Area Forecast Discussion
Issued by NWS Brownsville, TX

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FXUS64 KBRO 131702 AAB
AFDBRO

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
1102 AM CST Mon Nov 13 2017

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

&&

.AVIATION...Challenging TAFs today with periods of MVFR ceilings
and reduced visibility embedded in bands of showers moving east to
west from offshore into the interior of the CWA. Short term
models suggest that this will continue through the afternoon,
especially for the mid valley, before conditions settle down this
evening. Despite the ending of showers this evening, ceilings
could still be problematic. Guidance shows ceilings hovering right
around MVFR height tonight, with visibility also decreasing late
tonight in patchy fog. Winds will be light east northeast before
veering more to southeast Tuesday afternoon.

&&

.PREV DISCUSSION... /issued 536 AM CST Mon Nov 13 2017/

DISCUSSION...Updated for latest aviation discussion below.

AVIATION...Brownsville radar continues to indicate some lingering
light SHRA near MFE and a line of SHRA approaching HRL/BRO from the
east. Satellite images and surface observations indicate a mix of
low level cloud decks and patchy fog across deep south Texas this
morning. Ceilings and visibilities will gradually improve around
mid morning as the low clouds and fog lift and burn off with
diurnal heating. Will continue to mention MVFR tempo groups due to
reductions in ceilings/visibilities in SHRA. Surface high pressure
across the northern Gulf of Mexico will support east to northeast
winds today and tonight. Some patchy fog and low ceilings may
redevelop overnight but should not drop below MVFR levels.

PREV DISCUSSION... /issued 432 AM CST Mon Nov 13 2017/

SHORT TERM (Now through Tuesday): Mid level ridging will remain in
place over northwest Mexico and deep south Texas through the period.
Surface high pressure centered over western Illinois early this
morning will push south across the northern Gulf of Mexico today.
This will allow winds to back to east or northeast through the short
term. Above normal temperatures are expected through the period.
High temperatures today and Tuesday will be in the 80s under a mix
of sun and clouds. Low temperatures tonight will be in the 60s
inland to the lower 70s along the coast.

Brownsville radar continues to indicate an area of scattered showers
moving nortwest across the western portions of deep south texas.
Will keep the mention of higher rain chances across the west this
morning due to ongoing activity. Rain chances continue across the
area today as models indicate some convection developing later this
morning into the afternoon. Will lean towards the latest NAM/HRRR
with additionally activity developing and moving west in the east to
northeast flow. Rain chances end tonight as the deepest moisture is
pushed south of the area along with some drying in the mid levels.
The combination of moist soils from recent rainfall, mostly clear
skies and light winds should allow patchy fog to develop across
portions of deep south Texas Tuesday morning. Some model guidance
suggest that dense fog may develop late tonight, but will mention
patchy fog for now.

LONG TERM (Tuesday Night through Sunday): The main event in the
long term portion of the forecast remains the passage of a cold
front through Deep South Texas and the Rio Grande Valley between
sunrise and noon on Saturday. Isolated showers are possible during
the daylight hours of Saturday in association with the front.
Additionally, the passage of the front will serve to bring daytime
high and overnight low temperatures to more near normal levels in
its wake. Ahead to the cold front, a persistent onshore flow will
produce above normal temperatures, with isolated precipitation
over the eastern and/or central portions of the BRO CWFA Wednesday
night through Thursday night. Some model guidance also hints at
fog, possibly dense, Tuesday night and Wednesday night. Will
monitor model trends before including this in the official
forecast.

MARINE (Now through Tuesday): Buoy 42045 (TGLO TABS Buoy K)
reported southeast winds around 12 knots gusting to around 14
knots at 02 CST/08 UTC. Surface high pressure across the northern
Gulf of Mexico will maintain light to moderate northeast to east
winds and moderate seas through the Tuesday. Small craft should
exercise caution on the offshore Gulf waters tonight and Tuesday
as seas build to 4 to 6 feet.

Tuesday Night through Sunday: The most adverse marine conditions
during the period will occur on Saturday and Sunday, with Small
Craft Advisory possible along the Lower Texas Coast, due to the
early Saturday morning passage of a cold front. Until this period,
generally moderate winds and seas are anticipated in advance of
the cold front with high pressure over the northern Gulf of Mexico
interacting with low pressure over the southern Gulf of Mexico.

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...None.
GM...None.
&&

$$

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