Wet weather to wrap up a dry December

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A series of wet weather systems are expected to wrap up an uncharacteristically dry December in Clark County, according to the National Weather Service.

Rain is forecast to begin tonight and continue for the next six days, said Rodger Nelson, a meteorologist at the weather service in Portland. Moderate temperatures will accompany the rainfall, Nelson said.

About an inch of rain is expected in the next seven days.

Anticipate temperatures in the lower 40s at night and daytime highs in the mid to high 40s, he said.

Despite the rainy conclusion to 2011, December could still attain the distinction of the driest on record in the Portland metro area, he said.

“We’ll have to wait and see,” he said.

A ridge of high pressure in the skies above the region has kept wet weather at bay during the month. That high pressure has now moved to the east, enabling rainy systems to move in, Nelson said.

Vancouver’s Pearson Airpark is 5.16 inches below the December average, he said.

“It’s pretty hard to catch up in six days,” he said.