Severe Thunderstorm Warning 40, NWS Brownsville, TX

Area Forecast Discussion...UPDATED
National Weather Service Brownsville TX
635 PM CDT Thu Aug 11 2022

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

&&

.AVIATION...VFR conditions are anticipated to last through the
night and into Friday morning at all aerodromes. There is a thunderstorm
west of KEBG that is drifting southwest and is expected to pass
west of KMFE, but it will be close, so have included VCTS through
02Z and will continue to monitor the storm.

As for Friday afternoon, ample moisture coupled with
an upper level disturbance nearby will increase shower and
thunderstorm chances and coverage across Deep South Texas.
Confidence is higher in the afternoon, where PROB30s have been
included at all aerodromes. Reduced visibility, ceilings bordering
on MVFR and gusty winds are all possible in and around any storms
that develop Friday afternoon. Confidence wasn't quite there to
include any rain or storms Friday morning, but it may be
necessary in future TAF packages.

&&

.PREV DISCUSSION... /issued 249 PM CDT Thu Aug 11 2022/

SHORT TERM (Today through Friday Night): To start the period
midlevel high pressure continues to be centered over portions of the
High Plains. A mid level inverted trough/low will make its way
westward over the northern Gulf allowing deep moisture to filter
into the area and increasing rain chances through the period.

While much of the CWA will remain dry through this afternoon, the
seabreeze may spark a few showers and thunderstorms mainly along and
east of I-69C, and remain isolated. Shower and thunderstorms
developing well north of the CWA, ahead of a weak boundary draped
across northern Texas, may drift southward, potentially impacting
our northern counties late this afternoon into this evening. POPs
for this activity as well as any seabreeze activity generally remain
under 30%. High temperatures will top out in the upper 90s to 100s
across most locations with overnight lows in the mid 70s to low 80s.

Friday looks more promising in terms of much needed rainfall. As the
low continues to move westward, Gulf moisture will stream into the
area. PWATS will continue to increase to 2 to 2.25 inches and along
with moderate instability we have a better chance of seeing
scattered showers and thunderstorms develop east to west across the
CWA than previous days. While severe weather is not expected, heavy
rainfall (including nuisance flooding and ponding of water on
roadways), frequent lightning and gusty winds are possible with this
activity. The Weather Prediction Center has placed a marginal risk
of excessive rainfall along the coast for Friday. Due to the
increased cloud cover and potential rainfall temperatures will be a
bit cooler for Friday with highs generally in the mid to upper 90s
with a few 100s far west with overnight temperatures generally in
the mid to upper 70s.

LONG TERM (Saturday through Thursday): The long term period starts
off with an increased chance of showers and thunderstorms this
weekend, which will bring some mostly beneficial rain to Deep South
Texas...but there is a marginal threat of some isolated flooding.
This activity will decrease into next week and temperatures will
gradually creep back up to near seasonal normal by the end of the
period.

A mid level inverted trough will move westward across the Northwest
Gulf of Mexico and into Deep South Texas this weekend. Upper level
support from this system combined with deep atmospheric moisture
(PWats expected to be above 2 inches through the weekend...even up
to 2.3 inches on Saturday), will lead to increased shower and
thunderstorm activity Saturday and Sunday. The best chances will be
on Saturday when the mid level inverted trough is more directly
overhead and atmospheric moisture is deepest. This setup will also
lead to the potential for more moderate to heavy rainfall rates,
with the potential for minor localized flooding in affected areas.
Exact timing, location, and rainfall amounts are a bit tricky, but
rainfall amounts from WPC are showing widespread quarter of an inch
to just above an inch across Deep South Texas from Friday through
Sunday (yay for beneficial rain!). However, it's important to note
that models have been picking up on amounts up to 2 to 3 inches with
isolated stronger storms, hence the minor flooding threat,
particularly on Saturday. Regardless, heavy rain, lightning, and
perhaps moderately strong gusts within thunderstorms will pose a
threat to drivers on the road and anyone exposed outside, so take
the proper precautions. With the expected rainfall and cloud
cover, temperatures will be a couple of degrees below normal for
the weekend.

As the mid level inverted trough continues to move off further to
the west, drier air filters in and mid level ridging begins to
dominate once again, rain chances will gradually diminish into mid
week next week and in turn, afternoon high temperatures will
gradually increase back up to near normal. However, there is still a
slight chance that showers and thunderstorms will develop along the
sea breeze on Monday and Tuesday.

