FXUS65 KTWC 182146
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
246 PM MST Mon May 18 2026

.SYNOPSIS...A storm system tracking to our north across the Great 
Basin will result in breezy conditions and below normal high 
temperatures across southeast Arizona today. High temperatures warm 
to near normal by Wednesday and remain there into next weekend.

&&

.DISCUSSION...So far today breezy to locally windy conditions have 
been observed across southeast Arizona under hazy skies. Sustained 
winds of 10-20 mph with occasional gusts to 25-30 mph have been 
measured with locally higher gusts along the New Mexico border in 
Cochise County. Windy conditions over the past few days has 
contributed toward the hazy skies. Breeziness will continue this 
afternoon resulting in near critical fire weather conditions for 
areas mainly south and east of Tucson. More details in the fire 
weather section below. Overall, today has the feel of another one of 
those windy Sonoran Desert days where trash cans and patio furniture 
might not want to stay upright with the sky looking a bit hazy from 
being all stirred up. Afternoon breezes will begin to taper shortly 
after sunset but return again tomorrow through Wednesday afternoon 
for areas mainly south and east of Tucson. Wind speeds are forecast 
to be lighter compared to the last few days, so little to no impacts 
are expected. As for temperatures, this afternoon highs will top out 
in the mid to upper 80s or about 5 to 10 degrees below normal.
Wednesday, we will see temperatures warm back up closer to normal 
(upper 80s to low 90s) which will continue into the weekend.

By this weekend into early next week, ensembles are trying to 
introduce rather modest mid-level moisture (between 0.5-0.8 inches 
of precipitable water) in conjunction with a upper low. If this 
pattern occurs it may bring increased breeziness, nonzero chances 
for precipitation, and temperatures trending near normal late this 
week into early next week. Given how dry it has been and how dry it 
usually is this time of year, my hunch is that it will be tough to 
see much in the way of measurable precipitation from this system 
without gradual moistening of the atmosphere from the top-down. With 
that in mind, I would expect predominantly virga and cloud buildups 
from this system if it comes to fruition with perhaps a low end
chance (10-15%) for an isolated dry thunderstorm. The NBM 
currently advertises a slight chance (10-20%) for precipitation 
focused over the terrain mainly south and east of Tucson and in 
the White Mountains from Saturday through early next week. That 
being said, unless there is more evidence that moisture will 
indeed get wrapped up into the system, my confidence for 
widespread precipitation chances remains on the low end. 
Something to keep an eye on ahead of the weekend.

&&

.AVIATION...Valid through 20/00Z.
Mostly SKC-FEW thru the valid pd with ocnl thin high level cirrus 
AOA 20k ft AGL. SFC winds WLY/SWLY at 11-19 kts with gusts between 
25-30 kts. Highest winds expected south/east of KTUS in the vicinity 
of KDUG thru 19/03Z. Thereafter, SFC winds primarily terrain driven 
at less than 8 kts until picking and becoming WLY/SWLY again after 
19/17Z with speeds of 9-17 kts and ocnl gusts to 22-26 kts.

&&

.FIRE WEATHER...Breezy to locally windy conditions (sustained winds 
15-20 mph; gusts between 30-35 mph) combined with low relative 
humidity (as low as 13 to 18 percent) and dry fuels this afternoon 
will result in near critical fire weather conditions across eastern 
portions of Cochise County. Winds will taper off after sunset and RH 
will recover to between 40 and 50 percent overnight. Tomorrow and 
Wednesday, elevated fire weather conditions are forecast (especially 
for southeast portions of Cochise County) as breezy conditions 
(winds around 15 mph; gusts 25-30 mph) and minimum RH (between 10 to 
15 percent) continue thru Friday afternoon. While confidence remains 
low, there is a slight chance (10-20%) for cloud buildups and virga 
over the weekend into early next week in the White Mountains and 
terrain over to the south and east of Tucson. Stay tuned.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...None.

&&

$$

DVS

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