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Marine Weather and Tide Forecast for Port Mansfield, TX


May 18, 2026 6:42 AM CDT (11:42 UTC)
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Sunrise 6:42 AM   Sunset 8:11 PM
Moonrise 7:08 AM   Moonset 9:49 PM 
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NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION.

Marine Forecasts
   
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NOTE: Zones updated 4/16/2026. Some zones changed. Use Edit if needed.
GMZ132 Expires:202605181915;;754169 Fzus54 Kbro 180648 Cwfbro
coastal waters forecast for the lower texas coast national weather service brownsville tx 148 am cdt Mon may 18 2026
lower texas coastal waters from baffin bay to the mouth of the rio grande out 60 nm.
seas are provided as a range of the average height of the highest 1/3 of the waves, along with the occasional height of the average highest 10 percent of the waves.
gmz130-132-135-181915- 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- 148 am cdt Mon may 18 2026

.small craft advisory in effect through Tuesday morning - .

Today - Southeast winds 15 to 20 knots. Gusts to 30 knots late this afternoon. Choppy on the bay. A slight chance of showers this morning.

Tonight - Southeast winds 15 to 20 knots. Choppy on the bay. A slight chance of showers and Thunderstorms in the late evening and overnight.

Tuesday - Southeast winds around 15 knots. A moderate chop on the bay. A slight chance of showers. A slight chance of Thunderstorms in the afternoon.

Tuesday night - Southeast winds 10 to 15 knots. A moderate chop on the bay. A chance of showers with a slight chance of Thunderstorms after midnight.

Wednesday - Southeast winds 10 to 15 knots. A moderate chop on the bay. A chance of showers early in the morning.

Wednesday night - Southeast winds 10 to 15 knots. A moderate chop on the bay.

Thursday - Southeast winds 5 to 10 knots, increasing to 10 to 15 knots in the afternoon. A moderate chop on the bay. A slight chance of Thunderstorms until late afternoon. A chance of showers.

Thursday night - Southeast winds 10 to 15 knots, diminishing to 5 to 10 knots after midnight. A moderate chop on the bay, diminishing to light chop after midnight. A chance of showers in the evening. A slight chance of Thunderstorms late in the evening, then showers likely with a chance of Thunderstorms after midnight.

Friday - South winds 5 to 10 knots, becoming southeast 10 to 15 knots in the afternoon. A moderate chop on the bay. A chance of Thunderstorms. Showers likely.

Friday night - Southeast winds 10 to 15 knots, diminishing to 5 to 10 knots in the late evening and overnight. A moderate chop on the bay, diminishing to light chop in the late evening and overnight. A chance of showers. A chance of Thunderstorms early in the evening, then a slight chance of Thunderstorms in the late evening and overnight.
winds and waves higher in and near Thunderstorms.
GMZ100 148 Am Cdt Mon May 18 2026

Synopsis - An enhanced pressure gradient will maintain unfavorable marine conditions with moderate to fresh southeasterly winds, moderate seas, and choppy bay conditions through much of the week. Low to medium (30 to 60 percent) rain chances return Tuesday night, lasting through the week.

7 Day Forecast for Marine Location Near Port Mansfield, TX
   
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NEW! Add second zone forecast

Tide / Current for Padre Island, Port Mansfield Channel ent., Texas
  
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Padre Island
Click for Map
Mon -- 06:40 AM CDT     Sunrise
Mon -- 07:37 AM CDT     1.98 feet High Tide
Mon -- 08:07 AM CDT     Moonrise
Mon -- 08:10 PM CDT     Sunset
Mon -- 10:37 PM CDT     -0.60 feet Low Tide
Mon -- 10:47 PM CDT     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
        
  Sorry, Padre Island, Port Mansfield Channel ent., Texas does not exist in database. Press Edit above and select a valid nearby location.

Padre Island, Port Mansfield Channel ent., Texas, Tide feet
12
am
-0.2
1
am
0.1
2
am
0.6
3
am
1.1
4
am
1.5
5
am
1.8
6
am
1.9
7
am
2
8
am
2
9
am
2
10
am
1.9
11
am
1.8
12
pm
1.7
1
pm
1.6
2
pm
1.5
3
pm
1.4
4
pm
1.2
5
pm
0.9
6
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0.6
7
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0.2
8
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-0.2
9
pm
-0.4
10
pm
-0.6
11
pm
-0.6

Tide / Current for ICW Laguna Madre, 2.25 nmi S of Arroyo Colorado Cut (depth 3 ft), Texas Current
  
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ICW Laguna Madre
Click for Map Flood direction 347 true
Ebb direction 164 true

Mon -- 03:35 AM CDT     -0.56 knots Max Ebb
Mon -- 06:41 AM CDT     Sunrise
Mon -- 08:08 AM CDT     Moonrise
Mon -- 08:31 AM CDT     0.00 knots Slack
Mon -- 01:54 PM CDT     0.57 knots Max Flood
Mon -- 08:10 PM CDT     Sunset
Mon -- 10:18 PM CDT     -0.00 knots Slack
Mon -- 10:47 PM CDT     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
        
  Sorry, ICW Laguna Madre, 2.25 nmi S of Arroyo Colorado Cut (depth 3 ft), Texas Current does not exist in database. Press Edit above and select a valid nearby location.

