storm drains and ditches may be clogged with debris from the fall foliage

Fri, 10/06/2023 - 6:15pm

Rockport Harbor Master’s Oct. 6 notice to mariners and alert to mooring holders summed it up: “Here we go again. Please make sure that your boat is secured and your dinghy is dry- We are expecting heavy rains through Saturday and swell and wind out of the southwest (very exposed in Rockport) on Sunday.”

The National Weather Service has issued a flood warning as a result of excessive rainfall. That forecast extends to Waldo County, interior and coastal; Knox, Lincoln, Kennebec and Somerset counties from Saturday afternoon through Sunday morning.

Runoff from the rain will overflow creeks and streams, and storm drains and ditches may be clogged with debris from the fall foliage.

“ I would expect the rainfall amounts locally to end up in the 2.0 - 2.5 inch range,” said Meteorologist Ken McKinley, Friday afternoon. McKinley is founder and owner of the Camden-based Locus Weather. “Most of it will fall Saturday night, so it will be a fairly heavy rain and will lead to some flooding of smaller streams and poor drainage areas. There will be areas of heavier rain, likely off to the east, perhaps up in the 3-4 inch range, and amounts to the west will not be quite as heavy. There is some uncertainty in the exact track of the heaviest rain, and if it is just a bit farther east or west, then the amounts here could be different.”

He added that the rain will be somewhat time limited, mostly tomorrow night, so the larger rivers will likely not see very big rises.

The NWS commented on hydrology, indicating that despite the last several days of dry weather, soil moisture leaves remain moist for the time of year, “given the winding down of the growing season.”

As the rains starts it will be able to infiltrate the ground, but heavier rains Saturday evening could overwhelm soils and resulting in rapid runoff.

The NWS described the approaching weather as a pair of surface low pressure systems in association with post- tropical storm Philippe that is heading for the Gulf of Maine on Saturday, with a cold front coming in from the west.

Winds will build out the southeast, increasing through the day Saturday and then backing and becoming westerly by early Sunday morning. Wind gusts expected from 25 to 30 mph, with a few near 40 mph, especially along the Midcoast.

Anticipate power outages with falling limbs and trees. Temperatures will be in the 60s, with lows in the 40s and 50s.