A Dense Fog Advisory will be in effect from 10 p.m. Tuesday until 11 a.m. Wednesday across all of southeast Louisiana and southwest Mississippi. Commuters and last-minute travelers should consider allowing extra time to drive to their destinations during this timeframe. When driving in fog, slow down, use low-beam headlights, and leave extra following distance. Widespread dense fog with visibility of a quarter mile or less appears likely on the morning of Christmas Eve.

Christmas Eve & Day: The signal for fog doesn’t get much more obvious. All the ingredients are in place for widespread dense fog on both Christmas Eve morning and Christmas morning. Mornings will be very mild, with lows sitting in the upper 50s to perhaps the low 60s. Particularly on the night of Christmas Eve, extra caution is urged in St. James and St. John the Baptist Parishes. With bonfires being lit along the levee, smoke trapped near the ground may mix with fog overnight, creating what’s known as “super fog.” This can drop visibility to near zero. With crowds out lighting the way for Papa Noel, local travel could become hazardous, so be vigilant on the roads.

Given the setup, low clouds and fog may be slow to clear even with daytime warming. This could substantially limit afternoon highs. The latest Storm Station forecast reflects this, with highs trimmed back into the mid-70s both days, assuming at least some sunshine breaks through.

Up Next: Warm temperatures and foggy mornings appear to carry over into the weekend, but that pattern will abruptly end late Sunday with the arrival of a strong cold front. A few quick showers may accompany the front. Much colder air will follow, with highs plunging into the 50s early next week. Morning lows could dip below freezing as early as Tuesday morning.