Area Forecast Discussion
Issued by NWS Phoenix, AZ
FXUS65 KPSR 272157
Area Forecast Discussion
National Weather Service Phoenix AZ
300 PM MST Thu Apr 27 2017
Deepening low pressure system is expected over the Four Corners area
Friday, and will bring windy conditions across Arizona Friday
afternoon and evening, including high fire danger. There is also a
chance of afternoon showers and thunderstorms over the mountains
east of Phoenix. Mostly clear skies and cooler temperatures are
forecast this weekend, with a significant warming trend next week.
Tonight through Friday Night...
Dry northwest flow aloft replete with variable high clouds are
forecast tonight and early Friday, ahead of another strong cold
front forecast to sweep south through Arizona Friday afternoon and
evening. Strong atmospheric height falls over central AZ Friday
afternoon, with cold air packing along/behind the front portend
strong gusty winds. This upcoming wind episode may be slightly
stronger than Tuesdays wind event, and peaking between 6 pm and 9 pm
on the deserts and mountains surrounding the Phoenix area.
A Red Flag Warning for high fire danger is posted for a large
portion of central and southern AZ Friday afternoon and evening.
Additionally, there is a chance of afternoon showers and
thunderstorms over the mountains of southern Gila County just east
of Phoenix Friday afternoon.
Clearing skies with diminishing wind are expected Friday night.
Saturday and Saturday night...
Saturday will be the coolest day after Fridays frontal passage.
Breezy to windy conditions are also forecast, but not as strong as
those expected by Friday evening. The windiest areas Saturday
afternoon will occur down the Colorado River Valley.
Sunday through Thursday
Dry northwest flow aloft, along with warmer temperatures are
forecast this period. Strong warming will occur next Wednesday and
Thursday with high temperatures approaching the 100 degree mark.
South-Central Arizona Including KPHX, KIWA, and KSDL: Occasionally
gusty west winds and timing a couple wind shifts will be the main
aviation concern through Friday morning with only high cirrus cigs
20K ft and above. Late this afternoon into the evening, west wind
gusts around 25 mph will be common before weaker winds set in beyond
mid evening. The typical overnight switch to an easterly heading
will occur much later than usual towards 12Z and only persist a
Friday afternoon outlook: Very gusty west winds with occasional
speeds as high as 35 mph will be likely Friday afternoon potentially
affecting arrival and departure rates.
Southeast California/Southwest Arizona Including KIPL and KBLH:
Periods of strong gusty winds and a couple distinct wind shifts will
be the primary aviation problems through Friday morning under only
higher cirrus cigs. A northerly component this afternoon will become
westerly this evening with some time of variable direction possible
overnight. A frontal passage will cause winds to switch back to
northerly Friday morning with very strong gusts beginning during the
late morning hours.
Aviation discussion not updated for amended TAFs.
Sunday through Thursday: Strong high pressure will build across the
districts next week resulting in a steady warming trend, dry
conditions, and weaker wind speeds than experienced this week.
Minimum afternoon humidity values will fall to near 10 percent over
most of the area while high temperatures rise into a range of 5-10
degrees above average. Overnight recovery will only be poor to fair.
Afternoon and early evening winds will favor a west to northwest
direction with the typical late April/early May upslope gustiness.
Winds overnight will mostly trend towards a drainage direction.
.SPOTTER INFORMATION STATEMENT...
Spotter activation will not be needed through the middle of next
AZ...Red Flag Warning from 11 AM to 9 PM MST Friday for AZZ132.
Red Flag Warning from 3 PM to 9 PM MST Friday for AZZ133.
Red Flag Warning from 9 AM to 4 PM MST Friday for AZZ131.
Wind Advisory from 2 PM to 8 PM MST Friday for AZZ552-557-
CA...Red Flag Warning from 9 AM to 4 PM PDT Friday for CAZ231.
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