Last weekend’s beautiful weather in St. Lawrence County changed signifcantly today as heavy afternoon rains poured down with more thunderstorms expected through Tuesday.

The National Weather Service is predicting an 80 percent changes of precipitation tonight, a 90 percent chance during the day on Tuesday and a 60 percent chance Tuesday night.

For up-to-date predictions for your community, visit the NorthCountrynow.com Weather Page.

The complete seven-day forecast follows:

• Tonight: A chance of showers and thunderstorms, then occasional showers and possibly a thunderstorm after 10pm. Low around 66. South wind 3 to 7 mph. Chance of precipitation is 80%. New rainfall amounts between a half and three quarters of an inch possible.

• Tuesday: Showers and possibly a thunderstorm. High near 74. South wind 5 to 7 mph becoming west in the afternoon. Winds could gust as high as 30 mph. Chance of precipitation is 90%. New rainfall amounts between a half and three quarters of an inch possible.

• Tuesday Night: Showers likely, mainly before 8pm. Mostly cloudy, with a low around 61. West wind around 5 mph. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.

• Wednesday: A chance of showers before noon, then a chance of showers after 1pm. Mostly cloudy, with a high near 70. West wind 6 to 8 mph. Chance of precipitation is 30%. New precipitation amounts of less than a tenth of an inch possible.

• Wednesday Night: A 30 percent chance of showers before 7pm. Mostly cloudy, with a low around 57. West wind 3 to 6 mph. New precipitation amounts of less than a tenth of an inch possible.

• Thursday: Mostly sunny, with a high near 75. West wind 5 to 9 mph.

• Thursday Night: A 30 percent chance of showers after 2am. Mostly cloudy, with a low around 61. South wind 7 to 9 mph.

• Friday: A 50 percent chance of showers. Mostly cloudy, with a high near 78. Southwest wind around 11 mph.

• Friday Night: A 40 percent chance of showers. Mostly cloudy, with a low around 61. Southwest wind 3 to 7 mph.

• Saturday:A 30 percent chance of showers. Mostly sunny, with a high near 78. Northwest wind 3 to 6 mph.

• Saturday Night: Partly cloudy, with a low around 59. Calm wind.

• Sunday: Mostly sunny, with a high near 79. Calm wind becoming west around 6 mph in the afternoon.

• Sunday Night: Mostly clear, with a low around 60. Calm wind becoming south around 5 mph after midnight.

• Monday: Mostly sunny, with a high near 80. Southwest wind 6 to 9 mph.