Super fog is returning to New Orleans area over Halloween weekend. What to know

Super fog is expected to return this weekend as Halloween activities and events are ramping up and people are planning to be out and about on the roads. 

The National Weather Service in Slidell is advising people to avoid driving overnight and in the early morning on Saturday and Sunday. 

Dense fog mixed with smoke from nearby swamp and marsh fires dropped visibility so low Monday morning that there were pileups of over 150 vehicles on the raised portion of Interstate 55 that runs between Lake Pontchartrain and Lake Maurepas. Seven people are confirmed dead so far, and 68 injured. 

A dense fog advisory has been issued from 10 p.m. Friday to 9 a.m. Saturday, and it’s possible one will be needed for Sunday. 

The advisory covers the entire New Orleans, Baton Rouge, Hammond and Slidell areas, including Hancock and Pearl River counties in Mississippi. 

Typically, fog advisories are issued very early in the morning the same day fog is expected. But with the super fog, forecasters are trying to stay a step ahead. 

“We’re definitely being extra cautious based on what happened,” said Mike Efferson, weather service meteorologist.

Strong winds have kept the smoke and fog at bay since the crash. But they’re slowing to 5-10 mph over the weekend which will allow fog to develop. The winds are coming from the southeast, which will blow smoke from the Lafitte and Bayou Sauvage fires over New Orleans and toward Baton Rouge. 

The super fog could be especially in areas near water that see less wind, such as along the Causeway Bridge, I-55 and parts of New Orleans East. 

“… Smoke will locally reduce visibility to near 0, so be mindful of that,” the weather service forecast discussion says. 

It’s best to wait to drive until the fog has burned off later in the morning, Efferson said. 

Cold front coming

After near-record warm temperatures this week — Monday tied the record high of 87 from 1995 — a cool-down is coming for the actual holiday. 

On Halloween day, the high may only reach 65 degrees, and temperatures are expected to drop to a low of 47 that night. 

There could even be freeze concerns in southwest Mississippi, the weather service said.

Unfortunately, the front won’t bring any rain that could help put out the fires and help with the exceptional level of drought across most of the state. 

Louisiana is on track to have the driest year yet if we don’t get a foot of rain before the end of 2023, Efferson said. 

New Orleans forecast

Saturday: Sunny, with a high near 83. East wind 5-10 mph.

Saturday night: Mostly clear, with a low around 69. East wind 5-10 mph.

Sunday: Sunny, with a high near 84. Southeast wind 5-10 mph.

Sunday night: Mostly clear, with a low around 69. Southeast wind around 5 mph.

Monday: Mostly sunny, with a high near 82. North wind 5-10 mph.

Monday night: Partly cloudy, with a low around 57. North wind 10-15 mph.

Tuesday: Mostly sunny, with a high near 65. North wind around 15 mph.

Tuesday night: Partly cloudy, with a low around 47. North wind around 15 mph.

Wednesday: Sunny, with a high near 62. North wind around 15 mph.

Wednesday night: Mostly clear, with a low around 46. Northeast wind 10-15 mph.

Thursday: Sunny, with a high near 65. Northeast wind 10-15 mph.