Port Mansfield, TX to the Rio Grande River Marine Forecast
|Rest Of Tonight...North Winds 25 To 35 Knots. Seas 2 To 4 Feet Building To 7 To 11 Feet With Occasional Seas Up To 13 Feet After Midnight. Chance Of Rain Showers And Slight Chance Of Thunderstorms Late In The Evening, Then Rain Showers Likely After Midnight.|
|Tuesday...North Winds 25 To 35 Knots Diminishing To 20 To 30 Knots In The Afternoon. Seas 8 To 12 Feet With Occasional Seas Up To 14 Feet. Rain In The Morning, Then Chance Of Rain In The Afternoon.|
|Tuesday Night...North Winds 15 To 25 Knots Becoming 15 To 20 Knots After Midnight. Seas 6 To 9 Feet With Occasional Seas Up To 10 Feet. Slight Chance Of Rain.|
|Wednesday...North Winds 10 To 15 Knots Diminishing To 5 To 10 Knots In The Afternoon. Seas 4 To 6 Feet With Occasional Seas Up To 7 Feet. Slight Chance Of Rain Showers.|
|Wednesday Night...North Winds 5 To 10 Knots. Seas 2 To 4 Feet. Chance Of Rain Showers.|
|Thursday...North Winds 10 To 15 Knots Increasing To 15 To 20 Knots In The Afternoon. Seas 2 To 4 Feet. Rain Showers Likely And Slight Chance Of Thunderstorms.|
|Thursday Night...North Winds 15 To 20 Knots. Seas 5 To 7 Feet With Occasional Seas Up To 8 Feet. Showers Likely And Slight Chance Of Thunderstorms.|
|Friday...North 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. Chance Of Showers.|
|Friday Night...North Winds 10 To 15 Knots Diminishing To 5 To 10 Knots After Midnight. Seas 3 To 5 Feet.|
|Saturday...Northeast Winds 5 To 10 Knots. Seas 2 To 4 Feet.|
|Saturday Night...Southeast Winds 5 To 10 Knots. Seas 2 To 3 Feet.|
Synopsis for Baffin Bay to Rio Grande out 60 nm: GMZ100|
954 PM CST Mon Nov 11 2019
Very strong north to northeast winds and high seas will continue tonight and Tuesday in the wake of a cold front. Conditions will improve on Wednesday as high pressure spreads over the northwest Gulf.
Area Forecast Discussion|
...UPDATED National Weather Service Brownsville TX
529pm CST Monday Nov 11 2019
..Arctic cold front heading for the Rio Grande Valley and northern ranchlands tonight... Short Term - Now through Tuesday night
Temperatures continue to fall below freezing across portions of the Texas panhandle and northwest Texas this afternoon as an arctic airmass continues to move southward in the wake of a strong cold front moving through central Texas into south Texas. The front is expected to reach the northern ranchlands this evening and move into the Rio Grande Valley by midnight. Showers and isolated thunderstorms are expected to develop along and ahead of the front tonight before becoming elevated late tonight into early Tues morning. Rain chances will increase this evening and remain high through Tues afternoon. The main impacts in the wake of the cold front will be temperatures and winds. 12Z NAM models soundings indicate the potential for some frozen precipitation across the northern ranchlands Tues morning so will mention a slight chance of sleet for northwest portions of the CWA but no ice accumulations are expected. In addition...temperatures at the surface will remain above freezing tonight into Tuesday so no freezing rain is expected but cannot rule out some patchy freezing rain on elevated surfaces where temperatures fall to freezing. Strong north winds will develop in the wake of the front tonight and will continue across the CWA through Tues afternoon. Wind advisories are currently in effect for the coastal sections of deep south Texas tonight through Tuesday. With the strong northerly winds and falling temperatures tonight into Tues morning...wind chill temperatures will fall into the 20s across most of the CWA Tues morning and continue below 30 degrees through Tues afternoon. Wind chill advisories are in effect for the northern ranchlands Tues morning through early Tues afternoon and for the rest of deep south Texas Tues afternoon through early Tues evening. Temperatures will be most challenging part of the forecast tonight into Tuesday as the model blends appear to warm in the short term due to the fact that most of the global models cannot handle the shallow nature of the arctic airmass. Will go with a blend of the ADJMET and ADJMAV MOS guidance for hourly temperatures to reflect the shallow nature of the airmass as well as the strength of the cold air advection. As a result...temperatures will likely continue to fall Tues morning into early Tues afternoon before becoming steady. Will likely tie or break record low temperatures tonight and Tues night as well as tie or break the record low maximum temperatures for Tuesday (see current record temps in climate section below).
