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000
FXUS64 KBRO 222336
AFDBRO

Area Forecast Discussion
National Weather Service Brownsville TX
636 PM CDT Mon Apr 22 2024

...New AVIATION...

.SHORT TERM...
(Tonight through Tuesday night)
Issued at 140 PM CDT Mon Apr 22 2024

Forcing associated with an upper level shortwave and slightly
unstable overrunning low-level flow have allowed for the development
of elevated showers and thunderstorms today. Rain chances decrease
from west to east late this afternoon as the upper level shortwave
and the associated forcing move out of the area.

Through the remainder of the period, a strengthening upper-level
ridge centered along the front range of the Rocky Mountains will
provide persistent northwesterly flow aloft which will aid in drying
the mid-levels. The combination of reduced forcing and dryer mid
level flow will keep rain chances near zero for the remainder of the
period.  At the surface, northerly winds shift easterly this evening
and southeasterly later tonight. This wind shift will bring warmer
air to the region, allowing high temperatures to reach the low to
mid 80s Tuesday afternoon and low temperatures in the upper 60s to
low 70s Tuesday night.

&&

.LONG TERM...
(Wednesday through next Monday)
Issued at 140 PM CDT Mon Apr 22 2024

A rather typical Spring synoptic weather pattern is anticipated
across the CWA through the extended forecast period. Initially a
strong mid/upper ridge axis will remain in control from Mexico
into the Central Plains on Wed and Thu. A series of moderate to
strong shortwaves moving from the Pacific into the Plains will
push this ridge axis east of our CWA by Fri. This will leave us in
a broad southwesterly flow aloft from Fri into early next week. A
series of surface low pressure systems will maintain breezy to
windy south to southeast flow through the weekend. The windiest
day would appear to be Fri as the 925 mb LLJ approaches 40-45 kt.
DESI further confirms the potential for a Wind Advisory for the
Lower Valley on Fri with a 40-50% probability. Sat will again be
windy but probably just shy of Wind Advisory levels.

An approaching Pacific cold front on Mon is expected to stall
well to our north given the much weaker push of the southern
extent of this frontal boundary. As a result, most of the NWP
guidance keeps our CWA dry on Mon. However the 12Z ECMWF solution
does prog the potential for convection with a closer approaching
frontal boundary. For now, will keep the CWA dry for Mon but later
shifts will need to monitor the movement of this frontal boundary
and any MCS potential, especially given the time of year. Will
also maintain a dry forecast for the remainder of the forecast
given a building cap, limited moisture, and little to no forcing
that will persist through most of the extended forecast period.

As for temps, will depict a warming trend in line with the blended
guidance given the persistent warm to hot south/southeast flow.
By Fri, most inland high temperatures will reach the 90s with this
trend continuing through the remainder of the forecast period.

&&

.AVIATION...
(00Z TAFS)
Issued at 636 PM CDT Mon Apr 22 2024

Outside of a small area of showers tracking east south of the Rio
Grande, rain-free conditions are expected through the TAF period.
Satellite imagery depicts overcast skies across the region, with
most sites reporting VFR ceilings at the time of this writing.
HREF probabilistic guidance indicates intermittent periods of MVFR
ceilings may return between 08-14Z, but probabilities are low
(~30%). There is a higher chance of MVFR ceilings beginning
around 16-17Z and continuing through the end of the TAF period at
all TAF sites. Otherwise, winds will continue to gradually shift
to the east tonight and southeast tomorrow.

&&

.MARINE...
Issued at 140 PM CDT Mon Apr 22 2024

Now through Tuesday night...High pressure moving into the Northern
Gulf and Southeastern US will support a southeasterly wind shift
tonight, with light to moderate southeasterly winds continuing
through the short term period. With pressure gradients weakening and
wind speeds decreasing this afternoon, seas are expected to become
more moderate tonight, and remain slight to moderate through Tuesday
night. A passing upper level shortwave is supporting a cluster of
showers and thunderstorms currently moving through the area. As
the upper level disturbance shifts further east tonight, rain
chances are expected to decrease and remain near-zero through the
remainder of the short term period.

Wednesday through Monday...South to southeast flow across the
Lower Texas coastal waters will slowly strengthen through Fri and
Sat given the reasons mentioned above. The seas will respond
accordingly and build through the weekend to 7-9 feet. As a
result, small craft advisories will persist between Thu and Sun
for most of the coastal waters given the moderate to strong south
to southeast flow and building seas. An approaching frontal
boundary by Mon will diminish the overall onshore flow and slowly
subside the seas. A capped airmass with limited moisture and
forcing will keep the waters mainly dry through most of the
period.

&&

.PRELIMINARY POINT TEMPS/POPS...
BROWNSVILLE             63  82  73  85 /  20  10   0  10
HARLINGEN               63  84  70  87 /  10  10   0  10
MCALLEN                 64  84  72  89 /  10  10   0  10
RIO GRANDE CITY         62  83  70  89 /  10  10   0  10
SOUTH PADRE ISLAND      69  77  74  78 /  20  10   0  10
BAYVIEW/PORT ISABEL     65  81  71  83 /  20  10   0  10

&&

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

$$

SHORT TERM...60
LONG TERM....80
AVIATION...22-Garcia