The weatherwise mare of Asmund in the Icelandic saga of
Grettir the Strong (ca. eleventh century). Asmund believed in
her weather prophecies, and when he charged his second son,
Grettir, with looking after the horses, he told Grettir to be guided
by Keingala, who would always return to the stable before
a storm. Because Keingala persisted in remaining on the cold
hillside, grazing on the scanty grass until the lad was nearly frozen
with cold, Grettir determined to make her return home regardless
of the weather.
One morning, before turning out the horses, Grettir tore off
a long strip of her skin from withers to flank. This made the
mare soon seek her stable. When Keingala did the same thing
the next day, no storm impending, Asmund himself let out the
horses and discovered his sons cruel trick.