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Note: Temperature anomalies are relative to the 1985 to 2012 average; Data: National Oceanic and Atmospheric Administration; Map: Chris Canipe/Axios

Odds favor a return this year of the climate phenomenon known as El Niño — above-average sea surface temperatures in the equatorial tropical Pacific Ocean and related changes in weather patterns.

Why it matters: Depending on their intensity and exact location, El Niño events can alter global weather patterns — favoring above average precipitation in the parched state of California, for example, while inducing drought elsewhere. Typically, such events develop sometime in late summer or early fall, and peak during the winter.

Such events also can provide a natural pulse of heat released from the ocean to the atmosphere, boosting the odds that 2018 and possibly 2019 could be among the top five warmest years on record.

The big picture: The last El Niño event took place in 2015 and 2016, and it was one of the strongest on record. Michelle L’Heureux, a meteorologist at NOAA's Climate Prediction Center in Maryland, tells Axios that the upcoming event — which has about a 70% likelihood of occurring by the upcoming winter — is unlikely to be as potent.

"If something forms it’s likely to be on the weaker side of things," she said. "In general, weaker events tend to be a bit tougher to predict than stronger events.”

For signs of El Niño, scientists like L'Heureux look at sea surface temperatures in specific parts of the tropical Pacific, known as El Niño regions. These are the boxed areas on the sea surface temperature chart. In recent weeks, ocean temperatures have increased in parts of these areas.

But the formation of El Niño is a complicated dance between air and sea, and now, L'Heureux says, it's the atmosphere's turn to alter trade winds in a way that reinforces the changes in the water. These air and ocean feedbacks are what really get an El Niño going.

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Trump commutes Roger Stone's sentence

Roger Stone arriving at his sentencing hearing on Feb. 20. Photo: Drew Angerer/Getty Images

President Trump on Friday evening commuted the sentence of his longtime associate Roger Stone, according to two senior administration officials. Stone in February was sentenced to 40 months in prison for crimes including obstruction, witness tampering and making false statements to Congress.

Why it matters: The controversial move brings an abrupt end to the possibility of Stone spending time behind bars. He had been scheduled to report to prison on July 14.

Updated 10 hours ago - Health

Which states have set single-day coronavirus records this week

Data: COVID Tracking Project and state health department data compiled by Axios; Map: Danielle Alberti and Naema Ahmed/Axios

13 states this week surpassed records set just last week for their highest number of coronavirus infections in a single day, according to the COVID Tracking Project and state health department data. 16 states in total reported new highs.

The big picture: The United States' alarming rise in coronavirus cases isn't just due to increased testing — particularly where the number of cases has grown fastest over the last month, Axios' Andrew Witherspoon and Caitlin Owens report.

Updated 10 hours ago - Politics & Policy

Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Global: Total confirmed cases as of 6:30 p.m. ET: 12,389,660 — Total deaths: 557,279 — Total recoveries — 6,830,596Map.
  2. U.S.: Total confirmed cases as of 6:30 p.m. ET: 3,169,611 — Total deaths: 133,885 — Total recoveries: 983,185 — Total tested: 38,856,341Map.
  3. Public health: The reality of the coronavirus bites.
  4. Trade: Trump says he's no longer considering phase-two trade deal with China because the pandemic damaged the two countries' relationship.
  5. 🎧 Podcast: Rural America has its own coronavirus problem.