Alert archive / Arizona / Special Weather Statements in 2021

Special Weather Statement, NWS Tucson, AZ

July 17, 2021Graham County, Arizona

NWS Tucson, AZ issued this special weather statement at Jul 17, 2021, 8:04 PM MST for Graham County, Arizona. It was in force for 41 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 17, 2021, 8:04 PM MST (03:04 UTC)
Expired
Jul 17, 2021, 8:45 PM MST
In force
41 min
Issued by
NWS Tucson, AZ

County Graham County, AZ

The radar

The Tucson radar (KEMX), 110 km from the middle of the area, began a volume at 03:04 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, 3.1 hours before the alert went out and 116 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 2021-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 59 joules per kilogram.LCLLFCEL10008507005003002001001 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 2021-07-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 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
59 J/kg
Mixed-layer CIN
-28 J/kg
Mixed-layer LCL
2570 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
91 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.2

Open this sounding in Storm Lab

The text

As transmitted.

216 
WWUS85 KTWC 180304
SPSTWC

Special Weather Statement
National Weather Service Tucson AZ
804 PM MST Sat Jul 17 2021
 
AZZ508-509-511-180345-
Upper Gila River and Aravaipa Valleys including
Clifton/Safford-Eastern Cochise County Below 5000 Feet including
Douglas/Willcox-Galiuro and Pinaleno Mountains including Mount
Graham-
804 PM MST Sat Jul 17 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTH CENTRAL GRAHAM AND NORTH
CENTRAL COCHISE COUNTIES UNTIL 845 PM MST...

At 804 PM MST, Doppler radar was tracking a strong thunderstorm 16
miles northeast of Willcox, moving northwest at 25 mph.

Dime size hail will be possible with this storm.

Locations impacted include...
Fort Grant, Mount Graham and Bonita. 

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.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3245 10955 3234 10976 3258 11003 3279 10978
TIME...MOT...LOC 0304Z 149DEG 20KT 3246 10972 

$$

Singer

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 17, 6:50 PM MSTSpecial Weather StatementTWCCochise25 min
Jul 17, 8:28 PM MSTSpecial Weather StatementTWCCochise32 min
Jul 18, 6:19 AM MSTSpecial Weather StatementTWCSanta Cruz41 min
Jul 18, 7:55 AM MSTAreal Flood AdvisoryTWCSanta Cruz3 hr
Jul 18, 11:57 AM MSTAreal Flood AdvisoryTWCCochise3 hr
Jul 18, 1:00 PM MSTAreal Flood AdvisoryTWCGraham109 min
Jul 18, 1:28 PM MSTFlash Flood WatchTWCCochise, Graham, Greenlee, Pima, Pinal, Santa Cruz11 hr
Jul 18, 2:36 PM MSTAreal Flood AdvisoryTWCGraham3 hr
Jul 18, 3:05 PM MSTSevere Thunderstorm WarningTWCGraham40 min
Jul 18, 3:36 PM MSTAreal Flood AdvisoryTWCGraham114 min
Jul 18, 4:08 PM MSTFlash Flood Warning Considerable damage threatTWCGreenlee112 min
Jul 18, 4:10 PM MSTSpecial Weather StatementTWC35 min
Jul 18, 4:16 PM MSTAreal Flood AdvisoryTWCGraham, Greenlee119 min
Jul 18, 4:21 PM MSTAreal Flood AdvisoryTWCGraham114 min
Jul 18, 4:36 PM MSTFlash Flood Warning Considerable damage threatTWCGraham, Greenlee3 hr
Jul 18, 4:45 PM MSTAreal Flood AdvisoryTWCCochise2 hr
Jul 18, 4:50 PM MSTSevere Thunderstorm WarningTWCCochise40 min
Jul 18, 4:58 PM MSTFlash Flood Warning Considerable damage threatTWCCochise2 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.