Usually, sun pillars (right) develop under thin, high clouds that drop plate-shaped ice crystals (snow) which reflect the low-angle sunlight back to the attentive eyeball. Here, some of those crystals were being launched by convective clouds—specifically altocumulus formations that earlier offered a beautifully geometric pattern in the sky. In wintertime, ice-process altocumuli are common; the wild card is whether they produce sufficiently reflective crystal shapes for pillars.
5 W Little Axe OK (11 Feb 13) Looking SW
35.2295, -97.3019Sun Pillar
Usually, sun pillars (right) develop under thin, high clouds that drop plate-shaped ice crystals (snow) which reflect the low-angle sunlight back to the attentive eyeball. Here, some of those crystals were being launched by convective clouds—specifically altocumulus formations that earlier offered a beautifully geometric pattern in the sky. In wintertime, ice-process altocumuli are common; the wild card is whether they produce sufficiently reflective crystal shapes for pillars.
5 W Little Axe OK (11 Feb 13) Looking SW
35.2295, -97.3019