On Mar 27, 9:27 am, "gatt" wrote:
"Sushidot" wrote in message

...

High Pressure Systems The weather is warm here and the visibility is good,
atmosphere is stable. This makes me think of summer weather. The book
says that
visibility in terms of clouds is not good...am i missing something here...

Haze, smog and temperature inversions. Think of a smokey room. The warm,
stable air causes the smoke to just hang there and the room gets stale, but
turning on a fan will mix things up. Another way to think of it is that
rain washes away haze which is why the air is so clear right after a
thunderstorm has passed. So if you go flying on a nice summer afternoon, a
few thousand feet up you're likely to climb above a haze layer that is
difficult to see through.

Low Pressure Systems The weather is cold here, visibility is poor and the
atmosphere is
less stable. This makes me think of winter weather.

Visibility is poor if the air is saturated, but for a memory aid you can
recall the most extreme-cold below-zero days, when the sky is sunny and the
air is crystal clear. Or, recall looking out the window of a jet at cruise
altitude. Low pressure and unlimited visibility, but sometimes it's
turbulent.

If it makes you feel any better, this stuff is hard to remember because as a
private pilot, unless you're flying cross-country a lot you don't get much
exposure to it and the knowledge is lost due to lack of recency. The main
thing he'll want to know on the checkride is that you're able to identify
bad or deteriorating weather--thunderstorms, lenticular clouds and their
implications. I'd be pretty surprised if he asked you much beyond what's
covered in the written in terms of charts and symbols and if he does, as
long as you have a reference source for planning he probably won't abuse you
too much for the PPL. He's going to focus more on your flying. For
example, if you're flying cross-country in the northern hemisphere and you
pick up an increasing wind from the left, it means you're probably flying
toward low pressure (hurricanes spin counterclockwise and all you have to do
to remember that is recall how Katrina pushed the water in from the Lake
Ponchartrain as the storm passed to the east.)

By knowing the direction that the weather system is rotating, for flight
planning purposes you can determine which side of the system you want to fly
in order to use the tailwind to your advantage. For your flight planning,
as long as you have the basic idea and a good reference source such as the
AVIATION WEATHER book by the FAA/NTSB, you'll probably do just fine.

-c

Thank You !