MIAMI — Tropical Storm Bertha is weakening as it tracks westward along the northern Gulf Coast with maximum sustained winds of 50 mph, prompting the National Hurricane Center to discontinue the tropical storm warning for portions of the Florida Panhandle east of the Okaloosa/Walton County line.

The storm was located about 165 miles west-southwest of Panama City and roughly 50 miles east-northeast of the mouth of the Mississippi River as of the 4 a.m. CDT advisory issued by NHC Forecaster Papin. Bertha is moving due west at 5 mph with a minimum central pressure of 998 mb, or 29.47 inches. Tropical-storm-force winds extend outward up to 105 miles from the center.

A tropical storm warning remains in effect from the Okaloosa/Walton County line in Florida westward to Morgan City, Louisiana, including metropolitan New Orleans and Lake Pontchartrain. A tropical storm watch extends from west of Morgan City to Cameron, Louisiana, and includes Lake Maurepas. Tropical storm conditions are expected to continue spreading across portions of the northern Gulf Coast within the warning area, with conditions possible in the Louisiana watch area by tonight.

An Air Force Reserve reconnaissance mission found peak flight-level winds of 47 knots and confirmed the minimum central pressure had risen slightly to 998 mb. A dropsonde launched on the southeast side of the circulation measured a 500-meter layer mean wind of 54 knots, though a standard reduction from that altitude yielded a slightly reduced intensity estimate of 45 knots. The NHC discussion noted the storm’s appearance “has gone downhill,” with the deepest convective activity separating further south from the low-level circulation, which is “now mostly exposed offshore of the coast of Alabama.”

A wind gust of 49 mph was reported at the Orange Beach Buoy offshore of the Alabama coastline. An elevated oil platform located well offshore in the Mississippi Canyon reported a sustained wind of 45 mph with a gust up to 56 mph.

The primary steering feature driving Bertha’s motion is a mid-level ridge that has been sliding eastward from the southern Plains to a position north of the tropical storm. That configuration should keep Bertha on a westward heading over the next 24 to 36 hours, though the NHC noted that sheared bursts of deep convection forming south of the center could tug the storm southward. Some hurricane-regional models depict the possibility of a new center reforming under those convective bursts in the 24-to-36-hour window, though the official NHC track forecast does not reflect that scenario.

Northeasterly vertical wind shear of 25 to 30 knots, combined with land interaction, is expected to produce gradual weakening over the next several days. The NHC track forecast is positioned roughly between the latest Google DeepMind and HFIP Corrected Consensus model solutions.

Storm surge remains a concern along the immediate coast. The combination of surge and tide could push water 2 to 4 feet above ground from the mouth of the Mississippi River to the Mississippi-Alabama border. Areas from Cameron, Louisiana, to the mouth of the Mississippi, and from the Mississippi-Alabama border to the Okaloosa/Walton County line in Florida, could see 1 to 3 feet of surge. Lake Pontchartrain faces a similar 1-to-3-foot surge threat.

Bertha is expected to produce total rainfall of 1 to 4 inches, with isolated totals up to 6 inches, along the central to western Gulf Coast from western Florida to southern Texas through Thursday. The NHC warned that rainfall may produce isolated flash flooding, especially in urban areas. Life-threatening surf and rip current conditions are expected to continue spreading westward along the northern Gulf Coast over the next few days.

The next intermediate advisory from the National Hurricane Center is scheduled for 7 a.m. CDT, with the next complete advisory at 10 a.m. CDT.