The Art of Staring at Blue Skies
This video is a time lapse of a couple of hours of looking out over the western horizon.
Keep an eye on the passage of the high thin clouds as they scud across the mostly blue sky.
Notice how the wind is coming from the bottom right at the start of the picture (northwest) but from dead ahead by the end (west). It has ‘backed’, turned anticlockwise, from northwest to west.
Together with the cloud changes – note the puffs of wispy cirrus appearing near the end too – this is a strong sign of a front and bad weather are approaching.
Heavy rain and gales started 18 hours after I filmed this.
This video illustrates one of the concepts in Chapter 3 of the book, The Secret World of Weather: