Area Forecast Discussion
Issued by NWS Tucson, AZ
FXUS65 KTWC 252135
Area Forecast Discussion
National Weather Service Tucson AZ
235 PM MST Sat Mar 25 2017
.SYNOPSIS...Dry conditions, mild temperatures and gusty winds
at times during the afternoon through Monday. A weather disturbance
will then make its way into the region for a a cool-down in
temperatures and a chance of light showers Tuesday and Wednesday.
After a brief warm-up the second half of the upcoming week, another
storm system will then make its way into the region late Friday and
.DISCUSSION...The upper pattern is defined by a closed upper low
over MO, a trough moving through the Great Basin, and a longwave
ridge of high pressure in the Eastern Pacific. Southeast Arizona
resides on the southern periphery of the trough, with a the latest
satellite imagery indicating the wedge of high clouds have since
moved east into New Mexico.
The main impact of this system will be breezy conditions, especially
to the southeast of Tucson. These winds, in combination with the dry
airmass already in place will result in very localized and brief
critical fire weather conditions late this afternoon. This is a very
borderline situation, so we currently do not have a Red Flag Warning
Otherwise, Southeast Arizona will be impacted by a few weather
systems over the next week. The first system will move through
northern Arizona Tuesday and Wednesday, bringing with it a chance of
light valley rain to our forecast area, and even a few inches of
mountain snow to higher elevations of the White Mountains. The
majority of the GEFS member plumes for QPF indicate this system will
generally bring less than a tenth inch of rain to Tucson, with
slightly higher amounts farther NE (less than a quarter inch in
The second system will move into the area Friday into Saturday.
Still some differences between the GFS and ECMWF on the strength and
duration of this feature. The 25/12Z GFS is much more bullish with
this system, and the 25/12Z ECMWF run, which had been more
progressive, has now come more in line with the GFS solution. This
system is stronger and colder than the first system. the main impact
will be strong gusty winds Friday along with a chance of showers
Friday and Saturday.
.AVIATION...Valid through 26/23Z.
Clear skies/SKC conditions most locations with just a FEW clouds at
8-12k ft AGL north of a KTUS to KSAD line thru 26/12Z. Aft 26/12Z,
FEW-SCT clouds AOA 20k ft AGL. Surface wind WLY/NWLY at 10-18 kts
and gusts to 18-25 kts thru 26/02Z, with the strongest wind
east/southeast of KTUS. Surface wind less than 12 kts between 26/02Z
and 26/19Z. Aft 26/19Z, surface wind WLY/NWLY at 8-16 kts, with the
strongest wind again east/southeast of KTUS. Aviation discussion not
updated for TAF amendments.
.FIRE WEATHER...A series of weather systems will bring windy
conditions at times over the next 7 days. The strongest winds are
expected through early this evening, Monday and Tuesday afternoons
and then next Friday.
Otherwise, expect dry conditions through Monday night, followed by a
chance of showers mainly north and east of Tucson periodically from
Tuesday through next Saturday.
Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson