Wednesday, January 30, 2019

January Skies: Cold Fronts and Short Walks


On the road to full recovery...

Midnight dog walks of a mile or so, a few visits to the Gamelands flat 2 mile loop at Muddy Run, and a few miles every other day on the treadmill and I'm chomping at the bit to get going further and longer. No more walking boot or hard cast, nothing hurts, lots of stretching/yoga/PT. I'm soooo impatient! Lots of time to thin about what to make this year's hike theme, especially since I'll be sticking to flat trails and bike paths for a while.

Since I spent the better part of four months watching skies and birds from a window with my leg up, I decided to make this year's blog theme Year of the Sky. I'm dedicating this post to Louis Rubin, Sr., author of several great cloud and weather books. My favorite is The Weather Wizard's Cloud Book (1989) - it got me hooked on cloud watching and forecasting way back when I was in high school! Like a thousand years ago.


A cold front sweeps into Northern Maryland and Southern Pennsylvania on Tuesday, Jan. 8 

Cold fronts are much more dramatic compared to warm fronts and changing cloud formations signal  unsettled weather as they pass over. The following two days are windy and cold, but the day of its arrival packs a punch for cloud watchers. We've a bunch of strong cold fronts come through this month so observing the progression of events has been easy but the cold has been brutal.


Two hours after the cold front boundary passes over we had waves of Mammatus and bursts of sleet.

As the cold air sinks into the warm, moist air mass it's replacing, mamma clouds sometimes form. According to Rubin in Forecasting the Weather (1970) this is considered a rare cloud type when not found in association with a summer thunderhead so we were pretty jazzed to see this form at the interface of warm and cold air during a frontal system early in the month.  For an hour we had sporadic sleet and gusts of wind as these formations appeared and disappeared rapidly overhead.

Jan. 9 brings big winds and snow showers.


The next two days the winds howled out of the northwest! Snow showers fell from the dark, racing clouds overhead, but nothing accumulated. The winds were so strong that the snow seemed suspended in the air, hardly reaching the ground before it was swept up again in a rolling line of wind. We had short bursts of "diamond dust" as the cold air was so dry that snow particles could barely form.

Jan. 12 sunrise shows snow on the way!  

After a beautiful clear and breezy two days the sun rose on Jan. 12 for Saturday's Harford Bird Club Kids Winter Count at Swan Harbor Farm. The skies announced that more snow is on the way! Cirrus fibratus, very high ice clouds, merged with an icy blanket of Cirrostratus to give the sun the look of shining through frosted glass. By noon the sky was solid white under the approaching leading edges of a winter storm - our first accumulating snow of the new year. A week later, the cycle is set - a storm a week...


January 18 - Another winter storm approaches - written in sunset clouds and colors.

On Jan 19, a week later, while on a Friday night dog walk, I watched a huge ice halo, a lunar corona,  form around the moon. It's shifting colors and growing diameter indicated the depth of height and thickness of the cold air mass above us - soon to collide with a major Pacific storm system that has made its way across the country. Pretty cool to see! But very cold temps are on the way again- gale force winds down on the Chesapeake Bay, but no snow for us as the storm lifts to the north delivering a punch to Upstate New York and New England.

A lunar corona - storm on the way!

Climate change is no hoax. Intensity of storms has been increasing over the last decade and winter storms in particular are packing dangerous punches of frigid cold, high winds, and heavy precipitation as they draw lots of moisture off warm oceans and combine with cold fronts pushed southward by a destabilized Polar Vortex.  Louis Rubin was able to match the skies he observed and the weather they produced with patterns of volcanic ash distribution after major eruptions, thus making his predictions incredibly accurate for forecasting days of rain and fair weather - sometimes months ahead of time! It's very different now some sixty years later with many new factors to consider that Louis may not have even known about. Predicting has become a much more complex process than simply watching sunsets and cloud formations.

Jan. 20, 9am - Wild Geese Sky (Rest in Peace Mary Oliver) as rain is pushed out by an approaching cold front

In the course of four hours on Sunday morning, Jan 20, a heavy Pacific storm system laden with moisture coupled to a cold front crashed temperatures from the mid-40s F to the low-20s. While the creeks were fat and full with heavy rain runoff from the night before, alerts were posted for below-zero wind chills. Clouds were racing across the sky. Gale warnings were again posted for the Chesapeake. The skies seemed to blow apart as clouds swept out to sea. By sundown the sky was clear and the wind fierce.


Jan. 20, 12:30pm - The cold front arrives and temperatures plummet!

This was the night of the Blood Moon, a full lunar eclipse, and I was excited to get out and watch it. My dogs, however, had other plans and refused to take their late night walk. Coonhounds and very cold weather are not friends. I tried to go out by myself but they set about baying and hollering inside, incensed that I would even consider it. Oh well. We all snuggled in bed together and watched through the bedroom window. I hoped that my son, a nature photographer, would capture the scene where he lives. He did!


Photo credit: George Eppig @ George Eppig Photography 2019 (my son, the photographer).

The grand finale for the month arrived with a burst of snow and a roaring cold front on Jan 29-30. Most of the snow action happened at night but the sunset a few days before had set the stage for another weekly frontal system - but this time, the northern system was much bigger and stronger. The upper atmosphere was cooling very fast as a strong dip in the Polar Vortex was beginning to sweep from the Mid West to the Mid Atlantic and high cirrus clouds dusted the sky with ice and contrails at 35,000 feet and higher. I caught a post-sunset panorama of cirrus clouds on Jan 28 just twenty-four hours before the Big Chill descended. The ice particles scattered low sunlight across the sky in a yellow-to-purple optical show that lasted only a few seconds. Many photographers posted later that night on Facebook some amazing shots of "sundogs" and "rainbow streamers" - it was quite a show!


Jet contrails everywhere just below a tropospheric (30,000 feet +) layer of cirrus clouds.

Notes:

Louis Rubin, Sr. & Jim Duncan (1970/ 1989) The Weather Wizard's Cloud Book. This is the book that got me hooked on cloud watching. It's old and dog-eared at my house, but still in print and as popular now as it was a thousand years ago when I was in high school.