Alert archive / Arizona / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 13, NWS Flagstaff, AZ

July 18, 2026Navajo County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Jul 18, 2026, 6:30 PM MDT for Navajo County, Arizona. It was in force for 30 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 18, 2026, 6:30 PM MDT (00:30 UTC)
Expired
Jul 18, 2026, 7:00 PM MDT
In force
30 min
Issued by
NWS Flagstaff, AZ
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Navajo County, AZ

The radar

The Flagstaff radar (KFSX), 97 km from the middle of the area, began a volume at 00:33 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 00:00Z, 0.5 hours before the alert went out and 152 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, Flgstf/Belemont, AZ at 00:00Z on 2026-07-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 138 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 00:00Z on 2026-07-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 51 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
138 J/kg
Mixed-layer CIN
-43 J/kg
Mixed-layer LCL
1075 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
51 m²/s²
0-3 km storm-relative helicity
65 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.6

Open this sounding in Storm Lab

The text

As transmitted.

871 
WUUS55 KFGZ 190030
SVRFGZ
AZC017-190100-
/O.NEW.KFGZ.SV.W.0013.260719T0030Z-260719T0100Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Flagstaff AZ
530 PM MST Sat Jul 18 2026

The National Weather Service in Flagstaff has issued a

* Severe Thunderstorm Warning for...
  Navajo County in north central Arizona...

* Until 600 PM MST.

* At 530 PM MST, severe thunderstorms were located along a line from
  8 miles north of Hibbard to 6 miles southeast of Woodruff, or along
  a line from 13 miles east of Winslow to 33 miles north of Show Low,
  moving southwest at 10 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage to
           roofs, siding, and trees.

* Locations impacted include...
  Joseph City, Woodruff, Manila, Hibbard and Jackrabbit.

This includes the following highways...
Interstate 40 between mile markers 266 and 283. Business Interstate
40 between mile markers 275 and 276. State Route 377 between mile
markers 22 and 33. State Route 77 between mile markers 368 and 385.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Seek shelter inside a well-built structure and stay away from
windows. These storms are capable of producing damaging winds and
large hail.

&&

LAT...LON 3509 11036 3487 11018 3477 10985 3473 10985
      3459 11006 3475 11034 3504 11056
TIME...MOT...LOC 0030Z 63DEG 8KT 3508 11048 3485 11021 3472 10995

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Bernhart
1 follow-up statement
235 
WWUS55 KFGZ 190055
SVSFGZ

Severe Weather Statement
National Weather Service Flagstaff AZ
555 PM MST Sat Jul 18 2026

AZC017-190105-
/O.EXP.KFGZ.SV.W.0013.000000T0000Z-260719T0100Z/
Navajo AZ-
555 PM MST Sat Jul 18 2026

...SEVERE THUNDERSTORM WARNING WILL EXPIRE AT 6 PM MST FOR NAVAJO
COUNTY...

The storms which prompted the warning have weakened below severe
limits, and have exited the warned area. Therefore, the warning will
be allowed to expire. However, heavy rain is still possible with
these thunderstorms.

&&

LAT...LON 3509 11036 3487 11018 3477 10985 3473 10985
      3459 11006 3475 11034 3504 11056
TIME...MOT...LOC 0030Z 63DEG 8KT 3508 11049 3485 11021 3472 10996

$$

Bernhart

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 Flagstaff, AZ wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 18, 4:37 PM MDT, 1 hour 53 minutes earlier.

Area forecast discussion, Jul 18, 4:37 PM MDT, 1 hour 53 minutes before
Area Forecast Discussion
National Weather Service Flagstaff AZ
337 PM MST Sat Jul 18 2026

.SYNOPSIS...Deep monsoonal moisture will remain over the area
through this weekend and well into next week. With this moisture
comes the daily threat of thunderstorms, along with the risk for
locally heavy rainfall and flooding. With the added moisture and
cloud cover, daytime temperatures will remain below normal.

&&

.DISCUSSION...We are locked in a pattern that shows no signs of
changing and considering how badly the region needs water, this is
largely a good thing. The region will remain in a very moist air
mass, even with respect to the Monsoon Season, with both PW and
surface dew point values about as high as is possible. Northeast
through easterly steering flow will also persist, at least into
early next week. This steering flow may transition to more of a
southeasterly direction later next week.

The current steering flow heavily favors locations just to the
southwest, south and west of the central Mogollon Rim. A secondary
area usually forms later each day across Apache and Navajo counties
or over western New Mexico. These secondary areas are what supports
nocturnal convection, which should be more active tonight than
last night. This is evident in the latest model guidance aided by
increased sun over northeast AZ this morning.

Despite all the favorable mechanisms to produce heavy rain, we are
also seeing large areas of rain-cooled air, rain-cooled ground and
extensive debris cloud cover each day/night. These factors can
prevent stronger and more widespread convection from forming and
therefore limit the amount of storms that can produce flash
flooding. This and the lack of any clear forcing mechanism will
keep FFA issuances away for another day, at least. By early next
week, an easterly wave may improve shear and storm motion,
potentially raising the risk for flash flooding and hail
production.

&&

.AVIATION...Sunday 19/00Z through Monday 20/00Z...Rounds of
SHRA/TSRA will continue through the evening hours becoming
isolated after 06Z. Stronger storm cells will produce brief MVFR
and IFR conditions.  Outside of thunderstorms, expect light winds
5-10 kts. Another active day of monsoon storms is in store on
Sunday. Expect scattered to numerous SHRA/TSRA with isolated +TSRA
from late Sunday morning through the afternoon. The primary
threat will be MVFR to IFR conditions in heavy rain. Gusty outflow
winds up to 40 kts and hail are also possibilities.

OUTLOOK...Monday 20/00Z through Wednesday 22/00Z...Expect
scattered to numerous SHRA/TSRA and isolated +TSRA each day,
storms most numerous in the afternoon hours. Any stronger storms
will produce brief MVFR to IFR conditions. Some IFR low clouds
and fog possible, mainly for overnight hours. Outside of storms,
expect light winds around 5-10 kts.

&&

.FIRE WEATHER...Sunday and Monday...Expect a continuation of the
active monsoon pattern into next week with rounds of showers and
thunderstorms each day. Primary storm concerns will be heavy rain
and flash flooding, though erratic outflow winds are also possible.
Outside of storms activity, expect light winds.

Tuesday through Thursday...Active monsoon conditions continue with
daily chances for showers and thunderstorms, Expect generally light
winds outside of any storms. Most storms will produce wetting rain
with isolated to scattered flash flooding.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...None.

&&

PUBLIC...Zanker
AVIATION...McCollum
FIRE WEATHER...MCT

For Northern Arizona weather information visit
weather.gov/flagstaff

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 18, 6:03 PM MDTSevere Thunderstorm WarningFGZNavajo27 min
Jul 18, 7:58 PM MDTFlash Flood Warning Considerable damage threatFGZCoconino3 hr
Jul 18, 8:49 PM MDTFlash Flood Warning Considerable damage threatFGZCoconino3 hr
Jul 18, 10:11 PM MDTFlash Flood Warning Considerable damage threatFGZCoconino3 hr
Jul 19, 2:04 PM MDTFlash Flood Warning Considerable damage threatFGZApache3 hr
Jul 19, 4:39 PM MDTSevere Thunderstorm WarningFGZCoconino36 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2026Every severe thunderstorm warning in 2026

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.