368
FXUS65 KFGZ 181805
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
1105 AM MST Fri Apr 18 2025

.SYNOPSIS...A strong area of low pressure will move across Arizona
through Saturday, bringing areas of rain and snow today. Showers
shift to mainly eastern Arizona by Saturday. Warm and dry conditions
return from Sunday onward.

&&

.UPDATE...A band of showers containing heavy snow above 6500 feet has
developed over portions of northern Arizona. As a result, a
Winter Weather Advisory has been issued for the Western Mogollon
Rim (until 8:00 PM MST) and Black Mesa (until 9:00 PM MDT) Zones.
See products for details. As a cold front moves through, a band
of rain and snow showers spans CWA, and the forecasted snow levels
of around 6500-7000 ft look appropriate for today. Shower
activity has briefly stopped around the Flagstaff area as the
front stalls under zonal flow, but shower redevelopment is already
beginning along the I-40 corridor. Periods of heavier
precipitation could be expected before the front pushes southward
again after 3-5 pm MST. No changes to the forecast at this time.

&&

.PREV DISCUSSION /454 AM MST/...A cold front continues to drop
southward into northern Arizona early this morning accompanied
by rain and snow showers. Rain and snow showers will push
southward through this morning, with some increasing in intensity
as we move through the day. Mid-level flow is more zonal than
expected which will impact how fast the boundary moves through the
region. In fact, it looks like the front will stall by early
afternoon, which lends higher confidence to some of the more
recent wetter model runs as we may see redeveloping showers over
the same areas for several hours this afternoon. With QPF ranging
from around 0.50-1.00" there is the possibility of some
overproducing snow bands, though confidence on exactly where these
bands set up is not super high. A good portion of the higher
resolution models, including the AZWRF, have the redevelopment
occurring around the I-40 corridor, somewhere between Flagstaff
and Window Rock. With falling snow levels and cooling
temperatures, this could lead to snow covered roads and hazardous
travel conditions, especially through this afternoon and into this
evening. There is strong lift with this front and with marginal
instability across the region, there is the chance for some
thunder. Snow levels will also be around 6500-7000 feet through
much of the event. Though some of the more robust showers may help
drop them down to around 5000-5500 feet tonight. One of the
limiting factors for any additional headlines this morning is the
temperatures. With some warm air still around the area and the
surface temperatures on the warmer side, it is difficult to say
just how efficient we will be at accumulating snow or if we will
see a bit more rain mixing in at times affecting the snowfall
totals. With that in mind, we have kept the current headlines as
is with the caveat that it may be a bit dicey at times through the
I-40 corridor this afternoon/evening.

The front finally gets a much needed push from the reformed upper
low as it moves towards the south and west late tonight into
Saturday. With the low exiting into New Mexico by Saturday
afternoon, we should see the precipitation come to an end, from west
to east. Lingering showers into early Saturday evening may continue
across far eastern Arizona.

Sunday through much of the upcoming week...Zonal flow returns with
warming temperatures and a return to dry conditions. A few weak
shortwaves may cross the region through the week but they seem to
lack moisture and may end up resulting in breezier days with an
increase in some cloud cover.

&&

.AVIATION...Friday 18/18Z through Saturday 19/18Z...Expect
widespread rain and snow showers. Look for areas of MVFR and
local IFR conditions through the period. Overnight rain and snow
showers will taper off at western terminals but continue in the
eastern part of the state. Winds southwest to west at 15-25 kts
with gusts to 25-35 kts through 03Z, becoming light and variable.

OUTLOOK...Saturday 19/18Z through Monday 21/18Z...Local MVFR/IFR
conditions in rain/snow showers from KSOW-Four Corners eastward
through 00Z Sunday. Elsewhere, isolated showers possible. After
00Z Sunday improving conditions with widespread VFR conditions.
Winds northwest at 10-15 kts with gusts to 25 kts Saturday, light
and variable Sunday.

&&

.FIRE WEATHER...Today and Saturday...Today and Saturday...For today,
a band of rain and higher elevation snow will move across the
region. On Saturday, rain and snow will focus more on the eastern
half of Arizona. Wetting rain is likely for most locations between
today and Saturday. Winds southwest to west at 15-25 mph gusting
to 25-40 mph today, with the higher gusts mainly over east-central
Arizona. Winds northwest at 10- 15 mph gusting to 25 mph on
Saturday.

Sunday through Tuesday...Dry and turning warmer. Winds light and
variable Sunday becoming southwest at 10-15 mph Monday and
Tuesday.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 5 PM MST this afternoon for AZZ004.

Winter Weather Advisory until 5 PM MST /6 PM MDT/ Saturday for
AZZ011.

Winter Weather Advisory until 8 PM MST /9 PM MDT/ this evening
for AZZ015-039.

Winter Weather Advisory from 5 PM this afternoon to 5 PM MST
Saturday for AZZ017.

&&

$$

PUBLIC...Lewandowski/Meola
AVIATION...McCollum
FIRE WEATHER...McCollum

For Northern Arizona weather information visit
weather.gov/flagstaff