MARINE: Today through Friday Night...Generally favorable marine
conditions are expected through the short term period. Light to
moderate winds and seas will prevail. Isolated showers and
thunderstorms are possible over the Gulf Waters through today. As
a mid-level disturbance moves towards the lower Texas coast
tonight into tomorrow, increasing chances of scattered showers and
thunderstorms are expected which could lead to locally enhanced
winds and seas.

Saturday through Wednesday...Marine conditions will be generally
benign through next week due to a relaxed pressure gradient along
the lower Texas coast and high pressure over the Gulf of Mexico.
Light to moderate southeast winds and low to moderate seas can be
expected through the long term. However, shower and thunderstorm
activity will increase this weekend due to an upper level
disturbance passing overhead and deep atmospheric moisture in
place, and conditions will become dangerous at times with this
activity. Small Craft Advisories are not likely to be needed
through the period.

&&

.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL  78  92  77  89 /  20  40  40  40
BROWNSVILLE          79  96  78  91 /  20  50  40  50
HARLINGEN            77  96  76  92 /  10  50  30  50
MCALLEN              78  99  77  94 /  10  50  20  60
RIO GRANDE CITY      78  99  78  95 /  10  50  20  60
SOUTH PADRE ISLAND   80  86  79  84 /  20  40  40  40

&&

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

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

Aviation/Short Term...58-Reese
Radar/Upper Air/Long Term...59-GB

Hazardous Weather Outlook
National Weather Service Brownsville TX
446 PM CDT Thu Aug 11 2022

TXZ248>255-351-353>355-451-454-455-122200-
Zapata-Jim Hogg-Brooks-Inland Kenedy-Starr-Southern Hidalgo-
Inland Willacy-Inland Cameron-Coastal Kenedy-Northern Hidalgo-
Coastal Willacy-Coastal Cameron-Kenedy Island-Willacy Island-
Cameron Island-
446 PM CDT Thu Aug 11 2022

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

.DAY ONE...Tonight

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

Scattered to numerous showers and thunderstorms are forecast for
Friday through Sunday. The heavier or more persistent
thunderstorms will have the ability to produce nuisance flooding
in low-lying and poorly-draining areas, as well as ponding on
local roads.

Heat index values of 103 to 110 degrees are expected during the
afternoon hours on Tuesday and Wednesday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

GMZ130-132-135-150-155-170-175-122200-
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-
Gulf waters from Port Mansfield to the Rio Grande out 20 nm-
Gulf waters from Baffin Bay to Port Mansfield out 20 nm-
Gulf waters from Port Mansfield to the Rio Grande extending from
20 to 60 nm-
Gulf waters from Baffin Bay to Port Mansfield extending from
20 to 60 nm-
446 PM CDT Thu Aug 11 2022

This Hazardous Weather Outlook is for portions of The Gulf of
Mexico and The Laguna Madre.

.DAY ONE...Tonight

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

No hazardous weather is expected at this time.

Scattered to numerous showers and thunderstorms are expected
across the Gulf Waters Friday through Sunday. Gusty winds and
lightning are possible within any thunderstorms along with a low
probability of waterspouts.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

Special Weather Statement
National Weather Service Brownsville TX
626 PM CDT Thu Aug 11 2022

TXZ253-120000-
Southern Hidalgo TX-
626 PM CDT Thu Aug 11 2022

...A strong thunderstorm will impact portions of southwestern Hidalgo
County through 700 PM CDT...

At 626 PM CDT, Doppler radar was tracking a strong thunderstorm 7
miles southeast of Mccook, moving southwest at 20 mph.

HAZARD...Winds in excess of 30 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Mission, Palmview, Palmhurst, Sharyland, Alton, Narciso G. Cavazos
Elementary School, Mission Fire Station Number 3, Abram-Perezville,
Cesar Chavez Middle School and Doffing.

This includes US Highway 83 between mile markers 848 and 850.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 2630 9855 2648 9837 2648 9833 2646 9818
      2646 9817 2644 9814 2615 9830
TIME...MOT...LOC 2326Z 033DEG 18KT 2644 9828

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...30 MPH

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