From the CEO of AAAS: “If this rule becomes final, Americans' hopes for future cures, national security and economic strength will rely on the scientific sensibilities of the nation's chief bureaucrat. Alzheimer's disease will not be cured by a budget analyst from either political party.”

More urban artifacts! @drshepherd2013.bsky.social

As a follow up to yesterday’s post. This graph uses a different index (rONI) which accounts for the warming climate baseline and the tropical ocean mean outside the El Niño region during each time period. Here we see the 2026 dynamical model forecast is still the highest, but much less so… 1/

Impressive! NOAA has modeled the recent CMEs, and impact could be in just over 24 hr from now! Tomorrow night (Thursday) we could see G3 / Kp 7 conditions and widespread auroral displays. Impact slated for 18 UT / 1 pm CDT June 4. Charge those batteries!

Spring (Mar-May) temperature departure from the 1991-2020 normal. Seems warm.

We're psyched to have @irenesans.bsky.social joining the @climateconnections.bsky.social team! More on Irene here: yaleclimateconnections.org/2026/05/intr...

With the beginning of the 2026 hurricane season comes a new face at the helm of Yale Climate Connections' hurricane season coverage: Irene Sans, who will be anchoring our coverage this year! Bob Henson and I will also continue to contribute. yaleclimateconnections.org/2026/06/2026...

HISTORIC EVENT IN SE ASIA Minimum 30.2 Sangley Point HOTTEST NIGHT EVER RECORDED IN THE PHILIPPINES Minimum 30.1 Manila HOTTEST NIGHT EVER IN MANILA INDONESIA Min 28.8 Manokwari Hottest night ever Philippines & Indonesia have broken records for over 1100 consecutive days!

Missed Casey's intro, so I was trying to remember the name of this group. It was right on the tip of my tongue, as it were. The Indexers? The Calculators? Then I remembered: Brenda and the Tabulations! #AT40

Fun fact: People often think the hurricane "cone of uncertainty" encompasses *all* potential storm locations. It's actually more like two-thirds. A new experimental cone bumps up the inclusion rate from 67% to 90%. @climateconnections.bsky.social yaleclimateconnections.org/2026/05/chec...

One of our policy folks tells us that letters to Congress are hugely important. They have a different impact than calls bc they can be passed around and so easily quoted. Some letters spark and change policy discussions. Submit yours for our walk team to hand-deliver: wclivestream.com/write

OK, here is a thing that happened on Tues 26 May 2026 at one of the longest-lived weather stations on planet Earth.

The world is no longer headed for the most catastrophic futures climate scenarios once warned about: but not because the science was wrong. It’s because people listened, and acted. Read on in this week's edition of Talking Climate.

Europe is indeed cooking in this late May—but so are parts of N Africa, E & S Asia, Central America, and S Florida. 100s of towns & cities have set record highs + record-warm lows for the month of May. My roundup: @climateconnections.bsky.social yaleclimateconnections.org/2026/05/west...

Scientists are already embarking on a pre-livestream walk this week, ahead of the smorgasbord of live talks set for next week. More in this thread on how scientists can sign up for talks, and how citizens can pitch in by writing letters of support.

Perhaps the fact that we are conducting an unprecedented experiment with the only home we have, by digging up and burning massive amounts of fossil fuels that is driving global change at rates 10X faster than the most recent warming of this magnitude that occurred oh about 55 million years ago? 🧐

Fantastic, pithy summary of the last 30 years of energy predictions and their pitfalls. Many of us recall "peak oil" and "renewables will never make it." (This doesn't mean we know nothing about where global energy is headed in the *long* term.)

As our political and physical climates both heat up, extreme temps can get overhyped in social media (e.g., heat indexes conveyed as actual temps). This one is the real thing: 94.6F in London. Daily UK temp records go back ~200 yrs at some sites, so 2C above *any* prior UK May temp is big indeed.

Prescribed burns and biomass removal saves $3.73 in economic damage for every dollar spent. www.science.org/doi/10.1126/...

Western Europe Bakes! Pink dots are all-time records for May. I count at 30, but there are many more. Temps 15°C+ (almost 30F) above normal. For some areas a heatwave this extreme this early is without precedent, but climate change makes it much more likely, more intense and longer lasting.. 1/

Every summer I repost this article on how to spot drowning. Please read it and pass on. In the last few years I’ve had SIX messages from people who saved a kid’s life after clicking on the link from my feed. slate.com/technology/2...

"The Family of Man" is one of Three Dog Night's most underrated songs, lMO. Also one of the few that gives each of the three lead vocalists one verse each. #AT40

Data centers making it hotter? New evidence more compelling than previous assertions. My thoughts www.forbes.com/sites/marsha...

While El Niño is expected to bring a quieter than usual Atlantic hurricane season, the reverse is true in the Pacific. I give a brief preview of the forecasts for the Pacific tropical cyclone season in today's post. yaleclimateconnections.org/2026/05/el-n...

With the prospect of a Strong El Niño arriving for peak Atlantic hurricane season (Aug / Sep / Oct (ASO)), here's what history tells us since 1950. Strong El Niño years have historically produced fewer storms, less active behavior, and fewer US landfalls. But the risk is NOT zero. Always be ready.

A 4-year-old girl died yesterday inside a hot vehicle. It's the third such death so far this year and we're just getting into the summer hot season. Back in 2024, I wrote this piece about why the number of children that die in hot cars seems stubbornly stuck. 🧪 (It was wrenching to write.)

