Port Mansfield, TX to the Rio Grande River 20 - 60 NM Marine Forecast
|Tonight...Southeast Winds 15 To 20 Knots. Seas 5 To 8 Feet With Occasional Seas Up To 9 Feet.|
|Saturday...Southeast Winds 15 To 20 Knots Diminishing To 10 To 15 Knots In The Afternoon. Seas 5 To 7 Feet With Occasional Seas Up To 8 Feet. Haze In The Morning.|
|Saturday Night...Southeast Winds 15 To 20 Knots Diminishing To 10 To 15 Knots After Midnight. Seas 5 To 7 Feet With Occasional Seas Up To 8 Feet.|
|Sunday...East Winds 10 To 15 Knots. Seas 5 To 7 Feet With Occasional Seas Up To 8 Feet. Slight Chance Of Showers And Thunderstorms In The Afternoon.|
|Sunday Night...Southeast Winds 15 To 20 Knots. Seas 5 To 7 Feet With Occasional Seas Up To 8 Feet. Slight Chance Of Showers And Thunderstorms After Midnight.|
|Monday...Southeast Winds 10 To 15 Knots Increasing To 15 To 20 Knots In The Afternoon. Seas 5 To 7 Feet With Occasional Seas Up To 8 Feet. Chance Of Showers And Thunderstorms In The Morning, Then Slight Chance Of Showers And Thunderstorms In The Afternoon.|
|Monday Night...Southeast Winds 15 To 20 Knots. Seas 5 To 7 Feet With Occasional Seas Up To 8 Feet. Slight Chance Of Showers And Thunderstorms.|
|Tuesday...Southeast Winds 15 To 20 Knots. Seas 6 To 8 Feet With Occasional Seas Up To 9 Feet. Slight Chance Of Showers And Thunderstorms.|
|Tuesday Night...Southeast Winds 15 To 20 Knots. Seas 6 To 8 Feet With Occasional Seas Up To 9 Feet.|
|Wednesday...Southeast Winds 15 To 20 Knots. Seas 5 To 7 Feet With Occasional Seas Up To 8 Feet. Slight Chance Of Showers And Thunderstorms.|
|Wednesday Night...Southeast Winds 15 To 20 Knots. Seas 5 To 7 Feet With Occasional Seas Up To 8 Feet. Chance Of Showers And Thunderstorms.|
| Area Forecast Discussion|
National Weather Service Brownsville TX
308pm CDT Fri May 20 2022
Short Term - Now through Saturday Night
Satellite and radar images continue to indicate isolated convection developing across portions of Zapata...Jim Hogg and Starr counties this afternoon. As the 500mb shortwave trough across southwest Texas continues to move across southwest Texas through the rest of the afternoon into early this evening...will continue to see isolated showers and thunderstorms develop across western portions of the brush country and the Rio Grande Plains into the northern ranchlands this evening.
Strong southerly winds continue across the coastal counties of deep south Texas this afternoon with wind gusts of 40 to 45 mph reported at the ASOS sites at KBRO...KHRL and KPIL within the last hour. Will continue the Wind Advisory for Cameron...Willacy and Kenedy counties through 8 pm this evening.
A weak cold front will move into central Texas Saturday and move into south Texas Sat night before stalling to the north of deep south Texas. Not much in the way of rain chances are expected through the rest of the short term forecast period. The main concern will be temperatures Saturday with near record highs possible across portions of the Rio Grande Valley Saturday afternoon (Record high temperature for McAllen tomorrow is 100 degrees set in 1957.) In addition...with dewpoints in the lower to middle 70s...heat index values will approach Heat Advisory criteria across portions of Brooks...Kenedy...northern Hidalgo and Willacy counties Sat afternoon.
Long Term - Sunday through Friday
Mid-level subtropical ridging over Deep South Texas this weekend will gradually flatten into early next week as a large-scale trough digs into much of the central CONUS by midweek. At the surface, a weak cold front will be advancing south into southern Texas Sunday morning. The weak frontal boundary is forecast to stall just north of the Northern Ranchlands Sunday afternoon/evening. However, the tail-end of the front may push across Zapata and portions of Jim Hogg and Starr Counties before stalling. PWATs (Precipitable Waters) may vary across the district, but will essentially rise above 1.5” to nearly 2.0” in spots Sunday afternoon. There should be enough moisture and lift along and ahead of the boundary to produce isolated to scattered showers and thunderstorms beginning Sunday afternoon, with best chances occurring across the four northern counties. Scattered showers and thunderstorms will continue through Monday as the mid-level trough axis remains upstream and the stationary boundary begins to lift northward.
Medium-range deterministic ECMWF (European Centre for Medium-Range Weather Forecasts) and GFS models continue to agree on a robust shortwave trough pivoting across southwest Texas late Monday afternoon and into south/south-central Texas Monday evening/night. Both models produce a Mesoscale Convective System and push it through much of South Texas. There's still a lot of questions on exact position/location of the shortwave and environmental stability over Deep South Texas. Latest ECMWF has a weaker cap in place and pushes the MCS through much/all of the BRO CWA late Monday night into early Tuesday morning. Meanwhile, the GFS has a more stable environment in place, keeping the majority of the thunderstorm activity just north of the CWA. Will continue to monitor trends.
The weather pattern remains fairly active into the midweek, even as mid/upper-level subtropical riding tries to build back in over Deep South Texas. Another weak surface cold front will push south into Texas on Wednesday. Although confidence remains low, it appears this frontal boundary may push through all of Deep South Texas either Wednesday evening or Thursday morning. Still lots of discrepancies in the long-range forecast models. Stay tuned.
As far as temperatures are concerned, temperatures will be trending cooler into early next week, with temperatures closer to seasonal average on Monday and Tuesday, as cloud cover and precipitation chances increase through the upcoming week. Temperatures will increase on Wednesday, ahead of the approaching weak front, with temperatures dipping slightly below seasonal average Thursday and Friday behind the front.
ow through Saturday night): Seas were near 8 feet with south to southeast winds near 18 knots at buoy020 at 1:30 pm today. Strong southeast winds will prevail across the coastal waters tonight as the pressure gradient remains strong across the lower Texas coast this evening. Will extend the SCA (Small Craft Advisory) for the Laguna Madre through midnight tonight and the SCA (Small Craft Advisory) for the offshore waters through Saturday morning as winds should diminish slightly after midnight but seas will remain elevated offshore late tonight into Sat morning. SCEC to SCA (Small Craft Advisory) conditions will prevail across the coastal Saturday into Sat night as moderate to strong southeast winds prevail across the coastal waters and seas remain elevated offshore the lower Texas coast.
Sunday through Wednesday: SCEC conditions (Small Craft Should Exercise Caution) will continue into Sunday, mostly concentrated across the offshore Gulf waters. The pressure gradient will briefly relax some during the day on Sunday as a weak cold front pushes into southern Texas Sunday afternoon/evening. Moderate to strong southerly winds will return Sunday night and continue through Monday bringing back SCEC conditions. Winds may become strong enough to prompt Small Craft Advisories beginning Monday night and may continue into Tuesday night. Winds and seas will decrease some on Wednesday, with SCEC conditions possible.
NOAA Brownsville TX Office: Watches - Warnings - Advisories
TX...Wind Advisory until 8pm CDT this evening for TXZ251-254-255-351- 354-355-451-454-455.
High Rip Current Risk through Saturday evening for TXZ451-454- 455.
GM...Small Craft Advisory until midnight CDT tonight for GMZ130-132- 135.
Small Craft Advisory until 7am CDT Saturday for GMZ150-155-170- 175.