A plume of moisture is lingering over Kauai today, according to National Weather Service forecasters, while isolated to scattered showers are expected from Oahu to the Big Island.

The moisture plume is expected to drift back over Oahu on Thursday, increasing shower activity. Light winds and showers are then expected from Thursday into the weekend, forecasters said.

Today’s highs range from 87 to 93 degrees Fahrenheit, with easterly winds of 10 to 20 miles per hour. Tonight’s low range from 74 degrees to 79.

The heat index, a measure of what it feels like when temperature and relative humidity are combined, is expected to reach as high as 99 degrees in Kahului, 95 in Honolulu, 94 in Kapolei and Lihue and 92 in Hilo this afternoon.

On Monday, a high of 94 degrees in Kahului matched the previous record set in 1993, continuing a daily trend of record highs and ties for the month of September.

Since April, more than 190 record highs and ties have been recorded throughout the isles, according to Jerome Saucier, NWS observing program leader, and the trend could continue into next month.

Tropical Storm Kiko weakened overnight and is is expected to move into the Central Pacific later this afternoon, according to the National Hurricane Center. Kiko is expected to become a remnant low on Wednesday.