Shepherd’s Warning?

Many know the old saying:
‘red sky at night, shepherd’s delight;
red sky in morning, shepherd’s warning’

But what is the warning?

By my observations red skies in the morning often herald a glorious day. Three days ago, the morning of 8 September, was no exception. The sky at 6:30 a.m. was magnificent and I was compelled to step outside, still in my PJs, camera in hand. It was worth it.

My question is …
what is the warning?

• a corker of a day
• too warm for sheep
• better get the drinks in
• plant more shade trees for the sheep

Or was ‘warning’ the only word that sort-of rhymed with ‘morning’?

The science

According to the Met Office website the old weather saying originated from the book of Matthew in the Christian Bible. It helped to prepare shepherds in the care of their flocks, and is reflected in current ‘scientific understanding’. With provisos.
The Met Office says that in the UK, where weather systems are predominantly from the West, the saying is often proved true.”
A red sky appears when dust and small particles are trapped in the atmosphere by high pressure. This scatters blue light leaving only red light to give the sky its notable appearance.” With high pressure coming from the West the following day should be dry and pleasant.
When the high-pressure weather system has passed over and is in the East “the good weather has passed” and a low-pressure weather system with wet and windy weather is more likely.

My husband wrote in his journal for the 8th:
“Sunny start. 25.4⁰ C this afternoon. Is this to be the last hot day of 2021?”

Do you have an explanation? Does having red sky all around signify that we were in a transition phase as the high-pressure system moved East?
Any thoughts? I’d love to know.

Maz X