The overnight temperature from Sunday to Monday in Banyalbufar didn't drop below 20C. This is the temperature which is defined by Aemet as "tropical" and is normally only experienced between May and October and especially in July and August.
Maria José Guerrero of Aemet says that there was a very localised effect caused by a layer of warm air close to the mountains at a low to medium height and with a southwest wind. Banyalbufar was the most affected by this.
Elsewhere in the Tramuntana there were higher temperatures than normal. In Lluc, where the typical overnight temperature for early March is only just over three degrees, it reached 15.4C. The contrast with other parts of the island was striking. In Campos, for instance, the Sunday night temperature was down to 3.8C.
Guerrero stresses that tropical overnight temperatures in March are not normal.