The Broadmead Records contain this description of winter baptism, in 1666:

These 10 men and 4 women were all baptized together, one after another, the 6th day of March, in the Evening, at Baptist Mill, in the River, by Mr. Thomas, Minister.

Here behold the miraculous hand and worke of the Lord

Most of these persons now baptized, had neglected and omitted their duty all the Winter, for fear of the Cold; and then, about the beginning of February, it happened to be fine, warm weather; about which time they pitcht upon this day to passe under that Ordinance. And by reason our Pastor, by a fall that he received after he came forth of Prison, had a paine that did use to take him in the nature of a Sciatica, it was doubted for him to stand soe long in the Water might increase his said distemper; therefore the Brethren of the Church sent for Mr. Thomas, of Wales, to be the Administrator.

And the Lord in his wise Providence so ordered it, that when he came it was such Extreme Cold weather, the like had not been all that winter before, for Exceeding high and sharp piercing Wind, Frost, and Snow…One of the women to be baptized, in goeing to the place through the Meadows, her Handerchief received some wet, being about her Neck, was frozen … Her Maid that waited upon her told her if she went into the Water she would not come forth alive. Also another, Mr. Jenings, pained with the Toothache soe great that his face was very much swelled, bound up, and by reason whereof had not been out of his house near a weeke before, and that day very ill with it. Another of the men about a weeke before sprained his legge; not being able to goe, was carryed upon a horse to the place. Another man of them that was very weakly, thinn, and Consumptive. the relations of whom were very averse to the Ordinance.

Wherefore some did fear the Issue, seeing the terrible sharpnesse of the season. But the persons themselves that were to passe under the Ordinance, Acted faith in the Lord; and because the Administrator was come so farr on purpose, according to appointment, they would not deferr it any longer.

And the Lord, to declare his power, did, as it were, worke a Miracle, to give a Precedent to others that would fear the Coldnesse of any season to doe his will; but the Lord preserved them all; and not so much as one ill, but rather better by it; and are all alive to this day, being about 10 years since, to speake of the Lord’s then goodness …

Therefore from all, Praise, Praise, Praise, and Glory be to the Lord.