629
FXUS65 KPSR 060956
AFDPSR
Area Forecast Discussion
National Weather Service Phoenix AZ
256 AM MST Wed May 6 2026
.KEY MESSAGES...
- A pronounced warming and drying trend will occur over the next
several days as strong high pressure builds over the region,
pushing temperatures to above normal starting Thursday.
- Hot temperatures will develop over the region by the weekend
with lower desert highs topping 100 degrees as early as Friday
before peaking at just over 105 degrees by early next week.
&&
.SHORT TERM /TODAY THROUGH THURSDAY/...
The weather system that brought much cooler air into the region
along with some isolated rainfall is slowing exiting to the
southeast. Drier air has already started to work its way into the
area from the north and this will keep skies clear to mostly clear
at least in the short-term. A high amplitude upper level ridge is
also edging into the Pacific Northwest and much of California.
This feature is forecast to slowly move into our region from the
northwest starting Thursday. The cool air mass currently in place
will begin to modify already today with highs reaching into the
mid to upper 80s, but more so starting Thursday as the high
pressure ridge starts to influence the region. The rapidly rising
heights starting Thursday is expected to push readings to as warm
as the upper 90s across the Lower CO River Valley and southeast
California to 92-95 degrees in the Phoenix area.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
A noticeable shift in the weather pattern late this week and
lasting through at least the first part of next week will lead to
any weather systems tracking across southern Canada into the
North-central and Northeastern U.S. Upper level ridging will also
slowly take over across much of the Western U.S. and eventually
into the Southern Plains by early next week. The first ridge that
will move into our region late this week is expected to weaken
somewhat, but another even stronger ridge is favored to build in
from the west over the weekend and last through at least the first
part of next week. H5 heights are seen rising to between
582-585dm this weekend before likely peaking between 588-591dm
next Monday. Forecast uncertainty increases a bit going into the
middle of next week as there are some discrepancies with a weak
cut-off low that may develop west of Baja. However, for now this
feature may end up being too weak to have much influence over our
region later next week.
Forecast temperatures continue to rise over the weekend into
early next week with highs easily topping 100 degrees by Saturday
and potentially even reaching or topping 105 degrees as early as
Sunday. Widespread Moderate HeatRisk is expected over the weekend
as afternoon temperatures climb to above 100 degrees. The hottest
temperatures should fall on Monday and/or Tuesday with the latest
NBM indicating some western lower deserts reaching 110 degrees to
105-107 degrees in the Phoenix area. This very well could result
in Major HeatRisk across portions of the area for Monday and
Tuesday, so Extreme Heat Watches/Warnings may eventually be
needed. Skies are likely to stay fairly clear through at least
Monday, but some higher clouds may finally make their way into the
region by next Tuesday or Wednesday depending on what happens
with the potential cut-off upper level low. Models do mostly
favor the ridge breaking down during the latter half of next week
likely leading to a cooling trend. Despite this, above normal
temperatures should persist as highs look to stay close to 100
degrees late next week.
&&
.AVIATION...Updated at 0515Z.
South Central Arizona including KPHX, KIWA, KSDL, and KDVT:
No major aviation concerns are expected during the TAF period
under mostly clear skies. Winds will resume their light and
diurnal trends, with a later than usual switch to the E/SE tonight
ahead of a quick return back to W`rly flow by the late morning
hours. Some occasional gusts will be possible during Wednesday
afternoon but should only reach into the mid-teens.
Dependent on smoke generation by the wildfire in Buckeye, W-SW
winds Wednesday afternoon may pull more smoke into central
portions of Phoenix and could impact slantwise visibility,
especially during the afternoon and evening timeframe.
Southeast California/Southwest Arizona including KIPL and KBLH:
No major aviation concerns are expected during the next 24 hours.
Outside of periods of variability, winds should favor a W/SW`rly
component during the forecasting window. Mostly clear skies will
dominate the region through Wednesday evening.
&&
.FIRE WEATHER...
A rapid warming trend over the next several days will push
readings to above normal by Thursday and to well above normal
starting this weekend. Humidities will also quickly lower over the
next couple of days with MinRHs reaching 15-25% today to around
10% starting Thursday. However, despite the drier and warmer
conditions, winds will be fairly light with only periodic upslope
gusts in the mid teens through Thursday. Breeziness should pick
up more Friday into the weekend with gusts to around 20 mph
expected. Although conditions for critical fire weather will not
be met, single digit MinRHs and well above normal temperatures by
this weekend may produce some areas of elevated fire danger.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&
$$
SHORT TERM...Kuhlman
LONG TERM...Kuhlman
AVIATION...RW
FIRE WEATHER...Kuhlman
NWS Phoenix Office
Tucson, AZ 
