Marine Weather and Tide Forecast for Lamar, TX

DISCUSSION
Issued at 200 AM CDT Sat Apr 18 2026

Big changes are right around the corner as we head into Saturday. A strong cold front is working its way south through Texas and will move into the forecast area by around mid-day. The front will progress quickly southward bringing a sharp drop in temperatures and gusty north to northeast winds. Temperatures will warm into the 80s in the morning before dropping into the 60s post-front. Ahead of the front moisture is confined to the lowest layers of the atmosphere (below 850mb) and this will limit convection in the pre- frontal environment. Deeper moisture will arrive with the front though and bing scattered showers and a few elevated thunderstorms to the area Saturday afternoon and especially Saturday night. PWAT values are progged as high as 1.8, which is a step up from earlier model runs. Rainfall purely associated with the front through Sunday will generally be under half an inch for much of the area, but could be closer to an inch west.

Equally as interesting as the approaching front is the environment behind the front with a good set up for continued beneficial rain into the early part of next week. A coastal trough, isentropic lift thanks to the shallow nature of the front, plus upper level shortwaves make Monday and Tuesday rainfall chances look promising.
While most of the time an isentropic pattern provides light showers, the addition of the mid-level energy should give us some moderate showers mixed into that. An additional inch of rain is possible over eastern areas with this isentropic pattern, with lower amounts west.
Overall a solid chance of an area wide 1-1.5 inch rain total through the next 4 days, with high end totals in a few locations above 2 inches. The best chance for the higher totals would be in the northern Coastal Plains where positioning of the isentropic flow plus mid-level energy matches up best.

While the rain is the big news everyone is interested in, the temperatures Sunday are a notable topic as well as we'll be 10 to possibly as much as 20 degrees below normal across the area. Have gone below NBM guidance, trending toward cooler end with all the signs of a shallow cold airmass stuck in place under warmer air above and a thick cloud cover. NAM guidance, as is typical, is the lower, suggesting a non-zero chance that some areas don't make it out of the 50s. NBM currently giving about 20% chance for Laredo to not top 60, and considering the normal high there right now is 89, this would be substantial. In fact, the coolest high on record there for Sunday is 70, and there is a high potential we don't see that.

Gradually warming conditions are expected as we head through next week with drying conditions after Wednesday.

AVIATION
(06Z TAFS)
Issued at 200 AM CDT Sat Apr 18 2026

MVFR CIGs are expected to redevelop overnight and persist through much of Saturday morning as low-level moisture remains in place with continued southeasterly flow. Some improvement to VFR is briefly possible Saturday afternoon before the approaching front. This front will move from north to south across the region Saturday afternoon into the evening (between 18-00Z). Expect a sharp wind shift to the north-northeast with increasing speeds and gusts potentially reaching 25-30 knots immediately behind the boundary. CIGs are expected to lower again to MVFR along and behind the front with the scattered showers and storms that will develop. PROB30 groups for thunderstorms have been included at all sites late in the TAF period to denote IFR conditons, reduced VSBYs, and increased wind gusts in and around any storms.

MARINE
Issued at 200 AM CDT Sat Apr 18 2026

A small craft advisory remains in effect through early this morning. Another small craft advisory will then be issued for the post frontal environment Saturday night and Sunday. Strong northeasterly winds will develop with a few gusts to gale force especially in farther offshore waters. Rain chances will also increase behind the front and persist through the first half of the week. Winds will subside early next week shifting from east to southeast.

FIRE WEATHER
Issued at 200 AM CDT Sat Apr 18 2026

Rain chances return this weekend with the passage of a cold front Saturday afternoon. Wetting rains are possible with an area wide average near an inch of rain currently expected this weekend through the first half of the upcoming week. Expect windy conditions behind the front, and this will persist through Sunday along the immediate coast. Winds behind the front will be mainly northeast, with no real offshore flow anticipated. Conditions become drier and warmer by mid-week.

PRELIMINARY POINT TEMPS/POPS
Corpus Christi 84 61 70 63 / 20 50 30 50 Victoria 84 55 71 56 / 50 70 10 20 Laredo 89 56 63 58 / 40 80 60 50 Alice 88 58 70 59 / 30 60 40 50 Rockport 84 61 75 65 / 20 60 20 40 Cotulla 82 56 66 58 / 40 70 30 40 Kingsville 87 59 69 61 / 20 60 40 50 Navy Corpus 81 64 72 67 / 10 50 40 50

CRP WATCHES/WARNINGS/ADVISORIES
TX...None.
GM...Small Craft Advisory from midnight tonight to midnight CDT Sunday night for GMZ231-232-236-237-250-255-270-275.