New Orleans' annual Carnival season got off to a rough start Friday when thunderstorms and chilly temperatures canceled or postponed all but one parade in the city and surrounding towns and suburbs.

About 50 others will roll over the next 12 days, culminating on Mardi Gras, or Fat Tuesday, the season's raucous pre-Lenten climax which falls this year on Feb. 5.

Rain showers were likely Saturday morning but forecasts said the chance of rain should decrease by the afternoon and temperatures — in the low 40s Friday night — were expected to be in the upper 50s on Saturday.

Click here for photos.

Friday's New Orleans parades were being staged by the clubs (known here as "krewes") of Oshun and Pygmalion. Oshun rolled despite the rain, but Pygmalion rescheduled its romp through the streets for Wednesday. The parades scheduled in suburban Jefferson Parish and on the north shore of Lake Pontchartrain were also postponed.

The Krewe of Cork's annual foot parade through the city's French Quarter was held prior to Friday's rain storm. The krewe's members don wine- and grape-related costumes and culminate their day of "wine, food and fun" with a King and Queen's party, krewe officials said.

The biggest parades — among them Endymion, Bacchus, Orpheus, Rex and Zulu — will take place during the season's final four days. Some will feature celebrity riders, including movie star Kevin Costner, who is scheduled to ride in Endymion on Friday, Feb. 2.

In the last extensive economic study of Mardi Gras — performed for the 2000 season by the University of New Orleans — the total impact was pegged at $1.05 billion. In 2006, just six months after Katrina flooded most of the city, the crowd was down from the usual 1 million visitors to about 350,000, with local residents doing most of the celebrating, according to UNO.

An estimated 800,000 participated last year.

One factor that could influence the number of visitors this year is timing. The season is pegged to the arrival of Ash Wednesday and Easter, which vary from year to year. This year, Ash Wednesday is Feb. 6, making for one of the earliest Mardi Gras seasons possible. That often means the peak of the season does not coincide with college spring breaks and that weather is likely to be colder, discouraging visitors.