Port Mansfield, TX to the Rio Grande River Marine Forecast
|Today...Northwest Winds 10 To 15 Knots Becoming North 15 To 25 Knots In The Afternoon. Seas 5 To 8 Feet With Occasional Seas Up To 9 Feet. Rain Showers Likely In The Morning, Then Chance Of Rain Showers In The Afternoon.|
|Tonight...North Winds 15 To 25 Knots. Seas 6 To 9 Feet With Occasional Seas Up To 10 Feet. Chance Of Rain Showers In The Evening, Then Slight Chance Of Rain Showers After Midnight.|
|Friday...North Winds 15 To 20 Knots. Seas 5 To 8 Feet With Occasional Seas Up To 9 Feet.|
|Friday Night...North Winds 10 To 15 Knots Becoming Northeast 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...East Winds 5 To 10 Knots Shifting Southeast After Midnight. Seas 2 To 4 Feet.|
|Sunday...Southeast Winds 5 To 10 Knots. Seas 2 To 3 Feet. Slight Chance Of Showers.|
|Sunday Night...South Winds 5 To 10 Knots Shifting West After Midnight. Seas 2 To 3 Feet. Slight Chance Of Showers.|
|Monday...Northwest Winds 10 To 15 Knots Becoming North 5 To 10 Knots In The Afternoon. Seas 2 To 3 Feet.|
|Monday Night...North Winds 5 To 10 Knots Diminishing To Around 5 Knots After Midnight. Seas 2 To 3 Feet.|
Synopsis for Baffin Bay to Rio Grande out 60 nm: GMZ100|
348 AM CST Thu Nov 14 2019
Favorable marine conditions will continue this morning. However, conditions will deteriorate by noon today into Friday due to reinforcing high pressure and weak coastal troughing, producing strong northerly winds. A mid level disturbance and coastal troughing will also contribute to increased rain chances into Friday. More favorable conditions will return this weekend before the next cold front arrives Sunday night.
Area Forecast Discussion|
...UPDATED National Weather Service Brownsville TX
532am CST Thu Nov 14 2019
Short Term - Today Through Friday
BRO radar continues to show light to moderate showers moving west to east across much of the CWA this morning, with the heaviest rain occurring over the coastal counties. This rainfall is associated with a mid-level cut-off low that is currently over the Mexican state of Coahuila, as of 08z/2am CST. Showers are expected to continue through most of the morning as the mid-level low continues to drift east- northeastward through the day. Similarly to yesterday morning, cloud cover and rain are keeping temperatures in the low-mid 40s across the district. However, one difference from yesterday morning is much lighter north/northwest winds occurring this morning.
The aforementioned cut-off low will continue to push north and east of the CWA through the day, as northwest flow aloft sets up on the backside of the low. At the surface, a reinforcement of high pressure will keep winds out of the north/northwest over the next 24-36 hours. Meanwhile, a weak coastal trough will keep clouds and rain chances along the immediate coastline and for the lower Texas coastal waters this afternoon and evening before weakening further on Friday.
A slow warming trend will commence, beginning today. Expect highs to reach the mid-upper 50s across the Northern Ranchlands and lower 60s across the Rio Grande Valley this afternoon. Today's temperatures will be highly dependent on cloud cover. If thick cloud cover persists longer than forecast, temperatures will likely not reach the 60s today and the forecast will have to be updated. Another abnormally chilly night is in store tonight, with lows dropping into the 40s again (lower 50s along the coast). On Friday, a short-wave ridge will produce subsidence over the region, producing more sunshine and warming temperatures into the mid-60s Friday afternoon across the CWA.
Long Term - SFriday Night through Wednesday
500 mb mid-level ridging building over the state into the weekend will yield to great weather featuring milder temperatures and mostly sunny to partly cloudy skies. A quick moving shortwave trough then dives across the state on Sunday bringing a weak cold front across the region during Sunday night into Monday morning. Model guidance remain in rather fair agreement indicating that little cold air advection is expected behind this front as temperatures stay around or just a few degrees cooler than Sunday. The front will lead to a slight chance for coastal showers Sunday night.
As the shortwave energy pushes to the east, 500 mb mid-level ridging develops across the state again into midweek. This will result in another warming trend with afternoon highs returning to near or even slightly above climatological normal. Expect for minimal rain chances midweek under mostly clear to partly cloudy skies. Winds remain generally light but a signal for strengthening onshore breezes is indicated for Wednesday afternoon in the model guidance.
Some moisture along with the approach of a cold front may be possible by end of next week but long-range model guidance diverge regarding the evolution of a cutoff low off Baja California.
Marine - Now through Friday
Marine conditions will gradually deteriorate late this morning, into this afternoon, and will continue into Friday due to reinforcing high pressure and weak coastal troughing. Northerly winds will increase by noon with small craft advisory conditions for both the Gulf waters and the Laguna Madre. On the Gulf waters, seas will rapidly increase to around 8 to 10 feet by this evening due to the strong northerly winds. Coastal troughing will also contribute to increased rain chances through Friday.
Friday night through Wednesday: Marine conditions will improve into the weekend as ridging develops over the region. A weak cold front moves across the region from Sunday night into Monday morning resulting in only a slight bump up in the wind speeds and seas on Monday. The marine conditions then become very favorable Tuesday into Wednesday morning. Onshore breezes will pickup in speed on Wednesday afternoon with seas slowly building. Winds could be enough for small craft to exercise caution during Wednesday afternoon.
NOAA Brownsville TX Office: Watches - Warnings - Advisories
TX...None. GM...Small Craft Advisory for winds from noon today to noon CST Friday for GMZ130-132-135.
Small Craft Advisory from noon today to noon CST Friday for GMZ150-155-170-175.