The last three days of March have a reputation for being incredibly stormy. Scottish folklore suggests these three days were borrowed from April so that March might extend his power.
According to the Irish folklore, the old brindled cow boasted that even March’s fierceness could not kill her. March then borrowed three days from April and, doubling the days’ fury, killed and skinned the poor old cow.
In parts of Northern Ireland, the story was more elaborate with nine borrowed days instead of three. The old legend states that the blackbird, the stone-chatter and the old grey cow bid defiance to March after his days were done and to punish their insolence, he begged of April nine of his days, three for each of them for which he repaid nine of his own:
Trí lá lomartha an loinn,
Three days for fleecing the black-bird,
Trí lá sgiuthanta an chlaibhreáin,
Three days of punishment for the stone chatter,
Agus trí lá na bó riabhaighte.
And three days for the grey cow.
Superstition regarding the “borrowed days” continued well into the 19th Century, and most viewed these as dangerous days, fraught with bad weather. After King James I died at the end of March during a storm that battered the Scottish coast, one writer mourned the result would be "long after remembered as the storm of the Borrowed Days."
Even the Spanish have folklore about these days. The tale says a shepherd promised to give March a lamb if he would reduce the strength of his winds to save his flocks against harm. But once March had done so, the shepherd refused to hand over the lamb. In revenge, March borrowed three days from April, and used them to produce even fiercer winds in order to pay back the shepherd for his deceit.