Tornado's in de VS #25 A new day

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8+ Very high probability of a tornado
6 - High probability of a tornado
4 - Moderate chance of a tornado nearby, but hail and/or high wind gusts possible
2 - Low chance of a tornado, but hail and/or high wind gusts possible
0 - Near-zero chance of a tornado or a severe thunderstorm

BIRTH OF INCREDIBLE EF-4 TORNADO!

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Op woensdag 27 april 2016 01:53 schreef MaryMouse het volgende:
Kan je tegenwoordig niet meer 'bij' chasers in de 'auto' springen? Al mijn linkjes geven wel de locatie van de auto's aan, maar geen live stream meer.

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Op woensdag 27 april 2016 09:48 schreef INViCTuS het volgende:
Beter voor de mensen daar

Nieuwe kansen zullen ongetwijfeld snel volgen

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Op donderdag 28 april 2016 02:57 schreef RipCity het volgende:
Goed artikel over gisteren en berichtgeving eromtrent: https://www.washingtonpos(...)&utm_campaign=buffer

twitter:

AMHQ twitterde op donderdag 28-04-2016 om 12:27:10 17 reports of #tornadoes yesterday in six states. This EF-1 in #Omaha was among them. No #injuries were reported. https://t.co/ZGOcGaEeWa reageer retweet

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Op donderdag 28 april 2016 19:57 schreef Houtenbeen het volgende:

twitter:

TVNweather twitterde op donderdag 28-04-2016 om 19:45:32 After careful thought and consideration, we have decided to discontinue the TVNweather Live Storm chasing service: https://t.co/Pn5bIVjopI reageer retweet

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Op dinsdag 10 mei 2016 18:10 schreef aloa het volgende:

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Violent Katie-Wynnewood, OK Tornado 5/9/2016

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Op woensdag 11 mei 2016 11:08 schreef mouzzer het volgende:
Foto van het schadepad van de 'stovepipe' tornado:

[ afbeelding ]

Zo te zien bovenstaande foto de plek welke vanaf minuut 10 in onderstaande video te zien is waar de tornado de weg over lijkt te steken maar dan stuk terug gaat om z'n pad weer te vervolgen. Op de foto is te zien dat hij op dat moment precies tussen de 2 witte gebouwen door is gegaan.

Violent Tornado East of Katie, OK (5/9/2016)

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Op woensdag 11 mei 2016 18:56 schreef i2Them2 het volgende:

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Ik begreep dat er een "satelite"-tornado rond dat systeem hing. En die zou dan tegen de gebruikelijke richting draaien. Maar vaak zijn die satelites veel zwakker en wordt er minder op gelet.
Hier onder een video die het proces kort en bondig uitlegt (rest van de video is ook ZEER interessant).

Storm Spotting Secrets

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An Oklahoma Tornado Rewrites the Rule Book

Overshadowed by the mighty EF4 and EF3 tornadoes that tore across south-central Oklahoma last Monday, May 9, another less damaging twister--from the same thunderstorm--has left seasoned scientists both astonished and fascinated. This tornado, which struck near Roff, OK, was rated an unexceptional EF1 on the Enhanced Fujita Tornado Damage Scale. However, the Roff tornado stands out in several other ways.

—It was an anticyclonic tornado, meaning that it rotated clockwise rather than counterclockwise. A few such twisters probably occur each year, but they account for only perhaps 1% of all U.S. tornadoes—and that’s a very rough estimate, according to tornado climatology expert Harold Brooks (NOAA National Severe Storms Laboratory). In fact, the Storm Data procedures maintained by NOAA include no specific requirement or methodology for reporting whether or not a tornado is anticyclonic.

—It developed in the “forward flank” part of the storm, enveloped in rain-cooled air. “This is the first time I’ve ever heard of a well-developed anticyclonic tornado buried inside the forward-flank core,” said Roger Edwards (NOAA Storm Prediction Center), who has predicted and observed tornadoes for more than 25 years.

