On June 11th, 2013, in the wee hours of an early summer night in Nebraska, the temperature shot from 73°F to 99°F in the space of minutes
, accompanied by 50MPH winds. The cause of this weather oddity was the poorly understood Heat Burst
, a phenomenon that sometimes occurs as thunderstorms die out
, usually late at night. The temprature rise can be so extreme that it has been imaged from space
, and there are unconfirmed stories
of heat so extreme that crops were cooked in the fields where they grew, and paint blistered on houses and vehicles. Once believed to be a very rare
event, with the advent of personal weather stations, science may find they are more frequent than was previously believed.
posted by smoothvirus
on Jun 12, 2013 -
California's calm before the storm.
It's just rain, right? Well, the meteorologists are publicly talking about a potentially epic
storm that could trigger major flooding and mudslides
, especially in areas effected by the state's widespread fires of the past few years. More ominously, though, is this internal email from CAL FIRE Division Chief Bob Wallen
, which talks of the potential for "multiple large and powerful storm systems" with "a tremendous amount of precipitation . . . Much of NorCal is likely to see 5-10 inches in the lowlands, with 10-20 inches in orographically-favored areas. Most of SoCal will see 3-6 inches at lower elevations, with perhaps triple that amount in favored areas", with the potential for a massive snowfall, gusts in the 100-200 mph range in the high Sierras, possibly followed by plentiful warm rains that could melt the snow and cause massive flooding statewide. "The next 2-3 weeks (at least) are likely to be more active across California than any other 2-3 week period in recent memory."
posted by markkraft
on Jan 16, 2010 -
Forecast calls for cold and warm.
On January 22, 1943 in Spearfish, SD: The temperature rose 49 degrees in two minutes, from – 4 to 45; later the same morning, it dropped 60 degrees in 27 minutes, from 56° to - 4°. Plate glass windows cracked as a result of the wild fluctuation in temperatures caused by Chinook winds. The greatest 24- hour U.S. temperature difference in one place was set January 23- 24, 1916, in Browning, MT, at 100 degrees when it went from a low of -56° to a high of 44°.*
is one way it's been described, old tales too.
. It's a seasonal wind, like the Mistral.
There is some overlap in the definitions but the Chinook can safely be labeled a Foehn wind. A Foehn wind is "a generic term for warm strong and often very dry downslope wind(s) that descend in the lee of a mountain barrier". That is the one illustrated above. My favorite wind though, is the katabatic. A downhill wind. Cold and dense
it blows here on Earth
especially in the Antarctic
, and there on Mars
too. (page 9 of 14.) [more inside]
posted by vapidave
on Dec 5, 2009 -