1816 in New England became famous for its lost crops due to repeated cold events during the growing season. I forget when I first learned about the year, but I learned about a granite monument to it in Ashland NH in a 1979 article in Scientific American by Henry Stommel that included a photograph of it.
I finally hunted it down when I decided it would be a good Geocache, and found it on chilly day in mid-May. The next day while I was cooking breakfast, rain changed to snow. 1816 weather the day after I find and touch the monument!
I wrote a web page about the year's impact on New Hampshire to extend the description in the Geocache and also to make it available to people outside of Geocaching. See 1816: The Year without a Summer - A New Hampshire Perspective
For the 200th anniversary in 2016, I decided to write a much longer essay looking at the weather that led to events of the year. There is a lot of data available, not on the web, but in various historical libraries. For New Hampshire, my primary reference is a farmer's journal maintained by our governor at the time, William Plumer. It may be the only such journal in the state, though I think Dartmouth College may have temperature data too.
See Summer of 1816 in New Hampshire: A Tale of Two Freezes or see a variant with many comments at the blog Watts Up With That.
The following link is for a .pdf file scan of William Plumer's weather journal. The link is somewhat hidden from search engines because a Chinese search engine seems to think it's a good idea to download another large .pdf file every day.
Contact Ric Werme or return to his home page.
Written 2016 Jun 7, last updated 2018 Mar 9.