Special Weather Statement, NWS Brownsville, TX

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
1238 AM CDT Sat Oct 16 2021

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

&&

.AVIATION...Frontal boundary approaching the regional airports
with observations at the 3 air terminals currently void of all
convection and cloud cover. VFR conditions prevail at 06Z,
however some lower clouds and potential development of convection
is possible until a few hours after the frontal passage. TAFs
still advertise some MVFR cigs and some rain showers between 09Z-
12Z with some showers in the vicinity until 15Z...after this VFR
prevails with decreasing cloudiness. North winds increase post
frontal with gusts 25-30 knots through the morning and early
afternoon with strongest winds along the Lower Texas coast.

&&

.PREV DISCUSSION... /issued 638 PM CDT Fri Oct 15 2021/

DISCUSSION...Updated for latest aviation discussion below.

AVIATION...VFR conditions will continue into early evening across
all aerodromes. A cold front will move through the area overnight
tonight into Saturday morning. Ahead of the front showers and
thunderstorms will be possible across all aerodromes reducing
visibilities to MVFR late tonight to around daybreak Saturday.
Winds will increase behind the front with gusty northerly winds of
20 to 25 kts and sky conditions will improve with VFR conditions
returning.

PREV DISCUSSION... /issued 255 PM CDT Fri Oct 15 2021/

SHORT TERM (Now through Saturday Night): Tonight is the night
that the cold front comes through Deep South Texas! Models are in
good agreement for the timing of the front to move through around 06-
12z Saturday, however, the CWA will see some isolated showers and
thunderstorms before the front this Friday evening. The HRRR has a
few clusters of thunderstorms moving into the northern Ranchlands
around 22z Friday and moving south down the center of the CWA
towards Hidalgo county by 02-03z Saturday.

Right behind those storms, we can expect the front to make its way
to Deep South Texas by midnight and exit the area by Saturday
morning leaving us with a dry, cool air mass. Winds will become
northerly and quite breezy with gusts up to 20 kts due to the FROPA.
Models have shown these northerly winds to increase rapidly
especially over the Gulf Waters/Coastal County areas. A Wind
Advisory has been issued for the coastal counties of Kenedy,
Willacy, and Cameron as well as a Gale Warning for the Gulf Waters.
Both are issued for 03-15z Saturday.

Dewpoints will begin to fall to 40-50 degrees by 12z Saturday
morning making for a pleasant autumn-like Saturday with mostly
cloudy skies and high temperatures in the upper 70s to lower 80s. We
will also see a cooler than average Saturday evening as northerly
winds die down and temperatures drop to the mid 50s and 60s for the
CWA.

LONG TERM (Sunday through Friday): High pressure will be in full
control on Sunday maintaining a cool and subsident airmass over
the Rio Grande Valley. Temperatures will continue to be well below
normal on Sunday with northerly winds in place. High pressure then
will shift eastward late Sunday into Monday, allowing for easterly
and southeasterly moisture return flow to set back in. This will
favor a gradual warming trend through the early portions of the
coming week. A series of weak midlevel waves and disturbances will
then begin to approach the region starting on Wednesday. These
midlevel features may combine with increasing moisture at lower
and midlevels to introduce rain chances back into the forecast
from Wednesday through Friday. Confidence in exact timing and
magnitude of rainfall remains low given the relatively weak and
diffuse nature of the midlevel features.

MARINE (Now through Saturday Night): Light to moderate onshore
flow will continue until the cold front passes through overnight
tonight. Winds can be expected to change to northerly by around 06z
with rapid intensification with gusts up to 35 kts. Seas will begin
to build by early Saturday morning reaching 8 to 9 feet with
occasional seas up to 10 feet by tomorrow afternoon. As mentioned in
the discussion above, a Gale Warning has been issued for the Gulf
Waters from 03-15z Saturday. Winds and seas start to subside by
Saturday evening. As seas come down, Small Craft Advisory may still
be needed through the rest of the period after the Gale Warning
expires.

Sunday through Wednesday: Low-end SCEC criteria may be ongoing
early Sunday morning in the wake of Saturday’s cold front. Winds
and seas will gradually improve on Sunday as high pressure builds
into the area. Light to moderate winds and seas are then
anticipated for much of the period. Chances for showers and
thunderstorms then look to return on Wednesday as moisture at
lower and middle levels increases.

