Tuesday, April 29, 2014

Severe Risk Shifts to East Coast (are tornadoes becoming more intense?)


Low Expectations

"Keep your expectations low. That way you may be pleasantly surprised from time to time."
Good advice, especially for a meteorologist. Especially this "spring". Goldilocks had a point: rarely is our weather "just right". It's usually too hot-cold-wet-dry. The 7-Day Outlook should come with a 7-Day supply of Zoloft.

But here's what I've discovered: the weather has an uncanny way of evening things out. It may not happen next week or next month, but this cold, foul, puddle-infested FAIL of a spring will be balanced by an extended spell of gloriously lukewarm blue-sky postcard-worthy days.

Then again I have been standing way too close to the Doppler.

Any unwanted slush in your yard gives way to rain showers today as temperatures aloft begin to mellow. Puddles shrink tomorrow as skies brighten; 50s will feel like sweet relief this weekend as the sun makes a rare cameo appearance. Next week will feel like spring again; consistent 60s and even a few low 70s by the second week of May.

Like a cruel meteorological mirage spring keeps getting pushed back.

And as much as I'm rooting for warm fronts to reach our lofty latitude, my hope is that we have a quiet tornado year in Minnesota. Stay tuned.

* photograph of a new lake in a farmer's field near Cologne, Minnesota courtesy of WeatherNation meteorologist Bryan Karrick.

** Second wettest April on record in the Twin Cities. The Star Tribune has details. More data from NOAA here.

Unstuck. The stormy pinwheel of moisture that has stalled out over the Ohio Valley much of this week, sparking tornado outbreaks in the south and soaking rains from the Ohio Valley and Great Lakes into the Upper MIdwest, will finally get kicked out to sea by late week. Another clipper-like system may push a few scattered instability showers into Minnesota on Friday. NAM Future Radar: NOAA and HAMweather.

East Coast Soaking. Some 2-3"+ rainfall amounts are likely from Washington D.C. to Albany today and early Thursday, capable of minor flooding problems over the Mid Atlantic and New England. Data: 84 hour NAM model, courtesy of NOAA and HAMweather.

Severe Threat Lingers - Not As Extreme. I'm happy to see a lack of "Moderate Risk" from NOAA SPC, a slight risk from Washington D.C. to Charlotte, Atlanta and Orlando later today with hail, straight-line winds and a few isolated tornadoes possible.

Another Springy Mirage? Probably not. The ECMWF model is fairly consistent pulling 60-degree air back into Minnesota next week. You may even be able to lose the jacket for a couple of days. Today will be raw, but spring returns in all it's glory by Tuesday. Graphic: Weatherspark.

Cheering On The 45-Day Wish-Cast. Confidence levels remain low on details, but the sun is climbing higher in the sky; at some point it WILL warm up. NOAA's 45-day CFS (Climate Forecast System) trend shows fairly consistent 60s in May, with 80s surging into Minnesota in June. Better late than never. Source: HAMweather.

72 Hour Rainfall Amounts. Most parts of the Twin Cities metro just picked up an April's worth of rain since Saturday. Check out some of the amounts, courtesy of the Twin Cities National Weather Service:
LocationCounty, ST

Provider72 Hr Pcpn
N SAINT PAUL 1 NW RamseyECMNCOCORAHS4.97
FALCON HEIGHTS 2 SSE RamseyECMNCOCORAHS4.11
VICTORIA 2 ENE HennepinECMNCOCORAHS4.07
COLUMBIA HEIGHTS 1 S HennepinECMNCoCoRaHS3.87
CHANHASSEN NWSCarverECMNCOOP3.72
BUFFALOWrightCMNAWOS3.64
ANOKA 2 SE AnokaECMNCOCORAHS3.60
ST CLOUD AP SherburneCMNASOS3.58
CHANHASSEN 1 SE CarverECMNCOCORAHS3.51
FOREST LAKE 5NEChisagoECMNCOOP3.49
ST CLOUD SCSUStearnsCMNUCOOP3.48
JORDAN 1SWScottECMNCOOP3.47
CRYSTAL AP HennepinECMNASOS3.44
DELANOWrightCMNCOOP3.38
KIMBALL 3NStearnsCMNCOOP3.34
MPLS LWR ST ANTHONY FALLSHennepinECMNCOOP3.31
MANKATO 4EBlue EarthSCMNUCOOP3.20
ST PAUL DWNTN APRamseyECMNASOS3.14

Mississippi Weatherman Evacuates On Air As More Tornadoes Hit The South. Everyone wants to err on the side of caution, even the local meteorologist in the path of a large, violent tornado. At least this station in Tupelo has a basement, which came in handy Monday afternoon. New York Magazine reports (check out the video clip): "...A video from NBC affiliate WTVA offers a dramatic illustration of that point. On Monday afternoon chief meteorologist Matt Laubhan was reporting on the storm live on air when a tornado touched down near the station in Tupelo, Miss. After the feed stalls for a moment, Laubhan yells "Basement, now!" to other employees, then runs off camera. Later, the station tweeted "We are safe here..."

