The weather is important in gauging the likelihood of light levels of radiation leaking from the plant reaching heavily populated areas, especially Tokyo to the south, or entering the food chain.
So far the wind has blown mainly out into the Pacific.
The damaged Fukushima Daiichi plant, run by Tokyo Electric Power Co. (TEPCO), is about 240 km (150 miles) north of Tokyo.
The easterlies are expected to change to light northwesterlies, again heading into the Pacific, later in the day, according to the forecast.
The northwesterlies are expected to change to light southeasterlies towards Tuesday, according to the forecast.
Some 5-10 mm of rain is forecast over the next 24 hours.
Three hundred engineers have been battling inside the danger zone to try to cool down the reactors which were ravaged by the quake and tsunami on March 11.
Read the rest of the story: Light winds, rain forecast near Japan nuclear plant.