The tradewinds will be on the uptick today and tonight, according to forecasters, and last through the weekend.

The National Weather Service said showers from the flow will focus on the windward side, mostly nights and early mornings. Some will likely fall over the leeward slopes of Hawaii island in the afternoons.

Today’s forecast is mostly sunny with scattered showers and highs from 87 to 92 degrees Fahrenheit. Tonight is expected to be partly cloudy with lows from 71 to 76 degrees. East winds are expected to clock in at 15 to 20 mph day and night.

Due to high humidity, the heat index — what it feels like when humidity and temperature are combined — will reach 91 degrees by noon in Honolulu as well as Kapolei today.

High pressure to the north of the islands is driving the increase in trades and will keep them in the moderate to locally breezy range through the upcoming weekend.

Surf, meanwhile, will remain small on all shores through Wednesday.

Surf along south shores is expected to remain 1 to 3 feet through Wednesday, with mainly background southerly swell energy producing small surf.

A slightly larger south swell is expected to arrive late Wednesday and may bump up surf heights Thursday and Friday.

Surf along east shores is expected at 2 to 4 feet through Wednesday and may rise slowly as the trades increase locally and upstream of the islands.

Surf along west shores will be 1 to 3 feet, while surf along north shores will be 2 feet or less through Wednesday.

Forecasters expect a mid-to-upper level low to move toward the islands later in the week, possibly increasing winds at Haleakala and Hawaii island during the end of the weekend and early next week.

Tropical Storm Cristina, meanwhile, has formed in the eastern Pacific, and was centered late this morning about 415 miles south-southwest of Manzanillo, Mexico, with maximum sustained winds of 45 mph. She was traveling northwest at 13 mph.

The National Hurricane Center forecasts Cristina will become a hurricane on Wednesday — the first of the 2020 eastern North Pacific hurricane season.

NHC spokesman Dennis Feltgen said it is far too early, however, to determine if she will make it into the Central Pacific basin and at what strength, at this point.

A small craft advisory, meanwhile, has been issued for Maalaea Bay, Pailolo and Alenuihaha channels, and leeward and southeast Hawaii island waters, effective through 6 p.m. Wednesday.