Port Mansfield, TX to the Rio Grande River Marine Forecast
|Rest Of Tonight...South Winds 15 To 20 Knots. Seas 3 To 5 Feet. Areas Of Fog.|
|Friday...Southeast Winds 10 To 15 Knots. Seas 2 To 4 Feet. Areas Of Fog In The Morning, Then Patchy Fog In The Afternoon.|
|Friday Night...Southeast Winds 10 To 15 Knots. Seas 2 To 4 Feet. Areas Of Fog.|
|Saturday...Southeast Winds 10 To 15 Knots. Seas 2 To 4 Feet. Areas Of Fog In The Morning.|
|Saturday Night...Southeast Winds 10 To 15 Knots. Seas 3 To 5 Feet. Patchy Fog.|
|Sunday...Southeast Winds 10 To 15 Knots. Seas 3 To 5 Feet. Patchy Fog In The Morning.|
|Sunday Night...Southeast Winds 10 To 15 Knots. Seas 3 To 5 Feet.|
|Monday...East Winds 5 To 10 Knots. Seas 3 To 5 Feet. Slight Chance Of Showers And Thunderstorms.|
|Monday Night...East Winds 5 To 10 Knots. Seas 3 To 5 Feet. Slight Chance Of Showers.|
|Tuesday...North Winds 10 To 15 Knots. Seas 4 To 6 Feet With Occasional Seas Up To 7 Feet. Slight Chance Of Showers.|
|Tuesday Night...Northeast Winds 10 To 15 Knots Becoming East 5 To 10 Knots After Midnight. Seas 4 To 6 Feet With Occasional Seas Up To 7 Feet.|
| Synopsis for Baffin Bay to Rio Grande out 60 nm: GMZ100|
912 PM CST Thu Feb 25 2021
Marine fog will continue to affect the Laguna Madre and nearshore Gulf waters tonight into Friday morning. Persistent moderate to strong south to southeast winds will develop through the weekend, leading to elevated seas on the Gulf. A weak cold front will move into the area on Monday shifting winds to northeast by Monday night.
| Area Forecast Discussion|
...UPDATED National Weather Service Brownsville TX
1144pm CST Thu Feb 25 2021
AVIATION...MVFR (Marginal Visual Flight Rules) ceilings will prevail over BRO, HRL and MFE with brief periods of VFR overnight, mainly at HRL and MFR, and BRO also seeing brief periods of IFR. Southerly winds will remain moderate overnight. VFR conditions will return to MFE before daybreak and HRL and BRO by mid Friday morning.
AVIATION...Satellite and surface observations are showing VFR conditions over all aerodromes. MVFR (Marginal Visual Flight Rules) conditions are expected to develop over the next few hours across all terminals and prevail through late Friday morning for HRL and MFE. BRO will see MVFR ceilings then IFR through much of the overnight before returning to MVFR (Marginal Visual Flight Rules) and finally VFR by late morning. Gusty winds will begin to decrease this evening but remain moderate overnight into early Friday.
Short Term - Now through Friday Night
A weak cold front is perched just north of the CWA this afternoon as moderate southeast to south return flow continues locally. Looks like the front may push south into the ranchlands overnight, but progress will be slow. Patchy fog may develop ahead of the front in those areas. Isolated showers may also develop, but probabilities are low and mention was omitted in the forecast for now. The same goes for any coastal shower chances. In the meantime, Gulf advection fog will continue, but will mainly affect South Padre Island due to the wind direction. The combination of return flow, zonal flow aloft, and lack of a strong cold air push from the north will doom the weak front to stall out and head back north late Friday and Friday night. Short term low temps for the CWA will be in the 60s both nigheights with Friday high temps in the 70s and lower 80s under mostly cloudy skies.
Long Term - Saturday through Thursday
Southwesterly flow aloft continues through the weekend with high pressure across the eastern Gulf of Mexico and weak low pressure across the Plains fueling warm southerly flow across Deep South Texas. Expect temperatures to remain well above normal, into the 80s. A 500mb shortwave drops down into the Four Corners area Sunday into Monday before exiting eastward across Texas Monday afternoon into Tuesday.
At the surface, a cold front arrives into central and southern Texas on Monday, bringing back a chance of rain and a slight chance of thunderstorms. Expect above normal temperatures still on Monday, likely topping off in the mid to upper 70s. The front works through Deep South Texas Tuesday morning, with a continuing chance of rain, especially across the coast, and highs barely reaching 70 degrees. Southerly flow briefly returns on Wednesday, with highs into the upper 70s to low 80s. A weak front or northerly wind shift arrives Thursday morning as high pressure builds across the region, with highs still warming into the upper 70s to low 80s. With lower humidity, Thursday should be quite comfortable.
Patchy to areas of marine fog are still likely Saturday and possible both Sunday and Monday.
Marine - Now through Friday night
Favorable conditions for marine fog will continue. Thus, fog development will remain problematic in the short term. Dense fog conditions requiring advisories will at times be possible. Otherwise, moderate to fresh southeast to south winds will support moderate seas, and small craft should exercise caution conditions will be possible at times.
Saturday through Thursday: High pressure across the eastern Gulf of Mexico and low pressure across the Plains continues moderate southerly flow along the lower Texas coastal waters this weekend. A cold front arrives by Tuesday morning, with breezy northeasterly winds and elevated seas into Tuesday night. Easterly to southeasterly flow briefly returns on Wednesday before another northerly wind shift arrives on Thursday elevating seas once again. Small Craft Caution conditions are possible over the weekend, with a brief period of SCEC to SCA (Small Craft Advisory) conditions on Tuesday. Light to moderate seas continue Wednesday into Thursday.
Patchy to areas of marine fog are still likely Saturday and possible both Sunday and Monday. Visibility may be reduced at times to less than 1 nautical mile, especially on Saturday.
NOAA Brownsville TX Office: Watches - Warnings - Advisories
TX...None. GM...Dense Fog Advisory until 10am CST Friday for GMZ130-132-135-150- 155.