Alert archive / Arizona / Special Weather Statements in 2020

Special Weather Statement, NWS Flagstaff, AZ

July 23, 2020Navajo County, Arizona

NWS Flagstaff, AZ issued this special weather statement at Jul 23, 2020, 6:21 PM MDT for Navajo County, Arizona. It was in force for 39 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 23, 2020, 6:21 PM MDT (00:21 UTC)
Expired
Jul 23, 2020, 7:00 PM MDT
In force
39 min
Issued by
NWS Flagstaff, AZ

County Navajo County, AZ

The radar

The Flagstaff radar (KFSX), 170 km from the middle of the area, began a volume at 00:23 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

Flgstf/Belemont, AZ (KFGZ), launched 00:00Z, 0.4 hours before the alert went out and 157 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 2020-07-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2020-07-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 46 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2065 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
46 m²/s²
0-3 km storm-relative helicity
32 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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What forecasters said that day

The local office's own words before this special weather statement 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 special weather statement went out at Jul 23, 3:33 PM MDT, 2 hours 48 minutes earlier.

Area forecast discussion, Jul 23, 3:33 PM MDT, 2 hours 48 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.
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</body>
</html>

In the hours before

Special weather statement, Jul 23, 2:07 PM MDT, 4 hours 14 minutes before
Special Weather Statement
National Weather Service Flagstaff AZ
107 PM MST Thu Jul 23 2020

AZZ008-037-232030-
Yavapai County Valleys and Basins-Yavapai County  Mountains-
107 PM MST Thu Jul 23 2020

...SIGNIFICANT WEATHER ADVISORY NORTH OF PRESCOTT VALLEY IN YAVAPAI
COUNTY UNTIL 130 PM MST...

At 107 PM MST, Doppler radar was tracking a strong thunderstorm near
Yavapai County Fairgrounds, or 9 miles east of Chino Valley, moving
north at 5 mph.

Penny size hail and winds in excess of 30 mph will be possible with
this storm.

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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3467 11222 3470 11238 3485 11235 3481 11214
TIME...MOT...LOC 2007Z 192DEG 4KT 3472 11230

TPS
Special weather statement, Jul 23, 2:35 PM MDT, 3 hours 46 minutes before
Special Weather Statement
National Weather Service Flagstaff AZ
135 PM MST Thu Jul 23 2020

AZZ004-005-009-232115-
Kaibab Plateau-Marble and Glen Canyons-Northeast Plateaus and Mesas
Hwy 264 Northward-
135 PM MST Thu Jul 23 2020

...SIGNIFICANT WEATHER ADVISORY NEAR MARBLE CANYON AND LEES FERRY IN
COCONINO COUNTY UNTIL 215 PM MST/315 PM MDT/...

At 134 PM MST/234 PM MDT/, Doppler radar was tracking a strong
thunderstorm over Marble Canyon, or 13 miles southwest of Page,
moving north at 25 mph.

Nickel size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Lees Ferry, Wahweap and Marble Canyon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3700 11147 3670 11152 3670 11173 3700 11179
TIME...MOT...LOC 2034Z 179DEG 20KT 3678 11163

TPS
Local storm report, Jul 23, 2:58 PM MDT, 3 hours 23 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
158 PM MST THU JUL 23 2020

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

0157 PM     HEAVY RAIN       VERNON                  34.25N 109.69W
07/23/2020  M2.20 INCH       APACHE             AZ   PUBLIC

            MEMBER OF THE PUBLIC REPORTED 2.20 INCHES OF
            RAINFALL IN JUST OVER AN HOUR EARLY THIS
            AFTERNOON.

&&

TPS
Local storm report, Jul 23, 5:43 PM MDT, 38 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
443 PM MST THU JUL 23 2020

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

0425 PM     HEAVY RAIN       FOREST LAKES            34.34N 110.80W
07/23/2020  M0.82 INCH       COCONINO           AZ   TRAINED SPOTTER

            0.82 INCHES OF RAINFALL IN 25 MINUTES ENDING
            4:15 PM.

&&

41
Special weather statement, Jul 23, 5:46 PM MDT, 35 minutes before
Special Weather Statement
National Weather Service Flagstaff AZ
446 PM MST Thu Jul 23 2020

AZZ008-037-240015-
Yavapai County Valleys and Basins-Yavapai County  Mountains-
446 PM MST Thu Jul 23 2020

...SIGNIFICANT WEATHER ADVISORY FOR YAVAPAI COUNTY NEAR IRON SPRINGS
UNTIL 515 PM MST...

At 445 PM MST, Doppler radar was tracking a strong thunderstorm near
Iron Springs, or 14 miles west of Prescott Valley, moving north at 10
mph.

Penny size hail and wind gusts up to 45 mph will be possible with
this storm.

Locations impacted include...
Skull Valley and Iron Springs.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3449 11259 3450 11271 3465 11270 3463 11255
TIME...MOT...LOC 2345Z 199DEG 7KT 3457 11264

MCT
Special weather statement, Jul 23, 6:21 PM MDT, 0 minutes before
Special Weather Statement
National Weather Service Flagstaff AZ
621 PM MDT Thu Jul 23 2020

AZZ009-039-040-240100-
Black Mesa Area-Northeast Plateaus and Mesas Hwy 264 Northward-
Northeast Plateaus and Mesas South of Hwy 264-
621 PM MDT Thu Jul 23 2020

...SIGNIFICANT WEATHER ADVISORY FOR NAVAJO COUNTY UNTIL 700 PM
MDT/600 PM MST/...

At 620 PM MDT/520 PM MST/, Doppler radar was tracking strong
thunderstorms along a line extending from near Keams Canyon to 11
miles southwest of First Mesa. Movement was north at 10 mph.

Half inch hail and winds in excess of 40 mph will be possible with
these storms.

Locations impacted include...
Keams Canyon, First Mesa, Low Mountain, Jadito, Hard Rock,
Whippoorwill Chapter House, Jeddito, Navajo, Second Mesa, Polacca,
Shongopovi and Hopi Reservation.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3608 11003 3605 11055 3564 11066 3568 11011
TIME...MOT...LOC 0020Z 198DEG 10KT 3585 11023 3574 11055

MCT

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 23, 6:00 PM MDTAreal Flood AdvisoryFGZCoconino3 hr
Jul 23, 7:25 PM MDTSpecial Weather StatementFGZYavapai20 min
Jul 23, 8:16 PM MDTSpecial Weather StatementFGZYavapai29 min
Jul 23, 8:29 PM MDTAreal Flood AdvisoryFGZYavapai118 min
Jul 23, 9:49 PM MDTFlash Flood Warning Considerable damage threatFGZYavapai107 min

Nearby

Special Weather Statements in Arizona, 2020Every special weather statement in 2020

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.