ICW Laguna Madre, 2.25 nmi S of Arroyo Colorado Cut (depth 3 ft), Texas Current, knots
12
am
-0.3
1
am
-0.4
2
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-0.5
3
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-0.6
4
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-0.6
5
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-0.5
6
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-0.4
7
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-0.3
8
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-0.1
9
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0.1
10
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0.3
11
am
0.4
12
pm
0.5
1
pm
0.6
2
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0.6
3
pm
0.6
4
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0.5
5
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0.5
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0.4
7
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0.3
8
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0.3
9
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0.2
10
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0
11
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-0.1

Area Discussion for Brownsville, TX
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NOTE: mouseover dotted underlined text for definition
FXUS64 KBRO 181108 AAB AFDBRO

Area Forecast Discussion...UPDATED National Weather Service Brownsville TX 608 AM CDT Mon May 18 2026

New AVIATION

KEY MESSAGES
Updated at 605 AM CDT Mon May 18 2026

Key Messages:

* Daily or near daily chances for showers and thunderstorms is expected through the upcoming workweek and possibly through the end of May as a major shift in the weather pattern takes shape.

* Strong to severe thunderstorms along with heavy rainfall and localized flooding is possible through the upcoming workweek.

* Hot and humid conditions will take place through Tuesday; maximum heat indices between 105-111F degrees will result in widespread Moderate (Level 2 of 4) to Major (Level 3 of 4) Heat Risk through Tuesday.

* A Small Craft Advisory has been extended till 9 AM CDT Tuesday; a High Risk for Rip Currents may need to be expected till Tuesday as well.

UPDATE
Issued at 1228 AM CDT Mon May 18 2026

Collaborated higher POPs through Tuesday afternoon with our neighboring office, given showers and thunderstorms actively on radar across the brush country and upper valley. Leaned into more of a diurnal cycle from west to east into Monday morning and Tuesday morning.

DISCUSSION
Issued at 1028 PM CDT Sun May 17 2026

Building heat with Moderate (Level 2 of 4) to Major (Level 3 of 4)
Heat Risk through Tuesday (possibly into Wednesday), and an increasingly unsettled weather pattern punctuating a significant pattern change from dry to wet are the two main weather headlines through the forecast period. We'll first begin talking about the unsettled weather pattern followed by the building heat through midweek.

Global computer and AI/ML models/ensembles continues to advertise a significant pattern change from dry to wet beginning this week. A split-flow 500 mb pattern featuring what will become an increasingly active and persistent southwest flow aloft sub-tropical jet or southern branch jet stream is in place. This will serve as a conduit for multiple impulses/perturbations tracking over the region over the next several days. Later in the week through next weekend, there are sings that mid-upper troughing along with multiple impulses/perturbations will undercut high pressure/ridging aloft. This large-scale setup will help to yield incessant day-to-day or near day-to-day chances for showers and thunderstorms through at least next week and maybe through the remainder of May.

Closer to the sfc, a frontal boundary will sag southward across the U.S. before stalling and meandering to our north across the southern Plains. More than normal favorable jet dynamics will be in place through next week. Additionally, southerly flow near the sfc will yield a pool of deep tropical moisture helping to increase the atmospheric water content over the region through the week ahead. This is justified with sample maximum precipitable water (PWAT) values between 1.80-2.50 inches, some 1-3 STDEVs above normal and above the 90th percentile of sounding climatology for mid to late May. Furthermore, high instability values will be present through this week with steep mid level lapse rates between 6.5-8.0 C/km, SBCAPE values between 2,000-4,000 J/kg, MLCAPE values between 1,000- 2,000 J/kg, a moderately to very unstable atmosphere with Showalter values ranging between -2 and -6.

The combination of a favorable mid-upper level 500 mb steering pattern, favorable jet stream dynamics, high atmospheric moisture content, and high instability will support a noticeable change to a wetter/active weather pattern this week and possibly beyond.
Strong to severe thunderstorms are possible given the atmospheric and forcing ingredients highlighted above. The Storm Prediction Center (SPC) has highlighted the northwestern half of our area under a Marginal Risk (Level 1 of 5) for severe thunderstorms on Tuesday. This includes all of Zapata and Jim Hogg Counties, and most of Brooks and Starr Counties in it's latest SWODY3.

Given the high atmospheric moisture content available, heavy rainfall and instances of flooding is possible through the week, especially later in the week. This is especially true for slow moving thunderstorms that repeatedly track over the same areas.
The Weather Prediction Center (WPC) has placed the entire forecast area or all of Deep South Texas under a Marginal Risk (Level 1 of 4) for Excessive Rainfall in it's Day 4 (Wednesday) and Day 5 (Thursday) ERO.

