Category Archives: Weather & Sky

Seen This Week: Sun and Unexpected Carbon

Early morning sun and fog at Duck Hollow, 25 November 2024 (photo by Kate St. John)

7 December 2024

This week the city received a light dusting of snow but the ground was not as beautiful as the sky. Two examples: Fog and sun at Duck Hollow before Thanksgiving, and a very red sunrise on 4 December.

Sunrise in Pittsburgh, 4 December 2024 (photo by Kate St. John)

What is this? An arrangement of black carbon.

Faulty oven creates black carbon, November 2024 (photo by Kate St. John)

These were the unexpected result of a faulty oven thermostat that carbonized the Thanksgiving biscuits. Fortunately that carbon is only skin deep. My niece cut off the bottoms. The tops were yummy.

Weather Hazards Surround Us

What does 24 inches of snow look like? This is Lake Effect Snow in 2004 (photo from Wikimedia Commons)

5 December 2024

Today’s regional weather map is a bright splash of color, none of it good.

Pittsburgh weather map, 5 Dec 2024, 6am from NWS
  • Blizzard warnings (red) –> add snow 12-20 inches + wind gusts to 60 mph
  • Winter Storm Warnings (pink) –> add snow (but less than 20″) + wind gusts 45-55 mph
  • Lake Effect Snow (green) –> snow bands drop 10-20 inches + wind gusts to 50 mph
  • Gale Warning (pale pink) –> Lake Erie winds 40-60 mph, waves 10-15 feet

All of the forecasted snow is falling on top of existing snow. The photo at top shows 24 inches, though not from this snowstorm.

What do birds do when the weather’s this bad? We found out in November 2014 when a nasty snowstorm hit Buffalo, NY.

It’s a good day to stay home.

Remembering November Tornadoes

Tornado in Pennville, IN, 5 Nov 2017 (photo from NWS courtesy Matt Leach)

14 November 2024

Seven years ago this month, on 5 November 2017, a cold front spawned 24 tornadoes as it passed over Illinois, Indiana, Ohio and Pennsylvania.

The one that hit Williamsfield, Ohio was documented by the National Weather Service in Pittsburgh.

Damage in Williamsfield, Ohio from 5 Nov 2017 tornado (photo from National Weather Service, Cleveland)
Damage in Williamsfield, Ohio from 5 Nov 2017 tornado (photo from National Weather Service, Cleveland)

The November outbreak was unusual for its location and intensity, described in this vintage article.

So far, this year’s November tornadoes are less numerous and are well south and west of here.

Seen Last Week: Frost, Fog and Fall Color

Frost in the valley at Duck Hollow, 28 Oct 2024 (photo by Kate St. John)

3 November 2024

Last week began with light morning frost but rose to 80°F on Halloween.

The colors were gorgeous at Duck Hollow on Monday …

Fall color and blue sky at Duck Hollow, 28 Oct 2024 (photo by Kate St. John)

… while tendrils of fog chased each other across the river.

Fog tendrils blow slowly across the Monongahela River at Duck Hollow, 28 Oct 2024 (video by Kate St. John)

These wisps were formed at the rivers edge as clear cold air passed over warm water. Sunbeams make this a poor quality video, below, but you can see the wisps starting near shore. (You might also hear a song sparrow chipping in the background.)

Fog forms at Duck Hollow, 28 Oct 2024 (video by Kate St. John)

Slanting light illuminated the trees at Schenley Park.

Fall color and slanting light in Schenley Park, 29 Oct 2024 (photo by Kate St. John)

A leaf-hidden cocoon reminded me why clearing out leaves is bad for insects. This insect will overwinter on a leaf in Frick Park and emerge as — perhaps — a butterfly or month next spring. Or it may become food for a bird this winter. The insect chain is broken where don’t leave the leaves.

Insect cocoon on a leaf at Frick Park, 30 Oct 2024 (photo by Kate St. John)

Making the Sun Set Earlier

Sunset times in Pittsburgh, late 2024 (photo by Kate St. John)

2 November 2024

Spring Forward, Fall Back. Daylight Saving Time ends tonight as our clocks turn back an hour. Tomorrow the sun will set an hour earlier. A lot of us will be grumpy. Some will be depressed.

Most Americans agree that changing the clocks is bad.

Numerous polls have found that most Americans believe that a standard time should be fixed and permanent—as many as 75% favor no longer changing clocks twice per year. One of the most common observations among researchers of varying backgrounds is that the change itself causes most of the negative effects, more so than either standard time or daylight saving time. Researchers have observed numerous ill effects of the annual transitions, including reduced worker productivity, increased heart attacks and strokes, increased medical errors, and increased traffic incidents.

