As a warm front approaches in the early morning hours, rain and areas of drizzle will develop across the region. However, temperatures in some areas at the surface will be at or below freezing when the rain begins to fall allowing for the potential of freezing rain. The Lehigh Valley, Poconos, North-Central New Jersey, Lancaster, and the North and Western suburbs have the best shot at observing at least an hour or two of icing. Even a trace of ice can cause hazardous road conditions. So the morning commute could be very slow and slick. The transition from freezing rain to rain is expected to occur during the morning commute south of the Lehigh Valley and the Poconos. It may not changeover to liquid rain in the Poconos until early afternoon.
With warmer air riding over a cold ground and in some areas a snow pack, fog will probably develop. Some of the fog may be dense.
After the soaking rain the other day for most areas, followed by the snow, areas with a melting snowpack could experience areas of poor drainage flooding with a 0.25” to 0.50” of new rain expected. Also, drains may be blocked by the snow.
Temperatures remain tricky for Monday. The warm front may slow considerably when it begins to encounter the areas with the snowpack and the higher terrain. MOS guidance continues to show Philadelphia International Airport making it into the fifties. It is possible here given that only 1.4 inches of snow fell the other day. Areas north of here may be stuck in the forties where the snow depth is considerably greater. There is a bust potential here, especially with low clouds and fog expected. A cold front sweeps in later on Monday Night. Blustery conditions are expected to follow for Tuesday.
We continue to watch a potential system for Wednesday Evening into Thursday Morning. This system may be a glancing blow or perhaps something more significant. The models continue to not by in agreement on the track and intensity. Rain, sleet, and wet snow is possible should we see precipitation. Another potential system may impact us next weekend.