000
FXUS65 KPSR 260508
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
1008 PM MST Sat Jan 25 2020

.UPDATE...Updated Aviation Discussion.

&&

.SYNOPSIS...
Slightly above normal temperatures will continue through the
weekend as high pressure predominates across the western states. A
series of weak low pressure systems will move through the Four
Corners next week. However, only light precipitation is expected
across the higher terrain north and east of Phoenix.

&&

.DISCUSSION...
Mesoanalysis this afternoon was showing an upper ridge building into
the western CONUS as dry northwesterly flow aloft promoted mostly
clear skies across the region. Sunday will be similar to today as
mostly clear skies persist and temperatures warm up into the 70s
during the afternoon across the lower deserts. Phoenix is forecast
to hit a high of 73 degrees tomorrow afternoon, which is several
degrees above seasonal normals.

Not much has changed in regards to next week`s forecast narrative. A
couple of disturbances are still set to move through the Desert
Southwest with rain chances remaining minimal across south-central
Arizona. The first shortwave will propagate southeastward into the
state Sunday night into Monday. Virtually all ECMWF EPS and GEFS
Plume members keep any measurable rain to the northeast of our area.
Current PoPs across south-central Arizona remain in the single
digits while slightly higher chances remain over southern Gila
County. Minor breeziness will follow the passage of this wave with
minimal cooling expected.

A second stronger disturbance is forecast to dive down from the
Pacific Northwest into Arizona Wednesday. Forecast PoPs remain in
the single digits across the lower deserts with better rain chances
over southern Gila County. Best chances for any measurable precip
will remain east over the higher terrain though amounts look to
remain low given the dry inland trajectory of this system. The
biggest impact of this system will be the generation of strong gusty
northerly winds over the deserts west of Phoenix with some of the
strongest winds occurring near the lower Colorado River Valley.
Winds may reach advisory levels, but it is too early to say this far
out. Thursday into Friday, amplified ridging builds back into the
Desert Southwest with tranquil weather conditions prevailing. For
the Phoenix area overall, dry conditions are favored to continue
over the next 7 days.

&&

.AVIATION...Updated at 0510Z.

South-Central Arizona including KPHX, KIWA, KSDL, and KDVT...
Southeast California/Southwest Arizona including KIPL and KBLH:

There are no major aviation weather concerns through the TAF
period. Winds will remain light, mostly at or below 7 kts, with
directions favoring diurnal directional tendencies. There will
also be periods of calm/variable winds. High clouds will persist
throughout the forecast period and lower from 25 kft to about 15
kft by Sunday evening.

&&

.FIRE WEATHER...
Saturday through Wednesday: Temperatures will warm to above seasonal
normal levels during the period with warmer deserts generally low to
middle 70s each day. Conditions will be mostly dry with minimum
humidity values dropping into the 20-30% range across the lower
desert and 30-40% range for the higher terrain. It will be slightly
drier next Tuesday and Wednesday as desert humidity levels fall into
the upper teens in many areas. Winds will remain fairly light
although the Lower Colorado River Valley may see some gusts up to 20
mph Thursday and Friday. There are indications that another weather
system could bring a slight chance for rain early next week mainly
over high terrain areas to the east of Phoenix.

&&

.SPOTTER INFORMATION STATEMENT...
Spotters should follow standard reporting procedures.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&

$$

DISCUSSION...Smith/CB
AVIATION...Hodges/Deems
FIRE WEATHER...Deems/CB

NWS PSR Office Area Forecast Discussion