This is what I know about Hawaii Field Day 2018. It is hard to get information for some reason but thanks to those who responded and or have information on your websites.

Maui Island
Maui ARC will be doing a 3A Field Day on all HF bands and maybe VHF at our usual site near Ho’okepa beach.

Location details here: scroll down to Field Day.
The public is welcome.
Friday June 22 through Sunday June 24.

Trip, WH6FAM Club President
Alan, AD6E Club Secretary

Oahu Island

Friday, June 22 08:00 am to Sunday June 24 08:00 am
LOCATION: Kualoa Regional Park
SCHEDULE: open to the public from 8:00 am to 5 pm Saturday.
On the left side, select Field Day under Event Info

Big Island
Field Day
Big Island Amateur Radio Club – BIARC
The club will be at Reed’s Bay Hotel in Hilo. Come to the June 9th meeting at 2PM at Puna Covenant Church for details.

Kona Amateur Radio Society – KARS

South Point Amateur Radio Club
Down at Whittington’s beach with the SPARC

Kauai Island