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Polar vortexMonstrous whirlpool in parish Dviete, Latvia swallows everything in its path. Swallowing everything dragged towards its direction, this monstrous whirlpool looks as if a plug has been pulled from the ground beneath.
Polar vortex arrives for mid-July
July 9th, 2014 at 9:45am | Last Updated at 1:57pm
Many of the cold weather outbreaks this past winter were attributed to something called a Polar Vortex. This is where a flow pattern establishes in the upper atmosphere that draws cold arctic air down across the Canadian Prairies and down into the American mid-west and the Great Lakes region. The summer-time version of the Polar Vortex is about to arrive next week, bringing unusually cold air to the Great Lakes and much of central North America.
Climatologically the middle part of July is usually the warmest time of year in Northern Ontario. Temperatures typically climb into the mid 20s during the warmest time of the day, while overnight lows remain above +10°C.
So this Polar Vortex couldn’t arrive at a worse time. Instead of warm summer-like conditions it will feel more like fall. Temperatures are likely to be 5-10°C below normal. This will keep daytime highs buried in the teens with overnight lows in the single digits. This cold air is expected to move as far south as Texas where record low temperatures could be broken.
When you average the temperatures we have seen for the first 9 days of July we are already 3°C below normal. Adding on this upcoming cold outbreak will likely cause the entire month to end up below average. This would mean that six of the first seven months of 2014 have brought below normal temperatures in Northern Ontario - with only June being near normal.
When you compare the climatological factors at play, it is interesting to note that we can compare 2014 to previous years. 2002 and 2009 had many factors similar to this current year and if that trend continues it could mean good news for August. In those years the hottest weather waited until that last month of summer to arrive – let’s hope that’s the case again this year.
So enjoy the warmer temperatures expected later this week because it appears we are in for an unseasonably cold run for next week.
Polar vortex in July - how odd?
Its a result of Typhoon in Japan - oddly enuf.
Rare snowstorm slams Rockies states, South Dakota
It's still summer, but a snowstorm blanketed parts of Wyoming, South Dakota, Montana and Colorado, setting early snowfall records in some places, covering lawns and flower gardens and providing a preview of what is to come.
The snowstorm dumped up to 20 inches of snow in parts of Wyoming on Wednesday and Thursday and sent overnight temperatures plummeting into the 20s in some areas.
While snow in September is rare, it isn't unusual for local residents used to wild swings in the weather.
"I don't mind it; it is what it is," said Deann Meyer of Buffalo, Wyoming, where up to 10 inches of snow fell. "It's going to be 80 next week. That's what the weather says. Of course, that could change."
Still, it was the earliest snowfall on record for parts of Wyoming and southwest South Dakota. Temperatures hovered around freezing in Denver, forcing many gardeners to wrap their plants for protection.
Hard frosts were reported in western Montana. Kalispell reported a record low of 23 degrees Friday morning while Missoula's record low was 25, compared with 28 in 1988.
Chuck Baker, meteorologist with the National Weather Service in Riverton, Wyoming, said the blast of wintry weather originated in the northern reaches of Canada. "It was pretty potent for this time of year," Baker said.
The heavy, wet snow snapped off tree branches and caused power outages in Buffalo and the surrounding area.
Some roads and highways had slick spots Friday morning. Going-to-the-Sun Road in Glacier National Park in Montana was closed temporarily earlier in the week, but otherwise travel was not hampered.
The National Weather Service reported 20 inches of snow falling in the Bighorn Mountains in north-central Wyoming.
Eight inches fell in Custer, South Dakota.
The 3 to 5 inches that fell in Cody, a busy summer tourist town in northwest Wyoming, is the earliest recorded snowfall there since records were kept in 1915. The previous recorded earliest snowfall in Cody was Sept. 12, 1970.
Just under an inch fell in the Rapid City, South Dakota, area, breaking the previous record set on Sept. 13, 1970, for the earliest snowfall.
Boulder, Colorado, also received snow — a year after being hit by a devastating flood from heavy rain.
What is driving the increasingly weird behavior of the polar jet stream?
