Jet Stream Dip Has Brought Record Snow This Spring.
© NOAA |
Duluth, Minn., for example, has seen 51 inches (130 centimeters) of snow this April. That's not only the most snow the town has seen in any April - breaking the old mark of 31.6 inches (80 cm) - but the most snow the town has received in any month, ever, according to government records. As of Monday (April 22), a total of 995 snowfall records have also been broken so far this month, according to AccuWeather. Over the same time period last year, 195 snowfall records had been broken.
More than 91 percent of the upper Midwest also has snow on the ground as of today (April 24), meteorologist Jason Samenow wrote at the Washington Post's Capital Weather Gang blog. "Snow cover in the previous 10 years on this date hasn't even come close to reaching this extent (ranging from 19 percent to much lower)," he wrote.
So why has spring failed to take hold? Blame the jet stream.
The record snow and below-average cold is due to a trough or dip in the jet stream, which has brought blasts of freezing air as far south as the Mexican border, said Jeff Weber, a scientist with the University Corporation for Atmospheric Research in Boulder, Colo.
Whence the snow?
This dip in the jet stream has also brought moisture from the Pacific to the Eastern Rockies. Boulder, Colo., for example, saw 47 inches (119 cm) of snow in April, breaking the old record of 44 inches (112 cm).
From the dip, the jet stream then swoops up to the north toward Minnesota, bringing new moisture with it from the Gulf of Mexico, Weber said. That has made for snowy conditions throughout the region.
This persistent trough has largely stayed in place during much of April, due in part to a stubborn mass of warm air over Greenland and the North Atlantic, Weber said. A similar system was also responsible for therecord cold seen in March throughout much of the Eastern United States.
This mass of air has blocked the normal eastward progression of the jet stream, which normally brings warm air from the south and west into the central United States. Instead, this "buckled" jet stream has been stuck in place, bathing the Rockies and Upper Midwest in cold, and often moist, air, Weber said.
Warming up
But now, the mass of warm air over the North Atlantic is finally dissipating, and higher temperatures are expected by this weekend from Colorado to Minnesota, Weber said. While temperatures have recently dipped into the single digits (below 10 degrees Fahrenheit, or minus 12 degrees Celsius), they should reach above 80 F (27 C) by the weekend throughout much of this region, he said. [6 Signs that Spring Has Sprung]
WATCH: May Snow Piles Up.
This will lead to a lot of melted snow, which could cause some of the worst flooding ever seen in the Upper Midwest, Weber said.
The persistent cold has helped tamped down severe weather and tornadoes, which thrive on the interaction of warm, moist air with cold, dry air, Weber said. However, he expects to see a lot more severe weather and tornadoes in the near future, particularly in the Southeast. - Live Science.
US Headed For The Coldest Spring On Record.
At the two-thirds mark for meteorological spring, 2013 was the second coldest spring on record, slightly warmer than 1975.Data is from here : Index of /pub/data/ghcn/daily/hcn/ |
But 1975 had an unusually warm May at 17C. The two warmest May’s were in 1934 and 1896.
The forecast for the first two weeks of May is well below normal, so odds are that the spring of 2013 will be the coldest on record in the US. This is what Fort Collins looked like at 7pm today (May 1.)
- Real Science.
Record Cold In Interior Alaska - Heading Into The USA, Agriculture At Risk.
reader "agimarc" writes: As with the Lower 48 states, spring is late and cold here in central Alaska. Fairbanks reported a record low of 2 degrees F above zero Sunday, breaking the previous record of 8 from 1924.Story here: http://www.adn.com/2013/04/29/2883299/interior-alaska-sees-record-breaking.html
Here in Anchorage, looks like we are around 3 - 4 weeks late with ice of local lakes and snow off the ground. Winter was not particularly hard, but it all changed with a very cold April. And at this point it does not appear things will be warming up soon. So much for manmade global warming due to carbon dioxide emissions.
Yes, have a look at the image above.
Click HERE for a complete list of record lows for Alaska in the past 7 days, where 996 new record lows were set
And the cold is now creeping into the USA, look at the difference between Denver and Kansas City:
Expect a whole new crop of record lows for the USA, and some serious issues to develop with agriculture in the nation's breadbasket as a result.
Only 5% Of Corn Crop Planted
This in contrast to last year at this time of 49% of the corn crop planted and the five year average of 31%The Weather Channel picked the wrong year to name winter storms, the snow and cold may be their Achilles Heel (h/t to Steve Goddard):
Winter Storm Achilles: Snow and Cold Kick Off May | Weather Underground
- WUWT.
Historic Snowstorm Potential For Omaha To Minneapolis.