—Its damage path was initially estimated to be as much as 13 miles long, as documented in a preliminary storm survey conducted by the National Weather Service in Norman, OK. If confirmed, this path length will likely be a record; I have been unable to find evidence of any other anticyclonic tornado with a path this long. The estimated duration of 35 minutes might also end up as a record-setter for anticyclonic tornadoes. However, reanalysis of the damage could reduce the estimated path length and duration, as the radar signature of the tornado was shorter-lived, according to Gabriel Garfield (University of Oklahoma/CIMMS/NWS), who participated in the storm survey.

he scarcity of anticyclonic tornadoes is not a direct result of the Coriolis effect, which makes tropical cyclones spin cyclonically. The Coriolis force actually has little direct influence on circulations as small as tornadoes (not to mention toilets or other drains that happen to cross the equator). What appears to be the main driver is the wind shear that produces rotating supercell thunderstorms. In the Northern Hemisphere, a blossoming supercell will often split in two, with one cell angling to the right of the mean upper-level wind, spinning cyclonically, and the other angling leftward and rotating anticyclonically. Rightward-moving, cyclonically-spinning cells are the ones better positioned to ingest warm, moist air and grow more vigorously. Thus, most tornadoes are cyclonic, spawned by mesocyclones within cyclonically rotating supercells. (This Wikipedia page includes a nice conceptual diagram of a supercell thunderstorm.) Toward the outer edge of a storm's rear-flank gust front, there can be anticyclonically rotating features; very rarely, one of these will spin up an anticyclonic twister.

What happened in Oklahoma last week doesn't quite fit the classic picture: the anticyclonic Roff tornado developed right in the rain-cooled heart of the storm rather than on its periphery. The Roff tornado was embedded in rain for most or all of its lifespan. "We saw no evidence of it in the gray murk of heavy rain to our [west], nor any suspicious wind shifts," reported Edwards, who was on the same storm photographing the nearby Sulphur tornado. As for what caused the anticyclonic Roff tornado, "we can offer only speculation and conjecture at this point," said Edwards in a blog post. The smoking gun could end up being a stray left-moving storm, evident on radar, that zipped northward and became embedded in the larger, stronger supercell that produced the Roff and Sulphur tornadoes. It's conceivable that this left-moving cell injected some anticyclonic spin into the forward flank of the storm.

Deducing what happened will take some doing, as this storm was more than 50 miles from the Oklahoma City NEXRAD radar. Data from mobile radar, including the RaXPol unit operated by Howard Bluestein and colleagues (University of Oklahoma), may shed some light on the oddly positioned Roff twister. "Having a tornado in that location is worrisome for my team," said Doppler on Wheels chief scientist Joshua Wurman in an email, "because we count on being able to transect cores safely. That's not where we expect to find danger."

Edwards mused: "The odds are extraordinarily tiny of ever seeing another anticyclonic tornado entombed in the forward-flank core of even a violently tornadic supercell. Yet now we know it's possible, and we must be vigilant of that."

Some clockwise pioneers
There are extremely rare cases where a left-moving, anticyclonically rotating thunderstorm generates an "anti-mesocyclone" that spawns an anticyclonic twister, as occurred near Sunnyvale, CA, on May 4, 1998. However, the best-known examples of anticyclonic twisters occur in conjunction with more powerful cyclonic twisters as part of a single supercell thunderstorm, as was the case in Oklahoma last week. Sometimes these are weak, short-lived satellite twisters very close to the companion cyclonic tornado; others are stronger and more separated. Wurman unraveled DOW data for several of these in a 2013 Weather Analysis and Forecasting paper. "Our paper does not include any observations of [forward-flank] anticyclonic tornadoes, so this current one is certainly an outlier," Wurman told me.

One classic case--probably the first anticyclonic tornado ever filmed--unfolded just west of Ames, IA, on June 13, 1976. In this storm, a powerful F3 anticyclonic tornado (the strongest anticyclonic tornado documented to date) closely paralleled the path of an F5 that ripped through the town of Jordan and the nearby countryside. The twisters were only about a mile apart as they moved largely in sync (see Figure 3). The YouTube clip at bottom shows both tornadoes.

A few years later, Ted Fujita and Roger Wakimoto examined the mammoth, nearly stationary supercell that tormented Grand Island, NE, for nearly three hours on June 3, 1980. (This is the storm that inspired the book and movie "Night of the Twisters"). Of the seven tornadoes that emerged that night, three were found to be anticyclonic. "This storm produced the most complex damage patterns imaginable," wrote James McDonald (Texas Tech University) in the Bulletin of the American Meteorological Society. "No one but Ted Fujita could have sorted them out."

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Storm, flood and tornadoes across Alabama and Mississippi
Tens of thousands of people have lost power as severe weather rolled through the southern United States and turned deadly on Monday, January 2, 2017. As of early January 3 (UTC), at least 5 people have lost their lives. Authorities fear the death toll will rise and urge people to pay attention to the warnings and act accordingly.

