RECORD-SETTING NOCTILUCENT CLOUDS: If you’ve never seen a cloud of frosted meteor smoke, now is the time to look. 2019 is shaping up to be the best year for noctilucent clouds (NLCs) … maybe ever. Normally confined to near-Arctic latitudes, NLCs have been seen this month in most US states. On Friday morning, June 14th, Don Davis saw them, astonishingly, from the city of Joshua Tree not far from Los Angeles CA:
“They were dim but distinct,” says Davis. “I photographed them easily using a 4 second exposure at ISO 400.”
Davis’s sighting at +34.1 degrees sets the record for low-latitude observations of NLCs, breaking the previous record set only five days earlier by Brian Guyer at the National Weather Service in Albuquerque, New Mexico (+35.1 degrees).
“I’m shocked to report that I saw the noctilucent clouds while venturing outdoors for a weather observation shortly after sunset,” says Guyer, who is a senior meteorologist. “When I noticed the faint blue wavy tendrils far off to the north, I asked myself, ‘am I really seeing noctilucent clouds from here?’ I’m happy to see that other folks are also seeing these beautiful spectacles of nature at lower latitudes.”
Noctilucent clouds form every year when wisps of summertime water vapor rise to the top of Earth’s atmosphere and crystallize around specks of meteor smoke. The season typically starts in late May, peaks in July, and peters out in August. If NLCs are being seen in California and New Mexico in June, the season’s peak in early July could be very special indeed.
Noctilucent clouds have been creeping south for years–a possible result of climate change and/or the solar cycle. 2019 has broken all the old records for southern sightings, bringing the clouds into the mainstream of mid- to low-latitude sky watching. Now everyone should be alert for NLCs.
Observing tips: Look west 30 to 60 minutes after sunset (or before sunrise) when the sun is just below the horizon. If you see luminous blue-white tendrils spreading across the sky, you may have spotted a noctilucent cloud.