Weather Blog Making Sense of Holes in the Clouds Scientists speculated about these holes for decades, but it’s now well understood that cavum clouds are caused by airplanes. Read More… About Author See author's posts Post navigation Previous Flood alerts issued across London as Met Office shares weather warningNext Erupting Volcano causes Yellow Alert… Related Stories Floods Inundate Southern Mozambique Weather Blog Floods Inundate Southern Mozambique January 27, 2026 Finding Freshwater in Great Salt Lake Weather Blog Finding Freshwater in Great Salt Lake January 26, 2026 Winter Grips the Michigan Mitten Weather Blog Winter Grips the Michigan Mitten January 23, 2026