A low pressure system brought severe thunderstorms to parts of the South on Monday, spinning off several tornadoes, flooding widespread areas and leaving more than 100 000 people without power.

The first line of storms storm hit parts of Texas around 05:00 local time, downing power lines, dropping small hail and sparking at least one house fire. At least 18 000 were without power. The second line of storms rolled in with the sunrise causing flash flooding.

The storms then headed east, causing significant damage to Louisiana, Mississippi, Alabama, and Florida. Much of the damage was caused by flash flooding after a series of storms soaked the region over the past week. Some regions received up to 180 - 230 mm (7 to 9 inches) of rain in just a couple of days.

In Louisiana, a possible tornado reportedly damaged several homes in LeCompte. Severe damage was also reported throughout Avoyaleles Parish, including houses that trees fell through and a building that lost its roof. More than 16 000 customers in the state were without power at one point.

In Alabama, four people were killed in a single home when a tornado hit the town of Rehobeth in the state's south and crashed a tree onto their mobile home.

In Florida, the body of a 70-year-old man was found floating outside his travel-trailer, the Walton County Sheriff's Office said. The death was ruled an accidental drowning.

Downed trees and damaged buildings were reported in at least 28 counties in Mississippi, 15 parishes in Louisiana and 15 counties in Texas, The Weather Channel meteorologist Danielle Banks said.

In Mississippi, a confirmed tornado touched down Monday afternoon near Mendenhall, southeast of Jackson. A second, radar confirmed tornado hit near Mt. Olive, about 13 km (8 miles) northeast of Collins.

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The frequency of large tornado outbreaks in the US is increasing
The frequency of large-scale tornado outbreaks is increasing in the United States, particularly when it comes to the most extreme events, according to research recently published in Science.

The study by researchers including Joel E. Cohen, a visiting scholar at the University of Chicago, finds the increase in tornado outbreaks does not appear to be the result of a warming climate as earlier models suggested. Instead, their findings tie the growth in frequency to trends in the vertical wind shear found in certain supercells—a change not so far associated with a warmer climate.
"What's pushing this rise in extreme outbreaks, during which the vast majority of tornado-related fatalities occur, is far from obvious in the present state of climate science," said Cohen, the Abby Rockefeller Mauzé Professor at Rockefeller University and Professor of Earth and Environmental Sciences at Columbia University, who conducted the research while a visiting scholar in UChicago's Department of Statistics.

Tornado outbreaks are large-scale weather events that last one to three days, featuring several thunderstorms and six or more tornadoes in close succession. In the study, published in the Dec. 16 issue of Science, the researchers used new statistical tools, including extreme value analysis—a branch of statistics dealing with deviations—to analyze observation-based meteorological estimates associated with tornado outbreaks together with National Oceanic and Atmospheric Administration datasets.

The researchers estimated that the number of tornadoes in the most extreme outbreak in a five-year interval doubled over the last half-century. This means that in 1965 the worst outbreak expected over five years would have had about 40 tornadoes, while in 2015 the worst outbreak expected over five years would have had about 80 tornadoes.

"Viewing the data on thousands of tornadoes that have been reliably recorded in the United States over the past half-century as a population has permitted us to ask new questions and discover new, important changes in outbreaks of these tornadoes," Cohen said.

To understand the increased frequency in tornado outbreaks, the researchers looked at two factors: convective available potential energy, or CAPE, and storm relative helicity, which is a measure of vertical wind shear.

Earlier studies had projected a warming climate would increase CAPE, creating conditions favorable to a rise in severe thunderstorms—and potentially tornado outbreaks. But Cohen and his colleagues found the increases in outbreaks were driven instead by storm relative helicity, which has not been projected to increase under a warming climate.

"Our study raises new questions about what climate change will do to severe thunderstorms and what is responsible for recent trends," said co-author Michael K. Tippett, an associate professor at Columbia University's Fu Foundation School of Engineering and Applied Science. "The fact that we didn't see the presently understood meteorological signature of global warming in changing outbreak statistics for tornadoes leaves two possibilities: Either the recent increases are not due to a warming climate, or a warming climate has implications for tornado activity that we don't understand."

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Op vrijdag 20 januari 2017 14:36 schreef Nattekat het volgende:

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Dat is vroeg

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High-risk declarations for severe weather are rare. The last such issuance was June 3, 2014, according to Weather.com and hasn’t occurred in winter since 2008 . Since 1984, 42 percent of tornado fatalities have coincided with such high-risk days, according to the Weather Channel’s Kathryn Prociv.