Wikipedia: SP Act Debate

There are places that don’t participate in this dreaded exercise: Arizona, Hawaii, Puerto Rico and other U.S. island territories.

Map of Daylight Saving Time in U.S. from Wikimedia

But there is an area in northeastern Arizona of self-governed indigenous tribal land where part of it uses Daylight Saving Time (DST) and the center does not. The DST area is the Navajo Nation which spans three states and has chosen to use DST. The donut hole is the Hopi Reservation that uses Standard Time. Here’s a closer look.

If you drive from Tusayan, AZ to Tuba City to Ganado to Window Rock in March through October, you will change time zones seven times between Standard Time and DST. (Did I count correctly?) People who have to make that trip will be relieved that everyone is on Standard Time tomorrow.

Changing your clocks: Everything connected to the Internet — mobile phones, etc. — will change automatically at 2:00am Sunday. The rest of the clocks are up to us.

p.s. I wonder what happens to a cellphone on the trip from Tusayan to Window Rock during DST.

Emerging From The Deep

Youghiogheny River dam with lake at normal level (photo from 1993 via Wikimedia Commons)

1 November 2024

In 1944 the US Army Corp of Engineers completed a flood control dam across the Youghiogheny River that created a lake into Maryland. The project included a new bridge for US Route 40 because the Great Crossings Bridge at Somerfield would be submerged and so would the town’s low lying streets and buildings.

map of Youghiogheny River Lake and Recreational Area from USACE via Wikimedia

Normally the lake is full and beautiful. You would never know there was a bridge underneath it.

Beautiful Youghiogheny River Lake (photo from recreation.gov)

But this year a drought in the Youghiogheny watershed has lowered the lake so far that you can walk out on the old Great Crossings Bridge.

video embedded from CBS Pittsburgh on YouTube

This Google Map shows both bridges.

embedded Google Map showing submerged Great Crossings Bridge north of US Route 40

Pittsburgh is not in severe drought so it’s hard to understand how this lake could drop unless you know where the river comes from. The Youghiogheny is a north-flowing river with headwaters in the mountains of West Virginia and Maryland. Notice that the rest of the Monongahela river basin starts in West Virginia as well.

Monongahela River Basin, Youghiogheny highlighted (map from Wikimedia Commons)

The headwaters of both the Youghiogheny and Monongahela have been in drought since early July. At this point the drought is Extreme to Exceptional in western Maryland and West Virginia.

Northeastern US Drought Map, 29 Oct 2024 (map from US Drought Monitor at UNL)

Water levels have dropped in both rivers but the Monongahela cannot afford to get too low because it carries a lot of barge and boat traffic.

Barge moving downstream on the Monongahela River at Duck Hollow, 18 Sep 2023 (photo by John English)

However, there is water upstream to feed the Monongahela. Releases from Youghiogheny River Lake have, in part, kept the Mon navigable.

And so the old bridge emerges from the deep.

p.s. This isn’t the first time the old bridge has been exposed.

Seen This Week: Autumn Colors

Fall color of pawpaw leaves, Schenley, 25 Oct 2024 (photo by Kate St. John)

26 October 2024

Fall color is so spectacular in Pittsburgh this week that many of us have been snapping pictures everywhere we go. Here are just a few of the colorful leaves and trees I’ve seen in town.

Pawpaw leaves are turning bright yellow in Schenley Park while Virginia creeper is red along the Three Rivers Heritage bike trail at Herrs Island.

Virginia creeper at Herrs Island back channel, 22 Oct 2024 (photo by Kate St. John)

Sunlight reflecting on the water made rippling lights in the trees on 22 October. It was so warm you can hear crickets.

Ripples in the trees, 22 Oct 2024 (video by Kate St. John)

Yesterday in Schenley Park the trees were yellow or red depending on species.

Scene on the Upper Trail, 25 Oct 2024 (photo by Kate St. John)
Scene on the Serpentine, 25 Oct 2024 (photo by Kate St. John)

Not to be outdone by autumn leaves, the sky turned orange at sunrise on Saturday.

Sunrise, 25 Oct 2024 (photo by Kate St. John)

Sunrise is after 7am now. We’ll “fix” that next weekend when we turn the clocks back.

Northern Lights Last Night in Pittsburgh

Aurora borealis at North Park, Allegheny County PA, 10 Oct 2024, 10:15pm (photo by Steve Gosser)

11 October 2024

We usually don’t see the aurora borealis as far south as Pittsburgh but this year has been amazing. Last night was its third visit and perhaps the best.