Four Things That Turn America Into The "Tornado Super Bowl". Where have you heard that before? NBC News has an explainer, focused on why the USA experiences (far) more tornadoes than any other nation on Earth; here's a clip: "A one-of-a-kind combination of weather factors make the United States the twister capital of the world, with the ominous funnels 10 times more common in the states than anywhere else on the planet, scientists say. The four main ingredients all are geographical, all unique to America's borders: a massive mountain wall to the west, a warm ocean to the southeast, a cold-air “shield” to the north – and above these particular latitudes, a narrow river of wind, the jet stream, that surges eastward at hundreds of miles per hour..."

Little Rock Outbreak Details. Here is additional information on the Sunday evening outbreak that leveled parts of Vilonia and Mayflower, courtesy of the Little Rock, Arkansas National Weather Service: "In the picture: Rotation associated with the parent storm on 04/27/2014 was persistent for roughly 40 miles (Tornado #1) before weakening (where the gap is indicated). Another tornado (Tornado #2) was likely spawned a short time later by the same storm and tracked through White, Jackson, and Independence Counties. Note: Tornado #2 may actually be several tornadoes. This will be determined through damage surveys. The graphic is courtesy of the National Severe Storms Laboratory..."

• This is the strongest tornado to hit the state since the Denning tornado on May 24-25, 2011. That tornado was rated EF4, with a path length of 45.71 miles. Four were killed, 27 injured. The fatalities were at Etna and Denning in Franklin County, and Bethlehem in Johnson County, all in mobile homes.

• This is the second time in three years that Vilonia has been hit by a tornado. The last time was April 25, 2011, when a long-tracked EF2 tornado hit, killing four.

• Since reliable records began in 1950, Vilonia has seen five tornado tracks within the present-day city limits. Aside from 4/27/2014, there was 4/25/2011 (EF2), 12/24/1982 (F3), 12/23/1982 (F2), and 03/12/1961 (F2). Source: National Weather Service, Little Rock.

* 2 confirmed deaths from Sunday's tornado outbreak in Iowa. Details here.

Preliminary Tornado Ratings:
EF-4: Louisville, MS
EF-3: Mayflower/Vilonia AR, Limestone County, AL (at least), Tupelo, MS
EF-2 : Union City, TN, Heard/Troup County, GA
EF-1 : Kimberly, AL (north Jefferson County)

Storm Chaser Says He's Retiring After Deadly Arkansas Tornado. CNN has a remarkable interview with a storm chaser who's apparently had enough; here's the description: "Deadly tornadoes have left a path of death and destruction for miles in the south. Our Ed Lavandera is in Mayflower, Arkansas where he caught up with a storm chaser who came dangerously close to it all. He tells us why his experience on Sunday will be his last."

Tornado "Scar". Chris Dolce points out a comparison of high-resolution NASA MODIS images taken before and after the Mayflower-Vilonia tornado. You can see the damage swath left behind in the top image, taken April 28.

Most Tornado Watches? Looking at data from 1999-2008 the most tornado watches issued by NOAA SPC weren't in traditional Tornado Alley, but southern Alabama and Mississippi; an average of 16 tornado watches every year. Not quite what I was expecting.

Giving Credit Where Credit Is Due. Meteorologists take a lot of flak for missing forecasts, but the folks at NOAA SPC in Norman, Oklahoma nailed the tornado prediction Sunday, again on Monday. That's the topic of today's first Climate Matters segment: "WeatherNationTV Chief Meteorologist Paul Douglas goes over the factors that went into the historic tornado outbreak that dropped large destructive tornadoes over Alabama and Mississippi. What has to happen to make a situation like this occur?"

Dome It! Schools Can Affordably Survive Tornadoes. Yes, tornadoes are a threat, and an opportunity to make our communities more resilient and storm-prooof. Here's an excerpt of a timely, interesting article from Andrew Revkin at The New York Times: "... I spoke Monday with David B. South, the co-inventor of a dome manufacturing process 37 years ago whose company, Monolithic Dome, has been erecting storm-safe domed school buildings from Sarasota, Fla., through Geronimo, Okla., and Lumberton, Tex., and even west to Payson, Ariz. (where the benefits include the big energy savings that come with thick insulation and concrete). There are ways to build a safe haven into a conventional school design, as well. But old building codes, tight budgets and simple inertia continue to get in the way of change..."

Photo credit above: Monolithic Dome. "A domed building at the Dale, Okla., elementary school doubles as a tornado shelter and cafeteria."

