Freeport to Matagorda Ship Channel, TX Marine Forecast
|This Afternoon...Southeast Winds Around 10 Knots. Seas Around 2 Feet.|
|Tonight...South Winds 10 To 15 Knots. Seas 2 To 4 Feet. A Slight Chance Of Showers After Midnight.|
|Friday...South Winds 10 To 15 Knots. Seas 3 To 5 Feet. A Chance Of Showers.|
|Friday Night...South Winds 10 To 15 Knots. Seas 3 To 5 Feet.|
|Saturday...Southwest Winds 10 To 15 Knots. Seas 3 To 5 Feet. A Chance Of Showers And Thunderstorms In The Afternoon.|
|Saturday Night...Northwest Winds 25 To 30 Knots, Becoming North 30 To 35 Knots After Midnight. Seas 3 To 5 Feet. A Chance Of Showers And Thunderstorms In The Evening.|
|Sunday...North Winds 30 To 35 Knots, Diminishing To Around 20 Knots In The Afternoon. Seas 3 To 5 Feet.|
|Sunday Night...North Winds 10 To 15 Knots, Becoming Northeast Around 10 Knots After Midnight. Seas 2 To 3 Feet.|
|Monday...East Winds Around 10 Knots. Seas Around 2 Feet.|
|Monday Night...Southeast Winds 10 To 15 Knots. Seas Around 2 Feet. Winds And Seas Higher In And Near Thunderstorms.|
| Area Forecast Discussion|
National Weather Service Houston/Galveston TX
1142am CST Thu Dec 7 2023
(Saturday through Wednesday) Issued at 312am CST Thu Dec 7 2023
Going into Saturday, the surface low that subsequently develops from a mid/upper trough sweeping through the Central CONUS will be moving quickly to the NNE into the Great Lakes region as it rides along the upper level wind pattern. Since the movement of this low is more northerly than easterly, the associated cold front will take a bit longer to push through. Think of it as the front gets caught in traffic coming down I-45...I'm sure we all can relate. Model consensus (including some high-res guidance) points toward a mid to late afternoon FROPA for most. It's too early to give a super precise timeframe, but in general it's looking like the front begins to move into the Brazos Valley around 1-4pm and doesn't push offshore till around or after 9pm.
There remains "some" potential for strong to severe storms to develop along and ahead of the frontal boundary given the abundance of shear (0-6km shear greater than 60 kts) and an axis of instability (MUCAPE 1200-1800 J/kg) within the warm sector of the surface low...but there's something that will likely hinder our chances of seeing these stronger storms. With an 850mb high off to our east providing southwesterly flow throughout most of the week ahead of the approaching front, a fairly robust subsidence inversion layer (cap) will be in place around 850-750mb. Check out some of the forecast soundings and you'll see it's fairly sharp...so that'll be tough for storms to overcome. That's not to say that storms can't break the cap...but the odds look to be more in favor of the cap holding. All that being said, Storm Prediction Center has kept parts of Southeast TX in a marginal to slight risk of severe weather on Saturday. Generally, areas along and east of I-45 are in the slight risk...but the best chance of seeing strong to severe storms will likely be in the Piney s (northeast counties). Confidence in rainfall in general occuring is fairly high though, and some locally heavy rain will be possible as well along the front with PW values (Precipitable Water values) surging up to 1.4"-1.6" (90th percentile: ~1.44"). There are no concerns for flooding.
With the cold front now moving through more in the mid to late afternoon time frame, that allows more time for southwesterly winds ahead of the front and compressional heating to get temperatures into the mid to upper 70s on Saturday afternoon. Some areas may even reach the 80°F mark...that'll make the 12 hour temperature difference that much more drastic. Behind the front, strong Cold Air Advection will prevail with northwesterly winds around 20-25 mph and gusts of 30-35 mph. A Wind Advisory may be needed for parts of Southeast TX Saturday evening into Sunday morning. So, if you have any outdoor holiday decorations up (especially inflatables), you'll definitely want to make sure they are secured...it is the season of giving but let's not give accidental decoration donations to your neighbors down the street. PW values (Precipitable Water values) drop sharply behind the front reaching less than 0.2" by Saturday night, which is near the climatological minimum. Gusty winds overnight will keep temperatures from dropping as much as they could...but we'll still see a 30-40°F drop from Saturday afternoon with lows in the upper 30s to low 40s.
Surface high pressure moves overhead on Sunday as daytime highs only climb into the mid to upper 50s. With clear skies and light winds overnight on Sunday, we have the perfect recipe for maximum radiational cooling...so I nudged temperatures down a bit below guidance. Expecting widespread low temperatures in the 30s with parts of the Brazos Valley/Piney s experiencing a light freeze. With a 850mb high remaining overhead into Tuesday, 850mb temperatures remain around the 10th percentile. So, although high temperatures will increase...they'll only increase to the low to mid 60s. Surface high pressure slides off to the east by Tuesday leading to return flow increasing PW values (Precipitable Water values) back to 1.0"-1.3" off the coast by Tuesday night. That leads to rain chances returning generally south of I-10. Midweek looks rather...interesting to say the least. Another mid/upper level trough moves from the NW CONUS down towards the Four Corners on Tuesday. There is model consensus on this becoming a cutoff upper level low that remains in the SW CONUS past midweek. If you read last night's AFD then you'll remember that there was talk of a potential midweek cold front...well that would be postponed in this scenario if it verifies. This is a good example of why we don't set things in stone a week out...each model run could (and likely will) show something different at that range! The good news is that model guidance has been very consistent on keeping temperatures generally in the 60s for highs and the 40s for lows into next week.
Issued at 312am CST Thu Dec 7 2023
Onshore flow returns later this morning and begins to strengthen going into tonight and Friday as the next weather system approaches. Winds may reach the caution threshold as early as tonight and will be fairly close to the advisory threshold Friday afternoon into Friday night. As a result of the strengthened onshore flow, the risk of rip currents will also be elevated on Friday. A strong cold front will push through the waters late Saturday with moderate to strong northwesterly winds in its wake. Mariners can expect at least a Small Craft Advisory to be in effect from Saturday evening into Sunday morning. Wind gusts to gale force will be possible in the Gulf waters. Due to the elevated offshore flow, low water levels will be possible in the bays during low tide on Sunday morning. Wave heigheights also increase due to the strong offshore flow and peak in the 7-9 foot range on Saturday night/Sunday morning. Winds and seas gradually subside on Sunday with onshore flow returning by Monday afternoon.
NOAA Houston/Galveston TX Office: Watches - Warnings - Advisories