Peter Duniho wrote:
*"R. Hubbell" wrote in message
news:Badyb.12188$ZE1.9049@fed1read04...
Why would you want a tow to where lenticulars clouds have formed?

Two words: mountain wave. *


Formation of the mountain waves relies on several conditions. The
atmosphere is usually stable and an inversion may exist. The wind needs
to be blowing almost constantly within 30 degrees of perpendicular to
the barrier at a minimum speed of about 20 to 25 knots at the
ridgeline. Wind speed needs to also increase uniformly with height and
remain in the same direction. Wave crests can be upwind or downwind
from the range and their amplitude seems to vary with the vertical
stability of the flow. The crests of the waves may, (depending on the
air having sufficient moisture content), be identified by the formation
of lenticular clouds. Mountain waves can even extend into the
stratosphere and become more pronounced as height increases. I remember
reading somewhere of U2 pilots reportedly experiencing mountain waves
at 60,000 feet!!. In Australia, mountain waves are commonly experienced
over and to the lee of mountain ranges in the southeast of the
continent. They also often appear in the strong westerly wind flows our
east coast experiences in late winter and early spring. We definately
had some this year in mid-August for periods of up to 3 &4 5 days at a
time!
MQD_117.3


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mqd_117.3
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