Area Forecast Discussion
Issued by NWS Houston/Galveston, TX

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FXUS64 KHGX 281512
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
1012 AM CDT Fri Jul 28 2017

.UPDATE...
Added in some isolated showers and thunderstorms for this
afternoon/evening as PWs seem to be higher today than was
previously expected. The latest GOES-16 PW estimates are coming
in at around 1.8-1.9 inches along and south of the I-10 corridor,
and with those PWs we should be able to squeeze out a handful of
showers/storms. The primary concern with any strong storms that
area able to develop will be gusty winds as the storms collapse,
which is similar to what we`ve been seeing over the past few days.
Otherwise, today will be pretty hot, but sufficient mixing should
keep heat index values below heat advisory criteria (108). 11


&&

.PREV DISCUSSION... /ISSUED 504 AM CDT Fri Jul 28 2017/

DISCUSSION...
Hot & mostly dry wx will persist going into Saturday with upper
ridging remaining in control. Lower PW`s and warmer 850/700mb
temps should keep rain chances quite limited. Can`t completely
rule out a lone cell or two late in the afternoon today, but
coverage should be isolated at best. Heat indicies should generally
remain just below advsy criteria, but the usual outdoor heat precautions
should be taken nonetheless.

Similar conditions are expected Saturday, with temps maybe a
degree or two warmer considering a llvl sw flow in place. (It`s
actually not out of the question that readings approach the record
high of 96 at GLS - set 142 years ago in 1875 - if the seabreeze
is late to arrive).

Late Saturday afternoon and evening a backdoor front should be
moving across La and into east Texas. PW`s of around 2.4" are
forecast to pool ahead of this boundary...so would anticipate at
least some sct precip with its approach. Whether it arrives early
enough into our CWA to tap into daytime instability is questionable.
Some guidance points that way, while others show a later arrival
during the overnight hours and into Sunday morning when there will
be less instability/forcing. Will likely need to adjust pops once
we have a better idea of what timing will look like.

A drier airmass will move in behind the front late Sunday into
early Tuesday. But by midweek, PW`s will nudge back up to 2-2.2"
and the region will eventually become situated in a weakness/trof
axis stretching from the ne states to south Tx, persisting into
the weekend. So a return to a wetter pattern should be in the
works during the second half of next week. 47

MARINE...
Generally light S/SW winds and low seas are expected today. Winds
will be picking up a bit tonight as the gradient tightens in res-
ponse to a front moving in from the NE. This boundary should move
into the northern portions of SE TX late Sat afternoon with winds
over the coastal waters becoming more light/diffuse (given an in-
creasingly weaker pressure gradient) over the weekend. Winds will
then be shifting to the NE Sunday night (through Monday) with the
passage of the front. Isolated/scattered storms are possible with
this system. Winds during the early part of next week will likely
remain from the E as the surface high settles across the Northern
Plains. 41

AVIATION...
Will keep with the general VFR trend this afternoon. TSRA chances
are expected to be low so will likely stay with the current VCSH/
VCTS wording. 41

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)     101  78 102  78  98 /  10  10  20  20  20
Houston (IAH)              98  79  99  78  95 /  20  20  20  30  20
Galveston (GLS)            93  83  94  83  91 /  10  10  10  40  40

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&

$$

Discussion...11



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