https://www.nytimes.com/athletic/315647/2018/04/15/mccaffrey-it-was-the-most-miserable-day-at-fenway-but-even-the-cold-can-stop-red-hot-red-sox/
There’s been other 34° starts, but the key take there is that gametime temps weren’t consistently taken before 2000.
I get it from distilled water from my dehumidifier. Not sure about my well, but there may be salts already dissolved in that so there is less leeching from the concrete? It’s definitely efflorescence though.
It has to break sometime, but we’ve been kicking the can a bit on it. There’s been too much cold lingering in S Can. But yeah, around that time it looks like the cold starts to get choked off up to James Bay. Hopefully we flip a switch mid month.