Tropical Storm Francine forms; track jogs eastward again

Tropical Storm Francine has formed in the Gulf of Mexico.

The National Hurricane Center announced in its 10 a.m. CDT advisory that the storm's center of circulation has formed, resulting in the upgrade.

As of 1 p.m., Francine's maximum sustained winds had intensified to 60 miles per hour. The storm's eye is moving north-northwest at five miles per hour and has a minimum central pressure of 996 millibars.

A hurricane watch is now posted for the Louisiana Gulf Coast between Cameron and Grand Isle. A tropical storm watch is in effect from Cameron to High Island, Texas, and from Grand Isle to the mouth of the Pearl River, including Lake Pontchartrain and Lake Maurepas. A storm surge watch is in effect from High Island, Texas, to the Mississippi/Alabama state line, including Vermilion Bay, Lake Pontchartrain, and Lake Maurepas.

Francine's cone of uncertainty has shifted eastward again, with the 10 a.m. update predicting landfall in the western portion of Vermilion Bay near Marsh Island, just south of Abbeville and New Iberia. The update track shows Francine taking a more northeasterly track through Louisiana before crossing into Mississippi as a tropical storm.

National Hurricane Center forecasters admit that forecasting Francine's movement is difficult.

"The estimated motion is still tricky given the center only recently formed but is estimated still off to the north-northwest at 340/4 kt," forecasters said in their latest forecast discussion. "The system is expected to gradually turn northward and then north-northeastward as it moves between a mid-level ridge centered over Cuba and a broad mid- to upper-level trough located to its northwest over Texas. The guidance this cycle has shifted a little eastward and faster, and the NHC track forecast was once again nudged in that direction."

The forecasters also note that the current track "splits the difference" between two models and "still shows Francine moving ashore of Louisiana sometime on Wednesday evening."

Flash flooding and damaging winds are expected across south Louisiana when Francine comes ashore. Residents are urged to prepare for a worst-case scenario, especially if rapid intensification happens prior to landfall.