Tag: extreme-weather

New study finds a potential predictor for long-range US tornado forecasts

Tornadoes are among the deadliest and costliest natural disasters in the United States and are one of the hardest to predict. In December 2021, the most destructive winter tornado outbreak, known as the Quad-State Tornado Outbreak, caused 89 fatalities, 672 injuries, and at least $3.9 billion in property damages. Scientists at the University of Miami’s Cooperative Institute of Marine and Atmospheric Studies (CIMAS) and NOAA’s Atlantic Oceanographic and Meteorological Laboratory (AOML) investigated this outbreak and found that it occurred under an exceptionally strong and prolonged negative Pacific-North American (PNA) pattern, which created favorable conditions for tornado outbreaks.

Read Full Article
A bright yellow sun sits above trees in a orange sky.

Larger than Normal Atlantic Warm Pool Leads to an Increase in US Heat Waves

Heat extremes are the number one weather-related cause of death in the United States, prompting the climate community to study the driving forces behind these extreme events to improve their prediction. A new study published in the Journal of Geophysical Research finds an increase in summertime heat wave occurrence over the US Great Plains is linked to a larger than normal tropical Atlantic warm pool. 

Read Full Article

An Experimental Outlook Model Shows a Useful Skill for Predicting Seasonal US Tornado Activity

A new paper published in Monthly Weather Review shows some promise for predicting subseasonal to seasonal tornado activity based on how key atmospheric parameters over the US respond to various climate signals, including El Niño and La Niña activity in the Pacific. In this study, a team of researchers from NOAA’s Atlantic Oceanographic and Meteorological Laboratory, Geophysical Fluid Dynamics Laboratory, and Climate Prediction Center presented an experimental seasonal tornado outlook model, named SPOTter (Seasonal Probabilistic Outlook for Tornadoes), and evaluated its prediction skill.

Read Full Article
El Nino Satellite Image. Image Credit: NOAA National Environmental Satellite, Data, and Information Service (NESDIS)

The Atlantic Niño: El Niño’s Little Brother

Despite their differences, it is still widely thought that Atlantic Niño is analogous to El Niño in many ways. Specifically, the atmosphere-ocean feedback responsible for the onset of Atlantic Niño is believed to be similar to that of El Niño, a process known as Bjerknes feedback. The near-surface trade winds blow steadily from east to west along the equator. When weaker-than-normal trade winds develop in the western Atlantic basin, downwelling equatorial Kelvin waves propagate to the eastern basin, deepening the thermocline and making it harder for the colder, deeper water to affect the surface.

Read Full Article

AOML Scientists Tackle one of the Most Challenging Problems in U.S. Seasonal Rainfall Prediction

In a recent article published in Geophysical Research Letters, AOML and CIMAS scientists investigated U.S. rainfall variability, focusing on the late summer to mid-fall (August-October) season. The main goal of the study was to identify potential predictors of U.S. precipitation during August-October and to explore the underlying physical mechanisms.

Read Full Article

Connection between Madden-Julian Oscillation and U.S Tornadoes may Provide Earlier Warning for Storms

Recently, scientists at NOAA’s Atlantic Oceanographic and Meteorological Laboratory (AOML) and the Cooperative Institute for Marine and Atmospheric Studies (CIMAS) explored the physical causes between U.S. tornado activity and the Madden-Julian Oscillation. In a study recently published in the Journal of Climate (Kim et al., 2020), they showed that a series of key atmosphere-ocean processes are involved in the remote impact of Madden-Julian Oscillation on U.S. tornado activity.

Read Full Article