570
FXUS65 KTWC 152037
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
137 PM MST Sat Jun 15 2024

.SYNOPSIS...Hot weekend with an Excessive Heat warning in effect
for portions of southeastern Arizona. Temperatures decrease a bit
early next week before likely heating up again by Thursday.
Moisture may begin to increase late next week which would bring
the potential for high-based thunderstorms.

&&

.DISCUSSION...Sunny skies with temperatures running a few degrees
warmer than yesterday as of 12pm today. Water Vapor imagery shows
a trough moving into the Pacific Northwest with high pressure
building slightly to our east. Temperatures in the lower valleys
will experience hotter temperatures this afternoon and tomorrow.
Excessive Heat Warning is in effect for the lower elevations in
Pima, Pinal, Graham, and Greenlee Counties for the weekend.

By Monday, the trough will move inland and passing to the north
which will bring some breezy conditions in the afternoon. This
will also elevated fire weather concerns, please see Fire Weather
Discussion for further details.

The middle of the week, temperatures will hover near to slightly
above normal with some afternoon breezes. The synoptic pattern
will have lingering troughiness over the region to keep
temperature in check. The high pressure will build to the east
and increasing the thickness levels substantially. This means,
hotter temperatures coming across the Southeast Arizona with the
Heat Risk in the Major Risk Category. Right now, Tucson has a 25%
of hitting 115 degrees on Thursday. That is a degree shy of
hitting the June 20th record temperature of 116F in 2017!

Moisture will also be moving into the region starting Thursday
afternoon. The placement of the High Pressure will aid in the
moisture advection into the region. At first, the storms will be
mainly high based and dry for Thursday and Friday. By the
weekend, more moisture will be in placed for better chances and
more coverage of showers and thunderstorms across Southeast
Arizona. Promising signs for the monsoon.

&&

.AVIATION...Valid through 17/00Z.
Clear skies/SKC conditions thru the forecast period. SFC wind SWLY
through NWLY at 8-13 kts thru 16/03Z, then SFC wind less than 10 kts
and variable in direction til 16/18Z. Aft 16/18Z, SFC wind SWLY/WLY
at 11-16 kts and gusts to 18-25 kts thru the end of the forecast
period. Aviation discussion not updated for TAF amendments.

&&

.FIRE WEATHER...Hot and dry conditions will continue through the
weekend, with a few degrees of cooling early next week. High
temperatures will then heat back up late next week, with the hottest
temperatures of 2024 possible on Thursday and Friday. Through the
middle of next week, expect min RH values of 4-9 percent in the
lower elevations and 8-15 percent in the mountains, along with
overnight recoveries between 25-40 percent in most locations. RH
values then increase 5-10 percent the latter half of next week. 20-
foot winds will follow typical diurnal patterns, with afternoon and
early evening gustiness due to strong surface heating. Sustained 20-
foot wind speeds will be 15 mph or less through Sunday. Winds then
increase on Monday, with southwest winds of 15-20 mph and gusts to
30-35 mph. A few areas will be near critical fire weather thresholds
Monday, especially to the east/southeast of Tucson, but at this time
we not expecting it to be widespread enough for a watch or warning.
Elevated afternoon/early evening winds of 15-20 mph then continue
for much of next week. By the end of next week, the models show an
increase in mid-level moisture, resulting in a slight chance mainly
dry thunderstorms to the east of Tucson Thursday and Friday and as
far west as Tucson next Saturday.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...
Excessive Heat Warning until 8 PM MST Sunday for AZZ504>506-509.

Excessive Heat Warning until 8 PM MST this evening for AZZ501-
502.

&&

$$

Public...Strongman
Aviation...Zell
Fire Weather....Zell

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