If you guessed climate change, you might be right
A big link between climate change and severe weather may be lurking 30,000 feet above your head. More and more scientists are interested in the links among the increasingly weird behavior of the polar jet stream and the disappearance of ice and snow in the Arctic and other extreme weather trends. The linkage is suggestive, though not proven, but if true would clearly demonstrate that what happens in the Arctic affects more than just polar bears.
What's happening to the polar jet stream
One of the biggest drivers of weather in North America is the polar jet stream, a ribbon of high-speed winds that flows east from Alaska, across the U.S. and Canada, and over the Atlantic Ocean towards Europe. The jet stream alters weather conditions below it by moving warm and cold air masses around, allowing weather systems to migrate across land and sea. The jet stream's path undergoes some natural variation, but has gotten downright loopy in recent years, according to scientists.
"I've been doing meteorology for 30 years, and the jet stream the last three years has done stuff I've never seen," Jeff Masters, meteorologist at Weather Underground, said in 2013. "The fact that the jet stream is unusual could be an indicator of something. I'm not saying we know what it is."
Rutgers University atmospheric scientist Jennifer Francis thinks there is a clear climate change factor in the jet stream's wobbliness: the warming of the Arctic. Temperatures are rising in the Arctic regions faster than anywhere else in the world, an effect called "Arctic amplification" that may be due to the fact that as sea ice melts it exposes darker water that absorbs more heat then the reflective ice. As the Arctic warms more quickly than other regions, this lessens the temperature gradient between the equator and the North Pole, a key factor governing the behavior of the polar jet stream.
How? A weakening temperature gradient slows the jet stream, which has the effect of making it wavier — or so goes the theory. Francis compares the situation to a river flowing down a mountain and out towards the coast. While it's moving quickly down an incline, the river takes a more straightforward route; when it slows, as the base of the mountain shallows approaching the coast, the river naturally adopts a more wandering path. Similarly, a slower jet stream is more likely to be wavy, with more peaks ("ridges") and dips ("troughs").
How a wavier jet stream equals wilder weather
And a wavier jet stream has historically been associated with extreme weather. In one study published in Nature Climate Change in June 2014, University of Exeter mathematician James Screen and University of Melbourne earth scientist Ian Simmonds combed through historical weather data going back to 1979 and focused on 40 extreme weather events, from heavy rainfall to droughts, cold snaps, and heat waves. In general, they found that large waves in the jet stream tend to coincide with such events.
Jet stream waviness has also been linked to all sorts of extreme weather events in recent years. Francis has argued that the left hook that Hurricane Sandy took (sending it towards New Jersey) was due to a blocking ridge. And the 2013-2014 winter, which was unusually warm in Alaska, unusually dry in California, and unusually cold across the Midwest and East Coast, occurred as the jet stream stayed in a holding pattern, in a shape that had a big ridge to the west and a deep trough to the east.
"It's a great example of the kind of pattern we expect to see more often," Francis says.
Why there's complexity, uncertainty, and chaos
Not every scientist is on board with the theorized connection between the jet stream and extreme weather. Colorado State University atmospheric scientist Elizabeth Barnes took a look at jet stream waviness between 1980 and 2011, and proposed that the increased waviness that Francis and other scientists were seeing is "likely an artifact of the methodology" they used.
Barnes' analysis of the data showed no wide trends in jet stream speed or increased episodes of blocking ridges over that 30-year period. But Francis and other scientists point out that the extreme type of Arctic melting we're seeing today has only kicked into gear within the last decade, so looking at data going back thirty years might muffle the signal of the changes that are currently happening.
"I'm pretty much on the middle ground here," says NOAA scientist James Overland. "We've seen more severe weather in the mid-latitudes" — the zones between the tropics and the polar regions — "in the last 5 years or so, and we also know that the Arctic is changing and warming up quite a bit. But the uncertainties are in understanding the mechanisms that tie the two together. The timescale is very short, [making it harder to] totally prove that there is a connection… and weather is very chaotic to start with, so it's hard to isolate what the Arctic contribution would be."
Even if the changing jet stream is found to influence weather trends, individual weather events don't typically stem from a single cause. In an unusual 2010 snowstorm that buried Washington, DC under three feet of powder, for example, there was cold Arctic air ferried south by a dip in the jet stream, but there was also an El Nino event bringing moisture laterally, across the southern U.S. "It was the two acting together," Overland says. "If you'd just had one or the other it wouldn't have been so extreme."
