Quiet conditions will prevail today and tonight with cool temperatures tonight in St. Lawrence County.

Skies will be clear today and tonight with daytime highs in the mid 60s and lows mainly in the 40s but frost in the usually colder spots is a possibility with little wind, the NWS says.

There is a chance of showers beginning Tuesday afternoon, rising in the evening, and continuing into Wednesday and Wednesday night.

Highs will be near 70 Tuesday and lows at night are expected to be in the low 60s.

The temperature is expected to climb to the mid-70s Wednesday with lows that night in the mid 50s.

The NWS forecast for the St. Lawrence Valley and northwestern Adirondacks:

• Today: Sunny, with a high near 65. Light north wind.

• Tonight: Mostly clear, with a low around 42. Light and variable wind becoming east around 5 mph.

• Tuesday: A 30 percent chance of showers, mainly after 2pm. Increasing clouds, with a high near 69. South wind 3 to 6 mph. New precipitation amounts of less than a tenth of an inch possible.

• Tuesday Night: Showers, with thunderstorms also possible after 5am. Low around 62. Southwest wind 7 to 11 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.

• Wednesday: A chance of showers, with thunderstorms also possible after 1pm. Partly sunny, with a high near 76. Southwest wind 8 to 10 mph. Chance of precipitation is 50%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

• Wednesday Night: A 30 percent chance of showers. Mostly cloudy, with a low around 55. West wind around 5 mph becoming light and variable after midnight. New precipitation amounts of less than a tenth of an inch possible.

• Thursday: Partly sunny, with a high near 68. North wind 5 to 7 mph.

• Thursday Night: Partly cloudy, with a low around 50. East wind around 6 mph.

• Friday: Partly sunny, with a high near 72. Southeast wind 6 to 8 mph.

• Friday Night: Showers likely. Mostly cloudy, with a low around 61. South wind around 11 mph, with gusts as high as 22 mph. Chance of precipitation is 70%.

• Saturday: A 50 percent chance of showers. Mostly cloudy, with a high near 73. Southwest wind 11 to 13 mph, with gusts as high as 28 mph.

• Saturday Night: Partly cloudy, with a low around 53. Southwest wind 6 to 9 mph.

• Sunday: Mostly sunny, with a high near 73. West wind 5 to 7 mph.