Northwest Georgia is in for a significant weather change this weekend, with unseasonably warm conditions giving way to increasing rain chances, the potential for locally heavy rainfall and noticeably cooler temperatures by Sunday and early next week.

Friday will remain warm and humid, with mostly sunny skies and a high near 89 degrees. A slight chance of showers and thunderstorms develops during the afternoon and evening, with rain chances around 20 percent. Winds will remain light, becoming southerly at around 5 mph during the afternoon.

Friday night will stay mild and humid, with partly cloudy skies and a low around 68 degrees. A few isolated showers or thunderstorms will remain possible overnight.

Rain chances increase more substantially Saturday as deeper moisture continues moving into the region. Showers and thunderstorms are expected to become more widespread during the day, with a 60 percent chance of rain and a high near 87 degrees. Saturday night looks even wetter, with a 70 percent chance of showers and thunderstorms and a low around 68.

Some of Saturday’s storms could produce locally heavy rainfall, especially where repeated showers move over the same areas.

Sunday is expected to be the wettest and coolest day of the weekend. Showers are likely, with thunderstorms also possible, and the chance of rain increases to 80 percent. Temperatures will be much cooler, with a high near 75 degrees.

The National Weather Service says a very moist air mass will remain in place across Georgia while a frontal boundary stalls near the northern part of the state. At the same time, tropical moisture will continue feeding northward from the Gulf, creating favorable conditions for periods of heavy rain.

Forecasters say North Georgia could receive between 1.5 and 3 inches of rainfall through the period. The exact placement of the heaviest rainfall remains uncertain, but localized flooding could become a concern, particularly in low-lying areas, poor drainage locations and places that receive repeated rounds of heavy rain.

The Weather Service is also monitoring the potential for excessive rainfall across the region through the weekend.

While thunderstorms are possible Friday through Sunday, severe weather is not currently expected to be the main concern. Heavy rainfall and localized flooding appear to be the greater threats.

Conditions begin improving early next week as the front finally pushes south and a much drier and cooler air mass moves into North Georgia.

Monday will be partly sunny with a high near 81 degrees. Tuesday turns mostly sunny with a high near 78, followed by a low near 50 Tuesday night. Wednesday looks sunny and pleasant with a high near 76, with another cool night around 50 degrees.

By Thursday, sunshine continues with a high near 81.

The extended forecast represents a noticeable transition from summerlike warmth to more typical early October weather, with cooler afternoons, crisp nighttime temperatures and drier conditions expected by the middle of next week.