Saturday, January 21, 2012

Forecast for Sunday, January 22, 2012

At mid-afternoon, areas that had temperatures at or just below freezing have slid back a few degrees in the wake of colder air behind the departing low pressure area. Areas that had risen a few degrees above 32 are also now dropping below the freezing mark. The result has been to take slushy and wet surfaces and cause them to freeze up, if they hadn’t already been a sheet of ice due to freezing rain. In some areas, freezing drizzle continues to add a light coating of ice with each passing hour.

The difficulty tonight is to determine if and when the misting will shut off. There is some suggestion that moisture remains trapped at lower levels and areas of fog and mist continue, despite gradual clearing above the surface. We have been watching drier air attempting at puncturing into Philadelphia. The RPM model does hint at clearing, but may not be detecting the potential fog. Either way, it will be slippery and treacherous.

Sunday will be mostly cloudy, with possible intervals of sunshine. Modeling has come in colder for Sunday Night into early Monday as warm air overrides the colder in place, allowing for overrunning precipitation to develop. This means that while light, some areas could deal with freezing drizzle or light freezing rain. Temperatures will result in a close call again. Some sleet pellets are also possible. Snow would be limited to Mount Pocono. The region will enter the warm sector on Monday and if the warm front moves as far north as indicated, temperatures could be in the range of 55 to 60 in the city. Sometimes, these fronts can get stuck and temperatures bust.

A thunderstorm is possible on Monday Night with the front!