Alert archive / Arizona / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 77, NWS Tucson, AZ

August 7, 2023Graham County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Aug 7, 2023, 3:57 PM MST for Graham County, Arizona. It was in force for 48 min. 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 7, 2023, 3:57 PM MST (22:57 UTC)
Expired
Aug 7, 2023, 4:45 PM MST
In force
48 min
Issued by
NWS Tucson, AZ
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Graham County, AZ

The radar

The Tucson radar (KEMX), 135 km from the middle of the area, began a volume at 22:59 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 12:00Z, 11.0 hours before the alert went out and 127 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 12:00Z on 2023-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1420 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tuscon, AZ at 12:00Z on 2023-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -10 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
1420 J/kg
Mixed-layer CIN
-173 J/kg
Mixed-layer LCL
1681 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
-10 m²/s²
0-3 km storm-relative helicity
-11 m²/s²
Significant tornado parameter
0.0
Supercell composite
-1.3

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Tucson, AZ wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 7, 3:13 PM MST, 44 minutes earlier.

Area forecast discussion, Aug 7, 3:13 PM MST, 44 minutes before
Area Forecast Discussion
National Weather Service Tucson AZ
313 PM MST Mon Aug 7 2023

.SYNOPSIS...Somewhat more typical monsoon weather is expected
this week with temperatures running closer to normal with
scattered afternoon and evening thunderstorms across much of
southeast Arizona. Drying out over the weekend and heating back up
again Sunday into early next week.

&&

.DISCUSSION...Scattered strong to severe thunderstorms developed
rather quickly after 1230 pm mainly across Cochise county with
lots of nickel to quarter size hail reports. These storms
possibly being aided by a very weak upper level disturbance that
was near Nogales this afternoon.days for scattered
showers and thunderstorms each day through at least Thursday. Not
every will see rain but those that do, could be locally heavy. Outside of Cochise county its
pretty quiet even with the significant increase in moisture over
the past 24 hours. Most recent CAMS showing different solutions
on what might occur over the next 6-10 hours. Some runs have
strong outflow moving out of Sonora MX and developing elevated
storms as far north as Phoenix. Others do not. Thus went with a
blend of models, leaning toward the NBM, with scattered storms
this evening into early Tuesday morning.

Moisture hanging around for most the week with Tuesday and
Wednesday likely being the more active days. Interesting to note
that the mid-level remnants of TS Eugene will move into southern
California Thursday. Low-grade monsoon forecast Friday into the
weekend.

Temperatures this week will remain several degrees above normal
before starting to warm up a bit over the weekend. Models
suggesting a return to excessive heat levels with record or near
record highs early next week under another strong high over the
state.

&&

.AVIATION...Valid through 09/00Z.
SCT -SHRA/-TSRA for much of the valid period with storms
developing either along outflow boundaries thru 08/10z and then
again after 08/19z due to daytime heating. Erratic wind gusts to
45 kts with any -TSRA. Otherwise SFC winds NW-WLY 10-15 kts
gusting up to 25 kts thru 08/03Z and once again after 09/18z.
At other times winds will follow diurnal trends and generally
remain under 10 kts. Aviation discussion not updated for TAF
amendments.

&&

.FIRE WEATHER...Daily rounds of showers and thunderstorms each
afternoon through the weekend. Any storms that do form are capable
of producing erratic and gusty outflows. Daytime temperatures remain
a few degrees above normal before increasing this upcoming weekend
into early next week. Minimum RH in the lower elevations range
from 20-35% and 40-50% in the higher elevations today and
decreasing to 10-20% and 20-30% by the weekend.

&&

.CLIMATE...The consecutive day streak of highs 100 degrees or
hotter in Tucson now stands at 53 days. The probabilities thru
Friday of NOT hitting 100 degrees is less than 10% each day.
Looking ahead to early next week, the most recent probabilities
for hitting 110 degrees in Tucson is between 10% and 20%.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...None.

&&

Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson

In the hours before

Local storm report, Aug 7, 1:08 PM MST, 2 hours 49 minutes before
Preliminary Local Storm Report
National Weather Service Tucson AZ
108 PM MST Mon Aug 7 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0105 PM     Hail             6 ESE Sierra Vista      31.54N 110.23W
08/07/2023  E1.00 inch       Cochise            AZ   Public

            Quarter sized hail.

&&

GRG
Local storm report, Aug 7, 1:09 PM MST, 2 hours 48 minutes before
Preliminary Local Storm Report
National Weather Service Tucson AZ
109 PM MST Mon Aug 7 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0109 PM     Hail             6 SE Sierra Vista       31.50N 110.26W
08/07/2023  E1.00 inch       Cochise            AZ   Trained Spotter

            Quarter sized hail and 1in of rain in 45
            minutes.

&&

GRG
Local storm report, Aug 7, 1:36 PM MST, 2 hours 21 minutes before
Preliminary Local Storm Report
National Weather Service Tucson AZ
136 PM MST Mon Aug 7 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0115 PM     Hail             Sierra Vista            31.57N 110.32W
08/07/2023  E1.75 inch       Cochise            AZ   Public

            Photo of hail sent via social media.

&&

DVS

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 6, 5:12 PM MSTSevere Thunderstorm WarningTWCCochise, Santa Cruz48 min
Aug 6, 5:23 PM MSTAreal Flood AdvisoryTWCCochise, Santa Cruz3 hr
Aug 6, 5:40 PM MSTFlash Flood WarningTWCCochise, Santa Cruz3 hr
Aug 6, 5:54 PM MSTSevere Thunderstorm Warning Considerable damage threatTWCCochise, Santa Cruz35 min
Aug 6, 6:40 PM MSTSevere Thunderstorm WarningTWCSanta Cruz65 min
Aug 6, 7:01 PM MSTSpecial Weather StatementTWC44 min
Aug 6, 7:14 PM MSTAreal Flood AdvisoryTWCSanta Cruz2 hr
Aug 6, 7:26 PM MSTFlash Flood WarningTWCSanta Cruz3 hr
Aug 7, 12:52 PM MSTDust Storm AdvisoryTWCCochise3 hr
Aug 7, 12:55 PM MSTSevere Thunderstorm WarningTWCCochise35 min
Aug 7, 1:01 PM MSTSevere Thunderstorm WarningTWCCochise44 min
Aug 7, 1:02 PM MSTSevere Thunderstorm WarningTWCCochise43 min
Aug 7, 1:21 PM MSTAreal Flood AdvisoryTWCCochise2 hr
Aug 7, 1:25 PM MSTSevere Thunderstorm WarningTWCCochise33 min
Aug 7, 1:27 PM MSTFlash Flood Warning Considerable damage threatTWCCochise3 hr
Aug 7, 1:30 PM MSTAreal Flood AdvisoryTWCCochise109 min
Aug 7, 1:33 PM MSTSevere Thunderstorm Warning Considerable damage threatTWCCochise39 min
Aug 7, 1:56 PM MSTSevere Thunderstorm WarningTWCCochise34 min
Aug 7, 2:06 PM MSTSevere Thunderstorm WarningTWCCochise25 min
Aug 7, 2:32 PM MSTSevere Thunderstorm WarningTWCCochise43 min
Aug 7, 3:09 PM MSTSevere Thunderstorm WarningTWCGraham51 min
Aug 7, 3:59 PM MSTAreal Flood AdvisoryTWCGraham3 hr
Aug 7, 4:25 PM MSTFlash Flood Warning Considerable damage threatTWCGraham3 hr
Aug 7, 4:29 PM MSTSevere Thunderstorm WarningTWCPima28 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2023Every severe thunderstorm warning in 2023

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.