unstable air

unstable air

unstable airclick for a larger image
A mass of air whose temperature lapse rate is greater than that of the air surrounding it. If this mass of air is forced upward for any reason, it will continue to move upward. Its speed will increase as it moves up, because the environmental lapse rate is higher than the dry lapse rate.
References in classic literature ?
The eye detects no joint in her skin plating save the sweeping hair-crack of the bow-rudder--Magniac's rudder that assured us the dominion of the unstable air and left its inventor penniless and half-blind.
With an unstable air mass affecting the area, clouds are likely to develop by afternoon on Tuesday and showers and isolated thunderstorms are expected mainly in the mountains, but also inland and possibly on the south and east coasts.
Met Office meteorologist Greg Dewhurst told PA the ingredients needed for a tornado are unstable air through stormy conditions and 'wind shear'.
With mostly moderate northwest winds, a cold front is passing through the country that will cause unstable air mass.
They can be caused by a combination of unstable air, solar heating, orographic lifting and an atmospheric trigger that lifts moist air parcels into areas of instability, amplifying buoyancy and propelling a building cumulus cloud to ever greater heights.
Hailstorms happen when there is a formation of cumulonimbus clouds due to unstable air mass in the atmosphere, according to the PDRRMC.
However, it is not a perfect predictor of thunderstorms since they not only require unstable air but also moisture and a lifting mechanism.
At the same time, unstable air is creating a strong rising motion, sending plumes of black smoke and heat sky-high.
The Met Office said the atrocious weather was a result of a fast-moving and active "unstable air mass".
Although the risk of flooding is believed to be low, the Met Office's chief forecaster said: "A front coming from the Atlantic will merge with warm, unstable air over the country to bring the risk of 30-40mm in the hour in places and more than 50mm in a few hours."