Radar images viewed at about 5:20 a.m. today showed persistent heavy showers near Ahuimanu on O'ahu's windward coastline, or over the Koolau Mountain Range about 10 miles north of downtown Honolulu.

The heavy showers were nearly stationary.

The Weather Service is warning hikers and campers to be alert, watch for rapidly changing conditions and to stay away from streams and low lying areas.

A wave of low pressure is expected to pass just north of the islands later tonight and early Thursday morning.

The low will turn the winds from light trades to moist southerlies later today and continuing tomorrow, forecasters said.

The change in winds is expected to bring cloudy, humid weather and locally heavy showers, especially for Kaua'i and O'ahu. Things should clear up a bit as we get closer to the weekend, although the humidity is likely to hang around until early next week when the trade winds make a return.

Here's how the next few days are shaping up:

Today, mostly cloudy with scattered showers. Highs 77 to 83. East winds 10 to 15 mph. Chance of rain 50 percent.

Tonight, mostly cloudy with showers likely and slight chance of

thunderstorms. Lows 67 to 73. Northeast winds around 10 mph. Chance of rain 60 percent.

Thursday, partly cloudy with scattered showers. Highs 79 to 84. South winds 10 to 15 mph. Chance of rain 50 percent.

Thursday night, mostly cloudy with showers likely. Lows 69 to 74. Southwest winds 10 to 15 mph. Chance of rain 70 percent.

Friday, mostly cloudy with showers likely. Highs 78 to 85. South winds 10 to 15 mph. Chance of rain 60 percent.