After two wild days of tornado devastation across the U.S. on Sunday and Monday, an unexpected break occurred on Tuesday, when only nine tornadoes touched down. NOAA’s Storm Prediction Center (SPC) had issued a forecast for a “Moderate Risk” of severe weather over much of Alabama and Mississippi, but none of Tuesday’s tornadoes hit those states. Instead, North Carolina saw the bulk of the activity, with eight preliminary reports of tornadoes.
JeffMasters, • 2:31 PM GMT on April 30, 2014
A swarm of deadly and devastating tornadoes ripped through the Southeast U.S. on Monday, killing at least 13 people, bringing the two-day death toll from this week’s tornado outbreak to at least 29. Hardest hit were Mississippi and Alabama, which lay in the bullseye of the High Risk” area for severe weather issued by NOAA’s Storm Prediction Center early that afternoon. It was the second consecutive day a “High Risk” outlook had been issued by SPC, and the threat of strong and deadly tornadoes continues again on Tuesday, with a “Moderate Risk” of severe weather expected over Alabama and Mississippi.
JeffMasters, • 2:13 PM GMT on April 29, 2014
The quiet 2014 severe weather season turned grimly violent over the weekend, as multiple deadly tornadoes ended our record-long start to a year without a tornado fatality. Media reports put Sunday's death toll at 18, with 16 of deaths in Arkansas, one in Iowa, and one in Oklahoma. Hardest-hit were Mayflower and Vilonia, Arkansas, located about fifteen miles north of Little Rock. A large and powerful tornado that had been on the ground nearly an hour carved through the region near sunset, killing at least ten people.
JeffMasters, • 1:07 PM GMT on April 28, 2014
The majority of tornado deaths occur in mobile homes, but tornado experts have long wondered why mobile home parks seem to get disproportionately more tornado strikes than other residential areas. New research by Purdue University researchers suggests that "transitions zones"--areas where dramatically different landscapes meet, like where a city fades into farmland, or a forest meets a plain--are more prone to tornado touch downs. Since mobile home parks are often located at the edge of built-up areas, they may actually get hit more often.
JeffMasters, • 3:47 PM GMT on April 25, 2014
March 2014 was the globe's 4th warmest March since records began in 1880. March 2014 global land temperatures were the 5th warmest on record, and global ocean temperatures were also the 5th warmest. The year-to-date January - March period has been the 7th warmest on record for the globe. One billion-dollar weather-related disaster hit the Earth during March 2014: Southeastern Brazil's worst drought in 50 years, which has cost at least $4.3 billion so far this year.
JeffMasters, • 1:21 PM GMT on April 23, 2014
Today is Earth Day, a day to celebrate the beauty of the atmosphere, oceans, and biosphere of the planet that sustains us. As is my tradition on Earth Day, I present my favorite wunderphotos uploaded to our web site over the past year. I want to thank everyone who has participated in making this the largest (1.7 million!) and best weather photo gallery on the Internet--your photos are truly an inspiration!
JeffMasters, • 11:50 AM GMT on April 22, 2014
I'll share with you today a few of the more interesting inquiries I've gotten during my 20 years working with Weather Underground. I responded to all of the emails, but not the phone calls. The first: It turns out that there is a person in Texas who uses our Nexrad radar imagery to locate people. He can pick up their frequencies from the Nexrad imagery. It turns out that human frequencies are embedded in each image. He would not explain to me how he picks up these frequencies, since it is a proprietary process, invented by him.
JeffMasters, • 3:34 PM GMT on April 21, 2014
JeffMasters, • 9:18 PM GMT on April 18, 2014
From November 2013 - January 2014, a remarkably extreme jet stream pattern set up over North America, bringing the infamous "Polar Vortex" of cold air to the Midwest and Eastern U.S., and a "Ridiculously Resilient Ridge" of high pressure over California, which brought the worst winter drought conditions ever recorded to that state. A new study by Utah State scientist S.-Y. Simon Wang found that this jet stream pattern was the most extreme on record, and likely could not have grown so extreme without the influence of human-caused global warming.