The region under high risk hasn’t seen such a designation in a decade, the website for U.S. Tornadoes reported.

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Large tornado damages NASA rocket factory in New Orleans

A large tornado ripped through New Orleans and the surrounding area Tuesday, leaving a swath of devastation in its wake and damaging NASA's Michoud Assembly Facility in the city.

It's unclear how much damage the facility, which is helping to manufacture NASA's next mega-rocket, sustained.

"At 11:25 a.m. CST, a tornado impacted NASA’s Michoud Assembly Facility in New Orleans. At this time, only minor injuries have been reported and NASA employees and other tenants are being accounted for," NASA spokesperson Tracy McMahan said in an email.

SEE ALSO: Over a dozen dead as violent storms slam Southeast U.S.

"There is still a threat of severe weather in the area and emergency officials are continuing to monitor the situation to ensure the safety of onsite personnel," McMahan added.

"The onsite Michoud emergency response team is also conducting damage assessments of buildings and facilities."

During the space shuttle era, Michoud was responsible for assembling and testing the external tanks used to store the propellant that would power shuttles into orbit.

Today, Michoud is helping to test and build hardware for NASA's Space Launch System (SLS) rocket and the Orion spacecraft, designed to deliver humans to deep space destinations like the moon and Mars in the coming decades. The SLS rocket is slated to be the most powerful the agency has ever built.

NASA is not yet sure whether any of the spacecraft hardware at Michoud was damaged during the storm.

Michoud Assembly Facility Tornado damage Feb 7 2017

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Op woensdag 8 februari 2017 10:16 schreef Pannenkoekenmix het volgende:
Volgens mij kun je aan het formaat helemaal niet zien hoe sterk de tornado was.

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Op basis van de schade dan denk ik ook wel dat het een F2 moet zijn geweest.

En die mensen die daar staan te filmen zijn inderdaad echt niet goed bij hun hoofd.

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Storm damage reported in Bulloch, Effingham counties

Reports of storm damage are coming into the WTOC newsroom from a fast-moving system that rolled across our area between 3 and 5 a.m. Thursday morning.

We are hearing of power outages, multiple trees down and at least two homes damaged with occupants possibly trapped inside on Old River Road South four miles East of Stilson in Bulloch County.

Bulloch County EMA has confirmed that at least seven people were injured in homes on Lilly Hagen Road and Old River Road South. One person was flown by LifeStar to a hospital in Savannah with serious injuries, and six others were driven to East Georgia Regional in Statesboro.

Storm damage and power outages have also been reported in Effingham County. A pumphouse was reportedly destroyed, homes damaged and numerous trees and power lines were blown down in Pineora.

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Radar detecting possible tornado 4 miles northeast of Wharton. Moving NE toward Needville.

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Op dinsdag 14 februari 2017 15:38 schreef Nattekat het volgende:

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Is dat live?

twitter:

RRstormchasers twitterde op dinsdag 14-02-2017 om 15:43:22 #Tornado warning includes downtown #Houston. Be prepared to seek shelter! #txwx https://t.co/hdgXWPoll1 reageer retweet

twitter:

BrianJamesNBC5 twitterde op dinsdag 14-02-2017 om 16:16:03 NOT DFW: A well-pronounced area of rotation just moved through the south side of downtown #Houston. #txwx https://t.co/RmRpMd1lMm reageer retweet

twitter:

Breaking911 twitterde op dinsdag 14-02-2017 om 16:34:16 BREAKING: NWS Houston Reports Confirmed Tornado Over Houston Ship Channel And Cloverleaf Texas Moving East Now reageer retweet

twitter:

breakingweather twitterde op dinsdag 14-02-2017 om 16:38:14 Several roofs of homes & businesses were blown off in Stafford, TX, emergency management said. Multiple sightings of funnel cloud reported reageer retweet

twitter:

ReedTimmerAccu twitterde op dinsdag 28-02-2017 om 13:56:47 Expansive enhanced risk for severe weather, incl. potential for strong tornadoes from Ozarks thru southeast 1/2 of… https://t.co/u3JpdUY4HB reageer retweet

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Tornadoes kill three in midwest
At least three people have been killed on Tuesday, February 28, 2017, as severe weather outbreak, including heavy rain, strong winds, and at least 7 tornadoes, rip through the US Midwest. As of March 1 at 07:00 UTC, the NWS has issued Flash Flood, Flood, Severe Thunderstorm and Tornado Warnings for the states of Illinois, Ohio, and Indiana. Events that took place in Illinois were extremely rare for February.

