A look at weather extremes and the big-picture climate connections.

Twisters Past and Present: Interactive Tornado Tracker

By Climate Central

Tornadoes can happen anytime, anywhere in the world where conditions are right.

It just so happens that the U.S. is effectively the tornado capital of the world, with an average 1,200 tornadoes forming within its borders each year, according to the National Severe Storms Laboratory. Tornadoes have been observed on New Year’s Day, New Year’s Eve and every day in between, from California to Maryland, North Dakota to Texas.

With Climate Central’s Tornado Tracker, you can track tornado reports so far in the current year and investigate reports during past years. The tracker plots tornado reports from NOAA's Storm Prediction Center in Norman, Okla., and is updated multiple times a day to capture breaking events. (Keep in mind that tornadoes on the Tracker are just “reported” events, and have not yet been confirmed and that multiple reports can be sent in for the same tornado.)

Tornadoes happen when clashing air masses create an unstable environment, with some moisture thrown in there for good measure (though this doesn’t always result in a tornado -- scientists don’t fully understand why). Generally, the prime time and location for this set of ingredients to come together is during spring and early summer, smack dab in the middle of the country -- the proverbial Tornado Alley (though this is not a scientifically defined term). This is especially true for so-called supercell tornadoes, generally the strongest and most destructive, which are spawned...

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Science Made Simple: Take the Dog for a Walk

Oftentimes scientists and journalists make the simplest of scientific concepts sound incredibly complicated. Take the difference between climate and weather, for example. The old adage is that "climate is what you expect, weather is what you get," since day-to-day weather may depart significantly from average conditions. But that doesn't really tell you much about how climate is measured over the long-term, or when weather ends and climate begins. The explanation I like best comes from the comedian Stephen Colbert, when, during a segment with Climate Central's Heidi Cullen, he said: "Is not climate just made up of thousands of little weathers?"

Or consider this delightfully clear cartoon posted on Youtube that uses a unique analogy — a man walking his dog — to describe the differences between weather and climate. It's simple, to the point, and best of all, adorable. Check it out. 

Monster Cyclone Phailin Poses Deadly Threat to India

One of the strongest tropical cyclones to form in the Bay of Bengal since 1980 is heading for the northeast Indian state of Odisha, packing winds of close to 160 mph and a storm surge of at least 10 feet, but possibly much higher. The storm, named Phailin — a Thai word for “sapphire” — has intensified after weakening for a time on Thursday. By some measures, it may already have become the strongest storm on record in the Indian Ocean. It is expected to make landfall in Odisha or the far northeastern corner of the Andrha Pradesh State on Saturday afternoon or early evening.

Enhanced satellite view of Tropical Cyclone Phailin as it approached the Indian coast on Oct. 11.
Credit: NOAA

The history of the Bay of Bengal region is littered with examples of tragic storms, and this one has the potential to kill thousands and displace many more. The storm is expected to be the equivalent of a Category 4 or 5 hurricane at landfall, bringing a life-threatening storm surge, heavy rains, and high winds to a broad swath of northeastern India. (Although named differently, tropical cyclones have the same characteristics as hurricanes and typhoons.)

The Bay of Bengal, which borders India, Pakistan, Bangladesh, Myanmar, and Sri Lanka, has been home to the deadliest tropical cyclone disasters on Earth. A whopping 26 of the 35 deadliest tropical storms worldwide formed in the Bay of Bengal, the Capital Weather Gang blog reported. That includes Cyclone Nargis, which struck Myanmar...

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The Most Detailed Visuals of Hurricane Sandy, Revealed

Scientists have recently developed awe-inspiring visualizations of Hurricane Sandy, which devastated the Northeast and Mid-Atlantic states a year ago. The visualizations, created using state-of-the-art computer models, provide some of most detailed looks at any hurricane to date.

In this 3-D map of potential temperature, relatively cool air wraps around Sandy's core near the surface (purple and blue colors), while air parcels gain heat from moisture condensing into clouds and precipitation as they ascend through the storm’s core.
Click image to enlarge. Credit: UCAR.

Scientists based at the National Center for Atmospheric Research (NCAR) in Boulder, Colo., used an advanced hurricane computer model to create mesmerizing images and animations that almost succeed in making the destructive and deadly storm appear to be a beautiful work of art.

The hurricane went through multiple phases. After rumbling through the Caribbean and striking Cuba, it veered north-northeastward just off the East Coast. The storm was officially classified as a post-tropical cyclone as of 7 p.m. EDT on Oct.29, 2012, only an hour before it made landfall, and after hurricane force winds had already begun buffeting the New York and New Jersey coastlines.

Climate Central posted the initial round of visualizations from this team in January. But now, a team including NCAR's Mel Shapiro, the National Center for Computing Applications (NCSA), Cray Computing, and the U.S. Office of Naval Research has produced addition simulations at even higher resolution. 

The visualizations show how Sandy’s life cycle was unique — going through multiple tropical and non-tropical phases as it interacted with the jet stream and surface weather features, such as a cold front draped along th...

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‘Atmospheric River’ Smashes Records in Pacific Northwest

A barrage of unusually intense early-autumn storm systems swept across the Pacific Northwest this weekend, bringing hurricane-force winds and dumping enough rain to smash all-time monthly rainfall records from Seattle to Portland.

In Seattle and Olympia, Wash., Sept. 28 was the wettest September day on record. In Seattle, 1.71 inches of rain fell, which was more rain than typically falls during the entire month.

Water vapor satellite image showing the "atmospheric river" extending from near Hawaii in the lower left to the Pacific Northwest in the upper right. Arrows indicate the direction of moisture transport.
Credit: U. Wisc. via Facebook/Stu Ostro.

The rainfall was the product of a long, snake-like plume of moisture that stretched from near Hawaii to the gulf of Alaska, and it aimed squarely at the Pacific Northwest. These moisture plumes are sometimes called “atmospheric rivers,” which are responsible for some of the most damaging flooding events along the U.S. West Coast, particularly in California.

Some of the moisture originally came from Typhoon Pabok, which was in the western Pacific several days ago, according to the National Weather Service.

The highest rainfall totals were recorded in mountainous areas, with 5-10 inches or more of rainfall commonplace in the higher elevations of Oregon and Washington. Lees Camp, Ore., for example, recorded 11.10 inches of rain from Sept. 27-30, and Tillamook, along the north Oregon coast, received 6.84 inches.

A weather station on Mount St. Helens recorded 15.30 inches of rain during the same period.

The Portland metro area saw between 3-4 inches of rainfall, which is extremely rare for this time of year. Oregon wine country was also aff...

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