Category Archives: Weather & Sky

Seen This Week: Shorter Days

Sunrise on Thursday 14 October 2021 (photo by Kate St. John)

16 October 2021

It’s been three and a half weeks since the September equinox and every day is shorter than the last. Sunrise draws attention because it’s later every day. On Thursday the sky turned red before the sun appeared.

In the half light after sunset Morela prepared to roost.

Morela is ready to leave for her roost, 13 October 2021, 6:59pm (photo from the National Aviary snapshot cam at Univ of Pittsburgh)

The days are the same length as in late February during peregrine courtship. Morela and Ecco visited the nest as if they are thinking of spring.

Morela and Ecco bowing, 13 October 2021, 6:14pm (photo from the National Aviary snapshot cam at Univ of Pittsburgh)

Meanwhile most plants and trees have set fruit, including this streetside Callery pear.

Callery pear fruit, 14 October 2021 (photo by Kate St. John)

And in Downtown Pittsburgh I found a directional message on our tallest building.

“There is the sky, so that must be Up.”

There is the sky so that must be Up, Downtown Pittsburgh, 13 October 2021 (photo by Kate St. John)

(photos by Kate St. John)

Foggy Morning

Fog on spider webs (photo by Kate St. John)

5 October 2021, 8:45am

It’s foggy this morning in Pittsburgh as it has been for several days. On Saturday, heavy dew gleamed at Frick Park and laced the spider webs with beads of moisture.

Foggy morning with dew at Frick Park, 2 October 2021 (photo by Kate St. John)

Today the temperature is warm enough under the trees that there is no fog beneath them though there is plenty above.

Foggy morning in Pittsburgh; no fog beneath the trees, 5 October 2021 (photo by Kate St. John)

On Friday at Schenley Park we could see at ground level but fog above the trees made the sun look like a moon under the arch of the Panther Hollow Bridge.

Sun rising in fog just below the Panther Hollow Bridge, Schnley Park, 1 October 2021 (photo by Kate St. John)

When the fog cleared, the Cathedral of Learning emerged as from a magical kingdom.

Fog clearing in front of the Cathedral of Learning, 1 October 2021 (photo by Kate St. John

Today the fog has intensified in the last hour, no birds are stirring in the trees and Ecco is waiting at the Cathedral of Learning to start his day.

Ecco waits at the green perch, 5 October 2021 (photo from the National Aviary snapshot camera at Univ of Pittsburgh)

(photos by Kate St. John & from the National Aviary snapshot camera at Univ of Pittsburgh)

Violent Storms Like Mountains in the Sky

F5 tornado in Elie, Manitoba, 22 June 2007 (photo from Wikimedia Commons)

27 Sep 2021

Tornado forecasting is better than it used to be but we always want earlier warnings and better accuracy. Now, thanks to computer modeling, “scientists have identified a key feature of big storms that could make such extreme weather events easier to predict.” The feature is a wispy cloud in the stratosphere called an above-anvil cirrus plume that is visible by satellite.

When most storms form they stay in the troposphere, the layer of the atmosphere where the majority of our planet’s weather takes place. But occasionally, they “punch up” into the stratosphere, creating mountains of clouds that trail wispy formations called above-anvil cirrus plumes (AACPs). These high-flying clouds have been linked to high winds, hailstorms, and tornadoes on the ground.

— Science Magazine: Supercell storms act like atmospheric mountains

These special clouds are on the downwind side of the supercell and are visible 10-30 minutes before the next stage in tornado formation.

Above-anvil cirrus plume is high above the tornado’s anvil formation seen from the ground (screenshot from Science Magazine video)

Modeling indicates they form for the same reason as banner clouds on the leeward side of isolated mountains. Here’s an example at the Matterhorn.

Banner cloud off the Matterhorn (photo by Zacharie Grossen via Wikimedia Commons)

See why violent storms are like mountains in stratosphere in the video below. Read more in Science Magazine.

p.s. Sometimes anvil clouds simply dissipate. That’s what happened to this cloud after sunrise in Pittsburgh on 18 September 2021.

Anvil cloud at dawn in Pittsburgh, 18 Sep 2021 (photo by Kate St. John)

(photos from Wikimedia Commons, Kate St. John, AACP screenshot from Science Magazine video)

Fall Is Here

Misty walk at Panther Hollow Lake, Schenley Park, 10 Sep 2021 (photo by Kate St. John)

11 September 2021

The weather has been pleasant with low humidity and highs in the 70s. Chilly fall mornings produce a mist on Panther Hollow Lake.

