FXUS65 KTWC 202152

Area Forecast Discussion
National Weather Service Tucson AZ
252 PM MST Fri Oct 20 2017

.SYNOPSIS...A passing system will bring breezy conditions today and
cooler temperatures Saturday and Saturday night. After another
possibly cooler night Sunday, a strong high pressure system will
push temperatures rapidly back up, with near record high
temperatures expected the first half of next week.


.DISCUSSION...The trough passing through the region is deep enough
to bring breezy conditions to our area this afternoon, but not
much else as precip and the main storm track remain well north of
our area.

Cooler air behind the frontal passage Saturday, with temperatures
actually dropping back to near or below average Saturday afternoon
and Saturday night. Much cooler morning lows Sunday, with middle
30s to middle 40s in coldest eastern valleys to upper 40s and 50s
from Tucson westward. Lower dew points Sunday night into Monday
morning may facilitate even cooler temperatures in colder eastern
Valleys, with a few locations near freezing possible in Sulphur
Springs Valley and other cold prone locations. We're currently
expecting dew points to drop into the 20s and upper teens. If they
crater into the lower teens and single digits we may actually end
up needing a freeze warning for portions of Cochise County.

A world beater ridge building in from the eastern Pacific will
push our temperatures to record levels the first half of next
week, including middle to upper 90s for Tucson International
Airport. Please see the climate section below for additional


.AVIATION...Valid thru 22/00Z.
Patchy cirrus at times. SFC wind SWLY/WLY at 12-20 kts with gusts
near 30 kts by 20/18Z. SFC wind decreasing to less than 12 kts
aft 21/03Z. Aviation discussion not updated for TAF amendments.


.FIRE WEATHER...Dry conditions will prevail through most of next
week. Breezy southwest to west winds today into Saturday,
followed by occasionally gusty east winds early next week. Clear
skies and light winds developing Saturday night and Sunday.


.CLIMATE...90 degree days at Tucson International Airport continue
to mount, with the 180th day of 90+ degree high temperatures
today. We continue to put distance between 2017 and the old record
of 178 days which occurred in 1910 and 1989. After a break
Saturday, more to come next week.

After the break over the weekend, record or near record high
temperatures are likely early next week as an unseasonably strong
ridge of high pressure aloft builds over the area. Current
forecast high of 97 for Tucson Intl next Tuesday would be the
second latest occurrence of 97 in the calendar on record. The
record latest date is Oct 27 2016. There is also a small chance
next Tuesday that the high at Tucson Intl could hit 98, which, if
that happens, would be the latest occurrence of 98 in the calendar
on record, besting the current latest date of Oct 19 in 1921 &

Tucson International Airport
Forecast Record
Mon Oct 23 96 94
Tue Oct 24 97 96
Wed Oct 25 94 95






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