I had to think about the 22 degrees size of the halo for a minute before I remembered that the distance between two points in the sky can be expressed in terms of azimuth (the width of your outstretched fist is about 10 degrees). Need more coffee.
Yah, I've been watching the weather. No rain in sight. I do remember.... 2005? being on the phone with my brother and looking up at night and seeing the biggest, densest, brightest ring ever. I remember being startled and blurting out 'Holy Cow!' or something along that line. We had a huge storm about 5 days later, then the 154 fell down. Then the next storm Old San Marcos had a massive slide. We were forced to either drive E. Camino Cielo down Gibraltar to get to town, or drive up to Santa Ynez and come down the 101.
From the atoptics site:
"Does it foretell of rain? Not necessarily. High cirrostratus cloud forms the halo and this same cloud can be on the advancing edge of a warm front with its associated heavy rain. If a wind stirs from the south west, the sky becomes hazy, a halo forms around the sun which is then dimmed and finally obscured by increasingly thick cloud then rain is likely within a few hours. But very many halos are not associated with frontal systems and to see one is not at all a reliable sign of wet weather. "
9 Comments
-
1
-
-
Dec 02, 2020 10:25 AMI had to think about the 22 degrees size of the halo for a minute before I remembered that the distance between two points in the sky can be expressed in terms of azimuth (the width of your outstretched fist is about 10 degrees). Need more coffee.
-
2
-
-
Nov 30, 2020 06:53 PMYah, I've been watching the weather. No rain in sight. I do remember.... 2005? being on the phone with my brother and looking up at night and seeing the biggest, densest, brightest ring ever. I remember being startled and blurting out 'Holy Cow!' or something along that line. We had a huge storm about 5 days later, then the 154 fell down. Then the next storm Old San Marcos had a massive slide. We were forced to either drive E. Camino Cielo down Gibraltar to get to town, or drive up to Santa Ynez and come down the 101.
-
-
-
Nov 30, 2020 06:25 PMNo rain in sight
-
-
-
Nov 30, 2020 06:04 PMFarmer's Almanac used this to predict rain.
https://www.farmersalmanac.com/ring-around-the-moon-9657
-
-
-
Nov 30, 2020 06:35 PMFrom the atoptics site:
"Does it foretell of rain? Not necessarily. High cirrostratus cloud forms the halo and this same cloud can be on the advancing edge of a warm front with its associated heavy rain. If a wind stirs from the south west, the sky becomes hazy, a halo forms around the sun which is then dimmed and finally obscured by increasingly thick cloud then rain is likely within a few hours. But very many halos are not associated with frontal systems and to see one is not at all a reliable sign of wet weather. "
-
1
-
-
Nov 30, 2020 04:23 PMI've always associated that with incoming rain.... days or a week out depending on how far out the ring is.
-
-
-
Dec 01, 2020 02:14 AMThanks Mac, as always for your scientific and precise description of things ! (beats the old "almanac's folk stories ..)
-
-
-
Nov 30, 2020 06:30 PMThe lunar halo is always 22 degrees in radius. There is a very rare 46 degree halo that may appear around the Sun.
-
2
-
1
-
Nov 30, 2020 02:53 PMThat's the classic 22 degree lunar halo caused by refractive ice crystals high in our atmosphere.
http://www.atoptics.co.uk/halo/circmoon.htm