Mainly sunny and dry conditions will prevail today with high pressure building across the North Country, but clouds are expected to move in overnight bringing a chance of some snow showers across St. Lawrence County Tuesday afternoon and evening.

Highs today are expected to reach the mid 20s today to near 30 Tuesday, with overnight lows in the teens, according to forecasters.

A gradual warming trend is expected toward the end of the week, and the possibility of significant precipitation – rain or snow -- is looking likely for next weekend, the National Weather Service predicts.

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

• Today: Partly sunny, with a high near 24. Light and variable wind becoming west around 6 mph.

• Tonight: Mostly cloudy, with a low around 13. Light south wind.

• Tuesday: A 40 percent chance of snow showers, mainly after 1pm. Mostly cloudy, with a high near 30. South wind around 5 mph becoming calm in the morning. New snow accumulation of less than a half inch possible.

• Tuesday Night: A 50 percent chance of snow showers before 2am. Cloudy, with a low around 16. Northeast wind 3 to 7 mph. New snow accumulation of less than one inch possible.

• Wednesday: Mostly sunny, with a high near 22. Northeast wind around 7 mph.

• Wednesday Night: Mostly clear, with a low around 9. East wind 3 to 5 mph.

• Thursday: Partly sunny, with a high near 31. Southeast wind around 7 mph.

• Thursday Night: Mostly cloudy, with a low around 25. South wind around 7 mph.

• Friday: A chance of snow showers before 11am, then a chance of rain and snow showers between 11am and noon, then a chance of rain showers after noon. Mostly cloudy, with a high near 41. South wind around 6 mph. Chance of precipitation is 40%.

• Friday Night: Rain and snow likely before 11pm, then rain likely between 11pm and 4am, then rain and snow likely after 4am. Cloudy, with a low around 36. South wind around 6 mph becoming east after midnight. Chance of precipitation is 60%.

• Saturday: A chance of rain and snow showers. Mostly cloudy, with a high near 41. North wind 5 to 7 mph. Chance of precipitation is 50%.

• Saturday Night: A chance of rain and snow showers. Mostly cloudy, with a low around 30. North wind around 6 mph. Chance of precipitation is 30%.

• Sunday: Partly sunny, with a high near 39. Northeast wind around 6 mph becoming west in the afternoon.