Supercell. Check out the timelapse footage of a supercell thunderstorm passing over Des Moines, courtesy of meteorologist Jason Parkin. Great animation.

Why It's Hard To Outsmart A Tornado (And How Scientists Are Trying). NBC News has an interesting story about the difficulty in determining which supercell thunderstorms will go on to spawn large/deadly tornadoes. As a nation we over-warn for twisters, which is probably better than the alternative. Here's an excerpt: "...As a result, Wurman said forecasters tend to "overwarn" about tornadoes. The false-alarm rate for tornado warnings is about 75 percent. But Brooks said it's better to sound a false alarm than to risk missing a killer tornado. "That 75 percent number is a result of the fact that deciding whether this is a tornado-making storm is a fundamentally hard problem," he said..." (Image: Gene Blevins, Reuters).

Tornado Tip-Offs. Meet the new starting pitcher for the Twins. There's a sign of The Apocalypse. No, I'm using visual aids to remind you about hail and tornadoes. Most large, violent tornadoes are preceded or accompanied by large hail. The larger the hail, the stronger the thunderstorm updraft. The stronger the updraft the higher the probability of a supercell powerful enough to tornado. That's the subject of this Climate Matters segment: "Large destructive storms capable of dropping baseball sized hail and damaging tornadoes don't happen where you think. WeatherNationTV Chief Meteorologist Paul Douglas shows just where most of these powerful storms are witnessed."

Tornadoes: The Science Behind The Destruction. National Geographic has more good information and background on tornadogenesis - here's a clip: "...Even then, "we still don't know why some thunderstorms create tornadoes while others don't," tornado-chaser Tim Samaras said in early 2013. Samaras was a scientist and National Geographic grantee who was killed by a twister on May 31, 2013, in El Reno, Oklahoma. (Read "The Last Chase" in National Geographic magazine.) Brooks says scientists believe strong changes in winds in the first kilometer of the atmosphere and high relative humidity are important for the formation of tornadoes. He adds that there also needs to be a downdraft in just the right part of the storm..."

From "Gale" To "Inconceivable". Ranking Tornado Strength. Here's a good explanation of the new enhanced Fujita (EF) scale, courtesy of an article at Time Magazine: "...The Enhanced Fujita scale was adopted in 2007. It was designed to more accurately reflect the actual damage a tornado had done on the ground. The EF scale uses 28 different damage indicators, ranging from small barns to hardwood trees to shopping malls—and each of those indicators is assessed based on several different points of possible damage..."

61 Facts About Tornadoes. Here are just a few from abc15.com in Phoenix:
- "A tornado emergency is enhanced wording in a tornado warning indicating a large tornado is moving into a heavily populated area. Significant widespread damage and numerous fatalities are likely. The term was coined by forecasters in May 1999 and is used sparingly.
- Enhanced Fujita Scale: The Fujita scale is used to estimate the wind speed of a tornado by the damage the tornado causes."

* details on the 1965 Palm Sunday tornado outbreak, featured above, from Wikipedia.

Yes, Tornadoes Are Getting Stronger. To be fair and balanced, there is still no widely accepted scientific gun that can directly connect the dots, to the point we can say "climate change absolutely produces more numerous or more powerful tornadoes". But this story out of Wired just made me do a double-take; here's a clip: "...A tornado-power equation that actually gauges a twister’s kinetic energy would be more useful to scientists who are also examining the effects of climate change, so that’s what Elsner built. He looked at the length and width of a storm’s damage path, correlated that to the amount of damage, and then used the result to estimate wind 1.0 speed. A little more crunching and bam!—integrated kinetic energy of a storm. Non-linear upward trend estimated values of kinetic energy Elsner’s analysis suggests that since the turn of the century, tornadoes have packed a more powerful punch..."

Researchers Develop Model To Correct Tornado Records. With Doppler (and a proliferation of storm chasers after the movie "Twister" was released in the early 90s) we've seen an apparent uptick in tornadoes. More people and technology looking for them. But are tornadoes becoming more intense over time? Here's a clip from a story posted by Florida State University: "...The increase in reports has diminished the population bias somewhat, but it introduced a second problem: There are more reports, but are there also, in fact, more tornadoes? In other words, is the risk actually increasing? To address these issues, the FSU researchers first made the assumption that the frequency of tornadoes is the same in cities as in rural areas. They also operated on the assumption that the reported number of tornadoes in rural areas is low relative to the actual number of tornadoes. Their model calls for the reported number in rural areas to be adjusted upward by a factor that depends on the number of tornadoes in the nearest city and the distance from the nearest city. The model shows that it is likely that tornadoes are not occurring with greater frequency, but there is some evidence to suggest that tornadoes are, in fact, getting stronger..."

