Marine Weather Net

Vermilion Bay Marine Forecast


TODAY

SW
WINDS
5 - 10
KNOTS

TONIGHT

N
WINDS
15 - 20
KNOTS

TUESDAY

N
WINDS
15 - 20
KNOTS

TUESDAY NIGHT

N
WINDS
10 - 15
KNOTS

The Marine Weather Forecast In Detail:
GMZ435 Forecast Issued: 355 AM CDT Mon Sep 28 2020

SMALL CRAFT EXERCISE CAUTION IN EFFECT FROM 1 PM CDT THIS AFTERNOON THROUGH TUESDAY AFTERNOON
Today...Southwest Winds 5 To 10 Knots Becoming Northwest 15 To 20 Knots In The Afternoon. Bay Waters A Light Chop Increasing To Rough In The Afternoon. Chance Of Showers And Slight Chance Of Thunderstorms In The Morning, Then Showers And Thunderstorms Likely In The Afternoon.
Tonight...North Winds 15 To 20 Knots. Bay Waters Rough. Slight Chance Of Showers In The Evening.
Tuesday...North Winds 15 To 20 Knots. Bay Waters Rough.
Tuesday Night...North Winds 10 To 15 Knots. Bay Waters Choppy.
Wednesday...North Winds 5 To 10 Knots. Bay Waters A Light Chop.
Wednesday Night...Northwest Winds Around 5 Knots. Bay Waters Smooth.
Thursday...Northwest Winds Up To 5 Knots. Bay Waters Smooth.
Thursday Night...North Winds 5 To 10 Knots. Bay Waters A Light Chop.
Friday...Northeast Winds 10 To 15 Knots. Bay Waters Choppy.
Friday Night...Northeast Winds 10 To 15 Knots. Bay Waters Choppy.
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Synopsis for Lower Atchafalaya River LA to High Island TX out 60 NM including Sabine and Calcasieu Lakes and Vermilion Bay: GMZ400
355 AM CDT Mon Sep 28 2020

Light onshore flow will shift northwesterly and rapidly strengthen in the wake of a cold front moving through the region today. Strong northerly winds and rough seas will continue tonight into Tuesday morning. Offshore flow will diminish Tuesday night as high pressure builds over the area.
Area Forecast Discussion
National Weather Service Lake Charles LA
443am CDT Monday September 28 2020

Synopsis
Latest UA analysis and satellite imagery shows shortwave energy diving south across the plains, deepening a mid level trough over the cntl CONUS and helping to propel a cold front toward the area. As of 4 AM, the front extends from roughly El Dorado AR to College Station TX. Ahead of front, southerly winds continue to transport warm and moist air into the region. Temperatures are currently in the middle to upper 70s across much of the area with dewpoints at or just a degree or two lower than the air temps. Satellite imagery and surface observations indicated widespread low clouds and patchy fog have developed across the area.

A cluster of showers and storms, including a few strong storms, have been developing along the front as it encounters the warm and modestly buoyant airmass. Additional convection continues to develop further south along the boundary, with a few of these storms moving into the Lakes Region of SE TX.

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The front is expected to enter our NW zones at the start of the forecast period this morning, then quickly sweep across the area through the day, exiting south cntl LA by late this afternoon. Southerly winds will allow moisture to pool ahead of the boundary, with precipitation water values climbing to near 2 inches in the vcnty of the front. Frontal convergence will be the primary forcing mechanism for convective development, with sctd to nmrs showers forming along and behind the boundary as it crosses the area. Elevated instability atop the post frontal airmass should be enough for a few thunderstorms to develop with the shower activity. Ahead of the front, daytime heating will contribute to CAPE values reaching between 2000-2500 J/kg across portions of southern LA, allowing for storms to become a little more widespread. However the potential for any strong to severe storms will be limited due to weak shear and marginal lapse rates.

Much cooler and drier weather will follow the front tonight into Wednesday. Temperatures the next couple of nigheights will be ~8 to 12 degrees below normal, with lows in the 50s both nights. The coolest temps can be expected Wednesday morning, with lows near 50 north and in the lower to middle 50s south. Aftn temperatures will also run below normal with highs in the 70s Tuesday, and into the upper 70s/around 80 Wednesday.

An amplified pattern aloft will persist through the workweek as a series of shortwaves moving south out of Canada maintain a deep trough over the eastern CONUS, with a ridge over the western states. This will keep a dry northwesterly flow over the region. Temperatures will warmup slightly by Thursday as the initial surface high slides south and east ahead of another front. A reinforcement of cool high pressure will follow this front. No rain is expected as dry air will remain entrenched across the area.

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Marine
Onshore flow will shift northwesterly and increase sharply in the wake of a cold front today. A much cooler and drier airmass spreading over the warm nearshore waters will produce strong winds and rough seas this afternoon through Tues morning, with Small Craft Advisories in effect. Sctd showers and a few tstms will also accompany the front as it crosses the coastal waters today.

Offshore flow will diminish Tuesday, with a light to moderate offshore flow persisting through much of the period. Winds and seas will briefly increase Friday in the wake of a secondary reinforcing front.

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NOAA Lake Charles LA Office: Watches - Warnings - Advisories
LA...None. TX...None. GM...Small Craft Advisory from 1pm this afternoon to 1pm CDT Tuesday for GMZ450-452-455-470-472-475.

Small Craft Exercise Caution from 1pm CDT this afternoon through Tuesday afternoon for GMZ430-432-435.