According to the National Weather Service, tornado spotters reported 23 twister sightings in Illinois, Missouri, Iowa, Tennessee and Indiana on Tuesday evening.

A large and dangerous tornado touched near Ottawa, 80 km (50 miles) southwest of Chicago, killing one person after the twister uprooted a tree. There are reports of minor injuries at an Ottawa nursing home.

At least a dozen vehicles, including a semi-truck, were blown off Interstate 55 near Perryville, Missouri, some 130 km (80 miles) of St. Louis, after a tornado touched down in the area. At least one person died and several were injured. Media reports mention 8 to 10 badly damaged buildings and structures. Perry County Clerk Jared Kutz says emergency management officials in the county aren't certain it was a tornado, but Missouri Gov. Eric Greitens says in a statement that there are confirmed reports of a tornado.

The third person was killed in Crossville, Illinois. He was found in a field behind his heavily damaged home. His wife sustained injuries and was taken to the hospital.

02-28-2017 Standard, IL - Tornado

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Ravage in middenwesten VS na reeks tornado's

Enkele dagen na een reeks tornado's in het middenwesten van de VS, proberen inwoners in de staat Illinois de draad weer op te pakken. Het is er een ravage. "Ik hoorde een keiharde wind en een explosie van glas", zegt Debbie Loughridge, inwoner van Naplate, tegen persbureau AP. "Het was een oorverdovend geluid, alsof er een trein aankwam."

In Naplate staan ongeveer 200 huizen, zeker een kwart is verwoest, waaronder het huis van Loughridge. Toen de storm overtrok verschool ze zich met haar zoon in een badkuip. Ze werden uiteindelijk door de brandweer uit het huis bevrijd; een deel van het dak van hun huis was weggewaaid.

Ook andere plekken werden getroffen. In het noorden van Illinois kwam een man onder een omgewaaide boom terecht en overleed. En in de staat Missouri werd een aantal auto's van een schrootplaats geblazen. Een van de voertuigen raakte een automobilist, ook die man kwam om het leven.

Tornado's raasden ook over Tennessee en Iowa, maar volgens een brandweerwoordvoerder in Perryville viel het daar al met al mee met de schade. "Volgens mij mogen we van geluk spreken dat er niet nog meer slachtoffers zijn gevallen door deze ramp."

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Perryville tornado rated EF-4, the first violent tornado of 2017

The National Weather Service has upgraded the Perryville, Missouri tornado of February 28, 2017 to EF-4 today. This makes it the first violent tornado of 2017. The event lasted an astounding 1 hour and 2 minutes and was the longest track tornado in the coverage area of NWS Paducah since another EF-4 tornado back on April 22, 1981.

The tornado quickly became violent reaching EF-4 intensity and leveling 5 homes, as well as other structures, just west of I-55, about 5.6 km (3.5 miles) northwest of Perryville, Missouri. This is in the Kyle Lane and County Road 806 area, NWS explains.

Numerous uninhabited cars from a salvage yard were blown into or over I-55. The lone fatality occurred when an I-55 southbound vehicle was intercepted by the tornado.

As the tornado tore east, it caused the area of greatest home and property destruction 4.8 km (3 miles) north of Perryville, in the vicinity of U.S. Highway 61 and Moore Drive.

Three homes were leveled on the west side of U.S. Highway 61 with dozens of other homes and structures destroyed. Several of the injuries occurred in this area. In addition to the leveled homes in Perry County, at least 100 other homes received moderate to major damage.

As the tornado continued east across Perry County, it leveled or nearly leveled 2 additional homes and destroyed numerous other homes and structures. The tornado reached its greatest width as it approached the Mississippi River where a damage swath 965 m (0.6 miles) wide was measured.

The tornado damage path also exhibited multiple vortex characteristics at this point, yielding three distinct convergent areas within the parent vortex. This was also indicated via ground striations, or disturbance marks to bare ground, just west of the Mississippi River.

The twister then ripped across the southern tip of Randolph County Illinois just south of Rockwood and continued its ENE path across Jackson County, Illinois passing just south of Ava, Illinois and immediately south of Vergennes, Illinois.