The same storm bringing heavy snow to Denver and Cheyenne Wednesday has the potential to bring a swath of heavy, wet snow from eastern Nebraska to northwestern Wisconsin and the western Upper Peninsula of Michigan by Thursday.The storm, like many in recent weeks, seems to be ignoring the date and, if all the right pieces were to fall into place, could bring 6 inches to a foot of snow on its northwestern flank over the central Plains into the Upper Midwest.
As of the middle of the day Wednesday, the northwest Iowa counties of Lyon and Sioux have received between 3 and 5 inches of snow. That snow is forecast to expand eastward and southward later Wednesday into Thursday.
Such an unprecedented storm could not only bring heavy snowfall to non-paved areas, but also downed trees and power outages. Most roads will be wet, but there can be slushy and slippery spots.
Forecast Challenge: In order for it to snow and accumulate, let alone bring this sort of snowfall away from the higher elevations in May, conditions have to be perfect with just the right balance of warm, moist air and cold, dry air. Typically in this situation, a very narrow band or a small area of heavy snow falls, rather than a broad leaf of snow that is often observed during the middle of winter. Most often, the snow this time of year last only a few hours, changes to rain or melts as it falls. In May, accumulating snow must also overcome a warm ground, sun effect and marginal temperatures. It must snow hard for a small accumulation to occur away from the High Plains and Rockies, especially in the area of eastern Nebraska, neighboring Kansas, Iowa, southeastern Minnesota and the lower part of northwestern Wisconsin. In order for there to be a foot of snow, it must snow extremely hard for a long period of time. The position of this band of intense snow is critical. A shift in the estimated track of the anticipated heavy band by 50 to 100 miles would mean the difference between a heavy accumulation, snow melting as it falls and heavy rain.
As a result, there is a much greater chance of error with a May snowstorm as opposed to a similar storm during the middle of the winter. Odds favor much less snowfall, on the order of a few inches in a narrow band.
The arrival of fresh cold air on the scene will lay the groundwork for an unprecedented May snowstorm. |
The accumulation of snow would vary tremendously in a local area from hilltops to shallow valleys, as well as from road surfaces to grassy areas to tree tops. The snow is more likely to melt on most warm road surfaces but could cling to tree limbs. Cars would have to be cleaned off. Patches of roads and sidewalks that don't receive direct sunlight on a clear day might be more receptive to the snow in this situation.
May Snowstorms: A Historical Perspective There have been some snowstorms in May in the region, but they are rare. 1907 sticks out as a benchmark year for a number of locations. However, multiple years during the mid-1940s also brought snow events to the region for several years in a row. According to National Weather Service records for May, there have never been more than 2.0 inches of snow in Omaha, Neb. On May 9, 1945, 2.0 inches of snow fell. There have been two snowfalls on May 3 over the years in Omaha. One was 1.3 inches in 1907 and another was 1.0 inch in 1967. The heaviest May snowfall on record for Des Moines, Iowa, was during 1907, when 1.2 inches fell on the third day of the month. There has been measurable (0.1 of an inch or more) snow as late at May 15, which was set the same year.
So it seems the odds are greatly stacked against a heavy snowfall for areas this far south with this storm.
Farther north, the odds increase for more substantial snow. About 100 miles north of Des Moines, along I-35, in Mason City, Iowa, there has been 4.0 inches of snow as late as May 28 in the year 1947. That storm continued into the next day and brought a grand total of 4.5 inches. Meanwhile, the Minneapolis-St. Paul area has received measurable snow as late as May 15, during 1907. On May 11, 1946, a storm brought 2.8 inches of snow. Records for the area date back into the late 1800s. In Eau Claire, Wis., records only date back to 1949. The only measurable snowfall during May since then was 0.7 of an inch on the ninth day of the month in 1960.
Get Ready for a Snowstorm: While the storm is likely to bring accumulating snow, a swath of 6 to 12 inches of snow would be unprecedented this late in the season from Omaha to Minneapolis and vicinity.
Given the weather pattern of recent weeks and months, such a snowfall is a strong possibility in this case. Despite a recent warm surge, cold air has been lingering in southern Canada and is again dropping southward, ready to dive into the storm. At the very least, while the storm will bring another dose of needed moisture to some areas on the Plains, it will also add to planting delays and flooding problems in areas that have received an overabundant amount of moisture in recent weeks. Stretches of I-29, I-35, I-80 and I-90 could be adversely affected by this storm. Delays are possible on these highways and others. Flight delays could occur at airports in the region due to deicing operations. - AccuWeather.
(2/5) Yesterday was the coldest May day in Hong Kong in almost a century, with temperatures plunging to 16.6 degrees Celsius in the morning.
ReplyDeleteThis was the lowest temperature recorded in May since 1917.
There are many snowstorms which happen on the world.
ReplyDeletethank for sharing~!
ReplyDelete