What Makes a 1-in-1000-Year Storm, Really? Some great context here from a story courtesy of Washington University in St. Louis: “…Global warming is increasing the frequency of extreme precipitation events, including those events known as 1-in-1,000-year storms or floods — storms that have a 0.1% chance of occurring in any given year. They are important in the design of infrastructure across the country. Yet frequency estimates for extreme storms are plagued by uncertainty. This fact undermines attempts to put a storm in proper context. In terms of labeling something as a 1,000-year event, how much uncertainty are we talking about? It depends, researchers said — based on the location of the storm and other factors…”
Map credit: “Daniel P. Huffman (map); Source: “Examining the Changes in the Spatial Manifestation and the Rate of Arrival of Large Tornado Outbreaks,” by Niloufar Nouri and Naresh Devineni, in Environmental Research Communications, Vol. 4; February 2022 (data)”
The New Tornado Alley Has Been Hyperactive This Year. More evidence that traditional “Tornado Alley” may in fact be shifting south and east. Here’s an excerpt from Scientific American: “…For decades, most of the largest outbreaks occurred across northeastern Texas, eastern Oklahoma, and western Arkansas and Missouri. But between 1989 and 2019, the focus shifted eastward by 400 to 500 miles, covering western Kentucky and Tennessee plus northern Mississippi and Alabama…Climate change is warming the Gulf of Mexico as well, and this can send generous amounts of water vapor into the southeastern U.S.—farther east than it tended to travel decades ago. In addition, climate change has moved the rough north-south boundary between dry western U.S. air and moist, eastern U.S. air about 140 miles to the east…”
Global Sea Levels are Rising Faster and Faster, Threatening Coastal Cities. CNN.com has the post: “For around 2,000 years, global sea levels varied little. That changed in the 20th century. They started rising and have not stopped since — and the pace is accelerating. Scientists are scrambling to understand what this means for the future just as President Trump strips back agencies tasked with monitoring the oceans. Since 1993, satellites have kept careful watch over the world’s oceans, allowing scientists a clear view of how they are behaving. What they have revealed is alarming. Sea level rise was unexpectedly high last year, according to a recent NASA analysis of satellite data...”
Photo credit: Paul Douglas
Sweating to Shivering: Study Finds Rapid Swings in Temperature Have Increased. My perception for many years as a meteorologist is that “weather-whiplash” is on the increase. Now there is new data that seems to support that, as reported at The New York Times (paywall). Here’s an excerpt: “…The researchers examined temperature data from 1961 to 2023 to identify global patterns in sudden weather shifts, where temperatures in an area either jumped from cold temperatures to warm or plunged from warm to cold within five days. They found that instances of these flips increased in more than 60 percent of regions they surveyed. The largest increases in frequency were observed in South America, West Europe, Africa, and South and Southeast Asia. Some areas, including the polar regions, showed different behavior and experienced fewer events...”
Image credit: NOAA
How Trump Administration Job Cuts Could Affect the Future of Weather Forecasting. WBUR.com has the analysis; here’s a clip: “…Those are just two of the many National Weather Service employees who were notified about job cuts, and they both say the weather service is already understaffed. A report by the Associated Press found that half of the 122 National Weather Service forecast offices around the country have a 20% or greater staffing shortage. Experts say that is critical under staffing, and it will affect how these offices perform basic forecasts and warnings. We reached out to the National Weather Service and a spokesperson for its parent company. The National Oceanic and Atmospheric Administration sent an email statement saying, quote, we don’t discuss internal personnel and management matters…”
Kentucky NWS Forecast Office Faced Staffing Shortage Before Kentucky Tornadoes. USA Today reports; here’s the intro: “As destructive and deadly tornadoes bared down on Kentucky, National Weather Service officials triaged to provide life-saving forecasts and warnings amid federal staffing cuts. At least 23 people in the state died from powerful tornadoes that ripped through overnight May 16, and Gov. Andy Beshear said the death toll was expected to rise. Most of the deaths were concentrated in the eastern part of the state, which is served by the weather service’s Jackson, Kentucky, forecast office. The office is one of four forecast offices that no longer has overnight staffing because of a shortage of meteorologists, according to Tom Fahy, legislative director for the weather service employees union. Hundreds have left the agency amid cuts ordered by the Trump administration’s Department of Government Efficiency, led by Elon Musk, to slash the cost and size of the federal government...”
Credit: A weather balloon launch in Antarctica. (Image from NOAA.)
How Do You Report on the Weather When Data is Disappearing? NiemanLab has more details on the chaos engulfing America’s National Weather Service: “Since January, the National Oceanic and Atmospheric Administration (NOAA) and its subsidiary, the National Weather Service (NWS), have lost thousands of workers, either through layoffs or resignations as part of the Trump administration’s efforts to gut the federal government’s workforce. Overall, NOAA has lost more than 2,000 workers, or about 20% of its workforce, in the last four months. According to a recent report in CNN, 30 of the 122 weather forecasting offices around the country — including the ones that cover major cities like New York, Houston, and Cleveland — currently lack chief meteorologists; a number of NWS offices around the country no longer provide 24/7 forecasting...”
