Forecasters expect a cloudy and wet weekend with a slight chance of heavy rain or even thunderstorms as unstable atmospheric conditions and muggy Kona weather move over the state.

The National Weather Service issued a flood advisory for Maui this afternoon after radar indicated areas of nearly stationary heavy rain of 1 to 2 inches an hour.

The advisory expired just after 6 p.m.

Remnants of an old weather system that brought heavy rains to Maui Sunday and Monday moved back over the island from the Big Island this afternoon.

Moist and unstable atmospheric conditions, combined with cloud buildup from daytime heating and a lack of tradewinds is likely to bring afternoon showers to Oahu, Kauai and Maui Saturday. The rains could continue Saturday night and could become heavy.

Saturday may also start off cloudy and rainy, which could reduce daytime heating and the chance of afternoon showers.

Winds from the southeast are also bringing volcanic haze up from Hawaii island. The vog may be heaviest Saturday and Sunday until tradewinds return to blow it away Sunday night into Monday.

The forecast for Honolulu and south shores of Oahu calls for an 80 percent chance of rain Saturday. Showers are likely in the morning with the chance of isolated thunderstorms in the afternoon and evening. Vog is likely and winds will be from the south and southeast.

Sunday may start off sunny with isolated showers and turn partly sunny with scattered showers in the afternoon. There’s a 50 percent chance of rain and the vog is likely to linger as Kona winds continue.

Forecasters are calling for more rain to start the week on Monday morning as tradewinds start to return.

The winds could become breezy on Tuesday.