Hurricane Ian bathed the Mid-Atlantic in a spectacular sunset Thursday

WEATHER NEWS: Hurricane Ian bathed the Mid-Atlantic in a spectacular sunset Thursday

As Hurricane Ian lumbered toward the Southeast coastline for its second U.S. landfall, it delivered high clouds up and down the Mid-Atlantic, which bathed the region in a stunningly colorful sunset Thursday evening.

2016: As Hermine skimmed D.C., it put on a first-class show in the sky

The common saying “red sky at night, sailor’s delight,” usually indicates storminess has passed, because storms tend to move from west to east in the northern hemisphere, opposite the direction of the setting sun which casts light on the departing clouds. But tropical storms often move in the opposite direction in the eastern United States, from the sea to land — not so much a sailor’s delight.

Brilliant sunsets are common on the edges of big storm systems, which allowed us to give a heads up that it was coming several hours before it happened. While beautiful skies can complement the approach of any low-pressure area, tropical systems tend to fan high clouds out farther, and away from lower clouds which tend to dull sunsets.

The cirrus cloud deck — mixed with some stratocumulus — that was illuminated Thursday evening was about 25,000 feet high based on observations from local airports. That’s often right around the sweet spot for sky color. Colors are created as the last rays of the sun light up the ice crystals in clouds aloft. While colors can happen before, during or after sunset, tropical sunset displays tend to peak as many as tens of minutes after sunset because the clouds are so high up.

Why the amazing colors? Something called Rayleigh scattering. It’s the same reason the sky is blue during the midday and yellowish in the evening.

2010: Hurricane Earl’s sunset sequence

“To produce vivid sunset colors, a cloud must be high enough to intercept ‘unadulterated’ sunlight … i.e., light that has not suffered attenuation and/or color loss by passing through the atmospheric boundary layer,” wrote former Storm Prediction Center meteorologist Stephen Corfidi. “This largely explains why spectacular shades of scarlet, orange, and red most often grace cirrus and altocumulus layers, but only rarely low clouds such as stratus or stratocumulus.”

Although these conditions can occur during any evening or morning with the right conditions, the easiest forecast for such magnificent skies often comes when a tropical cyclone is approaching. So next time you see the sky turning milky with a named or unnamed tropical system nearby, plan to take a look upward as the sun moves behind the horizon.

See below for more pictures by Capital Weather Gang readers.

The beautiful sunset also stretched up and down the East Coast.

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