Asters are blooming right on time …

Asters (photo by Kate St. John)

… but this hawthorn tree is confused, opening two flowers and a leaf in September.

Hawthorn tree puts out two flowers and a leaf, Schenley Park, 10 September 2021 (photo by Kate St. John)

This eastern screech-owl confirms it’s fall when he peeks from his well known roost on 4 September. Though screech-owls breed in Schenley Park, they only use this roost during the non-breeding season.

Eastern screech-owl at the winter roost, Schenley Park, 4 Sep 2021 (photo by Kate St. John)

My least favorite hot weather will return tomorrow through Tuesday, forewarned by this morning’s red sunrise.

Red sky at morn, sailors forewarn.

Sunrise in Oakland, Pittsburgh, 11 Sep 2021 (photo by Kate St. John)

(photos by Kate St. John)

Any Day with a Crow in it is Full of Promise

Sunrise on 15 August 2021 (photo by Kate St. John)

21 August 2021

Any day with a crow in it is full of promise.

Crows: Encounters with the Wise Guys, by Candace Savage

Pittsburgh’s crows have finished breeding so the local families now gather in a communal roost. Last week I counted 100 of them, mostly fish crows, congregating at dusk on Ascension Church’s knobby towers, then they flew west to roost beyond the VA Hospital.

Crows congregating on Ascension Church towers, 22 Aug 2021 (photo by Kate St. John)

Last month they congregated long before sunset near the Cathedral of Learning but they’ve been warned not to do that. On 29 July a peregrine chased the pre-roost flock out of Oakland. I watched her repeatedly dive-bomb them, harass an individual low-flying crow, and push the flock east into the trees in Shadyside. As soon as they had settled far away, Morela flew back to the Cathedral of Learning.

The crows still fly west into the sunset and east into the sunrise but now they give the Cathedral of Learning peregrines a wide berth.

Sunrise with three crows heading east, 15 August 2021 (photo by Kate St. John)

(photos by Kate St. John)

What About That Lightning?

Lightning in Dallas, 2015 (photo from NOAA Weather in Focus Photo Contest via Wikimedia Commons)

19 August 2021

Curious about lightning? Today’s article is a scavenger hunt for lightning facts. Two vintage blog posts provide the answers.

Looking Forward to a Little Less Lightning (click the link) will tell you …

  • Which month produces the most lightning in Pittsburgh?
  • If a person is struck by lightning what’s their percentage change of surviving it?
  • Who holds the world record for being struck by lightning? How many times was he hit? Did it eventually kill him? And a much longer story about him here.

In Why Does Thunder Rumble? you’ll find out:

  • How long is a lightning bolt?
  • How far away is that lightning? Plus an easy technique for answering this question.
  • (And of course) Why does thunder rumble?

And a bonus! Here’s a 10 minute video of lightning in slow motion recorded in Singapore by The Slow Mo Guys. (I’ve skipped the video forward to just before the lightning starts.)

(photo from Wikimedia Commons; click on the caption to see the original)

In Tidewater Virginia

Sunrise over the Pagan River, 15 July 2021 (photo by Kate St. John)

17 July 2021

This week my husband and I have been visiting family in Tidewater Virginia, our first long trip since the COVID-19 shutdown. Everyone’s vaccinated (& some had COVID last winter) so at last we’re making the “Real Hugs Tour.”

It is hot. 92 degrees F near the water, 100 degrees on the roads in the interior. Every morning I take a walk before it gets too unpleasant.

At the ocean I was pleased to see saltwater birds and southern songbird species. Favorite birds on the bay side of First Landing State Park were least, royal and sandwich terns plus a blue grosbeak (eBird checklist here).

View of the bay from First Landing State Park, 14 July 2021 (photo by Kate St. John)

I also encountered a lot of bug sounds …

… and a dragonfly that repeatedly perched on a twig in the stiff wind. Its behavior reminded me of a kestrel.

Dragonfly holding onto a twig in a stiff wind, 14 July 2021 (photo by Kate St. John)

The landscape is beautiful and welcoming until you stand in the sun.

Low tide at Windsor Castle Park, Smithfield, Virginia, 16 July 2021 (photo by Kate St. John)

Blackberries ripen in the heat.

Blackberries, Smithfield, 16 July 2021 (photo by Kate St. John)

House finches are prolific breeders in the hanging baskets on my sisters porch. This brood froze as we peeked under the fern in one basket while another house finch couple was building a new nest in the next basket.

House finch nestlings in a hanging basket, 15 July 2021 (photo by Kate St. John)

In Pittsburgh it is 10-15 degrees cooler but we will miss the sea breeze when we get home tomorrow.

(photos by Kate St. John)

Flash Floods Every Day

Flash floods on Nine Mile Run last week left flood debris up to my ears! (photo by Kate St. John taken on 10 July 2021)

11 July 2021

Southwestern Pennsylvania has always been prone to flash floods but last week was exceptional with a flash flood every day, three days in a row.

At 3pm on Wednesday 7 Jul 2021 a heavy downpour in the Nine Mile Run watershed caused a flash flood recorded by Upstream Pittsburgh‘s stream cam (video below, blurry because it’s raining). The downpour was so localized to the East End that it did not register on Pittsburgh’s official weather gauges. Flood debris showed that if I’d been on the Nine Mile Run Trail the water would have been up to my ears! (photo at top taken at 40.4263341,-79.9068387).

07 July 2021 Storm Timelapse at Nine Mile Run from Aaron Birdy on Vimeo.

On Thursday 8 July at 7pm a downpour over Pleasant Hills had devastating results as reported by CBS Pittsburgh.

video from CBS Pittsburgh on YouTube

And on Friday 9 July another localized thunderstorm let loose for half an hour in Squirrel Hill. I have no photos because I was driving down Braddock Avenue in the downpour, hoping the river on the road would not become a car-swallowing lake under the Parkway bridge. Fortunately the water ran off into Nine Mile Run. Another flash flood. I’m glad I was not on the trail.

As crazy as this is, it should not be a surprise. Pittsburgh is prone to flash floods, especially in Allegheny County as shown in the 35-year map of Flash Flood Reports from the National Weather Service.

Number of flash floods in 35 years by county, 1986-2020, in NWS Pittsburgh forecast area (image from NWS Pittsburgh)

We don’t need a particularly wet year for this to happen. Pittsburgh’s 2021 rainfall is actually 0.93 inches below normal as of today. The problem is that the rain falls all at once, especially in June and July.

Climate change is making the problem worse. A 2019 study found that extreme precipitation has increased 55% in the Northeastern US in my lifetime.

Heavy rain has increased across most of the United States, 1986-2016 (map from climate.gov)

This trend will continue in southwestern PA through the 21st century. (Click here to see where frequent heavy downpours will increase in the U.S.)

Brace yourself, Pittsburgh, for a lot of flash floods in the future. Sometimes every day.

About Nine Mile Run per Upstream Pgh (formerly Nine Mile Run Watershed Association): “Nine Mile Run is a small stream that flows through Pittsburgh’s East End, mostly underground. The 7 square mile Nine Mile Run watershed is home to the largest urban stream restoration in the United States, completed by the U.S. Army Corps of Engineers in 2006.” Upstream Pgh got its start with this project and now works throughout the region on community-oriented stormwater management projects, large and small, plus much more. Click here for their website.

p.s. If you’re not from the area you might not realize that “Pgh” is an abbreviation for Pittsburgh. We’re the only Pittsburgh with an “h.”

(photo by Kate St. John, videos from Upstream Pittsburgh and CBS Pittsburgh, maps from NWS Pittsburgh an climate.gov; click on the captions to see the originals)

Enchanting Sky and Flowers

Sunrise on 24 June 2021 (photo by Kate St. John)

26 June 2021

The sky was enchanting on Thursday morning while enchanter’s nightshade (Circaea lutetiana or perhaps Circaea canadensis) was blooming in Schenley Park.

Enchanter’s nightshade, Schenley Park, 25 June 2021 (photo by Kate St. John)

On 16 June, six of us were enchanted by mountain laurel and hundreds of pitcher plants blooming at Spruce Bog on top of Laurel Mountain.

  • Mountain laurel on Laurel Mountain, 16 June 2021 (photo by Kate St. John)

In the slideshow above, notice the leaf that’s wrapped and sealed into a tube. The structure was made by an insect. I don’t know which one.

p.s. Read more here about the enchanter’s nightshade name. Interestingly the plant is not in the nightshade family.

(photos by Kate St. John)