Rivers Rise, Flooding Closes ​Griggstown Causeway In Somerset County

MONTGOMERY, NJ — Rain continues to fall in Somerset County causing rivers to rise and flooding closures.

Somerset County Public Safety announced around 11:30 a.m. that the Griggstown Causeway is closed until further notice due to flooding.

As of 11:50 a.m., the Millstone River at Blackwells Mills is at 5.67 feet high just below the Action stage of 7 feet. The National Weather Service is projecting the river will continue to rise to 9 feet at the Minor Flood level by 8 a.m. on Saturday.

As of noon on Wednesday, other rivers in the County are also rising but no alerts or warnings have been issued for them yet.

The Raritan River in Bound Brook is at 20.59 feet under the Action Stage of 26 feet. Projections show it will rise throughout the week.

The Raritan River in Manville is at 5.84 feet, well below the Action Stage at 12 feet. Yet projections show it may rise throughout the week.

The North Branch River near Route 202 and Millstone Road is at 3.49 feet, well under the Action stage of 8 feet. But projections show it may rise close to Action Stage.

More rain is forecasted to fall on Wednesday and Thursday.

"Flash flooding concerns will continue over the next 3 days," said US National Weather Service Philadelphia/Mount Holly on Wednesday morning.

Here is a look at the upcoming forecast:

Wednesday Night: Scattered showers and thunderstorms. Mostly cloudy, with a low around 64. East wind around 5 mph. Chance of precipitation is 40 percent. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Thursday: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 7 a.m. Mostly cloudy, with a high near 75. East wind 5 to 10 mph. Chance of precipitation is 70 percent. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Thursday Night: Showers and possibly a thunderstorm. Low around 70. East wind around 5 mph. Chance of precipitation is 90 percent. New rainfall amounts between a quarter and half of an inch possible.

Friday: Showers and possibly a thunderstorm. High near 82. South wind 5 to 10 mph, with gusts as high as 25 mph. Chance of precipitation is 90 percent. New rainfall amounts between three quarters and one inch possible.

Friday Night: Showers and possibly a thunderstorm. Low around 70. Chance of precipitation is 90 percent. New rainfall amounts between three-quarters and one inch possible.

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