Having missed the other two events I went to Schenley Park golf course last night from 8:30 to 9:00pm. Knowing it would only be visible in cellphone photos I took a lot of pictures. Obviously there is too much light pollution! You can count the stars on one hand in my photo. But the sky is pink.

Faint pink of the aurora borealis at Schenley Park, 10 Oct 2024, 8:45pm (photo by Kate St. John)

Steve Gosser went to Allegheny County’s North Park and waited a long time for the aurora to become intense. At 10:15pm he captured the red and green photo at top. Wow!

Dave Brooke went further afield to Armstrong County and waited past midnight. He captured this still photo and …

Aurora borealis, Armstrong County, PA, early hours of 11 Oct 2024 (photo by Dave Brooke)

… this timelapse video.

Aurora borealis, Armstrong County, 10-11 Oct 2024, embedded video by Dave Brooke on YouTube

Double wow!!

A good view of the northern lights comes down to location and patience … and a good camera.

p.s. Dave described his timelapse process in the video description, copied below:

October 11th 2024 saw a G4 Geomagnetic storm with a Kp:8. This timelapse was taken in Armstrong Co in Western PA starting around 9:30pm. It consists of 193, 10 second exposures with an interval of 5 seconds between each shot. They were taken with a Canon R5 and a Sigma 14-24mm Art lens at 14mm. The aperture was 2.8 and ISO 800. The sequence was rendered in LRTimelapse and outputted at 1/2 speed.

Description of video by Dave Brooke

Frequent Heavy Downpours Are Now a Way of Life

Rain splashing during a downpour (photo from Wikimedia Commons)

1 August 2024

On Tuesday 30 July after a period of abnormally dry weather Pittsburgh had a series of gully washers that scoured the creeks and greened up the grass. The downpours were sudden and stupendous. In just three brief episodes — fortunately spaced seven hours apart — we received 0.85″ of rain.

Ten years ago we were amazed by these episodes because they were so different from our usual slow, soaking rains. Back then the only place I’d experienced this weather prompted me to call it “Texas rain.” In 2014 climate.gov predicted an increase in heavy rain episodes on this map. Pittsburgh registered an uptick but not the worst.

OLD PREDICTION IN 2014. Heavy Rain Days in 2041-2070
Map predicting change in downpour frequency, 2040-2070 (map from NOAA Climate.gov)
Predicted Change in days of extreme rainfall in 2041-2070 compared to 1971-2000, Greenhouse gas higher emissions (map from climate.gov)

Five years later climate.gov revised their prediction and it was worse.

REVISED! PREDICTION IN 2019. Heavy Rain Days in Late 21st Century
Predicted Change in days of extreme rainfall in late 21st century compared to 1986-2016, Greenhouse gas higher emissions (map from climate.gov)

From climate.gov: Prepare for more downpours: Heavy rain has increased across most of the United States, and is likely to increase further.

The two maps are not “apples to apples.” On the 2019 map the prediction time frame is longer and change is expressed as a percentage rather than an absolute number of days.

However the map is scary and it lit a fire under Pittsburgh Water and Sewer Authority (PWSA) to fix the sewers now before things get worse. Since then they’ve been systematically digging up city streets to replace ancient storm sewer lines while Alcosan (sewage treatment) is implementing their EPA-approved plan to keep sewage out of the rivers.

We don’t need a prediction map to tell us it’s getting wetter in Pittsburgh. Frequent heavy downpours are now a way of life.

Read more — though 10 years old — in this vintage article:

If You Think Today is Hot …

Deep orange sky, hot sun (photo from Wikimedia Commons)

15 July 2024

Excessive heat from the western U.S. is now in the East and the next two days promise to be brutal.

Right now I’m in Tidewater Virginia where today’s high temperature will be 97°F and “feel like” 107°F. Just after dawn the turkey vultures warmed their wings in my sister’s backyard. I’m sure they know where and how to stay cool later today.

Turkey vultures wake up in Virginia before it’s hot (photo by Kate St. John)

We humans, however, are not always in control of our time and some humans are not as smart as turkey vultures so every newscast reminds us to be careful and stay cool.

Yes, today will be hot but tomorrow will be worse. There will be Extreme Heat even in the mountains of Pennsylvania and West Virginia.

Heat Risk map for 16 July 2024 zoomed in to Eastern U.S. (image from digital.weather.gov)

Fortunately Wednesday will bring relief. Watch the heat for 15-17July on these maps.