Trump Cuts Leave National Weather Service Scrambing to Cover Vital Shifts. More perspective on the NWS job cuts from USA Today: “…More than 550 of the 4,800 weather service employees were either dismissed, retired or accepted incentive offers to leave after the administration of President Donald Trump ordered agencies to reduce staff and draft reorganization plans. Now many of the nation’s 122 local weather service forecast offices, typically staffed 24/7, seven days a week, are short-handed. The departures included many senior level meteorologists who retired. In the Eastern Region alone, weather service employees tallied 700 years of experience lost...”
So Called “100 Year Floods” are Happening More Often. Yale Climate Connections has the post and interview; here’s an excerpt: “…A ‘100-year flood’ refers to a flood with a 1% chance of occurring each year – meaning, on average, a flood that bad will happen once in 100 years. The same goes for 500-year or 1,000-year floods. These likelihoods are calculated using historical records. But as climate change brings extreme weather and raises sea levels in many areas, the likelihood of a serious flood could be higher than these terms imply. Moftakhari: “The 100-year events that have been calculated based on historic records, let’s say back in 1950s or ‘60s, are no longer 100-year events…”
NOAA Predicts “Above Average” Hurricane Season. No El Nino wind shear to protect the coasts this summer and autumn, according to NOAA. The New York Times (paywall) explains: “The National Oceanic and Atmospheric Administration issued its forecast for this year’s Atlantic hurricane season on Thursday, saying it expected to see between 13 to 19 named storms this year. That would make for an above-average season, and most likely not as active as 2024 ended up being. An average Atlantic hurricane season has 14 named storms, including seven hurricanes and three major hurricanes. Ken Graham, the director of NOAA’s National Weather Service, said at a news conference on Thursday morning that the agency’s forecasters believed six to 10 of the named storms could become hurricanes, meaning they would include winds of at least 74 miles per hour. Those could include three to five major hurricanes — Category 3 or higher — with winds of at least 111 m.p.h...”
A summary infographic showing hurricane season probability and numbers of named storms predicted, according to NOAA’s 2024 Atlantic Hurricane Season Outlook. The official start of the Atlantic hurricane season is June 1 and runs through November 30. (See also news release text for data found within above graphic.) (Image credit: NOAA NWS)
NOAA’s Take on Hurricane Season 2025. NOAA has more details on why this may be a busier-than-normal hurricane season: “…The season is expected to be above normal – due to a confluence of factors, including continued ENSO-neutral conditions, warmer than average ocean temperatures, forecasts for weak wind shear, and the potential for higher activity from the West African Monsoon, a primary starting point for Atlantic hurricanes. All of these elements tend to favor tropical storm formation. The high activity era continues in the Atlantic Basin, featuring high-heat content in the ocean and reduced trade winds. The higher-heat content provides more energy to fuel storm development, while weaker winds allow the storms to develop without disruption. This hurricane season also features the potential for a northward shift of the West African monsoon, producing tropical waves that seed some of the strongest and most long-lived Atlantic storms...”
US Stops Tracking Costs of Extreme Weather Disasters Fueled by Climate Change. Here’s an explainer from PBS News Hour: “The National Oceanic and Atmospheric Administration will no longer track the cost of climate change-fueled weather disasters, including floods, heat waves, wildfires and more. It is the latest example of changes to the agency and the Trump administration limiting federal government resources on climate change. NOAA falls under the U.S. Department of Commerce and is tasked with daily weather forecasts, severe storm warnings and climate monitoring. It is also parent to the National Weather Service. The agency said its National Centers for Environmental Information would no longer update its Billion-Dollar Weather and Climate Disasters database beyond 2024, and that its information — going as far back as 1980 — would be archived…”
More Tornadoes and Fewer Meteorologists Make for a Dangerous Mix That’s Worrying US Officials. Local NWS staffs are being stretched, and severe weather warnings may be at increasing risk of not going out in time, reports Star Tribune: “…As of March, some of the weather service offices issuing tornado warnings Friday and Sunday were above the 20% vacancy levels that outside experts have said is a critical threshold. Those include Jackson, with a 25% vacancy rate, Louisville, Kentucky, with a 29% vacancy rate, and Wichita, Kansas, with a 32% vacancy rate, according to data compiled by weather service employees and obtained by the AP. Technologies used to predict tornadoes have significantly improved, but radar can’t replace a well-rested staff that has to figure out how nasty or long-lasting storms will be and how to get information to the public, said Karen Kosiba, managing director of the Flexible Array of Mesonets and Radars (FARM) facility, a network of weather equipment used for research…”
Map credit: Climate Central
More Frequent Fire Weather. Climate Central explains how a warmer, drier atmosphere, especially over the western US, is creating an environment with more frequent and potentially deadly wildfires: “…This analysis uses data from 476 weather stations to assess fire weather trends in 245 climate divisions spanning the contiguous U.S. from 1973 to 2024. On average, climate divisions in the western U.S. experience 31 fire weather days annually. That’s almost four times more than in the eastern U.S. (8 days annually). Wildfire seasons are lengthening and intensifying, particularly in the western U.S. Parts of the eastern U.S. have seen smaller but impactful increases in fire weather days...”