Area Forecast Discussion
Issued by NWS Tucson, AZ
FXUS65 KTWC 270411
Area Forecast Discussion
National Weather Service Tucson AZ
911 PM MST TUE JUL 26 2016
.SYNOPSIS...Adequate moisture will provide scattered mainly afternoon
and evening thunderstorms into this weekend. Perhaps some decrease
in coverage will occur around Thursday. Expect hotter than average
daytime temperatures through Thursday followed by moderating
temperatures by early next week.
.DISCUSSION...Strong organized outflows helped push storms into
more valley locations this afternoon and evening. We had a nice
MCC over south central Pima county with smaller clusters in
eastern Pima county. Coverage was less organized across the rest
of the area, but we have benefited from 3 generations of outflows
triggering additional storm development in areas that were hit
earlier. The increasing easterly flow will help keep a few storms
around overnight. Watching for converging boundaries to
potentially create dust issues along I-10 between Marana and
Picacho Peak until around 10 PM MST.
Residual debris across the area will probably slow heating in the
morning with subsequently later developing storms With the flow
picking up from the east and northeast, we may be setting
ourselves up for a classic rim shot from the White Mountains late
Wednesday afternoon into Wednesday evening.
.AVIATION...VALID THRU 28/06Z.
Scattered thunderstorms will continue through the late
evening...before diminishing in the early morning hours. Storms
will redevelop Wednesday afternoon. Brief wind gusts to 45 kts and
MVFR conditions are possible with the stronger TSRA. Otherwise,
sfc wind mainly less than 10 kts. Aviation discussion not updated
for TAF amendments.
.FIRE WEATHER...Scattered afternoon and evening thunderstorms will
continue the next few days. Wednesday through Friday storms that
develop over the White mountains will move SW off the higher
terrain and over the valley and storms that develop further south
will move mostly to the west. Afternoon temperatures will remain a
bit warmer than average.
.PREV DISCUSSION...Pretty quiet afternoon so far across SE AZ
with isolated storms, as of 210 pm, occurring over/near the
Chiricahua, Santa Rita and White Mountains. Storm activity this
evening mainly over the eastern mountains. A little bit of an
increase in the steering flow will allow a few storms to move into
the valleys with outflow interactions developing additional valley
storms. Outflows from Sonoran evening storms possibly getting as
far north as the border areas for a slight chance of overnight
Steering flow Wednesday and Thursday mainly out of the ENE with
upper high centered over far NW AZ. Thus expect a better chance to
see storms moving off the higher terrain into the valleys.
Thereafter will maintain slight chance to chance type pops for the
weekend into early next week.
Blowing Dust Advisory until 10 PM MST this evening for AZZ504-
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