Port Mansfield, TX to the Rio Grande River 20 - 60 NM Marine Forecast
|Tonight...East Winds 10 To 15 Knots Diminishing To 5 To 10 Knots After Midnight. Seas 3 To 5 Feet. Chance Of Showers And Thunderstorms.|
|Wednesday...East Winds 5 To 10 Knots. Seas 3 To 5 Feet. Chance Of Showers And Thunderstorms In The Morning, Then Slight Chance Of Showers And Thunderstorms In The Afternoon.|
|Wednesday Night...East Winds 5 To 10 Knots. Seas 3 To 5 Feet. Slight Chance Of Showers After Midnight.|
|Thursday...East Winds 5 To 10 Knots. Seas 3 To 5 Feet. Slight Chance Of Showers And Thunderstorms.|
|Thursday Night...East Winds 5 To 10 Knots. Seas 3 To 5 Feet.|
|Friday...Northeast Winds 5 To 10 Knots. Seas 3 To 5 Feet.|
|Friday Night...Northeast Winds 5 To 10 Knots. Seas 3 To 5 Feet.|
|Saturday...Northeast Winds 10 To 15 Knots. Seas 4 To 6 Feet With Occasional Seas Up To 7 Feet. Slight Chance Of Showers And Thunderstorms.|
|Saturday Night...Northeast Winds 5 To 10 Knots Shifting North After Midnight. Seas 6 To 8 Feet With Occasional Seas Up To 9 Feet. Slight Chance Of Showers And Thunderstorms.|
|Sunday...Northwest Winds 5 To 10 Knots. Seas 7 To 9 Feet With Occasional Seas Up To 10 Feet. Slight Chance Of Showers And Thunderstorms.|
|Sunday Night...South Winds 5 To 10 Knots Becoming Southwest 10 To 15 Knots After Midnight. Seas 5 To 7 Feet With Occasional Seas Up To 8 Feet. Chance Of Showers And Thunderstorms.|
| Area Forecast Discussion|
...UPDATED National Weather Service Brownsville TX
635pm CDT Tuesday Jun 2 2020
Short Term - Now through Wednesday night
Diurnally driven isolated showers and thunderstorms have developed across the mid- section of the forecast area this afternoon. This activity is not expected to be as widespread as yesterday, but will continue to move in a westward motion through the rest of the afternoon before dissipating out around sunset. Rainfall amounts will generally add up to a tenth to a quarter of an inch, but heavier pockets could drop up to an inch in some spots.
After a brief lull in rainfall activity this evening, isolated showers are expected to develop again sometime around midnight as a weak surface coastal trough develops overnight tonight. Short-range deterministic models and CAMs indicate highest chances, albeit around 20-30%, of precipitation will initially be along the coast early Wednesday morning, then spread inland through the morning. Showers and thunderstorms look to remain isolated and generally light in nature, but may flair up some late in the morning and into the afternoon as diurnal heating and a seabreeze occur.
As a weak mid/upper-level low lifts northward out of Texas tonight, ridging over northwest Mexico/southwest U.S. will begin to gradually slide eastward over western Texas, starting a warming trend across Deep South Texas, with majority of the area reaching the low-mid 90s tomorrow afternoon, mid-upper 80s along the coast.
Long Term - Thursday through Tuesday
500mb high pressure will begin to dominate the region as it builds from the west over Northern Mexico and stretches across West Texas. Dry, subsident northerly flow in the mid to upper levels will suppress deep moisture and overall rain chances. However, model time heigheights maintain decent low-level moisture with relative humidity values of 40 to 60% up to 700mb. This should be sufficient for at least isolated seabreeze activity each day with light easterly surface flow. As even drier air begins to mix down towards the surface late in the period, temperatures will gradually heat up each day. Highs may reach well into the 90s across most inland locations and above 100F late in the weekend across the Upper Rio Grande Valley. We will need to monitor for possible Heat Advisories due to high dew point values and hot ambient temperatures.
All eyes are on Tropical Storm Cristobal, which was named just this morning in the Southern Bay of Campeche. The National Hurricane Center has its five-day cone going generally northward towards the South Central Gulf. No impacts are expected to Deep South Texas or the lower Texas coast through at least Thursday. There is still considerable uncertainty with its exact track, however, we may start to see increasing swells this weekend and especially early next week. This would potentially lead to coastal flooding, high surf and dangerous rip currents. We will continue to closely monitor the latest model guidance and update as the system progresses.
Marine - Now through Wednesday night
Not too many changes made from the previous marine discussion. Broad high pressure across the eastern Gulf and a weak surface trough over the lower Texas coast will continue to produce generally light to moderate east to east- northeast winds through the period. Seas will gradually build to 3 to 5 feet beginning overnight tonight with persistent easterly winds and easterly swell. While showers and thunderstorms will continue to be possible tonight and tomorrow, they should only be isolated in nature through the short-term period.
Thursday through Tuesday: Weak surface high pressure over the Northeast Gulf and Tropical Storm Cristobal well to the south over the Bay of Campeche will maintain generally light easterly flow through this weekend. This will lead to low to moderate seas across the lower Texas Gulf waters. There is uncertainty with the exact track of Tropical Storm Cristobal, but we may start to see increasing swells this weekend and especially into early next week. This would lead to increasing seas and potentially hazardous marine conditions Saturday night through early next week.
NOAA Brownsville TX Office: Watches - Warnings - Advisories