Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 06/11/20

Area Forecast Discussion

National Weather Service Phoenix AZ

 512 PM MST Wed Jun 10 2020

.UPDATE...Updated Aviation Discussion.

&&

.SYNOPSIS...
A strong warming trend over the next couple days will push
temperatures to above normal starting Thursday with lower desert
highs topping out just shy of 110 degrees on Friday. The hot and
dry conditions will persist into the weekend, but some slight
cooling will drop temperatures closer to normal readings. Breezy
conditions are also anticipated over the weekend. The cooling
trend will be brief as above normal temperatures will return for
the first half of next week.

&&

.DISCUSSION...
Very dry westerly flow remains in place across the Desert
Southwest under completely clear skies. At the time of this
discussion there are no clouds present in the state of Arizona.
This lack of clouds reflects the very dry airmass in place, with
precipitable water values currently at a paltry 0.26 inches as
revealed by aircraft soundings. The warming trend will continue
today into Thursday as upper level heights continue to rise before
peaking early Friday. Highs today will top out right around
normal, which is 103 degrees for Phoenix. Guidance shows 500mb
heights peaking between 592-594dm on Friday which is around the
98th percentile of the NAEFS climatology for the date. Forecast
highs of 107-109 on Thursday and Friday fall just short of high
heat risk. Into Friday afternoon, heights aloft will begin falling
from west to east in response to an approaching Pacific trough,
but surface cooling will be minimal. High temperatures on
Saturday and Sunday will fall 1-3 degrees most areas, with 3-5
degrees of cooling across southeast California. The approaching
trough will also lead to an increase in winds on Friday and
especially Saturday with widespread afternoon gusts of 20-30 mph.
The very low daytime RHs and breeziness on Friday will lead to
elevated fire weather conditions. By Sunday, winds will begin to
relax with more typical afternoon breezes of 10-15 mph.

The near normal temperatures will most likely be brief as the
ridge to our south again builds back into the region during the
first half of next week. For now it looks like core of the ridge
will stay to our south or southeast, so highs will most likely
stay below 110 degrees early next week with very dry air
continuing to advect into the region from southwesterly flow.
Another potential trough will approach from the northwest later
next week but will likely follow a similar track to the last few
leaving our area under warm southwest flow. The closest any rain
chances come over the next week looks to be near the Arizona/New
Mexico state line this weekend.

&&

.AVIATION...Updated at 0005Z.

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

Minimal aviation weather concerns are anticipated through the TAF
period. Mostly light to occasionally light and variable winds
will favor normal diurnal trends. With Thursday afternoon`s
westerly wind, some occasional wind gusts of 15-20 kt are possible
in the late afternoon and early evening. Otherwise, skies will
remain clear to mostly clear through the period.

Southeast California/Southwest Arizona including KIPL and KBLH:

Minimal aviation weather concerns through the TAF period. Winds will
remain light, mainly aob 8 kts. At KIPL light and variable winds
will become westerly by around 05Z. There is also a slight chance
of slightly reduced visibilities in haze or smoke during the
period but the probability was too low to include in the TAF. At
KBLH winds will be light and variable or light and westerly
through late Thursday morning. Winds will pick up from the south
on Thursday afternoon with some gusts near 20 kt from mid to late
afternoon. Skies will remain clear through the period.

&&

.FIRE WEATHER...
Saturday through Wednesday:
A modest cooling trend of 1-3 degrees from Friday into Saturday is
anticipated, with high temperatures near normal Saturday and
Sunday. Winds will increase on Saturday with gusts of 20-30 mph.
Although the winds will not be as intense as was seen with the
last system, there will still be elevated fire weather concerns.
Winds decrease slightly Sunday into Monday. Expect single digit
Min RH values at most places through early next week. Max RH
values will be around 20-30% for most locations while climbing to
around 35-45% for eastern parts of southern Gila County as
moisture increases mainly across eastern parts of the state later
this week.

&&

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

&&

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

$$

DISCUSSION...Hodges/Kuhlman
AVIATION...Sawtelle
FIRE WEATHER...Hodges/Kuhlman