Unstable atmospheric conditions and rain clouds being blown in by breezy tradewinds are bringing showers to windward and mauka areas and the slight chance of thunderstorms. Leeward areas should see sunny skies with an occasional shower blown over the mountains by the tradewinds. The National Weather Service says a weather system south of Kauai is creating unstable atmospheric conditions and a slight chance of thunderstorms. Some thunderstorms passed south and north of Oahu overnight, but the thunder and lightning did not come ashore. The moisture in the air is also creating some muggy conditions. Sunday night and Monday should see a repeat of Saturday night and Sunday morning — with overnight showers in windward and mauka areas and some rain over leeward sections. The forecast for southern shores of Oahu, including Honolulu, calls for a 50 percent chance of rain Sunday night and Monday. Forecasters expect tradewinds to drop off starting Monday night into Wednesday. A weather system northwest of Kauai could also move over Kauai and Oahu Tuesday night, bringing an increased chance of showers. Tradewinds should pick up again on Wednesday.