Note: Single-source report; awaiting corroboration.
On the last day of astronomical winter, March 19, 2026, a NASA satellite captured an image displaying diverse cloud formations over the Gulf of Alaska, highlighting the region’s atmospheric instability as winter transitioned to spring.
According to a NOAA weather briefing, low pressure over the Gulf and high pressure over eastern Russia and northern Alaska drove Arctic air southeast over the Alaska Peninsula. This produced cloud streets—parallel bands formed as cold, dry air picked up moisture moving over warmer ocean water. As the air mass moved farther over the ocean, these cloud streets evolved into open-cell clouds with wispy edges around clear areas.
Near the coast, skies were mainly clear, though some stratus or sea fog was present near shore. Another feature observed was the von Kármán vortex streets near Unimak Island, created by wind diverting around the island’s terrain and forming staggered, counter-rotating swirling cloud patterns.
Further southwest of Anchorage, meteorologist Matthew Cappucci identified a polar low—a small cyclonic system in cold polar air over warmer water—with tropical storm-force winds that generated snow and thunderstorms near its center.
After March 19, Alaska saw sustained cold and several storms, while by late April, conditions warmed. However, unsettled and rainy weather was expected ahead in Southcentral and Southeast Alaska due to an approaching atmospheric river.
The image data came from NASA's MODIS instrument and was produced by Michala Garrison for NASA Earth Observatory.