Many thousands of large trees were snapped and uprooted, and dozens of homes and other structures were damaged or destroyed across Jackson and Franklin Counties.

The tornado remained very intense and wide (at least 0.5 km / 1/3 mile) nearly leveling a home as it passed between Elkville and Dowell, Illinois and into Franklin County with unabating intensity. A house was leveled 2.8 km (1.75 miles) south of Mulkeytown.

Very soon thereafter the tornado began to rapidly weaken, before dissipating 2.9 km (1.8 miles) southwest of Christopher.

The tornado lasted an astounding 1 hour and 2 minutes and was the longest track tornado in the coverage area of NWS Paducah since another EF-4 tornado back on April 22, 1981.

Quick facts:

Rating: EF-4
Estimated peak wind: 289 km/h (180 mph)
Path length /Statute/: 81.1 km (50.4 miles)
Path width /Maximum/: 965 m (0.6 miles)
Fatalities: 1
Injuries: 12

Start date/time: February 28, 19:55 CST (March 1, 01:55 UTC)
Start location: 7.7 km (4.8 miles) WNW of Perryville, Missouri

End date/time: February 28, 20:57 CST (March 1, 02:57 UTC)
End location: 2.9 km (1.8 miles) SW of Christopher, Illinois

Today in St. Louis: Perryville Tornado

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The 2017 tornado season is running far ahead of average
The highly progressive pattern that’s kept midlatitude storms shuttling across the United States all winter has given an early boost to the U.S. tornado season of 2017. Such a progressive pattern is important but not sufficient for producing early-season severe weather. Even if upper-level conditions favor severe weather, there may not be enough time between midlatitude storm systems for unstable air to flow back into place from the Gulf of Mexico. This year, however, the Gulf and Caribbean have been consistently warm, which has helped generate plenty of warm, moist air for midlatitude storms to access. In records back to 1981, this is the first year in which sea surface temperatures averaged across the entire Gulf never dropped below 73°F, as discussed by Eric Berger at ArsTechnica and shown in Figure 5 below (thanks to WU member Mark Cole for this tip). As of Monday, SSTs over the western Gulf were running 1°C - 2°C (1.8-3.6°F) above the seasonal norm.

Thus far in 2017, NOAA/SPC has logged 268 preliminary tornado reports. This is roughly double the average of 133 reports racked up by March 5 over the preceding 11 years (2005-2015). This year also stands out in a longer-term perspective, even after you “inflation-adjust” the data back to 1954 to account for the increased tendency since then for a given tornado to be spotted, chased, photographed, videotaped, etc. After the inflation adjustment, this year’s preliminary total of 228 tornado reports (see Figure 6 below) compares to a long-term average of just 69 reports by this point in the year.

twitter:

MJVentrice twitterde op dinsdag 07-03-2017 om 11:06:20 Yesterday's 32 reported tornadoes was the most in the month of March since the infamous Mar 2, 2012 outbreak, which… https://t.co/ZoUCGYlMls reageer retweet

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Major pattern shift will usher in severe weather

Marginally severe storms are possible across parts of Indiana and Illinois on Monday and the Tennessee Valley on Tuesday, as a spoke of energy rotates around a upper-level low sweeping through eastern Canada. The bigger event will come later this week as the upper-level pattern shifts back toward a Pacific-dominated regime. Several inches of rain and major mountain snows are headed for parts of California, Oregon, and Washington as one storm swings through on Tuesday/Wednesday and a stronger one around Friday/Saturday.

The first upper-level wave in this sequence will reach the Great Plains by late Thursday. Low-level moisture will be rapidly returning from the Gulf, but it’s not yet clear whether enough instability will be on hand to support severe weather. If there is, the focal point would be along a strong dryline expected to be over the High Plains of western KS/OK/TX by late Thursday. A more robust severe threat appears likely for Friday over eastern TX/OK into AR/LA, and on Saturday across parts of MS/AL/GA/FL, as the system marches east into more-unstable air. The NOAA/NWS Storm Prediction Center has outlined both regions with a 15% likelihood of severe weather for Friday and Saturday. I’d expect those odds to rise as the timing and locations become clearer through the week.

The next multi-day round of severe weather will likely erupt with the second wave in the series, in tandem with the gradual establishment of a upper-level trough in the western U.S. Models are struggling with the evolution of these features, although recent runs of both the GFS and ECMWF models tend to agree on a pattern that would favor severe thunderstorms over the Southern Plains of TX/OK for at least a day or two early next week.