Most of the convection through next week is anticipated to initiate off the Sierra Madre before possibly rolling off the front range and translating east-northeastward into our CWA So far, for Monday night, low (20%) chance PoPs are forecasted generally along the Rio Grande Valley. Tuesday night, rain chances increase with low-medium (30-40%) PoPs for showers and thunderstorms.
Wednesday-Wednesday night, there is a low-medium (20-40%) chances for showers and thunderstorms. Thursday will feature medium (30-60%) chances. By Thursday night, rain chances increase with widespread categorical or medium-high (50-80%) chances. Friday through Saturday, there remain medium (30-60%) chances across Deep South Texas. Finally, Saturday night through next Monday, there exists medium (30-50%) chances. Overall, there generally is a 30-60% chance for showers and thunderstorms through the forecast period with Thursday night yielding the greatest chances between 50-80%.

The other news will be the heat! Global forecast models/ensembles continue to depict a strengthening 588-591 dam sub-tropical heat ridge developing over the region early next week. This feature will result in hotter than normal temperatures through Tuesday, and maybe even extending into Wednesday. Forecast high temperatures for Monday and Tuesday are expected to be in the mid 90s to lower 100s with the hottest temps west of IH-69C/US-281. Dewpoints in the mid 70s will result in max heat indices or apparent temperature values climbing to between 105-111F degrees on both Monday and Tuesday. These values will result in Moderate (Level 2 of 4) to Major (Level 3 of 4) Heat Risk both days. Cloud over will be a factor in these temperatures being realized.

By Wednesday, the aforementioned heat ridge relaxes which should result in a slightly cooler day. Shower and thunderstorm chances Tuesday night into Wednesday as well as cloud cover could also play a role in the slightly lower temperatures from Monday and Tuesday.
Nonetheless, it will be another warmer than normal day with high temperatures in the low to mid 90s. With heat indices ranging between 100-108F degrees, Heat Risk scores will be mainly Moderate (Level 2 of 4) over the region on Wednesday.

Thursday through next Sunday, high temperatures will range between the upper 80s to lower 90s. This largely will be due to the shower and thunderstorm chances during this timeframe. Tonight through Tuesday night, overnight lows are progged to be in the upper 70s to lower 80s. Wednesday night through next Sunday night, overnight lows are expected to be mainly in the 70s.

AVIATION
(12Z TAFS)
Issued at 605 AM CDT Mon May 18 2026

VFR and MVFR conditions are expected to improve this morning to all VFR with breezy to gusty southeasterly winds. MVFR ceilings likely return this evening through tonight. Isolated thunderstorms may develop west of MFE tonight and work towards the RGV aerodromes into Tuesday morning. Confidence is too low to include in this TAF package.

MARINE
Issued at 1028 PM CDT Sun May 17 2026

A Small Craft Advisory has been extended till Tuesday morning due to continued breezy southeasterly winds and elevated wave heights.
Outside of the threat for showers and thunderstorms, Tuesday through Wednesday, adverse (Small Craft Exercise Caution) conditions are possible. Again, outside of the threat for showers and thunderstorms Wednesday night through next Sunday, marine conditions are expected to improve with moderate seas and low to moderate winds.

PRELIMINARY POINT TEMPS/POPS
BROWNSVILLE 95 81 94 81 / 20 20 20 20 HARLINGEN 96 79 95 79 / 20 20 20 40 MCALLEN 97 81 97 79 / 20 30 20 30 RIO GRANDE CITY 99 79 98 78 / 20 30 20 40 SOUTH PADRE ISLAND 86 81 86 81 / 20 20 20 20 BAYVIEW/PORT ISABEL 93 80 92 80 / 20 20 20 30

BRO WATCHES/WARNINGS/ADVISORIES
TX...High Rip Current Risk through Tuesday evening for TXZ451-454-455.

GM...Small Craft Advisory until 9 AM CDT Tuesday for GMZ130-132-135- 150-155-170-175.


Weather Reporting Stations
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Stations Dist Age Wind AirWater WavesinHgDewPt
PMNT2 2 mi55 min 29.77
RSJT2 - 8777812 - Rincon del San Jose; Potrero Lopeno SW, TX 18 mi55 minSSE 28G32 29.74
RLIT2 20 mi55 minSSE 20G25 29.77
BZST2 35 mi55 minSE 12G13 29.78
PCGT2 - 8779748 - South Padre Island CGS, TX 35 mi55 minSE 12G14 29.79
PTIT2 - 8779770 - Port Isabel, TX 35 mi55 minSE 11G15 29.81


Wind History for Rincon Del San Jose, TX
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Airport Reports
   
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AirportDistAgeWind ktVisSkyWeatherAirDewPtRHinHg
KHRL25 sm50 minSSE 13G2010 smClear79°F75°F89%29.79

Weather Map
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GEOS Local Image of gulf of mexico  
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Brownsville, TX,





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