Arizona, 2021Heavy Snow in Arizona, March 11 to 14, 2021
March 11 to 14, 2021 · NWS FGZ · 3 events in 3 counties and zones
A slow moving large area of low pressure brought precipitation over northern Arizona for several days. Some area received heavy amounts of snow.
Every event with a place to put it; 3 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
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- Hail
- Winter weather
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- Cold
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- Deaths
- 0
- Injuries
- 0
- Property damage
- None recorded
- Crop damage
- None recorded
- Events
- 3
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
A slow moving large area of low pressure brought precipitation over northern Arizona for several days. Some area received heavy amounts of snow.
What forecasters said that day
The local office's own words before the first event, 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 the first event at Mar 11, 2:27 PM MST, 2 hours 33 minutes earlier.
Area forecast discussion, Mar 11, 2:27 PM MST, 2 hours 33 minutes before
Area Forecast Discussion
National Weather Service Flagstaff AZ
227 PM MST Thu Mar 11 2021
.SYNOPSIS...An approaching low will bring rain and snow mainly
from Flagstaff westward through Friday afternoon, spreading
eastward by Friday night and Saturday. Hazardous winter travel
conditions possible at times above 4000 to 5000 feet. Dry and
warmer conditions are expected to return for Sunday.
&&
.DISCUSSION...The large and cold winter storm was sliding down the
California coast this afternoon, and is forecast to gradually make
a turn toward the east later tonight through Friday. Snow showers
today have been a bit more persistent than earlier expected for
some areas, mainly from central Yavapai County up through the
Flagstaff region. The main threat from these has been reductions
to visibility, but only minor and brief accumulation on roads due
to the higher March sun angle. Later tonight and into Friday as
the low moves into a more favorable position, large scale lift,
upslope flow, and instability are expected to produce more
widespread snow over Yavapai, northern Gila, and the southern half
of Coconino County including Flagstaff, Williams, Prescott, Mingus
Mtn, Happy Jack, Pine-Strawberry. Colder temperatures will also
lead to a higher threat of slick roads and for these reasons a
Winter Weather Advisory has been issued from 11 PM tonight through
6 PM Friday above 5500 feet for Yavapai, Northern Gila, Southern
Coconino. Instability on Friday could also lead to some isolated
thunderstorms as well, with brief periods of intense snowfall.
Friday night through Saturday - the low accelerates eastward,
which will tend to decrease additional snow amounts for Friday
night. On Saturday, moist and unstable northwesterly flow will
lead to snow showers focused on the higher terrain and some
additional accumulations of up to a couple inches will be
possible. Saturday remains cold as well, with high country
temperatures likely topping out near freezing.
Sunday through next week - dry and warmer conditions expected
Sunday. Still some uncertainty for Monday/Tuesday as the next
system moves through. Right now our forecast shows a brief cool
down, increasing winds, and a slight chance for showers mainly
from Flagstaff northward. Better agreement by mid to late next
week, with dry and warmer weather most likely.
&&
.AVIATION...For the 00Z package...Scattered rain and snow showers
will continue this evening, mainly along and west of a KPAN-KFLG-
K0V7 line. Expect occasional MVFR/IFR conditions in the heavier
showers. Southwest winds 10-20 kts with gusts to 25 kts during the
daytime hours. Shower coverage and intensity expected to increase
after 04Z-07Z and persist through Friday afternoon. The highest
coverage expected along/west of a KPAN-K0V7 line, with only isolated
coverage east of this line. Aviation discussion not updated for TAF
amendments.
&&
.FIRE WEATHER...A winter storm will affect the region through
Saturday with cold temperatures and accumulating snow at times above
4500 feet. Look for gusty southwesterly winds Friday, shifting to
west-northwesterly Saturday.
Sunday through Tuesday...Dry and warmer weather arrives for Sunday
with breezy west-northwest winds. Another weak system arrives late
Monday with a low chance showers and gusty southwest winds. Cool but
mainly dry Tuesday.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...Winter Weather Advisory from
11 PM this evening to 6 PM MST Friday FOR AZZ008-015-016-018-038.
&&
PUBLIC...JJ
AVIATION...JJ
FIRE WEATHER...JJ
For Northern Arizona weather information visit
weather.gov/flagstaff
In the hours before
Local storm report, Mar 11, 3:02 PM MST, 1 hour 58 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
302 PM MST THU MAR 11 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1131 AM SNOW 5 WSW PARKS 35.24N 112.04W
03/11/2021 M4.1 INCH COCONINO AZ PUBLIC
&&
JJLocal storm report, Mar 11, 4:51 PM MST, 9 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
451 PM MST THU MAR 11 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0432 PM SNOW 2 NNW DOWNTOWN FLAGSTAF 35.23N 111.67W
03/11/2021 M4.2 INCH COCONINO AZ NWS EMPLOYEE
4.2 INCHES OF NEW SNOW ON THE GROUND AT TIME
OF OBSERVATION.
&&Heavy Snow, Western Mogollon Rim
- When
- March 11, 5:00 PM MST to March 14, 4:00 AM MST
- Where
- Western Mogollon Rim forecast zone
- Reported by
- Trained Spotter
- Coordinates
- 35.839, -111.770 (the zone’s center; the record gives no point)
Snow began to fall over the Western Mogollon Rim late in the afternoon on March 11th. The snow continued to fall through the morning of March 14th. The heaviest snow fell during the first night of the event. Heavy snow criteria was met before noon on March 12th for many locations across the Western Mogollon Rim. Snow then continued to fall at lighter intensities into the early morning hours of March 14 before ending. Some of the snowfall totals include (in inches): Flagstaff and Kachina Village 12-17, Belelmont 11.5, 5WSW Parks 16.5, and Parks 11.8.
Heavy Snow, Oak Creek and Sycamore Canyons
- When
- March 11, 7:00 PM MST to March 12, 7:00 PM MST
- Where
- Oak Creek and Sycamore Canyons forecast zone
- Reported by
- COOP Observer
- Coordinates
- 35.220, -112.162 (the zone’s center; the record gives no point)
Slide Rock State Park (just below 5000 feet) reported 4 inches of snow by 330 PM on March 11th.
Heavy Snow, Northern Gila County
- When
- March 12, 6:00 PM MST to March 13, 10:30 PM MST
- Where
- Northern Gila County forecast zone
- Reported by
- Public
- Coordinates
- 33.800, -110.812 (the zone’s center; the record gives no point)
Two 2 inches fell overnight Friday into Saturday (March 12-13) and four 4 inches additional fell on Saturday evening. The elevation was just below 4,800 feet.
- Heavy Snow
- Snowfall reaching the local warning threshold without the other hazards of a winter storm.
After NWS Directive 10-1605, the rules offices file Storm Data by.
- Flash Flooding and Flooding in Missouri, March 11 to 15, 20210.75 in hail · 62 events
- Flash Flooding and Debris Flow in Hawaii, March 11 to 15, 202131 events
- Hail and Heavy Rain in Missouri, March 11, 20211 in hail · 5 events
- Hail and Damaging Wind in Missouri, March 11, 202161 kt wind · 2 events
- Flood and Damaging Wind in Missouri, March 11 to 14, 2021$1,000 · 52 kt wind · 2 events
- Flash Flood and Flood in Illinois, March 11, 2021$5,000 · 2 events
- Winter Weather in California, March 11 to 12, 20212 events
- Winter Weather in Nevada, March 11 to 12, 20212 events
- Heavy Snow in Nevada, March 11, 20211 event
- Flood in Puerto Rico, March 11, 20211 event
- Dense Fog in California, March 11 to 12, 20211 event
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 950622, 950623, 951212.