FXUS65 KPSR 201815

Area Forecast Discussion
National Weather Service Phoenix AZ
1115 AM MST Thu Jun 20 2019

.UPDATE...Updated Aviation Discussion.


A weak weather disturbance slowly passing by to our north through
Saturday will bring breezy conditions and a slight cool down into
the weekend. This will result in below normal temperatures and
highs mostly in the upper 90s to around 100 degrees this weekend.
High pressure will slowly build across the region next week
leading to temperatures warming back to around normal readings
while dry conditions prevail.


The overall quiet weather conditions look to continue well into
next week with elevated fire danger being the only forecast
concern. Current analysis shows weak flow aloft, but this will
change later today as a deep trough sags southward through the
Pacific Northwest. This trough will increase winds aloft enough
later today to lead to widespread afternoon breezy conditions to
locally windy across southeast California. Temperatures today will
be nearly identical to the last couple days, but as the trough
drifts closer to our region Friday into Saturday, highs will bottom
out in the upper 90s on Saturday. Daytime breezy to locally windy
conditions will last through Saturday with winds being slightly
higher Friday. Fire weather conditions will be the main concern
through Saturday due to the winds and continued low RHs.

The trough is forecast to eventually shift to the east on Sunday
leaving mostly dry zonal flow over our region through Monday.
Another deep Pacific trough will set up across the Northwest U.S.
by next Tuesday and Wednesday, turning our flow out of the
southwest and likely leading to another round of breezy
conditions. Heights aloft do gradually creep upward next week,
pushing temperatures back to around normal readings during the
latter half of next week. Though models have backed off some on
bringing a strong subtropical high into our region late next week
into the following weekend, it still looks possible highs will
approach 110 degrees across the southern Arizona deserts. There
are also signs sufficient moisture may seep into far eastern
Arizona for some shower or thunderstorm activity beginning late
next week.


.AVIATION...Updated at 1814 UTC.

South-Central Arizona including KPHX, KIWA, KSDL, and KDVT;

Southerly crosswinds this morning will remain below 10 kts before
transitioning to a westerly component this afternoon. Periodic
gusts up to 20 kts will be possible into the afternoon, tapering
off this evening. Otherwise, SKC conditions prevail through the
TAF period as dry westerly flow aloft persists.

Southeast California/Southwest Arizona including KIPL and KBLH:

Breezy to windy conditions are expected this afternoon into the
evening with gusts reaching up to 25-30 kts at the terminals. At
KIPL, southerly winds this morning will give way to a westerly
component while KBLH maintains a S/SW component. Gusts taper off
later tonight with sustained speeds falling to around 10 kts.
Otherwise, SKC conditions prevail through the period as dry
westerly flow aloft dominates.

Aviation Discussion not updated for amended TAFs.


Saturday through Wednesday:
Cooler temperatures through this weekend will eventually give way
to a steady warmup to near seasonal temperatures next week.
Daytime humidity values will still remain near 10% each afternoon
with overnight recovery into the 20-30% range. Gusty winds will
remain a concern through Sunday, especially across the Tonto NF
and Rim area, with gusts upwards of 20 mph before calming
slightly through the week.


Spotter activation is not expected.


CA...Wind Advisory from 4 PM this afternoon to 2 AM PDT Saturday for

     Wind Advisory from 4 PM this afternoon to 11 PM PDT this evening
     for CAZ560.




NWS PSR Office Area Forecast Discussion