Thick fog blanketing the region this morning and the potential for heavy rain this afternoon pose a double-whammy to an already-challenging day on the roads in southwestern Connecticut in the wake of Friday's train collision in Bridgeport.

Fog throughout the area -- some dangerously dense -- early today is adding an extra note of frustration to the morning commute, but the National Weather Service says it should dissipate by later morning.

The daytime high temperature will rise to the mid-70s under cloudy skies, with the threat of rain -- and possibly thunderstorms -- after 1 p.m. There will be a southwest wind 5 to 9 mph. Odds of daytime precipitation are 30 percent, the NWS says.

Tonight, there remains a chance of showers and thunderstorms, and fog is expected to settle in parts of the region again. The temperature will drop to a low of about 60 degrees, with a south wind 5 to 9 mph. Chance of nighttime precipitation is 30 percent.

Tomorrow, there is a slight chance of showers and possibly thunderstorms, after 1 p.m. Otherwise, skies should be partly sunny, with a high temperature in the low-70s. Chance of precipitation is 30 percent.

There is a 40 percent chance of precipitation tomorrow night, as the temperature readings hit a low of about 60 degrees.

On Wednesday, there is another 40 percent chance of showers and thunderstorms, and the temperature rises to high of nearly 80 degrees. Nighttime also could see showers and thunderstorms, mainly before 10 p.m.

The outlook for Thursday, according to the weather service, is cloudy, possible showers and temperatures in the 70s.