Boston weather forecast maps show potential nor'easter coming to Massachusetts this weekend

There's a potential nor'easter in the Boston area weather forecast this weekend, just as fall officially begins.

Nor'easters are not always a winter or snowy phenomenon. 

What is a nor'easter?

Nor'easter is actually a blanket term for a coastal storm that impacts New England with its primary wind direction being from the northeast. They are more common in the late fall, winter and springtime.

I have to stress that it is still early in the forecast cycle for this storm. A lot can and will change in the next few days.

We are confident that a powerful ocean storm will form later this week and likely will impact Massachusetts to some degree this upcoming weekend.

How long will it last?

What we still need to determine is how close the storm comes to our shoreline and how long it lingers.

Perhaps the biggest factor with this storm is how long it is forecast to stick around. The dip in the jetstream is going to be so severe that this storm will be cut off from the typical west to east flow of the atmosphere. When this occurs, the impacts from the storm can last for several days.

While the storm system sits and spins to the south, a large area of high pressure will remain nearly stationary over the upper Midwest. This is a classic setup for a prolonged nor'easter in southern New England. 

In these situations, the highest impacts from rain and wind are almost always located close to the coastline, from the North Shore of Massachusetts down through the Cape and Islands.

One particular weather model shows very little movement between Saturday (when the brunt of the rain and wind starts to arrive) and early next week.

If this forecast and storm track holds, we will be talking about nearly seven straight days of gusty northeasterly winds, peaking over the weekend.

This is likely to cause major beach erosion, particularly along the northeast and east facing beaches in southern New England. Northeasterly gusts will remain 25-to-35 mph over the next few days, ramping up to potentially as high as 40-to-55 mph this weekend right at the coast.

By this weekend, swells will reach over 10 feet just offshore as tides continue to grow each day. The highest tides of the month occur early next week, and we will be building towards that crescendo each day. Given this forecast, there will almost certainly be some areas of minor coastal flooding along northeast facing shorelines over the course of several days.

How much rain?

Rainfall amounts are tricky to forecast, as they are highly dependent upon the ultimate track and duration of the storm. There is the potential for several inches of rain across eastern Massachusetts between Saturday and Tuesday.

If you have outdoor plans this weekend, don't cancel them just yet, especially if you live well north and west of Boston. However, I would absolutely start to formulate a "backup plan" and stay tuned to weather updates this week.

If you are a coastal resident, you likely know what precautions you need to take with a potential nor'easter in the  forecast. You should begin to plan for what could be several consecutive high tides with some degree of flooding as well as wind gusts that could reach or exceed 50 mph over the weekend.

We are not too concerned with inland flooding given the recent drought. However, if your home or basement is prone to flooding, it may be a good time to check the sump pump.

As always, we urge that you stay tuned to updated forecasts on WBZ-TV and CBS News Boston.