Mike, add special emphasis to the reading of the Z-scale numbers.
The NOAA radar depiction sets their lowest color level (cyan)
at -24 to -28 dBZ when no storms are shown on the presentation,
but when storms are present, the same color is +5 to +10 dBZ.
That's why a casual look at the radar can mislead the unwary
to mistake wet clouds for a rainstorm. The dBZ numbers rule.
---JRC---

"Mike Rapoport" wrote in message =
news
Weather Radar is the same as vision in another part of the spectrum. =
It has=20
certain resolution and can penetrate a certain distance into obscuring =

conditions. The beam reflects off all surfaces (except the stuff =
stealth=20
aircraft are made of presumably). The value of radar is that there is =
a=20
very high corralation between the reflectivity of water droplets and=20
turbulence. Large droplets are formed from vertical motion.and large=20
droplets reflect radar much better than small ones (that is why most =
clouds=20
appear transparent to radar.). More vertical motion larger drops. =
You have=20
undoubtedly experienced the difference in drop sizes from =
thunderstorms vs.=20
stratiform rain. To evaluate a target, you first have to determine =
that you=20
are not looking at a ground return which you do by knowing your =
altitude,=20
beam width and antenna tilt setting. Generally you avoid all radar =
targets=20
containing red (40dbz) returns. You avoid the whole target, not just =
the=20
red part. I usually avoid yellow too. Even green targets are fairly =
bumpy=20
and full of ice at cruise altitudes (above FL180). Green at lower =
altiudes=20
can be smooth. There are various shapes that are associated with hail =
and=20
tornados but most people avoid all thunderstorms. The irregular =
targets are=20
just avoided by a greater distance.
=20
Basically it comes down to the fact that anything that lifts huge =
amounts of=20
water miles into the atmosphere contains a lot of vertical shear and=20
therefore turbulence.
=20
There are several books on the subject, I like Archie Trammels stuff, =
Dave=20
Gwinn's book and Severe Weather Flying by Newton. There was a great =
deal on=20
AvWeb a couple of years ago where you got Trammels video course, =
Severe=20
Weather Flying and Buck's Weather Flying for around $125 along with a=20
discount for his live course.
=20
Mike
MU-2
=20
=20
"Matt Young" wrote in message=20
ink.net...
A question about something that I guess I just didn't get enough info =
on=20
during my instrument training. What exactly are you looking for when=20
looking at a radar image. Are you trying to avoid all returns? Is an =
area=20
of just green ok? Any other things in particular to look for?=20
=20