Overland doesn't really see a consensus emerging in the next few years; the problem isn't just a lack of data, but in the differences between computer models and climate scientists' own interpretations. The jet stream might not end up being the smoking gun; there are other proposed mechanisms that tie climate change and wild weather together. Still, "we believe that we're going towards a nearly sea ice-free Arctic in the next 10-20 years," says Overland. "The question now is: Do you wait for more perfect information, or do we act on incomplete information?"
Arctic Blast via Polar Vortex to Chill 42 US States
By Kristina Pydynowski, Senior Meteorologist
November 8, 2014; 6:14 PM ET
An overview of the weather across the North Central region is given in the above AccuWeather.com video.
As the polar vortex gets displaced to the south, the door will open for arctic air to plunge over the most of the United States as the new week progresses.
Only the Southwest, Hawaii, Alaska and South Florida will escape the grip of the upcoming arctic blast that the polar vortex can be blamed for.
"The polar vortex is a large pocket of very cold air, typically the coldest air in the Northern Hemisphere, which sits over the polar region," stated AccuWeather.com Senior Meteorologist Alex Sosnowski.
"Occasionally, this pocket of very cold air can get dislodged farther south than normal, leading to cold outbreaks in Canada and the U.S."
Polar vortex unleashed: Severe cold snap likely in U.S. next week
A punishing blast of Arctic air will plunge into the northern half of the Lower 48 in five to seven days, dispensing some of the most frigid air since 2014 or 2015 in some areas.
“[The] upper-level atmosphere configuration [is] very similar in scale and magnitude as infamous January 2014 #PolarVortex”, tweeted Ryan Maue, a meteorologist with WeatherBell Analytics.
Computer models are unanimous in predicting that such a cold wave will occur, although they differ some on exactly how cold and how far south and east the Arctic air will penetrate. It is unlikely that this cold wave will be as intense as the January 2014 event because it is happening earlier in the winter and less snow is on the ground in North America (snow cover acts like a freezer and helps cold air masses stay cold when they exit the Arctic).
The bitter cold air is expected to first arrive in the northern Rockies and northern Plains on Sunday. It should reach Chicago on Tuesday and the northeast United States by Wednesday or Thursday.
While subject to change, the GFS model predicts temperatures from Chicago to western Montana to be 30 to 50 degrees colder than normal next Wednesday morning.
The past couple years TWC has called Arctic Blast a Polar Vortex to make it sound scary. Scary? LOL! It makes me think of the Christmas movie - POLAR EXPRESS
It more Climate hoax hype
I pray President Donald Trump will correct this crap - QUICKLY
Below-zero temperatures to expand across US during 3rd week of December
A new batch of arctic air will blast into the United States in the wake of a cross-country storm with snow, ice and rain this weekend.
The main thrust of the new arctic blast will be felt over the Central states from Saturday night to Monday.
Fresh, deep snowcover will create ideal conditions for the cold air to spread southward from Canada to the northern and central Plains and part of the Midwest. As a result, the air coming into these locations will be even colder than that of this week.
This weekend, actual temperatures will plummet at night to minus 30 to 20 degrees Fahrenheit from portions of Montana and Wyoming to parts of the Dakotas, Minnesota and Wisconsin. Temperatures dipping to between 20 and 10 below zero are in store from parts of Colorado to portions of Nebraska, Iowa and Illinois.
Subzero nighttime temperatures will extend as far to the south as parts of New Mexico, Texas, Oklahoma, Kansas, Missouri, Indiana and Michigan.
After plummeting to near zero by Sunday morning, temperatures may struggle to stay above zero on Sunday afternoon around Chicago, according to AccuWeather Meteorologist Bill Deger.
"Fans heading to the matchup between the Bears and Packers may experience the coldest NFL game ever played at Soldier Field during Sunday afternoon," Deger said. "AccuWeather RealFeel® Temperatures will average close to 10 below zero."
Even during the day, the movement of air ranging from a slight breeze to strong winds combined with other conditions will push AccuWeather RealFeel Temperatures to dangerous and even life-threatening levels for those without shelter or not properly dressed. At times, RealFeel Temperatures may dip to 25 degrees lower than the actual temperature.
