251 
FXUS64 KBRO 070909
AFDBRO

Area Forecast Discussion
National Weather Service Brownsville TX
309 AM CST Sun Nov 7 2021

.SHORT TERM (Today through Monday): 500mb ridge across east Texas 
and northern Mexico will continue to provide subsidence across south 
Texas today through Monday. At the surface...a weak onshore flow 
will continue across the lower Texas coast today through Monday with 
surface high pressure across east Texas and Louisiana shifting 
slowly eastward through the short term forecast period. Below normal 
to near normal temperatures will prevail today through Monday. No 
rain chances are expected. Patchy fog will develop across portions 
of the CWA late tonight into early Mon morning.

Tides were running just below minor flood category along the lower 
Texas coast last night and with high tide tonight at 8:20 pm...will 
likely see water levels approach minor flood category so will issue 
a coastal flood statement for minor tidal overflow for this
evening.

.LONG TERM (Monday Night through Saturday):H5 ridge begins to
flatten Monday night ahead of a shortwave forecast to move 
through northern Texas Tuesday. Not a whole lot of fanfare 
expected with this shortwave as it only helps to increase mid to 
high level cloudiness Tuesday night into Wednesday. A longwave 
trough begins moving into the High Plains Wednesday afternoon and 
will push a cold front into northern Texas Wednesday night. A 
secondary vort max on the backside of the longwave trough causes 
it to dig farther south Thursday night into Friday and will help 
push the cold front through Deep South Texas sometime Friday. Rain
chances remain highest over the Gulf waters as the cold front 
pushes south, but the 0Z EURO did show slightly better rain 
chances across Deep South Texas, so this trend will continue to be
monitored in future forecasts. 

As far as temperatures are concerned, a southeast to southerly
breeze  will continue to cause both overnight and daytime temps 
to moderate through Thursday afternoon. Friday’s temperatures 
are highly dependent on the timing of the cold front, so continued
with the NBM for temperatures Thursday night into Friday. As the 
cold front clears by Friday afternoon, cooler, drier weather moves
in thanks to a surface high oozing down from the Central Plains. 
As a result, decided to trend a bit cooler than the NBM and mixed 
it with the NBM 25 percent for lows, especially in the Northern 
Ranchlands, Friday night and Saturday night. Below normal daytime 
highs are anticipated Friday and Saturday.

Dew points and relative humidity values are forecast to drop quite
a bit behind the cold front Friday. Will continue to monitor any
trends for fire weather concerns due to the possibility of areas
west of I-69C having RH values less than 25 percent Friday and/or
Saturday afternoons.

&&

.MARINE (Today through Monday): Seas were near 4 feet with east to 
southeast winds near 4 knots at buoy020 at 2:10 am this morning. 
Light east winds will prevail across the coastal waters today with 
surface high pressure across the northwest Gulf coast. The pressure 
gradient will remain weak across the lower Texas coast tonight into 
Monday. Light southeast winds will prevail across the coastal waters 
tonight into Monday.

Monday night through Friday: Light to moderate southeast to south
winds and low to moderate seas prevail through Wednesday morning.
Winds pick up Wednesday afternoon, and could reach SCEC criteria,
due to a developing low in the middle of the country and a
tightening pressure gradient over our coastal waters. After a
brief relaxation of the winds Thursday afternoon into Thursday
night, they’ll begin to pick up to near SCA criteria Friday
morning as the cold front nears and clears the lower Texas coast
Friday afternoon. The cold front will also bring a chance for
scattered showers and storms to our coastal waters Thursday night
through Friday afternoon. 

&&

.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL  78  64  81  64 /   0   0   0   0 
BROWNSVILLE          81  63  83  65 /   0   0   0   0 
HARLINGEN            79  59  82  62 /   0   0   0   0 
MCALLEN              82  59  84  63 /   0   0   0   0 
RIO GRANDE CITY      82  58  85  61 /   0   0   0   0 
SOUTH PADRE ISLAND   76  72  78  73 /   0   0   0   0 

&&

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

$$

This product is also available on the web at:
https://weather.gov/rgv

Short Term...61-Castillo
Long Term...58-Reese