148
FXUS65 KFGZ 061750
AFDFGZ

Area Forecast Discussion
National Weather Service Flagstaff AZ
1050 AM MST Thu Jun 6 2024

.SYNOPSIS...Hot temperatures will continue through the end of the
week, with daily chances for showers/thunderstorms across the
higher terrain through the weekend. Afternoon highs will gradually
cool Saturday and Sunday, before another warming trend returns
next week.

&&

.UPDATE...Not much to update this morning as things are quiet
across the region. Temperatures have already started warming
quickly this morning with much of the region well into the 80s
already. It will be a hot one out there today so be sure to stay
cool and hydrated, especially if you are spending time outdoors.

PW on this morning`s sounding was 0.41", which falls right into
the median range for this time of year. A few high clouds can be
seen starting to work their way to the north- northwest as
moisture starts to make its way between the high pressure to the
east and low pressure to the southwest. This will not translate
into much of anything but there should be just enough lift and
instability to allow for a few isolated thunderstorms to develop
along the higher terrain. With the heat in place, we will likely
see more evaporation occurring with storms so there is a chance
that we may end up with mostly dry thunderstorms and not much
precipitation reaching the ground.

Overall, the forecast is in good shape. Only edit was to up the
PoPs across the Grand Canyon to indicate isolated showers/storms
this afternoon.

&&

.PREV DISCUSSION /423 AM MST/...By no surprise, the Flagstaff
Airport hit a record temperature yesterday of 89 degrees, with the
previous record being 88 degrees set back in 2010. These
hot/potentially record breaking temperatures will continue through
the end of the week. As a result, an Excessive Heat Warning
begins this morning (10 AM MST) and continues through Friday
evening (8 PM MST). Areas included in this warning: Grand Canyon,
Marble/Glen Canyons, and the valleys of Yavapai County all below
4000`.

Although high-pressure is dominating the upper-levels of the
atmosphere across the West U.S., there is a low-pressure system
sitting off the southern California Baja coast. As the high begins
to shift eastward over the next few days, this low will help
create a south-southeast flow into Arizona. This pattern will
bring just enough moisture to our CWA to have slight chances for
showers/thunderstorms across the higher terrain today, and
becoming more focused over eastern Arizona Friday through Sunday.
With the anticipated daytime heating, and current lack of moisture
at the surface, storms that do build over the next few afternoons
will likely be on the drier side. This will leave the main threats
from storm development to be dry lightning and gusty winds.

As the high-pressure slowly weakens/progresses eastward over the
weekend, temperatures will slightly cool 5-10 degrees from the
afternoon highs forecast for Thursday and Friday. At the start of
next week, temperatures will once again climb 2-10 degrees above
normal. There will also be a none-zero chance of showers/storms
across eastern Arizona through mid-week, but overall, mostly dry
conditions look to return.

&&

.AVIATION...Thursday 06/18Z through Friday 07/18Z...VFR outside of
ISOLD high-based -SHRA/-TSRA. TS are most likely to develop and
impact localized areas from 20Z-02Z with erratic, gusty winds from
downbursts. Be wary of areas near virga below high-based storms.
S-SW surface winds at 5-15kts, gusting near 20 kts will become
light, variable after 02Z.

OUTLOOK...Friday 07/18Z through Sunday 09/18Z...VFR conditions
are expected with ongoing afternoon (18Z-02Z) ISOLD high-based
SHRA/TSRA, primarily for eastern Arizona. Winds increase the next
few days out of the SW at 10-20 kts, gusting near 25kts from
17Z-02Z. Otherwise, light and variable.

&&

.FIRE WEATHER...Thursday and Friday...Daytime temperatures continue
to run 5 to 10 degrees above normal. Isolated, high-based convection
is possible today over much of the area, with the focus shifting
east on Friday. A very dry boundary layer means wetting rain is
unlikely. The main threats will be dry lightning and gusty winds.
Afternoon RH values remain below 15 percent. Winds generally light
and southerly today, from 5 to 15 mph. Winds increase and turn
southwesterly Friday, ranging from 10 to 20 mph, with gusts to 25
mph.

Saturday through Monday...Temperatures retreat to just a few degrees
above normal. Isolated, high-based convection remains possible each
day over the eastern zones, but conditions are dry. Afternoon RH
values from 10 to 20 percent each day, along with afternoon
southwest winds 10 to 20 mph.

&&

.FGZ WATCHES/WARNINGS/ADVISORIES...
Excessive Heat Warning until 8 PM MST /9 PM MDT/ Friday for
AZZ005-006-037.

&&

$$

PUBLIC...Meola/Konieczny
AVIATION...Mazon
FIRE WEATHER...Peterson

For Northern Arizona weather information visit
weather.gov/flagstaff