Last frost dates in Hawaii
2 NOAA weather stations in Hawaii have thirty years of frost records. The median station sees its last 32 °F night around Jan 26; across the state that ranges from Jan 26 to Apr 12, so pick the station nearest you rather than a state-wide figure.
Only 2 stations in Hawaii carry thirty years of complete frost records, so this list is short. The ZIP code lookup on the frost-dates page still finds the nearest station with data.
| Plan sowing from this date | ||||||
|---|---|---|---|---|---|---|
| KANALOHULUHULU 1075 | Jan 26 | May 16 | Dec 20 | Jan 24 | 365 | Plan sowing from this date → |
| MAUNA LOA 5 NNE | Apr 12 | May 18 | Mar 13 | Dec 1 | 235 | Plan sowing from this date → |
How to read the three dates
Average is the date by which, in half of the years between 1991 and 2020, the last 32 °F night had already happened. Safe is later: only one year in ten saw a frost after it, which is the date to transplant tomatoes and peppers, both killed by a single frost. Early is the risky end, with a frost after it in nine years out of ten.
Every figure is for the weather station, not for your garden. A valley bottom, a north slope or a spot near a lake can run a week or two either way. Cities are warmer than the countryside around them.
Where the numbers come from
The dates are NOAA's U.S. Climate Normals for 1991 to 2020, computed by the National Centers for Environmental Information for every station with thirty years of daily minimum temperatures. ZIP codes are matched to the nearest such station within 150 km using U.S. Census Bureau ZIP Code Tabulation Area centroids. Stations that never see a frost, such as much of south Florida, report no date and are left out.