A mid-October nor’easter will continue to intensify as it tracks up the East Coast, bringing with it the potential for heavy rain and powerful winds that could knock out power this weekend. The storm will also bring significant coastal impacts to parts of the East Coast into early next week.

As of Saturday, the storm is forecast to impact major Northeast locations along the East Coast with at least 1 to 3 inches of rain and 20 to 40 mph wind gusts possible from the Carolinas up to New England.

Coastal areas are likely to see upward of 4 inches of rain with 50 to 60 mph wind gusts. Major and damaging coastal flooding, along with significant beach erosion and high surf are also likely for these areas.

Over 21 million people along the East Coast remain under a coastal flood watch or warning where moderate to major coastal flooding is forecast.

Here’s what you need to know about the timing of the storm and potential impacts:

In the Southeast

Heavy rainfall and gusty winds from the developing coastal low will continue to impact the Carolinas on Saturday evening, where conditions will continue to worsen. Rain and showers will become more scattered on Sunday, though times of moderate to heavy rain are still likely.

A nor’easter is developing off the Florida coast, with coastal flooding and high surf visible in areas along the East Coast.

Much of the North and South Carolina Coast has already seen between a half inch to an inch of rain over the last 24 hours. an additional 1 to 2 inches of rain into Sunday could increase the potential for flash flooding, putting the region under a marginal to slight risk for excessive rainfall through Sunday morning.

Additionally, embedded thunderstorms pushing on shore could bring more heavy downpours, gusty winds and perhaps even a spin-up tornado or two across eastern North Carolina and the Outer Bands.

Rain aside, winds will remain strong, especially along and near the immediate coast. Just offshore Wrightsville Beach, North Carolina, a wind gust of 60 mph was reported Saturday evening. A 40-mph gust was reported in Beaufort Smith Field in southeast North Carolina.

However, most gusts on land near the coasts of North and South Carolina have only ranged between 25 and 35 mph for the most part.

Already, there have been serval reports of coastal flooding along portions of the Florida and South Carolina coastline. Coastal flooding will especially remain a concern for much of the Carolinas through at least Sunday, where coastal flood alerts remain in effect.

Along with coastal flooding, high surf with large breaking waves, dangerous rip currents and beach erosion will also impact the Carolina coast through Sunday where numerous alerts remain in effect.

In the Northeast

Despite clouds and some passing showers, much of the impacts from this storm system won’t affect the Northeast until later Saturday into Sunday. As the system tracks towards the north and east, its center of circulation will broaden, spreading steadier and heavier rain into the region from south to north.

Widespread rain will keep much of the region quite soggy Sunday into Monday morning, with periods of heavy rain expected.

Rain and showers will become more intermittent and scattered in nature on Monday, but times of heavy rain at times will still be possible. Conditions will then begin to dry out on Tuesday as this system pulls away from the coast — although will send more rain and showers to the New England coast.

Total rainfall totals from this will generally range between 1 to 3 inches across much region, with areas closer to the coast seeing locally higher amounts.

Winds will pick up significantly by Sunday as the storm tracks north and east, too. Wind alerts stretching from up the East Coast from Virginia to Cape Cod will remain in effect through Sunday and into Monday for gusts reaching between 40 to 50 mph.

However, high wind warnings have been issued along the immediate coastline for potential gusts reaching up to or over 60 mph.

Strong winds alone could be enough to bring down trees and power lines, which could lead to widespread power outages. But saturated grounds will only make it that much easier to topple over.

Like in the Southeast, the storm system will bring strong and persistent onshore flow to the Northeast coast through Tuesday of next week. As a result, coastal flooding remains a huge concern, particularly during hide tide.

Coastal flood alerts remain in effect up the entire Mid-Atlantic and southern New England coastline through Monday, where moderate to major coastal flooding is possible during times of high tide across portions of the Delmarva, Jersey Shore, Long Island and New York City beaches.