&&

.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL  63  79  65  82 /   0   0   0   0
BROWNSVILLE          61  81  64  84 /   0  10   0   0
HARLINGEN            58  80  61  84 /   0   0   0   0
MCALLEN              57  80  60  85 /   0   0   0   0
RIO GRANDE CITY      56  81  57  86 /   0   0   0   0
SOUTH PADRE ISLAND   71  77  71  79 /   0  10   0   0

&&

.BRO WATCHES/WARNINGS/ADVISORIES...
TX...Wind Advisory until 10 AM CDT this morning for TXZ256-257-351.

GM...Gale Warning until 10 AM CDT this morning for GMZ130-132-135-150-
     155-170-175.

&&

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

59-GB/99

Hazardous Weather Outlook
National Weather Service Brownsville TX
420 PM CDT Fri Oct 15 2021

TXZ248>255-353-162130-
Zapata-Jim Hogg-Brooks-Inland Kenedy-Starr-Southern Hidalgo-
Inland Willacy-Inland Cameron-Northern Hidalgo-
420 PM CDT Fri Oct 15 2021

This Hazardous Weather Outlook is for portions of Deep South
Texas.

.DAY ONE...Tonight

A few thunderstorms tonight along a cold front will be capable of
producing gusty winds and brief heavy rainfall.

Strong northeast winds will develop behind a cold front late this
evening and overnight. A Wind Advisory is in effect for Coastal
Kenedy, Willacy, and Cameron Counties from 10 PM tonight to 10 AM
Saturday.

There is a moderate risk of rip currents at area beaches, becoming
a high risk after midnight.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

Strong northeast winds will develop behind a cold front late this
evening and overnight. A Wind Advisory is in effect for Coastal
Kenedy, Willacy, and Cameron Counties from 10 PM tonight to 10 AM
Saturday.

There is an elevated risk of rip currents at beaches along the
lower Texas coast Saturday and Sunday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

GMZ130-132-135-150-155-170-175-TXZ256-257-351-162130-
Laguna Madre from the Port of Brownsville to the Arroyo Colorado-
Laguna Madre from the Arroyo Colorado To 5 NM north of Port
Mansfield TX-
Laguna Madre from 5 nm north of Port Mansfield to Baffin Bay TX-
Coastal waters from Port Mansfield to the Rio Grande out 20 nm-
Coastal waters from Baffin Bay to Port Mansfield out 20 nm-
Waters from Port Mansfield to the Rio Grande extending from 20 to
60 nm-
Waters from Baffin Bay to Port Mansfield extending from 20 to
60 nm-Coastal Willacy-Coastal Cameron-Coastal Kenedy-
420 PM CDT Fri Oct 15 2021

This Hazardous Weather Outlook is for portions of Deep South
Texas, The Gulf of Mexico, and The Laguna Madre.

.DAY ONE...Tonight

Strong north winds with gusts to gale force will be possible late
tonight behind a cold front. A Gale Warning is in effect for
the Laguna Madre and Gulf waters out to 60 nm from 10 PM tonight
to 10 AM Saturday.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

Strong north winds with gusts to gale force will be possible late
tonight into Saturday morning behind a cold front. A Gale Warning
is in effect for the Laguna Madre and Gulf waters out to 60 nm
from 10 PM tonight to 10 AM Saturday. Small Craft Advisories may
be needed on Saturday and Saturday night for portions of the Gulf
waters due to lingering high seas.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

Special Weather Statement
National Weather Service Brownsville TX
230 AM CDT Sat Oct 16 2021

TXZ253>257-160815-
Coastal Willacy TX-Inland Willacy TX-Southern Hidalgo TX-
Coastal Cameron TX-Inland Cameron TX-
230 AM CDT Sat Oct 16 2021

...Thunderstorms along a cold front will impact portions of
southeastern Hidalgo, Cameron and southeastern Willacy Counties
through 315 AM CDT...

At 229 AM CDT, Doppler radar was tracking a strong thunderstorm over
San Benito moving south at 15 mph.

HAZARD...Winds in excess of 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Harlingen, Weslaco, San Benito, Donna, Mercedes, La Feria, Los
Fresnos, Progreso, Santa Rosa and Rancho Viejo.

This includes the following highways...
 Interstate Highway 69 E between mile markers 1 and 36.
 US Highway 281 between mile markers 792 and 838.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 2595 9715 2584 9743 2603 9766 2609 9827
      2654 9727 2640 9745 2645 9737 2639 9741
      2639 9740 2640 9740 2653 9728 2636 9738
      2646 9724 2636 9733 2644 9723 2636 9731
      2641 9722
TIME...MOT...LOC 0729Z 347DEG 14KT 2613 9761

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

Hallman