COASTAL FLOOD WARNING, HIGH WIND ALERTS FOR LONG ISLAND

Enjoy another dry albeit chilly day today, as a stormy Saturday awaits.

The strengthening nor’easter will bring rain, wind, coastal flooding, and beach erosion to Long Island, beginning around midnight. It won’t be the strongest coastal storm we’ve seen, but it will still have impacts on our area.

Once the first drops fall, the rain will turn steady and heavy. It will be worst though the morning until about lunchtime. Localized flash flooding is possible, especially with the leaves finally starting to fall and clogging storm drains. Wind will also be at its worst in the morning: sustained out of the NE at 20-30 mph, with gusts over 40 Рpossibly over 50 in eastern Suffolk.  A wind advisory is in effect for Nassau and western Suffolk from 1am through noon, with a high wind warning for the east end. As the ground becomes saturated and the soil loosens, older/larger trees and power lines may topple. This could lead to spotty outages.

Latest HRRR showing Long Island receiving the heaviest rain in the Tri-state, peaking 6-9am.

Friday morning 12z NAM showing strongest winds for the eastern half of Long Island, peaking 6-9am.

And it wouldn’t be a coastal storm without the coastal flood threat. Warnings have been issued for the south and north shore, as well as all bays. The warning is for tomorrow morning’s high tide cycle, where water levels may run as high as 3′ above normal in spots. Tidal abnormalities of 2-3′ falls under the ‘moderate’ coastal flooding designation. The warnings will likely be replaced with coastal flood advisories for Saturday afternoon and Sunday morning, where tides may still be 1-2′ above normal – ‘minor’ coastal flooding. Check your local tides here.

A high surf advisory is also in effect from 6am to 6pm Saturday. Breaking waves of 7 to 11 ft along the ocean shoreline will result in widespread beach flooding and erosion, with minor damage possible to dune structures during times of high tide Saturday morning and Saturday Night, possibly even into Sunday morning. On the waters, gale and storm warnings are in effect during this time frame. Boaters beware.

Tie this altogether with temperatures in the low 50s? Yuck. It will feel more like the 40s. Indoor plans are highly suggested. Weather slowly improves Saturday afternoon and evening. There will be some lingering showers and areas of drizzle into Saturday night. Sunday starts off cloudy, with some breaks of sun possible in the afternoon. Temperatures will also be a few degrees milder.

After the Sunday break, the rain returns on Monday, followed by clearing and blustery conditions on Tuesday. That sets the stage for Halloween. High pressure will be settling in but looks to be further south than it did the other day. This is good because southwest winds will usher in milder air. Temperatures may reach the 60s during the day, which means fairly comfortable trick-or-treat weather. The GFS shows a weak but fizzling cold front off to the west, and the CMC has a weak warm front passing well to the north. Either way it looks like dry & above average!

Be safe, and have a great weekend!

Meteorologist Geoff Bansen