161
FXUS65 KFGZ 171604
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
904 AM MST Fri May 17 2024

.SYNOPSIS...Warmer and drier weather will return to northern
Arizona Friday through the weekend, with winds gradually
increasing each afternoon. Unsettled weather is possible next
week.

&&

.UPDATE...Sunny skies and warm temperatures are expected for
today, along with typical afternoon breezes, as high pressure
builds into the southwest.

Overnight forecast package is in good shape, with no changes
needed this morning. Previous discussion continues below.

&&

.PREV DISCUSSION /301 AM MST/...Clear skies were being observed
across Arizona in the early morning hours as a weak high pressure
system began to move in from the west. For today look for a bit
warmer daytime temperatures and afternoon west to southwest
breezes at a pretty typical 10 to 20 mph. Enough moisture will
linger across the area for a few afternoon fair weather cumulus
over the mountains.

For Saturday and Sunday...The high will move eastward as a long-
wave trough begins to build over the western states. The result
will be strengthening pressure gradients for stronger winds and a
distinct shift to a more southwesterly direction. Afternoon sustained
winds in the 10 to 20 mph range with gusts near 30 mph are likely
each day. It will remain dry.

On Monday and Tuesday...A stronger short-wave trough will rotate
through the western states long-wave pattern producing even
stronger winds. Look for southwest winds at 15 to 25 mph gusting
to over 40 mph, especially from about Flagstaff eastward Monday
afternoon. The main concern on Monday will be a heightened fire
weather threat as dry air and gusty winds combine for a
environment more conducive to fire spread. By Tuesday there will
be enough moisture and dynamic lift combined with cooling aloft
associated with the short-wave trough for a slight chance of high
based showers near the Arizona/Utah border. Winds will lighten up
a bit later on Tuesday as the short-wave moves eastward.

From Wednesday onward...A series of short-wave troughs continue
to brush northern Arizona delivering afternoon west to southwest
breezes each day and periodic slight chances for high-based
showers along the Arizona/Utah border.

&&

.AVIATION...Friday 17/12Z through Saturday 18/12Z...Look for VFR
conditions. West to southwest winds generally in 5 to 15 kts
gusting around 20 kts range are forecast during the afternoon.

OUTLOOK...Saturday 18/12Z through Monday 20/12Z...Expect VFR
conditions with southwest winds 10 to 20 knots with gusts to 30
knots each day.

&&

.FIRE WEATHER...Today and Saturday...Dry conditions return. South to
west winds 10-20 mph with afternoon RH values between 10-20%.

Sunday through Tuesday...Warm and dry conditions will continue.
Southwest to west winds 15-25 mph gusting to 30-35 mph Sunday,
increasing to 25-35 mph gusting to 35-45 mph on Monday, then
decreasing on Tuesday. Afternoon RH values will range between 5-15%
each day. Near critical fire weather concerns, especially across
eastern Arizona, on Monday.

&&

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

&&

$$

PUBLIC...Humphreys/McCollum
AVIATION...McCollum
FIRE WEATHER...McCollum

For Northern Arizona weather information visit
weather.gov/flagstaff