The "Winter Storm Watch" issued early Thursday for southwestern Connecticut has been changed to a "Blizzard Warning" by the National Weather Service.

A pounding winter nor'easter -- with wind-driven snow and possible coastal flooding -- is now forecast to strike the region most intensely from 6 a.m. Friday through 1 p.m. Saturday, according to the NWS alert Thursday night.

Light snow may start falling overnight as the temperature dips to a low in the low-20s. There will be an east wind 8 to 14 mph; chance of precipitation is 50 percent Thursday night into early Friday. Total nighttime snow accumulation of less than one-half inch possible.

On Friday, snowfall gathers intensity and could be heavy at times. The high temperature will reach the low-30s, with a northeast wind 14 to 21 mph, with gusts as high as 37 mph. Chance of precipitation is 100 percent. New snow accumulation of 3 to 7 inches possible during the day.

By Friday night, snow will continue falling heavily as the temperature dips to about 20 degrees, the NWS says. It will be windy, with a north wind 23 to 26 mph, gusting as high as 44 mph. Chance of precipitation is 100 percent, with new snow accumulation of 10 to 14 inches possible.

On Saturday, snow is expected to continue falling before noon. Cloudy skies will gradually clear by afternoon as snow eases. The high temperature will be in the mid-20s, with a north wind 22 to 26 mph, gusting as high as 40 mph. Chance of precipitation is 60 percent, and the NWS forecasts new snow accumulation of 1 to 2 inches possible.

Sunday is expected to sunny with a daytime high temperature in the mid-30s.

The outlook for Monday, according to the weather service, is possible rain and snow, with temperatures in the mid-40s.