Area Forecast Discussion
Issued by NWS Tucson, AZ

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

FXUS65 KTWC 120415

Area Forecast Discussion
National Weather Service Tucson AZ
915 PM MST Wed Oct 11 2017

.SYNOPSIS...Most of the region will experience dry weather
that persists into the week ahead, with above normal daytime


.DISCUSSION...Upper air data depicts a 500mb trough axis over the
Pacific Northwest and an elongated high spanning across the southern
states. This pattern is directing dry southwesterly flow across our
area, although a hint of low-level moisture did advect up along the
western flank of the ridge. Precipitable water amounted to 0.82" in
the 12/00Z sounding and surface dew points have increased 5-10
degrees from 24 hours ago.

Scattered fair weather cumulus was about all we could muster this
afternoon and that cloud field has been slowly dissipating since
sunset. Temperatures reached well above normal in all areas and
Tucson was only one degree shy of the nation`s high temperature of
98 in Phoenix.

The quiet forecast remains in good shape this evening. Skies will
continue to clear and light terrain driven winds hold through the
night. Please see the previous discussion for additional details.


.AVIATION...Valid thru 13/06Z.
FEW clouds at 8k-12k ft AGL east of KTUS will gradually dissipate to
SKC later this evening, returning Thursday afternoon. Terrain driven
SFC wind less than 10 kts remains through tonight, picking up SWLY
Thursday afternoon 10-14 kts with gusts to 20 kts possible. Aviation
discussion not updated for TAF amendments.


.FIRE WEATHER...Dry conditions persist across a vast majority
of the region, with above normal daytime temperatures into early
next week. There`s a slight chance of a stray thunderstorm or two
developing Friday afternoon and perhaps again early next week across
the higher terrain in southeast Cochise County. The strongest winds
occur Thursday afternoon when southwest gusts reach 20 to 25 mph,
becoming typical diurnal flow mainly less than 15 mph into next


.PREV DISCUSSION /205 PM MST/...Dry west to southwesterly flow aloft
is prevalent today across southeast Arizona under mostly sunny
skies. Just enough moisture for a few cumulus clouds south and east
of Tucson. As expected, the breezy easterly winds have diminished
this afternoon with just a few periodic gusts.

The larger scale flow pattern into this weekend consists of
troughiness across the northwest and strong ridging across the
southeast with our forecast area between these systems with
southwesterly flow. Moisture won`t be too far away across Chihuahua,
west Texas and and southern New Mexico but our area should generally
remain dry with some cumulus build-ups in the higher terrain near
the New Mexico border and in Cochise County especially on Friday.
Stronger ridging aloft with higher heights will build across Sonora
and extend into Arizona Sunday into early next week with elevated
height and thickness values. The moisture we`ve been watching mainly
to our south and east early next week doesn`t look very promising
with only a very slight chance of a shower or thunderstorm Tuesday
into Wednesday once again in the higher terrain near the NM border.
Otherwise, the main story heading into next week will be continued
above normal temperatures with highs about 4 to 9 degrees above






Visit us on Facebook...Twitter...YouTube...and at is the U.S. government's official web portal to all federal, state and local government web resources and services.