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000
FXUS64 KHGX 270253
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
953 PM CDT Fri May 26 2017

.UPDATE...
Only a few minor tweaks were made to the previous forecast to
account for current obs. Otherwise, the previous forecast appears
to be on track.  11

&&

.PREV DISCUSSION... /ISSUED 615 PM CDT Fri May 26 2017/

AVIATION...
Look for MVFR ceilings to develop this evening and persist overnight
with south winds around 10 knots. Ceilings will lift tomorrow morning,
but not expecting VFR levels to be reached areawide until the late
morning through early afternoon hours. South winds will increase during
the day with gusts >20 knots at some spots. Lowering cloud decks will
then develop after sunset and persist until Sunday morning. Sunday`s
south winds will be weaker than what the area will be seeing on Saturday.
Look for increasing shower and thunderstorm coverage as we head on
into Sunday night and Monday morning.  42

PREV DISCUSSION... /ISSUED 409 PM CDT Fri May 26 2017/

DISCUSSION...
Despite the extensive afternoon cloud cover many regional temperatures
have again reached the lower 90s. Higher humidities/dew point temperatures
have equated to upper 90 F heat indices at this hour. Winds remaining
around 5-10 mph and skies becoming overcast through the overnight
hours signals there is a good chance that there may be some high minimum
temperature records that will be threatened...many are forecast to
fall to within a degree or two of high minT records in the upper 70s
to 80 F along the coast. Upper ridging planted across region
pretty much guarantees that the majority of this holiday weekend
will be dry...very low rain chances albeit mostly cloudy very warm
and muggy with 98 F - 105 F heat indices during the mid to late
afternoon. Ridging begins to break down late Sunday and this will
mark the beginning of a very unsettled weather pattern that may
persist through a good portion of next week.

NWP suite continues to forecast periods of showers and thunderstorms
from late Sunday through Thursday. A series of shortwave trough passages
early in the week will be the trigger for Memorial Day convection.
A slow moving frontal boundary will reach the CWA Monday morning...
providing better lower level focus within a greater than 1.7 inch
pwat air mass for storm clusters to move upon. The main threat on
Memorial Day will be localized heavy rainfall that will produce
flooding. As of now the best focus and higher moisture will reside
along and south of I-10...thus slightly higher convective chances
will be over the southern third of the forecast area from Memorial
Day through mid week. Upper level forcing may be there on Monday
as eastern Texas may fall under a RRQ of a Ohio Valley-centered
jet. A developing coastal surface trough with a possible movement
of a warm frontal boundary (or a hybrid-looking system per the
GEM) will increase the potential for more early week southern
county tornadic activity. Inverted V soundings on Tuesday and
Wednesday also support damaging storm winds. Other than tornadic
activity...the other marginal threat will be hail as more saturated
warm columns/relatively high wet-bulb zero heights do not lean
towards a significant hail threat. Quite frankly...the pattern
going into early June looks very muddled. All progs maintain QPF
in their mass fields with no mentionable driver (e..g, s/w
passage, ll boundary) so the term `unsettled` seems to best fit
this Memorial Day. As if usually the case...any Memorial Day
action will determining Tuesday-Friday`s forecast as it will
likely be all meso-driven past Monday anyway. 31

MARINE...
Moderate onshore winds will persist through Saturday night and a
SCEC will remain in effect for the offshore waters tonight. A weak
cold front will move into SE TX late Sunday night and stall near the
coast early Monday. WInds will begin to relax in advance of this
feature Sunday. The frontal boundary gets diffuse and will likely be
driven by mesoscale rain events Monday possibly pushing an outflow
into nearshore waters Monday or Monday night. Showers and thunderstorm
chances will increase Sunday and Monday across the coastal waters.
Mariners should prepare for possibly some strong storms on Monday
with brief gusty winds. Onshore winds return Tuesday and will
remain onshore through the end of the week.

There are several other beach hazards to remain alert for this
holiday weekend. The strong onshore winds has produced elevated
tides and some minor flooding at high tide will be possible along
the Bolivar peninsula. The strong onshore winds will also foster
strong rip currents. If heading to the beaches, swim near life
guards and stay away from jetties and piers. 43

&&

.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL)      76  94  76  90  70 /  10  10  20  30  60
Houston (IAH)              78  93  78  90  74 /  10  10  10  30  70
Galveston (GLS)            80  87  80  85  76 /  10  10  10  20  70

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION until 9 AM CDT Saturday for
     the following zones: Waters from Freeport to the Matagorda
     Ship Channel from 20 to 60 NM...Waters from High Island to
     Freeport from 20 to 60 NM.

&&

$$

Discussion...11