Stunning Light Pillars Light Up A Cold Vermont Night

The National Weather Service office in South Burlington
Friday posted this incredible photo of light pillars
at Jay Peak Resort. Cold, calm weather helps
create this relatively rare phenomenon.

 The National Weather Service office in South Burlington on Friday posted a spectacular photo of light pillars before dawn Friday at the Jay Peak Resort.   

As you can see in the photo, street and parking lights, outdoor security lights and such formed narrow, towering beams of light that looked like a strange impressionist painting.  It looked like some sort of freaky laser light show.

So why did ordinary outdoor lights go haywire on a chilly December pre-dawn?

The lights were fine and working as designed. It turns out a certain type of ice crystal that forms on very cold nights created this relatively rare phenomenon. 

 According to Science ABC:

"These plates of ice crystals orient themselves hexagonally as they drift down through the atmosphere. Their collective surfaces act like a giant mirror that reflects the light falling on them. The light being reflected will extend to a certain distance both above and below the light source. The denser and larger the ice crystals, the more pronounced this effect becomes.

The angle of the ice crystal surfaces will deviate a few degrees from the horizontal orientation, which causes the light pillar, as it elongates the reflection of light. Thus, these phenomena usually appear as columns of lights to an observer."

We get lots of cold nights in Vermont during the winter. As you've guessed, this type of cool light display can only happen under certain conditions. First of all, winds need to be pretty much calm. Wind would disrupt the reflection of light. 

Usually, cold air is pretty dry, but it does contain some moisture, certainly enough for the ice crystals to form. To help with the moisture supply, there was a temperature inversion over Vermont early Friday. 

The inversion, in which a layer of warm air rests atop cold, dense air near the surface, forms a lid.  Moisture from the ground, exhaust from chimneys and cars, and evaporation from rivers and streams probably added to the moisture content of the air. 

Light pillars were also seen elsewhere in Vermont Thursday night and Friday morning. Some spectacular ones were spotted in Barre, for instance. 

Most winter nights don't feature light pillars. But if you want to try hunting then down, they're most likely well after sunset, and often in the pre-dawn hours when winds are lightest.

 

Be On The Lookout For Rare Noctilucent Clouds.

Meteorologists at the National Weather Service office
in Seattle, Washington took this photo of beautiful,
eerie and rare noctilucent clouds last week

 If skies are clear enough for the next few nights, take a look toward the north after dark. 

There's been an outbreak of rare noctilucent clouds, an eerie, beautiful blue glowing wispy cloud that is as high in the atmosphere as you can get. 

They're most likely to be seen near the poles in the summer. In early summer, they're sometimes visible in places like northwestern England, Canada, Alaska, that sort of thing.  Sometimes people in the northern United States get to see them. This year, they've been the most pronounced in decades.

Here's how the Washington Post explains these clouds:

"Noctilucent clouds, also known as polar mesopheric clouds, appear during the summertime in each hemisphere at about 50 miles high in the layer of the atmosphere knows as the mesosphere. They form when water vapor congregates around specks of meteor dust floating in the mesosphere and freezes, forming ice crystals."

They're usually visible not long after sunset and before sunrise. The clouds are so high up they are illuminated by the sun that has, at ground level slipped below the horizon. It looks like it might be clear enough tonight to go out and take a look toward the north,  just in case these clouds appear.

The Washington Post said there's a clear reason why this has been such a good year for noctilucent clouds. The mesosphere is an incredibly cold, dry place. There's little moisture up there to work with. But for some reason, at least by the standards of the mesosphere, it's wet up there. 

Another shot of the noctilucent clouds over Washington
State last week taken by NWS personnel.

Nobody is sure why. Perhaps it's rocket launches. There were 16 launches in June. It could have been the It could have been the huge Hunga Tonga volcano eruption back on January 15, which put a remarkable amount of stuff high in the atmosphere. The eruption could have dragged some moisture from the Earth's surface way up to the mesosphere.  It's so high up that I doubt climate change has anything to do with the increase in these clouds. 

Sky watchers are certainly excited about these clouds now.  Last week, the National Weather Service office in Seattle, Washington urgently tweeted that anyone who was awake at that late hour should head outdoors to see what they regarded as the best display of noctilucent clouds in decades. 

They had the photos to prove it, too. Other spectacular sightings of these clouds have been reported this past week over places like British Columbia, Denmark and Great Britain.

This won't last long.  As the days slowly start to get shorter, the chances of seeing these beautiful clouds begins to diminish. 

The Maine Ice Disk Is Back!

The Westbrook, Maine ice disc is back on the Presumpscot
River. A similar ice disc caused a stir three years ago. 

 The famous, and very cool ice disk in a Maine river appears to be back.  

Officials in Westbrook, Maine Tuesday posted photos on Facebook of a thin disk of ice forming on the Presumpscot River during the cold snap that has afflicted New England, reports the Portland Press Herald. 

A large ice disc formed in the river at downtown Westbrook in January 2019, capturing international attention.

Ice disks, which are fairly rarely seen, result from a combination of river currents and circulations beneath the ice. As river ice starts to spin at these locations, they are shaped by other chunks of ice into perfect spheres.

The Westbrook disc in 2019, and the one forming now are larger than most ice disks.   The formation in 2019 also lasted an unusually long time - two weeks.  It captured international attention and became a tourist attraction, which boosted usually slow winter business in downtown Westbrook, the Press Herald noted. 

It's unclear how long the new Westbrook ice disc will last. It depends on whether there are thaws, or deeper freezes, or fluctuations in the levels of the Presumpscot River. 

As of Wednesday morning, the City of Westbrook reported in its Facebook page that the disc was still there, but had at least temporarily stopped rotating as a cold overnight apparently froze it to surrounding ice. 

Ice discs have been observed since at least the late 1800s.  They have been seen in Vermont from time to time, mostly recently on the Browns River in Jericho last winter.