Flagstaff’s February weather has been very active with rain and/or snow recorded on seven days out of the first fifteen. Several days of snow on the Kachina Peaks covered the trees with a thick coating of rime ice and lots of new snow on the slopes.
And then we had an “atmospheric river” that produced a significant amount of winter rain with about 1.5 inches falling in the Flagstaff area. The runoff in Oak Creek and its tributaries was impressive.
And the forecast for the next week or so is a continuation of stormy weather with lots of snow for the higher elevations. I believe the long-anticipated El Niño has finally arrived.
Comet C/2018 Y1 Iwamoto has just made its closest approach to Earth this week. With one evening of clear skies forecasted before the next storm system moves into the area, I went out earlier this week (02/11/2019) to capture images of this fast-moving, blue-green comet. The Moon was up in the western sky with 38% of the disk illuminated. This caused considerable brightening of the sky and made it challenging to capture fine details of the comet.
Discovered by Japanese amateur Masayuki Iwamoto as a +12th magnitude fuzzball moving through the constellation Hydra the Water Serpent on the night of December 18th, 2018, Y1 Iwamoto is a fast mover. It’s great to see that amateur astronomers can and still do discover comets, as the robotic competition posed by automated surveys such as PanSTARRS makes such an independent discovery tough these days…
At its closest on February 13th, Comet Y1 Iwamoto will appear to move seven degrees a day. This translates into a fast apparent motion of about 2/3rds the apparent diameter of a Full Moon, every hour.
The comet was easy to find with a pair of binoculars but was not visible to the unaided eye. Its position on this evening was near enough to the bright star Regulus that I had no trouble aligning the camera.
The following image and animation show the motion of the comet during a period of just over one hour.
Time lapse movie showing the motion of C/2018 Y1 during a period of one hour.
Comet C/2018 Y1 Iwamoto will make its next passage through the inner solar system in 3390 AD.
Over the weekend we had an extended period of rain in the Flagstaff area. Normally we would see snow at this time of year.—it is, after all, the middle of winter. Rainfall amounts were sufficient (1.35 inches at Flagstaff airport) to cause large increases in the flow of Oak Creek where gauges recorded a rise from ~2.4 feet (30 cfs) to 9.6 feet (6900 cfs). Other streams were running high as well.
I though it might be interesting to look at Lake Mary and Mormon Lake to see if lake levels were increasing as a result of the runoff. Indeed, they were, but not quite as much as I had hoped. Still, water rushing down Newman Canyon, a normally dry wash, into Upper Lake Mary was impressive.
Back in December 2004, we had a much bigger rain event. Lake Mary was frozen and the water rushing down the hillsides flowed across the top of the ice. The immense weight of the water caused the ice to break with thunderous booms. That is what I was hoping to experience. Didn’t happen because there was no ice this time.
My next stop was Mormon Lake. As I drove towards it the sun was able to break through the thinning clouds to my south. I took a quick look in the rear-view mirror to check for rainbows.
And, there it was. A winter rainbow in Flagstaff. Not rare, but certainly not common.
I have been looking forward to the recent Lunar eclipse (20 January 2019) since, well, the last one actually. During that eclipse, I shot images every three minutes while using an equatorial mount to track along with the stars. The results were good but there was some room for improvement. And that’s why I was looking forward to this event.
The weather had different plans for me. A stream of high-level tropical moisture was sitting right over Arizona all that day and most of the night. By late afternoon, the clouds were thick enough to partially obscure the sun. How was a darkened Moon going to shine through those clouds?
I could have just given up and stayed home but I was determined to at least try. I drove to Sedona to set up. Not because Sedona is a better place for viewing than Flagstaff but because Sedona is about 15 degrees warmer. And that matters.
I set up the tripod and then roughly aligned the iOptron Skytracker to where I made my best guess of the location of the star Polaris. Just as the umbral phase of the eclipse began, I was able to barely see Polaris through the thin clouds and completed the alignment of the tracker.
One of the things I learned last year was that three minutes was too large a time gap to make a smooth time-lapse video. My plan for this eclipse was to shoot at 1-minute intervals. But with the high clouds I realized that any time-lapse video was going to be challenging. So…3-minute intervals again. The clouds varied between fairly thick and mostly obscuring the moon to occasionally very thin allowing some lunar detail to be seen.
Here is a satellite image from GOES-16 showing the incredible stream of clouds moving across Arizona. I’m amazed that I got any photos at all!
I awoke before dawn on New Years Day and was greeted with clear skies and a crescent Moon with the planets Venus and Jupiter shining brightly in the eastern sky. I drove out towards Mormon Lake anticipating great—albeit very cold—conditions for some sunrise snow photographs. On the way to the lake I encountered low clouds and patchy fog and there was nothing to be seen upon my arrival. It was already too close to sunrise to head back north or west so my only option was to wait and hope.
I missed the sunrise but about 20 to 30 minutes later the clouds cleared and the San Francisco Peaks were amazing. Low clouds and fog remained around the base of the peaks.
As the sun rose higher the side-lit rime ice on the wild grasses (i.e., weeds) at the Mormon Lake Overlook began to glisten and glow.
Temperatures were hovering in the low single digits and I was cold after standing around for about an hour. Time for breakfast and hot coffee.
The next day we hiked into West Fork Oak Creek knowing that the trail would be snow packed and there would be a dozen water crossings on ice—hopefully solid enough to support us. After several days of below freezing high temperatures and near or sub-zero overnight temperatures we were hopeful for safe ice.
There are several locations where water drips down the cliffs even at these cold temperatures resulting in wonderful icicles and bizarre ice sculptures on the ground.
We hiked to the “end” of the trail where it enters a narrow, rock-walled section of canyon often called “The Subway.” This was our turnaround spot.
On the way up the canyon we had not run into any other hikers. What a treat!