JeffMasters, • 6:56 PM GMT on April 16, 2014
We are transitioning to a completely new logo, as part of a site-wide redesign aimed at furthering our mission of unlocking and sharing vast amounts of weather data with as many people as possible using the latest digital technologies, in a way that is visually appealing and engaging. We kept the colors and vibrancy of the rainbow but replaced the rainbow shape with the letters "WU"; a raindrop over the "U" represents rain falling into a rain gauge, a nod to our incredible Personal Weather Station (PWS) community (34,000 strong!)
JeffMasters, • 12:13 PM GMT on April 15, 2014
Climate change is a huge threat to civilization if we do nothing more to reduce it, but the costs are very affordable if we start now, said the Nobel-prize winning Intergovernmental Panel on Climate Change (IPCC) today, in the third installment of their once-every-seven-years report on the climate. Today's report on mitigation--how we can slow down climate change--found that the cost of keeping global warming under the "dangerous" level of 2°C will only reduce "consumption growth" of the global economy by 0.06% per year if we start immediately and act strongly. Consumption growth is expected to increase between 1.6% and 3% per year in the coming decades.
JeffMasters, • 7:10 PM GMT on April 13, 2014
Category 4 Tropical Cyclone Ita powered ashore along Australia’s Queensland coast near 9 pm local time (10 UTC) on Friday with sustained winds rated at 145 mph by the Joint Typhoon Warning Center. Fortunately, Ita appeared to be undergoing an eyewall replacement cycle at landfall, and was probably weaker than a Category 4 storm when it came ashore. Ita hit a portion of the coast that is relatively lightly populated, and damage should be nowhere near the $3.6 billion price tag of Tropical Cyclone Yasi of February 2, 2011.
JeffMasters, • 3:36 PM GMT on April 11, 2014
Dangerous Category 4 Tropical Cyclone Ita is nearing landfall in Australia’s Queensland state. Maximum sustained winds were 155 mph at 18 UTC on Thursday, just 1 mph below the threshold of Category 5 strength, and Ita had a central pressure of 930 mb. Satellite loops show a moderate-sized tropical cyclone surrounded by an intense eyewall with very cold cloud tops. Radar loops from Cairns, Australia show spiral bands from Ita are already bringing heavy rains to the coast.
JeffMasters, • 10:32 PM GMT on April 10, 2014
Effective story telling is essential to communicating important truths, since it acts on a gut level. That's why I'm excited about the latest effort to tell the story of climate change by one of Hollywood's master story tellers--James Cameron, creator of Titanic and Avatar. Dangerous climate change is already upon us, and I look forward to seeing this greatest story of our time being told on Showtime's “Years of Living Dangerously” on Sunday evenings over the coming weeks.
JeffMasters, • 12:55 AM GMT on April 09, 2014
Fresh water can be wrung out of the ocean by forcing it through filtration membranes used in the reverse osmosis process. The high pressures needed consumes more energy than it takes to pump water from Northern California rivers to Los Angeles over a 2000'-high mountain obstacle. Desalinized water provides less than 1% of California's fresh water, and costs nearly double what water imported from Northern California rivers and the Colorado River costs. Given that desalinized water is "drought-proof", there are efforts to greatly expand the creation of fresh water from the sea.
JeffMasters, • 2:53 AM GMT on April 07, 2014
There have been tremendous changes in the Pacific Ocean over the past two months which continue to favor a moderate to strong El Niño event later this spring and summer. We are currently observing what looks to be the strongest downwelling oceanic Kelvin wave event since satellite records began in the 1970s.
Michael Ventrice • 3:19 PM GMT on April 04, 2014
On the night of August 17, 1969, mighty Category 5 Hurricane Camille smashed into the Mississippi coast with incredible fury. Up until now, Camille's landfall intensity had been rated at 190 mph--the highest on record for an Atlantic hurricane. However, Camille's landfall intensity has now been officially downgraded to 175 mph, thanks to a reanalysis effort. The top spot is now held by the Great 1935 Labor Day Hurricane (185 mph winds and a central pressure of 892 mb at landfall.)
JeffMasters, • 2:48 PM GMT on April 02, 2014