Winter storm hits U.S. South with rare snowfall
January 6, 2017
ATLANTA (Reuters) - A storm packing heavy snow, sleet and freezing rain hit the U.S. South on Friday, bringing winter weather to a region unaccustomed to it and leading to traffic snarls and widespread school closures.
As much as 8 inches (20 cm) of snow and 1 inch (3 cm) of sleet was expected to fall on a large swath of the United States from northeast Louisiana to southern Pennsylvania, according to the National Weather Service.
The service issued winter storm warnings stretching from Louisiana, across the South and into the East Coast. Police from Oklahoma and Arkansas reported scores of accidents on roads where a few inches of snow had fallen.
"If you don't have to travel, don't travel," said Matthew Grantham, a National Weather Service meteorologist in Alabama. Conditions will worsen after dusk on Friday, he added.
The heaviest snowfall was expected for Friday night into Saturday with southern Virginia and north-central North Carolina being the hardest-hit areas, the service said.
Ahead of the winter storm, Atlanta residents packed into stores to stock up on essentials.
“I shouldn’t have waited to the last minute,” said Showanda Torres, 29, of the East Atlanta Village neighborhood, as she pushed her 3-year-old son in a shopping cart at a grocery store.
"The shelves are getting picked clean," she said.
The storm also affected U.S. air travel. As of 2:30 p.m., there were about 370 flight cancellations at Atlanta's Hartsfield-Jackson Atlanta International Airport, one of the nation's busiest, according to tracking service FlightAware.com.
City officials called for staggered departures to avoid Friday evening traffic congestion. Schools were asked to release students at lunchtime.
The move followed a disastrous response to winter weather in January 2014, when thousands of commuters sat in gridlock for hours on frozen highways around Atlanta and many children were stuck at schools.
States of emergency were declared for 79 counties in Georgia and all of Alabama. Arkansas Governor Asa Hutchinson shut state offices for non-essential personnel.
North Carolina Governor Roy Cooper also declared a state of emergency as the storm is expected to bring significant snowfall to his state, particularly in the central region.
The hazardous weather has forced the postponement of ceremonial inauguration events scheduled this weekend for Cooper, who has already taken office.
"The number one thing is making sure the people of North Carolina are safe," Cooper told a news conference on Friday morning. "You can do that by staying home."
Springlike warmth to challenge records across eastern US next week
It will feel more like spring across part of the eastern United States next week as temperatures briefly soar to record-challenging levels.
Residents from Atlanta to Nashville to Washington, D.C., will trade in winter coats for t-shirts by midweek.
A major storm will take shape over the center of the country by Tuesday. Unseasonable warmth will then build on the southeastern side of the storm.
“Even though Punxsutawney Phil called for six more weeks of winter, to many in the Southeast it will feel more like mid-April than early February for a brief period next week,” AccuWeather Meteorologist Faith Eherts said.
Tuesday is shaping up to be the warmest day of the stretch, when records that have held since the 1900s could be in jeopardy throughout the Southeast.
“Throughout Maryland and Virginia, high temperatures on Tuesday will reach upwards of 15 degrees above average,” Eherts said. “Farther south, they may exceed 20 degrees above average.”
Widespread highs in the middle to upper 70s F are in store across the Deep South, with 60s and lower 70s in store for much of the Ohio Valley and southern mid-Atlantic.
“Temperatures will soar into the 60s as far north as Washington, D.C,” Eherts said.
A few of the cities that will challenge record warmth include New Orleans; Montgomery, Alabama; Atlanta; Jacksonville and Pensacola, Florida; Charlotte and Raleigh, North Carolina; Nashville; and Washington, D.C.
The bulk of the warmth will fail to reach much of the interior Northeast and New England, where periods of snow and ice can occur early next week.
Most of Tuesday will be dry and sunny across the southern Atlantic Seaboard, which is great news for those who hope to enjoy the brief spurt of warmth by hiking, biking or walking.
Behind the passage of rain and thunderstorms late Tuesday and Wednesday, warmth will be whisked away and temperatures will fall back to within a few degrees of average across the Southeast.
The brunt of the chill will sweep across the Midwest and Northeast late next week as temperatures plummet to unseasonably low levels.
Temperatures may rebound once again across the Southeast and perhaps the mid-Atlantic as quickly as next weekend.