Yesterday Nvidia lifted AI investors' spirits. Today came a warning about another side of the AI boom: Lock up your critical infrastructure — the cyberattacks are coming.

Zoom in: OpenAI, Anthropic and more than 100 other companies — ranging from AI companies and cloud providers to telecoms and financial firms — warn in an open letter that organizations now only have months to prepare, Axios' Sam Sabin writes.

They lay out a plan for how all companies and governments, as well as cybersecurity and AI companies, need to adapt to prepare for the changing threat landscape.

• Among the suggestions: "Raise the security bar for what you buy, build, and deploy, including AI-generated code."
• They implore cybersecurity and technology companies to quickly test and build out tools that make "AI-powered defense accessible and deployable for critical-infrastructure operators," among them hospitals and water treatment plants.

The big picture: The warning comes amid a wave of cyberattacks against critical infrastructure, including one that targeted U.S. water systems with an apparent AI-generated exploitation script.

• AI models are now drastically lowering how much time and energy hackers need to put into those preparations, experts previously told Axios.

Cybersecurity stocks, meanwhile, soared today.

• Okta closed up 28.6% after yesterday's earnings, where it said it closed dozens of new AI deals and highlighted its growing opportunity in securing the identities and access of AI agents.
• CrowdStrike rose 20.5%, projecting better-than-expected full-year revenue powered by risks from the AI boom. "We're in an arms race," CEO George Kurtz told investors. "The agent of today is both a friend and foe."

Go deeper

Several of America's most prominent retailers reported earnings today, providing a mixed look at consumer health.

💵 Zoom in: Dollar General and Dollar Tree both reported gains in customer traffic from the same period a year ago. And both saw gains in same-store sales, at 3.5% and 3.7%, respectively.

• Both dollar chains benefited from higher-income shoppers trading down.
• Consumers with more than $100,000 in income are increasingly shopping at Dollar General, CEO Todd Vasos said on an earnings call.
• Dollar Tree said it saw sales gains skewing to the middle- and higher-income households.

🏷️ Both companies defended their promotional and pricing strategies on earnings calls, citing strained consumers constantly on the hunt for value.

💻 Best Buy, meanwhile, posted enterprise comparable sales growth of 4.1%, sailing past S&P Capital IQ expectations of 1.6%. The company also raised its sales outlook.

• Yes, but: One thing worrying the market is the onslaught of higher electronics prices driven by memory chips. Incoming Best Buy CEO Jason Bonfig said the company is tracking "unit declines in the high single digits" due to memory price hikes.

👖 Gap announced a new CEO for Old Navy as the brand reported a drop in comparable sales. (CNBC)

⛳️ Golf equipment maker Callaway cut ties with Good Good after the YouTube brand made a controversial ad in which a golfer shoves a woman to the ground. (CNN)

⚽️ Joshua Kushner and his firm Thrive Capital are being pulled into the feud between soccer's two biggest governing bodies, as UEFA seeks documents from them for a possible criminal case against FIFA president Gianni Infantino over his failed plan to sell investors a stake in FIFA's commercial business. (WSJ)

Kalshi is partnering with the owner of the Weather Channel and Weather.com to exchange data on climate predictions and outcomes.

The big picture: Kalshi is looking to beef up the weather predictions component of its exchange, allowing users to risk money on precipitation and temperatures.

• The Weather Co. will provide data that will serve as outcome verification for Kalshi traders.
• And the Weather Channel app and site will incorporate Kalshi prediction market insights.

By the numbers: Kalshi said it's "pacing toward $1.1 billion in annualized volume as traders look to hedge weather risks or trade on shifting climate trends."

💭 Nathan's thought bubble: Prediction markets can serve as a hedging opportunity for businesses that are greatly affected by the weather — but the question is whether the societal benefits of hedging will outweigh the risks of users losing money on frivolous trades.