Also...we have issued a coastal flood advisory for coastal Cameron tonight into Tuesday as we will likely see water levels rise to near 2 feet MHHW across the southern portions of the Laguna Madre as the strong north winds and high tides allow minor coastal flooding to develop along the southern coastal sections of the bay.
Thanks to our neighboring forecast office in Corpus Christi (WFO CRP) for collaboration on the forecast and advisories/warnings impacting our areas tonight into Tuesday.
Long Term - Wednesday through Monday
For the majority of the long term period, expect overcast skies and cooler than normal temperatures for this time of year with a gradual increase to near normal temperatures by the end of the weekend. The best chance for rain will be Wednesday evening through Thursday.
On Wednesday, the surface high pressure that moved in behind the front will continue to slide east and a mid-level shortwave will approach our area from the west. Ahead of this shortwave, models are indicating that pockets of energy and increased 1000-500 mb layer moisture will be advected into Deep South Texas Wednesday afternoon/evening. For this reason, have kept slight chance Probability of Precipitation for the Rio Grande Valley and coastal areas during the day on Wednesday and have increased Probability of Precipitation across the CWA Wednesday night into Thursday as the shortwave passes overhead. Temperatures will be well below normal on Wednesday with lows in the mid to upper 30s warming into the mid to upper 50s by the afternoon. Thursday will be slightly warmer than Wednesday, starting off in the mid to upper 40s and warming into in the low to mid 60s in the afternoon.
As the shortwave exits the region Thursday night and ridging builds overhead again, drier and warmer conditions are expected to follow on Friday and Saturday. Beyond Saturday, model solutions begin to diverge more significantly, decreasing forecast confidence. Have gone ahead and included slight chance Probability of Precipitation on Sunday as some models are picking up on a small shortwave/trough with increased moisture passing through central Texas that afternoon/evening.
Marine - Tonight through Tuesday night
Seas were near 3 feet with south to southeast winds near 10 knots at buoy020 this afternoon. Light winds across the coastal waters this evening will shift to the north and increase to gale force conditions in the wake of a strong arctic cold front moving from north to south tonight. Very strong north winds will prevail across the coastal waters tonight into Tuesday as the pressure gradient increases and remains very strong across the western Gulf of Mexico. Gale warnings are already in effect for the Laguna Madre and the offshore waters tonight through Tues afternoon. Winds will begin to diminish across the lower Texas coast Tues afternoon into Tues evening and offshore Tues evening through Tues night. Small craft advisories will likely replace the Gale warnings for the Laguna Madre and offshore waters Tues evening and will continue for the offshore waters Tues night as seas remain high.
Wednesday through Saturday: Adverse marine conditions are expected to persist through Wednesday morning, and then die down through Thursday morning as the pressure gradient begins to weaken. Thursday afternoon, winds and seas will pick up again as an upper level disturbance passes overhead and the pressure gradient increases, and conditions will remain elevated through Friday. Small Craft Advisories may be needed briefly on Thursday afternoon/evening.
CLIMATE...Here are the possible record lowest minimum temperatures that might be tied or broken the next couple of days.
Tuesday, Nov 12th: Brownsville 36...*Harlingen 45...and McAllen 38. Wednesday, Nov 13th: Brownsville 38...*Harlingen 38...and McAllen 38.
In addition, here are the record lowest maximum temperatures the next couple of days.
Tuesday, Nov 12th: Brownsville 45...*Harlingen 55...and McAllen 56. Wednesday, Nov 13th: Brownsville 49...*Harlingen 49...and McAllen 45.
*Climate records for Valley International Airport
NOAA Brownsville TX Office: Watches - Warnings - Advisories
TX...Wind Advisory until 6pm CST Tuesday for TXZ251-254>257-351.
Wind Chill Advisory from 8am to 1pm CST Tuesday for TXZ248>251- 351.
Wind Chill Advisory from 8am to 6pm CST Tuesday for TXZ252>257- 353.
Coastal Flood Advisory from 10pm this evening to 6pm CST Tuesday for TXZ257.
GM...Gale Warning until 6pm CST Tuesday for GMZ130-132-135-150-155- 170-175.