Overview
- Forecasts call for dense fog early Thursday with WGAL naming 4 a.m. to 10 a.m. an Impact Morning and visibility possibly falling to a quarter‑mile or less, which could slow the morning commute.
- Model guidance including the GRAF shows the fog will be most widespread in suburban and rural areas outside city cores rather than over downtowns.
- Meteorologists warned that authorities may issue a formal dense fog advisory and urged drivers to use low‑beam headlights, allow extra travel time, reduce speed, and increase following distance.
- Expect clearing during mid‑ to late‑morning with sunshine returning and afternoon highs near 70 degrees, then a dry cold front arriving Friday for continued pleasant weather.
- Fog forms because clear skies and overnight cooling into the mid‑40s allow near‑surface air to saturate, and this can disrupt school buses, commutes, and early errands so plan for delays and slower traffic.