DELMARVA - Drivers in Sussex County and Delaware’s coastal beach towns should plan for near-zero visibility late Tuesday evening into early Wednesday as a Dense Fog Advisory takes effect through Wednesday morning.
Expect fog to become widespread overnight, with computer guidance showing a high chance of visibilities dropping below 1/4 mile at times. The fog is being fueled by moist, milder air flowing in off the Atlantic and sliding over colder ground, a setup that often traps moisture near the surface and thickens fog quickly.
Even after the densest fog lifts Wednesday morning, low clouds and lingering fog are expected to hang on for a time, especially near waterways and along coastal routes in places like Lewes, Rehoboth Beach, Dewey Beach, Bethany Beach and Fenwick Island.
Rain is expected to develop Wednesday afternoon as a warm front lifts north, then taper off later Wednesday evening. Patchy fog could redevelop Wednesday night after the rain ends.
What you can do (and why it works):
When fog is dense, the biggest danger is that your stopping distance becomes longer than what you can see. Slow down, use low-beam headlights (high beams reflect back off fog droplets), leave extra space, and be ready for sudden changes in visibility on bridges, causeways and low-lying roads near the bays and ocean. If you’re walking or biking near traffic, wear reflective gear so drivers can spot you sooner.
Looking ahead, Thursday turns cooler behind a backdoor cold front, and additional rain chances are expected later in the week, with longer-range guidance also hinting at a potential winter storm Sunday followed by much colder air early next week.