26 June 2013
Wild Weather Update
19 Tamuz 5773
Major West US Heat Wave in the Making
Temperatures will be at full throttle later this week over the interior West, reaching dangerous levels, challenging records and elevating the wildfire threat.
While many folks over the interior West are accustomed to and expect hot weather during the summer the developing pattern will take the heat to the extreme. In some cities record highs for any date throughout the year could be equaled or breached.
The weather this week will favor an expanding area of sunshine and building heat over the West. As temperatures soar to record-challenging levels, dry fuel and the potential for spotty dry thunderstorms will push the wildfire threat to new areas and raise the risk in other locations.
Storms, floods threaten vast swath of US
Flash flood and wildfire warnings were issued on Tuesday, as severe thunderstorms and torrential rainfall were again expected to hit the Midwest and Northeast.
"Once again, thunderstorms are expected to fire in parts of the northern Plains to Lower Great Lakes on Tuesday," the National Weather Service said.
"A separate area of severe weather is possible in the Northeast. Large hail and damaging winds will be the primary threats. In addition, rainfall could be heavy enough to cause flash flooding and river flooding in the Midwest and Lower Great Lakes," it added.
In Chicago, there were at least 200,000 power outages on Monday as severe weather lashed the area.
The storms forced the temporary closure of O’Hare International Airport....
Felled trees also led to traffic chaos across the city.
In Belmont, N.H., 23 scouts were hospitalized after being struck by lightning as they hid out from a storm.
Meanwhile, in Wisconsin there was almost a foot of rain over the weekend.
...Lightning strikes could also spark wildfires on the northern Plains, experts warned.
Embattled firefighters across the country have already tackled a number of huge blazes this year in Colorado, California and New Mexico.
The massive West Fork Fire in Colorado is expected to burn for some time to come.
Sunday storms add to danger, misery; 99,000 lack power
Sunday morning storms added to what already was a record number of power outages in Minnesota history and brought new flooding and road closures to some communities.
94 in Alaska? Weather extremes tied to jet stream
Lately, the jet stream isn’t playing by the rules. Scientists say that big river of air high above Earth that dictates much of the weather for the Northern Hemisphere has been unusually erratic the past few years.
They blame it for everything from snowstorms in May to the path of Superstorm Sandy.
And last week, it was responsible for downpours that led to historic floods in Alberta, Canada, as well as record-breaking heat in parts of Alaska, experts say. The town of McGrath, Alaska, hit 94. Just a few weeks earlier, the same spot was 15 degrees.
...The jet stream usually rushes rapidly from west to east in a mostly straight direction. But lately it’s been wobbling and weaving like a drunken driver, wreaking havoc as it goes. The more the jet stream undulates north and south, the more changeable and extreme the weather.
It’s a relatively new phenomenon that scientists are still trying to understand....
In May, there was upside-down weather: Early California wildfires fueled by heat contrasted with more than a foot of snow in Minnesota. Seattle was the hottest spot in the nation one day, and Maine and Edmonton, Canada, were warmer than Miami and Phoenix.
Consider these unusual occurrences over the past few years:
— The winter of 2011-12 seemed to disappear, with little snow and record warmth in March. That was followed by the winter of 2012-13 when nor'easters seemed to queue up to strike the same coastal areas repeatedly.
— Superstorm Sandy took an odd left turn in October from the Atlantic straight into New Jersey, something that happens once every 700 years or so.
— One 12-month period had a record number of tornadoes. That was followed by 12 months that set a record for lack of tornadoes.
And here is what federal weather officials call a ‘‘spring paradox’’: The U.S. had both an unusually large area of snow cover in March and April and a near-record low area of snow cover in May. The entire Northern Hemisphere had record snow coverage area in December but the third lowest snow extent for May.
‘‘I've been doing meteorology for 30 years and the jet stream the last three years has done stuff I've never seen,’’ said Jeff Masters, meteorology director at the private service Weather Underground. ‘‘The fact that the jet stream is unusual could be an indicator of something. I'm not saying we know what it is.’’
...‘‘It’s been just a crazy fall and winter and spring all along, following a very abnormal sea ice condition in the Arctic,’’ Francis said, noting that last year set a record low for summer sea ice in the Arctic. ‘‘It’s possible what we’re seeing in this unusual weather is all connected.’’
(With thanks to Global Disaster Watch.)