000
FXUS64 KBRO 161748
AFDBRO

Area Forecast Discussion
National Weather Service Brownsville TX
1248 PM CDT Wed Aug 16 2017

.DISCUSSION...Updated for latest aviation discussion below.

&&

.AVIATION...
MVFR ceilings have cleared and lifted with VFR prevailing at all
TAF sites. Rest of the period should be quiet outside of a very
isolated streamer shower. Chances for MVFR are low tomorrow
morning and did not mention anything in the TAFs.

&&

.PREV DISCUSSION... /issued 610 AM CDT Wed Aug 16 2017/

DISCUSSION...Updated for latest aviation discussion below.

AVIATION...Satellite images and surface observations indicate a
few low clouds across portions of the CWA this morning. Ceilings
were near 1600ft at KT65 to near 3500ft at KMFE. Expect VFR
conditions to prevail across the Rio Grande valley and northern
ranchlands today as the 500mb subtropical ridge across the
southeast United States and the Gulf of Mexico continues to
provide subsidence across the area.

PREV DISCUSSION... /issued 415 AM CDT Wed Aug 16 2017/
SHORT TERM (Today through Thursday): 500mb subtropical ridge
across the southeast United States and the northern Gulf of Mexico
will provide subsidence across the western Gulf of Mexico and
south Texas today as a 500mb shortwave trough moves across the
central plains this afternoon. Surface low pressure across the
southern plains and surface high pressure across the eastern Gulf
of Mexico will provide a strong pressure gradient across the lower
Texas coast today. This will provide breezy conditions across the
CWA today through tonight. Low to mid level moisture will remain
limited across the area today through Thursday even as an onshore
flow continues to bring moisture at the surface. Will go with
persistence for temperatures today through Thursday as the upper
level ridge across the southeast U.S. and northern Gulf of Mexico
continues to dominate the weather pattern. Heat index values may
reach 108 to 112 degrees across the coastal sections for an hour
or two this afternoon so will issue an SPS for elevated heat index
temperatures across the coastal counties.

LONG TERM (Thursday Night through Tuesday): Although 500 mb high
pressure, centered anywhere between south Georgia and north Texas,
will dominate over Deep South Texas and the Rio Grande Valley
through the forecast period, opportunities for precipitation over
most of the Lower Texas coastal waters, and/or along and east of
the Interstate 69E corridor, will periodically present themselves
due to the approach and passage of weak inverted 500 mb troughs
through the BRO CWFA. Well above normal temperatures will persist
due to relatively limited cloud cover and precipitation chances.

MARINE (Today through Thursday): Seas were near 6 feet with south
to southeast winds near 19 knots at buoy020 early this morning.
Moderate to strong south to southeast winds will prevail across the
coastal waters today as surface low pressure across the southern
plains and surface high pressure across the eastern Gulf of Mexico
provides a strong pressure gradient across the lower Texas coast.
Will word SCEC for the Laguna Madre and offshore waters today but
may need to issue a small craft advisory for the bay waters. The
pressure gradient will remain strong across the western Gulf of
Mexico tonight before weakening on Thursday. Small craft advisories
may be needed for the offshore waters tonight.

Thursday Night through Tuesday: Surface high pressure over the
Gulf of Mexico will ease westward as thermal low pressure over
north-central Mexico does the same. This will result in light to
moderate winds and low to moderate seas for the Lower Texas
coastal waters through the forecast period. Small Craft Exercise
Caution and Small Craft Advisory are not likely to be needed.

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...Small Craft Advisory until 9 PM CDT this evening for GMZ135.

&&

$$

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