Flagstaff, Arizona 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

615
FXUS65 KFGZ 010513
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
1013 PM MST Sat May 31 2025

.SYNOPSIS...By Sunday, subtropical moisture will move into the area
and will bring widespread shower and thunderstorm activity, along
with cooler weather through at least the middle of next week.

&&

.UPDATE...Some virga remains across northern Arizona this evening,
but this activity should continue to decrease through the rest of
the evening hours. Current forecast is on track with no updates
needed this evening.

&&

.PREV DISCUSSION /432 PM MST/...Moisture increasing in the mid-
levels has brought a few showers and even some lightning strikes
today, but wetting the ground has been a struggle. Moisture
increases will become more noticeable tonight, as the boundary
layer surge begins from the south.

This is because a large closed low west of the central Baja coast
will continue to entrain sub-tropical moisture, forcing it northward
through the Gulf of California the remainder of today into Sunday.
As this low opens up and moves into Arizona Sunday afternoon into
Monday, instability associated with the cooler mid-levels around the
low will overlap with PW values near seasonal maxima over portions
of Arizona. An area of modest lift also forms east of northeast of
the ejecting low early Sunday afternoon through Monday morning,
mainly over central and eastern Arizona. All this will combine for
areas of showers and thunderstorms in our CWA, with some more
organized storms producing locally heavy rainfall amounts.

As this first low ejects Monday afternoon, less organized convection
will continue in the moist air mass left behind, even as another low
forms off the southern California coast. This second low will move
into Arizona Tuesday and Wednesday, for more shower and thunderstorm
activity. Depending on how intact the second low stays, Wednesday
could feature additional organized and dynamically driven storms, we
will keep an eye on that.

Temperatures will fall to well below normal readings after today
and during this unsettled period. Winds should not be impactful.

Finally, drier and somewhat warmer for later in the week, although
the longer wave trough keeps lingering to the north, so confidence
is not great.

&&

.AVIATION...Sunday 01/06Z through Monday 02/06Z...Mainly VFR
conditions expected. SCT SHRA/TSRA increasing in coverage from
south to north after 18Z. Heavier showers may produce MVFR or
lower conditions. Gusty winds in excess of 30 kts possible near
showers. Otherwise, light winds generally less than 15 kts.

OUTLOOK...Monday 02/06Z through Wednesday 04/06Z...Mainly VFR
conditions expected with increasing coverage of SHRA/TSRA from
through Monday. Expect SHRA/TSRA to become more isolated Monday
night into Tuesday. Heavier showers may produce MVFR or lower
conditions and gusty winds. Otherwise, light winds generally less
than 15 kts.

&&

.FIRE WEATHER...Sunday and Monday...Moisture increases Sunday, with
showers and thunderstorms developing in the afternoon, lasting into
Monday. Expect a good chance of wetting rain with erratic and gusty
winds near any showers/storms. The moisture increase comes with
lower high temperatures as well, with minimum relative humidity
values generally above 15 percent. Daytime winds ranging from south
to southwest at 5 to 15 mph through the period.

Tuesday through Thursday...Moisture will remain in place with
scattered showers and thunderstorms continuing for Tuesday and
Wednesday. Activity will become more isolated by Thursday. Look for
southwest winds at 10 to 20 mph with gusts to 30 mph on Tuesday,
turning lighter on Wednesday and Thursday.

&&

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

&&

$$

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

For Northern Arizona weather information visit
weather.gov/flagstaff