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The NOAA/NWS Storm Prediction Center has outlined both regions with a 15% likelihood of severe weather for Friday and Saturday. I’d expect those odds to rise as the timing and locations become clearer through the week.

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Op woensdag 29 maart 2017 04:12 schreef crystal_meth het volgende:

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http://edition.cnn.com/20(...)ash-texas/index.html

Tornado Intercept (Inside a Weak Tornado) Lena, La (04/02/2017)

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Storm chasers drove into a tornado on purpose. Then their peers berated them.

Storm chasers who intentionally drove into the teeth of a tornado Sunday are now facing scathing blowback from their peers. The chasers got too close to the twister, the critics say, setting a dangerous example.

Storm chasers converged in northern Louisiana on Sunday as the National Weather Service declared it a high-risk zone for violent thunderstorms.

Later, the Weather Service posted a “particularly dangerous situation” tornado watch — reserved for the rare circumstances in which conditions are favorable for the large, long-track tornadoes that some chasers salivate over.

Such monsters never formed Sunday, but several smaller tornadoes spun up in northern Louisiana, including one that killed a mother and daughter in their mobile home. When a small tornado surfaced near the town of Lena, about 25 miles northwest of Alexandria, storm chaser Bart Comstock and his crew showed no restraint.

After spotting the tornado, video from Comstock and his crew (below) shows the chase vehicle take off at a high speed straight for the twister — as its engine roars (caution: video contains expletive).

A second camera view from the same vehicle (watch from 1:45 onward) shows the driver with one hand on the steering wheel, the other with a camera photographing the storm.

“We’re in it, we’re inside the tornado right now,” one of the crew says while another chaser is heard laughing in the background.

The car is nearly blown off the road, when the chasers shout excitedly: “Whoa! Oh!”

After the encounter, one of the crews boasts, tweeting: “OMG Just took a DIRECT HIT from a #tornado in Lena, LA. Got great footage, mult cameras.”

But the act of intentionally driving into a tornado, rather than watching it from a safe distance, did not sit well with some of their fellow storm chasers.

Victor Gensini, a professor of meteorology at the College of DuPage — who leads student chasing tours, excoriated Comstock in a Twitter conversation.

“You’re doing it wrong,” Gensini tweeted. “Takes direct hit and then brags about having video, Argh!”

Comstock defended himself. “Calculated risk on a very weak tornado,” he tweeted. “Wait to see the video before you judge. To each their own.”

Gensini replied: “I don’t need to see video to understand that you made a bad decision.”

Comstock refused to back down, responding: “I absolutely made the decision and it was mine to make. If you’re not a fan of my chase style you’re always welcome to unfollow me.”

Other storm chasers piled on in criticizing Comstock.

“This is not a badge of honor, nor is it a good example. Bragging about it is tone deaf,” tweeted Barbara Mayes Boustead, a meteorologist with the National Weather Service, who storm chases in her spare time.

“Irresponsible,” tweeted Jeff Frame, a professor of meteorology at the University of Illinois and storm chaser.

“I try not to be judgmental,” added Matt Lanza, a meteorologist in Houston. “But storm chasers driving INTO a tornado essentially laughing all the way. That’s … not a good look.”

The dispute has taken on additional heft as the chaser community comes to grips with the loss of three chasers who died in a traffic collision in Texas last week. One of the chasers ran through a stop sign before the accident occurred

quote:

Op woensdag 5 april 2017 18:38 schreef Houtenbeen het volgende:
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Weerplaza twitterde op donderdag 06-04-2017 om 07:14:55 In Nederland nu rustig, maar zwaar weer in het zuidoosten van de VS. Afgelopen 24 uur bijna 200 meldingen van grote… https://t.co/Ix92bdM2ac reageer retweet

twitter:

NWSMemphis twitterde op woensdag 03-05-2017 om 15:35:19 BREAKING NEWS: The levee has failed on the Black River at Pocahontas. This is a FLASH FLOOD EMERGENCY! Seek higher… https://t.co/0GV8NGFRGA reageer retweet

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Op donderdag 18 mei 2017 09:24 schreef Houtenbeen het volgende:
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twitter:

Jeff_Piotrowski twitterde op donderdag 18-05-2017 om 14:00:23 High Risk today with all modes of severe including long track very destructive tornado's. #okwx #kswx #tornado https://t.co/jkouduJU48 reageer retweet