Alert archive / Arizona / Severe Thunderstorm Warnings in 2025

Severe Thunderstorm Warning 65, NWS Phoenix, AZ

September 17, 2025Yuma County, Arizona

NWS Phoenix, AZ issued this severe thunderstorm warning at Sep 17, 2025, 4:44 PM MST for Yuma County, Arizona. It was in force for 31 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: Sep 17, 2025, 4:44 PM MST (23:44 UTC)
Expired: Sep 17, 2025, 5:15 PM MST
In force: 31 min
Issued by: NWS Phoenix, AZ
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Yuma County, AZ

The radar

The Yuma radar (KYUX), 77 km from the middle of the area, began a volume at 23:44 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

Yuma Prvg Ground, AZ (K1Y7), launched 12:00Z, 11.7 hours before the alert went out and 55 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 629 J/kg
Mixed-layer CIN: -114 J/kg
Mixed-layer LCL: 1858 m above ground
0-6 km bulk shear: 7 kt
0-1 km storm-relative helicity: 22 m²/s²
0-3 km storm-relative helicity: 51 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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 Phoenix, AZ wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 17, 4:40 PM MST, 4 minutes earlier.

Area forecast discussion, Sep 17, 4:40 PM MST, 4 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <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.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

In the hours before

Special weather statement, Sep 17, 1:05 PM MST, 3 hours 39 minutes before

Special Weather Statement
National Weather Service Phoenix AZ
105 PM PDT Wed Sep 17 2025

CAZ564-568-570-172045-
Chuckwalla Mountains CA-Chuckwalla Valley CA-Chiriaco Summit CA-
105 PM PDT Wed Sep 17 2025

...A STRONG THUNDERSTORM WILL IMPACT RIVERSIDE COUNTY THROUGH 145 PM
PDT...

At 105 PM PDT, Doppler radar was tracking a strong thunderstorm 8
miles southwest of Desert Center. This thunderstorm was nearly
stationary.

HAZARD...Wind gusts up to 50 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Desert Center.

This includes the following highways...
CA Interstate 10 between mile markers 93 and 108.
CA Route 177 between mile markers 1 and 2.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3354 11535 3352 11558 3372 11563 3374 11533
TIME...MOT...LOC 2005Z 177DEG 1KT 3361 11547

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

TW

Special weather statement, Sep 17, 1:30 PM MST, 3 hours 14 minutes before

Special Weather Statement
National Weather Service Phoenix AZ
130 PM MST Wed Sep 17 2025

AZZ533-172100-
Central La Paz AZ-
130 PM MST Wed Sep 17 2025

...A STRONG THUNDERSTORM WILL IMPACT CENTRAL LA PAZ COUNTY THROUGH
200 PM MST...

At 130 PM MST, Doppler radar was tracking a strong thunderstorm 7
miles northwest of Kofa Wildlife Refuge, or 39 miles south of Parker.
This thunderstorm was nearly stationary.

HAZARD...Wind gusts up to 50 mph and pea size 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...
Quartzsite.

This includes the following highways...
AZ Interstate 10 between mile markers 18 and 34.
US Highway 60 between mile markers 31 and 34.
AZ Route 95 between mile markers 97 and 110.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3351 11396 3351 11421 3369 11424 3370 11396
TIME...MOT...LOC 2030Z 180DEG 1KT 3359 11409

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH

TW

Special weather statement, Sep 17, 2:06 PM MST, 2 hours 38 minutes before

Special Weather Statement
National Weather Service Phoenix AZ
206 PM PDT Wed Sep 17 2025

CAZ564-570-172130-
Chuckwalla Mountains CA-Chuckwalla Valley CA-
206 PM PDT Wed Sep 17 2025

...A STRONG THUNDERSTORM WILL IMPACT RIVERSIDE COUNTY THROUGH 230 PM
PDT...

At 206 PM PDT, Doppler radar was tracking a strong thunderstorm 14
miles south of Desert Center. This thunderstorm was nearly
stationary.

HAZARD...Wind gusts up to 50 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

This storm will remain over mainly rural areas of Riverside County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3364 11520 3343 11523 3343 11546 3362 11552
      3364 11551
TIME...MOT...LOC 2106Z 180DEG 2KT 3351 11534

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH

TW

Special weather statement, Sep 17, 2:15 PM MST, 2 hours 29 minutes before

Special Weather Statement
National Weather Service Phoenix AZ
215 PM PDT Wed Sep 17 2025

CAZ564-568-172145-
Chuckwalla Mountains CA-Chiriaco Summit CA-
215 PM PDT Wed Sep 17 2025

...A STRONG THUNDERSTORM WILL IMPACT RIVERSIDE COUNTY THROUGH 245 PM
PDT...

At 215 PM PDT, Doppler radar was tracking a strong thunderstorm 10
miles southeast of Chiriaco Summit. This thunderstorm was nearly
stationary.

HAZARD...Wind gusts up to 50 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

This storm will remain over mainly rural areas of Riverside County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 3346 11548 3346 11572 3365 11575 3366 11547
TIME...MOT...LOC 2115Z 176DEG 1KT 3355 11560

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH

TW

Special weather statement, Sep 17, 4:33 PM MST, 11 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <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.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 17, 12:39 PM MST	Flood Watch	PSR	La Paz, Yuma	34 hr
Sep 17, 1:30 PM MST	Special Weather Statement	PSR	La Paz	30 min
Sep 17, 2:36 PM MST	Severe Thunderstorm Warning	PSR	La Paz, Yuma	39 min
Sep 17, 3:29 PM MST	Areal Flood Advisory	PSR	La Paz	3 hr
Sep 17, 4:33 PM MST	Special Weather Statement	PSR	Yuma	27 min
Sep 17, 1:05 PM MST	Special Weather Statement	PSR	Riverside	40 min
Sep 17, 2:06 PM MST	Special Weather Statement	PSR	Imperial	24 min
Sep 17, 2:15 PM MST	Special Weather Statement	PSR	Riverside	30 min
Sep 17, 2:30 PM MST	Severe Thunderstorm Warning	PSR	Riverside	45 min
Sep 17, 2:45 PM MST	Severe Thunderstorm Warning	PSR	Riverside	24 min
Sep 17, 2:59 PM MST	Flash Flood Warning Considerable damage threat	PSR	Riverside	3 hr
Sep 17, 3:22 PM MST	Severe Thunderstorm Warning	PSR	Imperial, Riverside	38 min
Sep 17, 4:06 PM MST	Areal Flood Advisory	PSR	Imperial, Riverside	3 hr
Sep 17, 4:51 PM MST	Special Weather Statement	PSR	Imperial	24 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2025 Every severe thunderstorm warning in 2025

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.