Morning Glory Over Southeastern Brazil

October 14, 2014

1-CANON 007-003

Photographer: Meire Ruiz
Summary Authors: Meire Ruiz; Jim Foster
October 2014 Viewer's Choice
The photo above shows a weather phenomenon known as a morning glory, as viewed near Itanhaem, Brazil on November 11, 2013. This is a type of roll cloud -- a detached storm cloud. In northern Australia, Morning Glories occur in the Gulf of Carpentaria during the month of October with some regularity. Though their formation isn't completely understood, mesoscale circulation, such as stiff sea/land breezes appear to be crucial to their development. In different areas of the world, they've been observed to form at times of day other than morning. Strong winds can accompany the passage of these tubular clouds so beachgoers should heed their approach. Compare this cloud to the Earth Science Picture of the Day for October 2, 2014 showing a rolling fog.
Photo Details: Camera: Canon PowerShot SX40 HS; Focal Length: 4.3mm; Aperture: f/4.0; Exposure Time: 0.0031 s (1/320); ISO equiv: 100.