3:21 PM MST (22:21 UTC)
Expired
Aug 12, 2021, 3:45 PM MST
In force
24 min
Issued by
NWS Flagstaff, AZ
Hail
0.50 in
Wind
40

County Yavapai County, AZ

The radar

The Flagstaff radar (KFSX), 110 km from the middle of the area, began a volume at 22:25 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, 10.4 hours before the alert went out and 71 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 2021-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 40 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 12:00Z on 2021-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 53 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
40 J/kg
Mixed-layer CIN
-119 J/kg
Mixed-layer LCL
1538 m above ground
0-6 km bulk shear
3 kt
0-1 km storm-relative helicity
53 m²/s²
0-3 km storm-relative helicity
62 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

560 
WWUS85 KFGZ 122221
SPSFGZ

Special Weather Statement
National Weather Service Flagstaff AZ
321 PM MST Thu Aug 12 2021
 
AZZ008-037-122245-
Yavapai County Valleys and Basins-Yavapai County  Mountains-
321 PM MST Thu Aug 12 2021

...A strong thunderstorm will impact portions of Yavapai County
through 345 PM MST...

At 320 PM MST, Doppler radar was tracking a strong thunderstorm near
Chino Valley, moving west at 15 mph.

HAZARD...Winds in excess of 40 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...
Chino Valley and Williamson Valley. 

This includes State Route 89 between mile markers 325 and 336.

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 3483 11226 3471 11227 3470 11255 3489 11253
TIME...MOT...LOC 2220Z 097DEG 11KT 3478 11238 

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

$$

Humphreys

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 11, 5:35 PM MSTFlash Flood Warning Considerable damage threatFGZNavajo3 hr
Aug 12, 5:36 AM MSTFlash Flood Warning Considerable damage threatFGZGila3 hr
Aug 12, 12:34 PM MSTSpecial Weather StatementFGZYavapai26 min
Aug 12, 12:43 PM MSTSpecial Weather StatementFGZ32 min
Aug 12, 1:08 PM MSTSpecial Weather StatementFGZ22 min
Aug 12, 1:29 PM MSTSpecial Weather StatementFGZ31 min
Aug 12, 3:41 PM MSTFlash Flood Warning Considerable damage threatFGZCoconino6 hr

Nearby

Special Weather Statements in Arizona, 2021Every special weather statement 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.