Alert archive / Arizona / Severe Thunderstorm Warnings in 2024

Severe Thunderstorm Warning 6, NWS Tucson, AZ

June 21, 2024Pinal County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Jun 21, 2024, 5:09 PM MST for Pinal County, Arizona. It was in force for 36 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
Jun 21, 2024, 5:09 PM MST (00:09 UTC)
Expired
Jun 21, 2024, 5:45 PM MST
In force
36 min
Issued by
NWS Tucson, AZ
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Pinal County, AZ

The radar

The Phoenix radar (KIWA), 52 km from the middle of the area, began a volume at 00:10 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.

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 Jun 21, 1:28 PM MST, 3 hours 41 minutes earlier.

Area forecast discussion, Jun 21, 1:28 PM MST, 3 hours 41 minutes before
Area Forecast Discussion
National Weather Service Tucson AZ
128 PM MST Fri Jun 21 2024

.SYNOPSIS...A strong increase in moisture will bring daily chances of
thunderstorms to the area into next week. Some storms will
generate strong outflow winds with locally heavy rain possible.
This will also knock several degrees off of the heat. We may see
temperatures climb back up a bit as high pressure settles
overhead next week.

&&

.DISCUSSION...Partly to mostly cloudy skies early this afternoon
across southeast Arizona with considerable mid and high level
cloudiness. We're now seeing cumulus clouds developing due to the
heating, moisture and instability across the region as PWAT values
range from 1 to 1.5 inches across the area. Gusty east to southeast
winds continue this afternoon but wind speeds have certainly
diminished compared to yesterday and earlier this morning. HREF/CAMs
are showing convective development this afternoon primarily in a
north-south zone across central portions of the forecast area. The
center of this line would be from around Nogales-Tucson-Kearny.
MLCAPE values are locally in the 1000-1500 J/KG range this afternoon
per the latest RAP mesoanalysis with DCAPE values near 2000 J/KG.
This will result in strong/gusty outflow winds from the thunderstorm
activity that does develop. In addition, some locally heavy rainfall
of around 0.5"-1" is expected with the stronger storms. The
convection will make it a bit farther west today compared to
yesterday as greater moisture levels allow additional westward
development on outflow boundaries. In addition, some areas of
blowing dust may occur primarily in Pinal County due to gusty
outflow winds. A few of the CAMs are persisting shower activity into
the overnight but stronger thunderstorms will mainly occur through
the afternoon into early evening.

Additional moisture will move into the area tonight and Saturday
from Sonora and the Gulf of California. This will raise the PWAT
values this weekend into the 1.25" (eastern areas) to around 2"
(western deserts). These are very anomalous for late June, running
about 3 to 4 standard deviations above normal. With abundant
moisture and the mid/upper level high to our east, our region will
continue to see a favorable steering flow from the southeast. That
combination of deep moisture, favorable steering and instability
will result in scattered mainly afternoon and evening showers and
thunderstorms this weekend for the entire forecast area. The
stronger storms will have both wind and localized flooding threats,
as rain amounts in excess of 1 inch are possible with the stronger
storms. Temperatures will drop back down to seasonable levels this
weekend.

For Monday and continuing through next week, the mid/upper level
high will gradually strengthen and shift a bit closer to southeast
Arizona. Therefore, while the moisture isn't going anywhere and will
be recycled each day, the mid/upper level high location and
potential subsidence will tend to shift the focus of convective
activity a bit closer to the higher terrain overall with the better
chances starting to focus a slightly more towards areas from Tucson
south and eastward. Temperatures will nudge back up next week,
running a few degrees above normal.

&&

.AVIATION...Valid through 23/00Z.
SCT-BKN clouds 10-14k ft AGL. SCT -TSRA will with TSRA and BKN CIGS
around 6k ft AGL possible thru 22/03Z. Sct -SHRA then possible
overnight but confidence is low. East to southeast winds 10-20 kts,
diminishing after 22/03Z. Stronger and erratic outflows possible
with storms. Additional SCT -TSRA activity expected aft 22/18Z thru
the end of the period. Aviation discussion not updated for TAF
amendments.

&&

.FIRE WEATHER...Gusty east to southeast winds continue to diminish
this afternoon. A strong increase in moisture will bring better RH
values along with a chance of thunderstorms into at least early next
week. Some storms will generate strong and erratic outflow winds.
Moisture is expected to be deep enough for some storms to generate
locally heavy rain.

Temperatures may heat back up by mid week as high pressure builds
nearly overhead, however we should keep some storm chances around.

&&

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

&&

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

In the hours before

Local storm report, Jun 21, 2:45 PM MST, 2 hours 24 minutes before
Preliminary Local Storm Report
National Weather Service Tucson AZ
245 PM MST Fri Jun 21 2024

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

0237 PM     Non-Tstm Wnd Gst 6 SW Tucson             32.13N 110.95W
06/21/2024  M62 MPH          Pima               AZ   ASOS

            ASOS station KTUS Tucson International
            Airport.

&&
Local storm report, Jun 21, 2:46 PM MST, 2 hours 23 minutes before
Preliminary Local Storm Report
National Weather Service Tucson AZ
246 PM MST Fri Jun 21 2024

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

0237 PM     Tstm Wnd Gst     6 SW Tucson             32.13N 110.95W
06/21/2024  M62 MPH          Pima               AZ   ASOS

            Corrects previous non-tstm wnd gst report
            from 6 SW Tucson. ASOS station KTUS Tucson
            International Airport.

&&

JVT
Local storm report, Jun 21, 2:54 PM MST, 2 hours 15 minutes before
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Local storm report, Jun 21, 3:07 PM MST, 2 hours 2 minutes before
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  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
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  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

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

IssuedProductOfficeCountiesLasted
Jun 21, 6:51 PM MSTAreal Flood AdvisoryTWCCochise114 min
Jun 22, 2:12 PM MSTAreal Flood AdvisoryTWCPima2 hr
Jun 22, 2:50 PM MSTFlash Flood Warning Considerable damage threatTWCPima3 hr
Jun 22, 3:35 PM MSTAreal Flood AdvisoryTWCPima, Pinal115 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2024Every severe thunderstorm warning in 2024

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; radar from the NEXRAD Level II archive.