Jaime Brown (Member 61,618) was travelling to Corpus Christi, Texas, US to spend the night on the USS Lexington aircraft carrier with her family and a Scout group. On the way, she told us, she saw above Pleasanton, Texas a ‘sky blanket that suddenly stopped, with clearer skies opening up beyond.’

Clouds generally form wherever warm, moist air is forced upwards and cools enough as it rises for its moisture to condense into droplets or ice crystals. Clear skies result from the opposite: cool, dry air that is sinking. Such a distinct boundary between Stratocumulus clouds and deep blue sky likely marks a retreating weather front – the back of a cold front, where sinking dry air forces the cloud layer to evaporate. ‘It was such an interesting sight,’ said Jaime, ‘to see the edge of what usually seems to go on forever.’