Area Forecast Discussion
Issued by NWS Brownsville, TX

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43
000
FXUS64 KBRO 111939
AFDBRO

Area Forecast Discussion
National Weather Service Brownsville TX
239 PM CDT Fri Aug 11 2017

.SHORT TERM (Now through Saturday night): Moisture remains
persistent across the region this afternoon, as noted by PW values
this morning still at 2 inches and current GOES PW imagery. Main
issue today with any convection is a small pocket of dry air at
midlevel and east winds aloft shearing the seabreeze apart.
Showers will remain isolated along the immediate coast the rest of
the day before dissipating with loss of heating. GOES imagery
does show the swath of drier air just offshore starting to rotate
into the region. Once this arrives tonight, drawn in by the
southward shifting H% ridge, convection will have an exceedingly
difficult time breaking through the cap. With this in mind, went
ahead and pulled rain chances from the forecast for tonight
through tomorrow night. With the strengthening of the midlevel
ridge, compressional heating will be on the upswing starting
tomorrow. This pushes highs into the upper 90s and low 100s, with
heat index readings 108 to 111 Saturday afternoon.

.LONG TERM (Sunday through Friday): A 593 decameter high will be
parked over south Texas Sunday, with 1014 mb high pressure over
the Gulf. This pattern will persist quite well through the long
term. Though can`t rule out a stray afternoon or coastal shower,
rain chances will be muted in the long term, and for now have gone
with a dry long term forecast. Seasonal weather will continue
from the short into Sunday and thereafter, with light to moderate
onshore (southeast) winds and a mix of clouds and sun each day.
Temperatures will be a few degrees above normal on avg., with heat
index values typically in the 103 to 108 degree range for much of
the area for a few hours each afternoon.

&&

.MARINE:
Now through Saturday night: Swells have settled around the 4 foot
height today, but the main difference is the reduction of the long
wave period, which fell from 10 seconds last night to 7 seconds
now. Both wave action and period will continue to decrease as
Gulf waters stabilize after Franklin. High pressure will shift to
the northern Gulf, keeping the gradient relaxed, with resulting
onshore flow 10 knots or less through the first half of the
weekend.

Sunday through Wednesday: Mid level ridging overhead and surface
high pressure over the Gulf will support moderate to fresh
southeast to south winds and moderate seas. Diurnal effects will
promote small craft should exercise caution conditions on the
Laguna during the day, with similar conditions off and on during
both day and night on the Gulf waters.

&&

.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL  79  94  80  94 /   0   0  10  10
BROWNSVILLE          78  95  79  95 /   0   0   0  10
HARLINGEN            78  98  78  98 /   0   0   0  10
MCALLEN              80 101  79 100 /   0   0   0   0
RIO GRANDE CITY      78 102  78 103 /   0   0   0   0
SOUTH PADRE ISLAND   82  88  82  90 /   0   0  10  10

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...High Rip Current Risk until 6 PM CDT this evening for TXZ251-256-
     257.

GM...None.
&&

$$

This product is also available on the web at:
HTTP://WEATHER.GOV/RGV

64/54



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.