100-Degree Heat Brewing For Los Angeles Area - Records May Fall. 100F in late April? Here's an excerpt from The Los Angeles Times: "A heat wave this week is expected to send temperatures soaring to 20 degrees above normal for much of the Southland, potentially breaking records with triple digits in some areas, forecasters say. Building high pressure is also expected to bring gusty Santa Ana winds to the region, prompting warnings of high fire danger, particularly Tuesday through Thursday, when temperatures could hit 100 degrees in some inland areas, the National Weather Service said..."

* forecast graphic above: NOAA and HAMweather.


Phones Are Giving Away Your Location, Regardless Of Your Privacy Settings. No, you're not paranoid - you are being tracked until further notice. Maybe if I start using my old brick phone...? Quartz has the story; here's an excerpt: "...A new study has found evidence that accelerometers—which sense motion in your smartphone and are used for applications from pedometers to gaming—leave “unique, trackable fingerprints” that can be used to identify you and monitor your phone. Here’s how it works, according to University of Illinois electrical and computer engineering professor Romit Roy Choudhury and his team: Tiny imperfections during the manufacturing process make a unique fingerprint on your accelerometer data..."

Confirming Our Suspicions: Oreos Are As Addictive As Crack. Here's a clip from a story at Huffington Post: "...Thanks for telling us what we already knew, science! Just last year, a team at Connecticut College got a bunch of lab rats, Oreos, and cocaine, and set off for Vegas. Actually, they set up two mazes. The first maze had Oreos at one end and rice cakes on the other; the second promised an injection of saline on one side and an injection of morphine/cocaine at the other. After they had received their prize, the rats could choose to linger as long as they liked, presumably in the hopes of seconds they would never get..."

Best TV News Bloopers Of April. There are some really good ones in here - video courtesy of TVNewsCheck. (PG rated).


Climate Stories...

* cartoon courtesy of David Horsey at The Los Angeles Times.

Typhoon Haiyan Was Just The Start - Prepare For An Even Stormier Future. As oceans continue to warm will hurricanes and typhoons become more intense over time? Here's an excerpt from The Guardian: "...The damage Haiyan caused outstripped any storm the typhoon-prone islands had experienced before. Reibl says typhoon Bopha in 2012 had already redefined ideas on how big a typhoon could get, and yet "just a year later, Haiyan made Bopha seem like just a little wind … When Bopha happened we didn't envisage a Haiyan. Can we envisage something more than Haiyan?" Reibl says that in the past the Philippines were considered the 7-11 of natural disasters – small but open all hours. Indonesia, with its large but infrequent disasters, was more like a mega mall. He says the scale of devastation wrought by Haiyan meant the Philippines had become "a mega mall that is now also open 24/7"...

Photo credit above: "An aerial photograph of a coastal town in Samar province in central Philippines, taken on 11 November 2013." Photograph: Erik De Castro/REUTERS.

Top Military Commanders Have Declared Our Biggest Threat, And It's One We're All Ignoring. I have a son in the Navy and I can assure you that Navy brass take climate change very seriously. Seas are rising; that will impact Navy ports in the years and decades to come. Anything that potentially destabilizes economies and can spark conflict is of great interest to the Pentagon. Here's an excerpt from PolicyMic: "...For the U.S. military, climate change isn't just about sad-looking polar bears and declining biodiversity. It's a real challenge that has the potential to seriously destabilize nations and throw entire regions into conflict, potentially escalating into wars that will require new strategies and new technologies to win. In a recent interview with the Responding to Climate Change blog, retired Army Brig. Gen. Chris King said that the military is extremely concerned about climate change. "This is like getting embroiled in a war that lasts 100 years..."

Supreme Court Backs EPA Rules For Coal Pollution. The New York Times has an update - here's an excerpt: "The Supreme Court on Tuesday upheld the Environmental Protection Agency’s authority to regulate coal-plant pollution that wafts across state lines from 27 Midwestern and Appalachian states to eastern states. The 6-to-2 ruling is a major environmental victory for the Obama administration, which has instituted several new E.P.A. regulations under the Clean Air Act in an effort to crack down on coal pollution. Republicans and the coal industry have criticized the effort as a “war on coal...”

File photo: Matt Brown, AP.

Climate Scientist Katherine Hayhoe On Time Magazine's Most Influential People of 2014 List. Here's an excerpt of an interview with Dr. Hayhoe from The University of Toronto: "... I’m encouraged when international relief and development organizations like World Vision put climate change at the forefront of their concerns. I’m inspired by faith leaders from Pope Francis to the U.S. National Association of Evangelicals who emphasize how the Christian faith demands a response to climate change. With 97 per cent of climate scientists agreeing that climate change is happening due to the choices people make every day, the simple truth is that the scientific debate is over, and now it’s time for all of us, from every walk of life and part of society, to take action..."