Add hurricane seasons to the growing list of phenomena (tornado seasons, extreme rains) that climate change is tending to “clump” into more extreme intervals punctuated by quieter periods. Weather and climate weirding, if you will.

The latest in my 10-post series on hurricanes and climate change covers studies showing dramatic swings between active and inactive hurricane seasons are likely in the future, the risk of back-to-back hurricanes is growing, and hurricanes will likely get more damaging and deadly.

Mega-El Niño, bonkers El Niño, pick your superlative: We may have a big 'un arriving soon. But if so, does that mean the effects will be bigger? Or just more probable? Or does it "depend"? Answers to these and other Qs: @climateconnections.bsky.social yaleclimateconnections.org/2026/05/what...

We've seen a little bit of drought improvement in Louisiana, Mississippi, and Alabama compared to last week, but not much elsewhere. 99.00% of the southeast (AL, FL, GA, NC, SC, VA) remains in a moderate drought or worse, with 92.66% of the region in a severe drought or worse.

The monthly weather/climate summary for April highlights the the worst April drought conditions in contiguous U.S. history, the 6 billion-dollar U.S. weather disasters so far, and the usual list of global notable temperature extremes. yaleclimateconnections.org/2026/05/apri...

New summer outlook just dropped. This is the multi-model C3S ensemble forecast for June-August. Hope you like pain and suffering.

Gothic-pop body count: "The Night the Lights Went Out in Georgia": 3 "Dark Lady": 2 Although one of those three in "Georgia" s the one "that'll never be found." #AT40

Solid and thoughtful take from @dananuccitelli.bsky.social, including what's gone right and wrong since 2006: "...despite a few oversimplifications, the scientific descriptions in “An Inconvenient Truth” have largely withstood the test of time..." yaleclimateconnections.org/2026/05/a-lo...

🇪🇸 Spain's electricity in 2000: 56% fossil, 2% solar & wind. By 2026: 44% solar & wind, just 17% fossil. The crossover came in 2023. Gas now sets the price only 15% of the time vs 89% in Italy. More in my forthcoming Substack newsletter 👇 janrosenow.substack.com

An amazing article on the Tracy Arm mega-tsunami from last August. If this had happened at several different times during a 24-hour window, it would have resulted in the greatest loss of life in U.S. history. Instead, it is just a scientific curiosity.

After the 2023 marine heat wave, 70-75% “of our Caribbean sites had tipped from net growth into net erosion. They are now losing calcium carbonate faster than corals can add it. The threshold that earlier models had suggested might be crossed over during the next decade or so has already arrived.”

10”+ snowfall in Boulder thus far. Still snowing lightly at 9:30 AM 5/6/26. This is our latest-in-the-year 10”+ total since 23” on May 5-6, 1978, though we’ve had 8” amounts even later since then.

BTW: Fort Collins with 0.75" of precip since yesterday. Already some really beneficial rain/snow for northern Colorado. And we're just getting going

“Hot drought“ has become one of the key concepts in climate-change impact science with good reason…

Winter storm warning 8 PM Tues > 3 PM Wed for the CO urban corridor. Eye-popping stuff for May 5: "Heavy snow expected. Total snow accumulations between 4 and 8 inches with locally up to 12 inches near the foothills and across the Palmer Divide." mesonet.agron.iastate.edu/wx/afos/p.ph...

The imminent wet storm for the CO urban corridor is a godsend for drought relief. But there's real concern about tree limbs/power lines Tues night. Boulder and other snow-prone spots could get 6" or more on trees that leafed out 20+ days early. That much snow, on late-May-equivalent trees = ugh.

“Oversimplification is a major hallmark of pseudoscience. Where real scientists see complexity & uncertainty, pseudoscientists claim unnatural simplicity w/ unearned confidence.”🧪

I always think of "Only Yesterday" as the last Carpenters hit in their immortal "classic mode." It's kind of a pastiche of elements of their other greats (e.g., the "Goodbye to Love" electric guitar, the oboe under the verses), but it works beautifully on its own terms too. xoxox Karen #AT40

Post-Casey, you all might enjoy this parody of the lovely "Lovin' You" from the Canadian singer/comedian Shirley Gnome. Give it enough time to get to the delectable payoff. #AT40 www.youtube.com/watch?v=hlfX...

We are touching the stove (and getting singed…)

Great thread from @hausfath.bsky.social on the demise of the high-end emissions scenarios (RCP 8.5 and SSP 5-8.5) that are now well beyond 2020s-era "business as usual." Things aren't evolving as badly as we once though they might, but we're still in a situation fraught with all kinds of hazards.

The latest post on my ongoing series on global warming and hurricanes. Warming oceans should increase the risk of a major hurricane in the Northeast U.S., but climate change might cause slower-moving storms, which would get weaker as they cross the cold waters offshore of the Northeast.

It really does look more like mid-May than late April over much of the Central Great Plains from eastern CO to the Mississippi. In Boulder, lilac blooms that normally pop out in May have already come and gone.

Parts of six states across the MS/TN/OH valleys are included in this top-end tornado watch, extending to 11 PM CDT Mon 4/27. Multiple tornadoes of at least EF3 strength are possible, per the NWS Storm Prediction Center. Extremely unstable surface air is at hand (temps mid 80s, dew pts 70-75F).