Alert archive / Arizona / Special Weather Statements in 2021

Special Weather Statement, NWS Tucson, AZ

July 20, 2021

NWS Tucson, AZ issued this special weather statement at Jul 20, 2021, 9:13 PM MST. It was in force for 62 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
Jul 20, 2021, 9:13 PM MST (04:13 UTC)
Expired
Jul 20, 2021, 10:15 PM MST
In force
62 min
Issued by
NWS Tucson, AZ

The radar

The Tucson radar (KEMX), 71 km from the middle of the area, began a volume at 04:15 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

Tuscon, AZ (KTUS), launched 00:00Z, 4.2 hours before the alert went out and 32 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, Tuscon, AZ at 00:00Z on 2021-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 712 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tuscon, AZ at 00:00Z on 2021-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 9 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
712 J/kg
Mixed-layer CIN
-15 J/kg
Mixed-layer LCL
2745 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
9 m²/s²
0-3 km storm-relative helicity
49 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

330 
WWUS85 KTWC 210413
SPSTWC

Special Weather Statement
National Weather Service Tucson AZ
913 PM MST Tue Jul 20 2021
 
AZZ502-504>506-514-210515-
Santa Catalina and Rincon Mountains including Mount
Lemmon/Summerhaven-Tohono O'odham Nation including Sells-Southeast
Pinal County including Kearny/Mammoth/Oracle-Tucson Metro Area
including Tucson/Green Valley/Marana/Vail-South Central Pinal County
including Eloy/Picacho Peak State Park-
913 PM MST Tue Jul 20 2021

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN PIMA AND
SOUTHEASTERN PINAL COUNTIES UNTIL 1015 PM MST...

At 912 PM MST, Doppler radar was tracking a strong thunderstorm near
Oro Valley, moving west at 15 mph.

Winds in excess of 45 mph will be possible with this storm, along 
with heavy rain.

Locations impacted include...
Northwest Tucson, Catalina, Oro Valley, Marana, Casas Adobes, 
Flowing Wells, Saddlebrooke, Tortolita, Catalina State Park, Saguaro 
National Park West, Catalina Foothills, Tucson Estates, Picture 
Rocks and Dove Mountain.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3253 11091 3227 11090 3221 11131 3257 11128
TIME...MOT...LOC 0412Z 089DEG 11KT 3245 11101 

$$

Meyer

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 20, 6:00 PM MSTAreal Flood AdvisoryTWCPima3 hr
Jul 20, 6:44 PM MSTSpecial Weather StatementTWC46 min
Jul 20, 7:17 PM MSTSpecial Weather StatementTWCSanta Cruz43 min
Jul 20, 8:02 PM MSTSevere Thunderstorm WarningTWCPinal58 min
Jul 20, 8:14 PM MSTSpecial Weather StatementTWC61 min
Jul 20, 8:17 PM MSTSevere Thunderstorm WarningTWCPima58 min
Jul 20, 8:40 PM MSTAreal Flood AdvisoryTWCPima2 hr
Jul 20, 8:46 PM MSTSevere Thunderstorm WarningTWCPima30 min
Jul 20, 9:24 PM MSTSevere Thunderstorm WarningTWCPima, Pinal51 min
Jul 20, 9:42 PM MSTAreal Flood AdvisoryTWCPima, Pinal2 hr
Jul 20, 9:53 PM MSTSevere Thunderstorm WarningTWCPinal52 min
Jul 21, 1:50 AM MSTFlash Flood WatchTWCCochise, Graham, Greenlee, Pima, Pinal, Santa Cruz5 days
Jul 21, 8:18 AM MSTBlowing Dust AdvisoryTWCPima, Pinal8 hr
Jul 21, 1:00 PM MSTSpecial Weather StatementTWCPima45 min
Jul 21, 1:12 PM MSTSevere Thunderstorm WarningTWCPima48 min
Jul 21, 1:38 PM MSTFlash Flood Warning Considerable damage threatTWCPima3 hr
Jul 21, 1:57 PM MSTSpecial Weather StatementTWCPima48 min
Jul 21, 2:09 PM MSTSpecial Weather StatementTWCPima51 min
Jul 21, 2:16 PM MSTSevere Thunderstorm WarningTWCPima44 min
Jul 21, 2:21 PM MSTDust Storm AdvisoryTWCPima, Pinal84 min
Jul 21, 2:51 PM MSTAreal Flood AdvisoryTWCPima3 hr
Jul 21, 3:01 PM MSTDust Storm WarningTWCPinal32 min

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.