Area Forecast Discussion
Issued by NWS Tucson, AZ

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FXUS65 KTWC 241626
AFDTWC

Area Forecast Discussion
National Weather Service Tucson AZ
925 AM MST Mon Jul 24 2017

.SYNOPSIS...Scattered to numerous showers and thunderstorms
remain possible through this evening then conditions for
thunderstorms become less favorable for storms Tuesday through
Thursday. Another upswing in activity will develop late in the week
into the weekend.

&&

.DISCUSSION...All of the heavy rain action this morning has been
occurring across south-central and southwest Arizona plus west
central New Mexico. For our area the shower activity recently moved
out of western Pima county with cloud cover thinning a bit across
the remainder of SE AZ. Atmosphere continues to be really wet with
morning Tucson sounding having a PW value of 1.92", which was
similar to Sunday. A few storms have already developed over the
higher terrain with another active day with scattered showers and
thunderstorms producing localized heavy rain as storms move to
generally to the north. Flash flooding concerns still exist but
won`t be widespread enough to warrant another flash flood watch to
be posted. See previous discussion for remainder of the week.

&&

.AVIATION...Valid thru 25/12Z.
Scattered TSRA/SHRA developing again today and lingering into the
evening before diminishing late this evening. Expect VFR conditions
with multiple cloud layers above 6k ft AGL. Surface wind variable in
direction mainly less than 12 kts, except in the vicinity of TSRA
where gusts may exceed 45 kts. Aviation discussion not updated for
TAF amendments.

&&

.FIRE WEATHER...Expect scattered thunderstorms and showers
this afternoon and evening, a few of which will produce a brief
period of heavy rain and/or strong winds.  Thanks to a bit of drying
fewer storms are forecast Tuesday through Thursday with a lower
threat of heavy rain. Thereafter chances increase once again.
Temperatures will remain below normal today then rebound to near
normal Tuesday through Friday. 20-foot winds will remain below 15
mph with the exception of strong outflow winds in the vicinity of
thunderstorms.

&&

.PREV DISCUSSION...Tuesday through Thursday the atmospheric moisture
drops significantly, basically back down to more normal July levels
and that combined with a less favorable thermal profile aloft will
hinder convection quite a bit and our much lower pops reflect that.
This scenario will also allow temperatures to jump back to normal
Tuesday through Thursday under plenty of sunshine. Thankfully
dewpoints will be 10-15 degrees lower so it won`t feel quite as
humid.

Model trends continue to suggest a decent moisture surge from the
south Thursday night into Friday with a fair amount of moisture
remaining over the area through the weekend.  Therefore would expect
an upswing in convection and a downward tweak to the high
temperatures.  Made a few adjustments to further push the forecast
in that direction.  Cerniglia

&&

.TWC WATCHES/WARNINGS/ADVISORIES...None.

&&

$$

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