434 
FXUS65 KTWC 082151
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
251 PM MST Fri Oct 8 2021

.SYNOPSIS...Dry and cooler weather is on tap this weekend, cooling
further by the middle of next week as a weather system transits
the region. Winds also increase next week, with a chance of 
showers across portions of southeast Arizona.


&&

.DISCUSSION...High-level cloud cover is streaming across the state
of Arizona this afternoon ahead of an amplified trough over the
western US. No precip is on tap for southeast Arizona as this
system progresses east to west across the region through the
weekend. Winds increase subtly as the gradient tightens, with 
some afternoon breezes on Saturday.

However, this is just an appetizer for what's to come next week. A
robust and unseasonably cold upper low will dive down the
Intermountain West and be centered near the Four Corners region
sometime on Tuesday. Winds are likely to be rather strong from a
climatological perspective Monday into Tuesday. Even more
staggering are the forecast temperatures. Lows dip into the 80th-90th
percentile below normal per the ECMWF EFI guidance. The high
temperature for Tucson on Tuesday is 70 degrees, which is quite
incredible for this time of year. Showers also develop as the 
system swings through, with the best chances in the early hours
Tuesday, drying out by the evening. Temperatures gradually recover
thereafter as more zonal flow sets up, allowing winds to also
slacken.

&&

.AVIATION...Expect SCT-BKN clouds AOA 25k ft MSL through much of today then 
becoming SKC or a FEW clouds AOA 25k ft this evening onward. SFC
winds WLY 7-12 kts with gusts to 20 kts during the afternoon 
hours, becoming light and variable this evening. Aviation not 
updated for TAF amendments.

&&

.FIRE WEATHER...Dry weather is expected through the weekend with 
periods of passing high clouds and afternoon breezes. Surface wind
speeds will remain between 10-15 mph with intermittent gusts to 
around 20 mph each afternoon, favoring the west to southwest. 
Stronger winds along with much colder temps and a slight chance 
for rain are expected early next week as a stronger, colder 
weather system moves in. 20-ft winds will be southwesterly near 
15-25 mph both Monday and especially Tuesday with higher gusts. RH
values will remain above critical thresholds. 

&&

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

$$

Public...Howlett
Aviation...Howlett
Fire Weather....Howlett

Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson