Slight Severe Threat Today – 90s Return

I have tried to connect the dots between a warming climate and increasingly extreme weather events for nearly 25 years. This summer has been a sobering Exhibit A. Drought in Minnesota and 40 percent of the USA at last count. LA-size fires in Oregon and wildfire smoke stretching coast to coast. 121F in Lytton, British Columbia, leveled by fire less than 2 days later.

But nothing could prepare me for Zhengzhou, China, where 8 inches of rain fell in one HOUR, 24 inches (a year’s worth of rain) in 2 days. I’m seeing things I haven’t seen before and it’s getting harder to keep up.

Another surge of heat returns today and lingers next week with more 90s likely. A few T-storms may turn severe later today and tonight, but rain will be spotty over the next 1-2 weeks as waves of desert-like heat wash over Minnesota. 100 degrees is not out of the question just south and west of MSP next week.

Despite dribs and drabs of rain Minnesota’s drought continues to worsen; extreme drought now from Alexandria and Wadena to Bemidji.

July Rainfall To Date

Another Rainfall Deficit in July. After a dry June, July is trending just as dry with rainfall deficits of 2-3” across much of Minnesota. Since June 1 much of the state is running at 4-5” rainfall deficit. Unless a front or storm stalls nearby we won’t make up that kind of deficit anytime soon, and even then, any torrential rains would (mostly) run off into streets and streams. We need a series of soaking rains to take the edge off the drought.

Consistent 90s Into Next Week. I don’t see any significant relief until (maybe) the first week of August, when ECMWF brings a strong puff of cooler, Canadian air south of the border. Until then 90s will be the rule, not the exception.

NOAA NDFD Temperatures for MSP
ECMWF Temperatures for MSP
NOAA GFS Temperatures for MSP

No Sudden Pattern Shift Anytime Soon. With prevailing winds blowing from the desert southwest it will be hard to get a meaningful shift in our weather toward cooler/wetter looking out into mid-August. That said, the epicenter of heat may remain south of Minnesota into the first week of August.

A visitor took a picture of the dried up western falls at Gooseberry Falls State Park on Wednesday, July 21, 2021. Sections of the falls have dried out because of the drought that has plagued the Midwest this summer.
Alex Kormann, Star Tribune

Are Dry Gooseberry Falls a Sign of Some Bigger Problems? Star Tribune reports; here’s an excerpt: “…With most of Minnesota in a state of drought, the rushing waters of many of the region’s inland tributaries and rivers have slowed to a trickle, including the western side of the North Shore’s Gooseberry Falls. Its lower falls have run dry, offering a rare view of the famous waterway. While it’s not unusual for that side to dry up, it’s usually later in the summer, said Nick Hoffmann, assistant park manager for Gooseberry Falls State Park. Gooseberry River, which drains from the Gooseberry watershed, is flowing but at a lower rate. “If this dry weather continues, there is a possibility the falls could dry up in late August,” Hoffmann said, which hasn’t happened in about 15 years…”


30-Year Data: Biggest US Weather Killer is Extreme Heat. According to NOAA data, since 1991 an average of 138 Americans a year have died from excessive heat – more deaths than floods and tornadoes, the second and third leading cause of fatalities.

Around the Globe, A Summer of Extremes. Star Tribune and the LA Times summarize the crazy extremes around the planet: …“All of this was predicted in climate science decades ago,” said John P. Holdren, a professor of environmental policy at Harvard’s John F. Kennedy School of Government. “We only had to wait for the actual emergence in the last 15 to 20 years. Everything we worried about is happening, and it’s all happening at the high end of projections, even faster than the previous most pessimistic estimates.” Scientists and environmental activists are in a race to persuade the world to reduce greenhouse gas emissions by enough to prevent global temperatures from rising more than 1.5 degrees Celsius above preindustrial levels. Failure to do so could result in massive disruptions such as famine and widespread coastal flooding. Time is short: Global temperatures have already risen on average by 1.2 degrees Celsius since 1880…”

A traffic police officer guides residents to cross a flooded road with a rope during heavy rainfall in Zhengzhou, Henan province, China, on Tuesday.
China Daily via Reuters

Eight Inches in One Hour: How a Deadly Downpour Flooded Zhengzhou, China. I have never seen rainfall rates like this in my meteorological career, not even during hurricane landfalls. Here’s a clip from Capital Weather Gang: “…At least 25 people were killed in subway cars amid devastating flooding in eastern China on Tuesday. The city of Zhengzhou, the capital of Henan province and home to more than 10 million people, suffered an extreme downpour that proved the heaviest ever observed in China and among the most significant on record globally. A staggering 7.95 inches (201.9 millimeters) of rain came down between 4 p.m. and 5 p.m. Tuesday, one of many reports of significant to prolific rainfall that resulted in deaths and damage across east China. It contributed to a daily rain total that exceeded 24 inches in Zhengzhou. That is almost a year’s worth of precipitation; the city averages 25.4 inches annually...”

In this photo taken with a drone provided by the Bootleg Fire Incident Command, a pyrocumulus cloud, also known as a fire cloud, rises over the Bootleg Fire in southern Oregon on July 14.

From Fire Clouds to Fire Tornadoes, Here’s How Wildfires Can Create Their Own Weather. Here’s a clip from an explainer at Yahoo News: “…Pyrocumulus clouds – aka fire clouds – look like giant, dirty-colored thunderheads that sit atop a massive column of smoke from a wildfire. Often the top of the smoke column flattens into the shape of an anvil. Here’s how it happens: When air over the fire becomes superheated, it rises in a large column. As air with more moisture rises, it rushes up the smoke column into the atmosphere, and the moisture condenses into droplets. That’s what creates the “fire clouds” that look much like the thunderheads seen before a big thunderstorm…”

Heat Waves Are Dangerous. Isolation and Inequality Make Them Deadly. The Washington Post (paywall) reports; here’s an excerpt: “…The onslaught of heat in places that rarely see such high temperatures has pushed communities to the breaking point. Roads have buckled, and train cables have melted. Emergency departments were overwhelmed. Yet as officials assess the staggering toll of recent heat waves — at least 115 deaths in Oregon — they are realizing their social infrastructure is equally in need of repair. Long-standing inequities in housing and health care put the region’s poorest residents at greatest risk. Official warnings and government services didn’t reach those who most needed the help. Almost every victim of the heat wave died alone. “The deepest challenge is the intersection of the ecological crisis and the social justice crisis,” said sociologist Eric Klinenberg, an expert on climate disasters…”

Burning restrictions in affect for eastern portion of Roseau County and all of Beltrami, Cook, Koochiching, Lake, Lake of the Woods, and St. Louis counties, excluding tribal lands. Burning restrictions remain in effect for Cass, Crow Wing, Hubbard, Itasca, Morrison, Todd, and Wadena counties.
Minnesota DNR

Burning Restrictions Expand in Northern Minnesota. Here’s an excerpt from The Minnesota DNR: “To help ensure public safety and protect natural resources, burning restrictions are in effect for the eastern portion of Roseau County and all of Beltrami, Cass, Cook, Crow Wing, Hubbard, Itasca, Koochiching, Lake, Lake of the Woods, Morrison, St. Louis, Todd, and Wadena counties, excluding tribal lands.

Under the restrictions:

  • Only campfires in an established fire ring associated with a home, cabin, campground, or resort are allowed.
  • No campfires are allowed for dispersed, remote, or back country camping. Camp stoves are permitted.
  • No fireworks may be ignited on any public or private land outside city limits (check with your local community for any additional restrictions).
  • The state will not issue burning permits for brush or yard waste…”

Extreme flooding in Zhengzhou, China, on July 20, 2021, after over 25 inches of rain fell in 24 hours.
Image credit: UN Climate Change Twitter feed

Extreme Rainfall in China: Over 25 Inches Falls in 24 Hours, Leaving 33 Dead. Meteorologist Jeff Masters reports for Yale Climate Connections: “At least 33 people are dead and 8 missing in Zhengzhou, China, after a July 20 extreme rainfall event of nearly unimaginable intensity. Zhengzhou, a megacity of more than 10 million – and the world’s biggest manufacturing base for iPhones and a major hub for food production and heavy industry – recorded an astonishing 644.6 mm (25.38 inches) of rain in the 24 hours ending at 21Z July 20. This is literally more than a year’s worth of rain: Its average annual precipitation (1981-2010 climatology) is only 640.9 mm (25.24 inches). The disaster follows on the heels of the extreme rainfall event that killed more than 200 people in Germany and Belgium last week…”

Deadly Flooding In Zhengzhou, China After A Year Of Rain Falls In 3 Days: Climate Nexus has headlines and links: “More than two dozen people have been killed by catastrophic flash flooding in central China in recent days. At least a dozen people drowned in the subway in Zhengzhou, Henan province, and about 100,000 people have been evacuated. Social media videos showed extreme flooding that turned cars into bathtub toys — as well as the harrowing rescue of 150 children and teachers from a flooded kindergarten. The city was deluged by 24.3” (617.1mm) of rain — 96% of its annual average — in just three days from Saturday to Tuesday. The extreme rainfall, and the severe heatwaves that strained the province’s electrical grid just days prior, are both clear signals of the climate crisis, caused by the extraction and combustion of fossil fuels. “Such extreme weather events will likely become more frequent in the future,” Johnny Chan, a professor of atmospheric science at City University of Hong Kong, told Reuters.” (Reuters, New York Times $, Washington Post $, BBC, The Guardian, France24, Al Jazeera, Bloomberg $; Recent heatwaves: Bloomberg $; Climate Signals background: Extreme precipitation increase; Extreme heat and heatwaves)

John Taylor

Is Maryland Becoming the New Tornado Alley? Short answer: no. At least not yet, based on the data. Here’s a clip from a feature story at Baltimore Magazine: “…So is Maryland suddenly becoming the new Tornado Alley? The better question might be, does anyone remember these back-to-back twisters in Howard County? Or, the 11 tornadoes that Hurricane Isaias spawned across Southern Maryland and the Eastern Shore last August? Sure, many people will remember Hurricane Isabel in 2003—estimated damages came close to $1 billion in Maryland and Washington, D.C.—when images of Baltimoreans paddling around downtown made the news. But what about the rest of our extreme events? “We do have kind of a shared amnesia,” Halverson says. “I think it’s a coping mechanism. If it hasn’t hurt our house, our family, our brain pushes it back in our memory and we think, ‘Oh that stuff doesn’t happen here…’”

Poison Ivy Could Be Getting Itchier, Here’s Why. Oh great. Mental Floss has a post, here’s a clip: “…Researchers have been keeping an eye on how poison ivy is reacting to a shifting environment. In 2006, Duke and Harvard University scientists published a study in the Proceedings of the National Academy of Sciences demonstrating that poison ivy could double its usual size when there were increased amounts of carbon dioxide in the atmosphere. More CO2 helped the plant with photosynthesis and water usage; CO2 also prompted it to produce more urushiol, meaning it could prove substantially more irritating to human skin...”

.06” rain fell a MSP International Airport yesterday.

85 F. Twin Cities high on Thursday.

84 F. average high on July 22.

69 F. high on July 22, 2020.

July 23, 1987: The greatest deluge ever recorded begins in the Twin Cities, with 10 inches of rain in six hours at MSP airport.

FRIDAY: Sunny and hot. Severe storms late. Winds S 10-20. High: 95

SATURDAY: Sunny, breezy and hot. Winds: NW 10-20. Wake-up: 74. High: 92

SUNDAY: Blue sky, lake-worthy. Winds: W 5-10. Wake-p: 72. High: 92

MONDAY: Sticky, unsettled. Few T-storms. Winds: S 10-20. Wake-up: 71. High: 93

TUESDAY: Some sun, thunder potential. Winds: SW 8-13. Wake-up: 71. High: 94

WEDNESDAY: Hot and bothered, chance of thunder. Winds: SE 8-13. Wake-up: 73. High: 92

THURSDAY: Sunny and steamy. Winds: E 10-15. Wake-up: 74. High: 93

Climate Stories….

NOAA File Image

Scientists Are Worried By How Fast the Crisis Has Amplified Extreme Weather. Can current supercomputers hosting today’s climate models keep up with the rate of change and intensification of extreme weather events? Here’s an excerpt at “…Since the 1970s, scientists have predicted the extent to which the world would warm fairly accurately. What’s harder for their models to predict — even as computers get more and more powerful — is how intense the impact will be. Michael E. Mann, the director of the Earth System Science Center at Penn State University, told CNN the past few weeks have showed the limitation of climate change models. “There is an important factor with many of these events, including the recent ‘heat dome’ event out west, that the climate models don’t capture,” Mann said. “The models are underestimating the magnitude of the impact of climate change on extreme weather events.” In climate models, Mann explained, day-to-day weather is just noise. It looks a lot like chaos. It’s only the most extreme events that stand out as a clear signal…”

Another Week, Another Weather Tantrum: We Are Changing the Atmosphere and Global Weather Patterns. Dr. Jennifer Francis explains in a post at TheHill: “…Disproportionate northern warming means a smaller north-south temperature difference — the main force driving the meandering river of high-elevation winds known as the jet stream. As this temperature difference weakens, so do the westerly jet-stream winds. Slower winds and differential warming patterns have been linked with wavier jet-stream patterns that cause stagnant summer weather systems. Persistent hot, dry or rainy conditions can turn into the very extremes we’ve seen unfolding again and again in recent weeks — heatwaves, drought and flooding. Tropical storms may also be feeling the effects of slower steering winds, resulting in the devastating floods and destruction wrought by sluggish hurricanes like Harvey, Florence and Dorian...”

The New York Times

America in 2090: The Impact of Extreme Heat, in Maps. An Op-Ed at The New York Times (paywall) delves into the frequency and intensity of future heat, based on emission reductions; here’s an excerpt: “…Summers that seemed exceedingly hot 50 years ago are becoming much more commonplace. The extreme heat of that era — which had a chance of occurring of only one-tenth of 1 percent during the summer season — is now reached more than 20 percent of the time, according to calculations by the climate scientist James Hansen. That’s 200 times as often. And nights are warming faster than days, at nearly twice the rate. So much for relief. And though the deadly, intense heat that baked the Pacific Northwest and Western Canada recently was startling, extremely hot temperatures have struck elsewhere in recent years, in surprising places and with calamitous consequences…”

Frequency of occurrence of Northern Hemisphere land temperatures in 2009–2019 relative to the 1951–1980 average in green.
From Hansen and Sato (2020).

As Scientists Have Long Predicted, Warming is Making Heatwaves More Deadly. Yale Climate Connections reports; here’s an excerpt: “…Contributing to the World Weather Attribution project, 27 scientists worked around the clock for a week immediately after this extreme event to determine the role played by climate change. The team used published peer-reviewed methods, comparing numerous model simulations of two scenarios: the “world as it was” when the event occurred, and a counterfactual “world that might have been” had humans not altered Earth’s climate by burning fossil fuels over the past 150 years. The results are striking. The authors concluded that a heat event so extreme was “virtually impossible without human-caused climate change.” While it’s difficult to quantify the rarity of such unprecedented weather, their best estimate was that it was a 1-in-1,000-year event. Without human-caused climate change, such an extreme event would be at least 150 times rarer, and the heatwave was about 3.6°F hotter than it would have been naturally…”

Climate Central

A Warming Tokyo Hosts the Olympics. Here’s an excerpt from Climate Central: “Japan’s climate is warming due to climate change. And the added heat, on top of an already hot and muggy summertime climate, could make the 2021 Tokyo Olympics and Paralympics one of the hottest in modern times. Even the best athletes will be adversely affected by climate change. More intense heat, humidity, and poorer air quality could lead to heat-related illnesses and decreased performance. In hotter temperatures, certain sports, like the marathon, tennis, and the triathlon, can become dangerous. Factors that can increase heat risk include duration of play, intensity of play, surface of play (water vs. turf vs. blacktop), and more…”

From the 1950s into the 2010s (and continuing into the 2020s), no significant trend has emerged in the annual number of U.S. tornadoes rated EF1 or stronger.

Climate Change and Tornadoes: Any Connection? Bob Henson reports for Yale Climate Connections: “…Although the total yearly count of significant, EF1-or-stronger tornadoes (EF1+) hasn’t risen or fallen substantially or over a sustained period, how these tornadoes are distributed across time is another matter. The monthly variability of EF1+ tornadoes has increased since the 1970s, with a growing occurrence of both record-busy and record-calm months, according to a 2014 study. To cite a recent example, the count of 510 tornadoes of all strengths in May 2019 was more than 100 above any other May on record. Just two years later, May 2021 became the first May on record without a single EF3-or-stronger tornado (EF3+) anywhere in the United States…”

The aftermath of recent flooding in Bad Muenstereifel, Germany.
Wolfgang Rattay/Reuters

Catastrophic Floods Could Hit Europe Far More Often, Study Finds. Details via The Guardian: “Catastrophic floods such as those that struck Europe recently could become much more frequent as a result of global heating, researchers say. High-resolution computer models suggest that slow-moving storms could become 14 times more common over land by the end of the century in a worst-case scenario. The slower a storm moves, the more rain it dumps on a small area and the greater the risk of serious flooding. Researchers already knew that the higher air temperatures caused by the climate crisis mean the atmosphere can hold more moisture, which in turn has led to more extreme downpours. The latest analysis, however, is the first to assess the role of slow-moving storms in causing extreme downpours in Europe...”

As Disasters Spiral, Cities Confront Need for Climate Adaptation. Bloomberg CityLab + Green has the post; here’s the intro: “When record-shattering triple-digit temperatures hit the Pacific Northwest in late June, some scientists saw more than just an extraordinarily unusual heat wave amid the severe drought and wildfires already afflicting the Western U.S. this summer. Researchers with the group World Weather Attribution studied the event, which impacted nine million people, killed hundreds, and obliterated local heat records by as many as nine degrees, and determined it could be something of a landmark in the escalation of the climate crisis — a weather event so off the charts that it would have been statistically impossible in a world before human-caused climate change. As Dutch climate researcher Geert Jan van Oldenborgh put it during an episode of The Daily, “we could be past the threshold that made these kinds of heat waves certainly much more likely.” Weather extremes once expected to come in decades are occurring today. And too many cities are dangerously unprepared...”