On Aug 26, 4:58*pm, Alex wrote:
On Aug 26, 3:04*pm, Ramy wrote:









On Aug 26, 8:35*am, WaltWX wrote:

Ramy,

I agree with your assessment. My focus for the good weather is aimed
at the Owens Valley, and Mojave Deserts (south of Bridgeport). *More
moisture spreading over entire area on Saturday with cloud bases
15,000-16,000 north of Bishop instead of 17,000msl. Widely scattered
TS in the usual hot spots but the cells should be fairly small and
short lived. *Sunday, as Alex pointed out below, looks a little drier
everywhere... still at least a very good to outstanding day.

Walt, Wx

On Aug 25, 11:51*pm, Ramy wrote:

On Aug 25, 5:45*pm, WaltWX wrote:

Take a look Dr Jack...

Outstanding soaring weather Fri through Sun. *Lift rates 700-800fpm
average... much stronger in those 10 per cent...

It's a toss up between Fri and Sunday. *The Mojave Desert, Owens
Valley and Western NV show full cu coverage bases 15,500 to 17,500. It
appears to be dry enough that only isolated thunderstorms will form in
the normal "hot spots". *Early trigger times also.

I reviewed Dr Jack this afternoon with a long ago crew of mine, John
Halcrow. *For Crystalaire, the pattern on Friday looks as good as I'v ever seen it. *BL (thermal) max heights 17,500msl (of course cloud
bases will limit altitudes to a little lower).

I'm coming back out Saturday to give my 750 km triangle another try
from Inyokern (please... leave me room for an 11:30am takeoff

Walt Rogers, WX

I don't see the same outstanding conditions when reviewing the NAM
blipmap, especially for going north towards Minden. Bases only 15-16K,
lots of moisture with potential for overcast and OD and stronger wind
to the north. Could still be good but probably not as good as it was
the last few days.

Ramy- Hide quoted text -

- Show quoted text -

One little known secret of Dr Jack Blipmap is the "Total Cloud Cover"
parameter. This is one of the most reliable parameters I've seen to
detect overcast. If there are white areas you are pretty much
guarantee that there will be at least some level of overcast. It does
not tell if it will be high cirrus or mid level overcast, and how
thick it will be, nor if it will be persistent or short lived. But it
hardly ever fails to detect that there will be some degree of overcast
in the area. It indicated *successfully today pockets of overcast
especially in the southern zones of region 11 and 12, and more so
tomorrow over the central Sierra. None for Sunday.

For those who prefer looking at the RASP, besides the Avenal one,
there is one which covers the whole Sierra:http://www.norcalsoaring.org/BLIP/SIERRA/index.html
It has 'BL Cloud Cover' but I did not use it enough to confirm if it
provides the same as the NAM Total Cloud Cover.

Ramy

Also on the Dr. Jack RASP sites, if the operator has set up locations
for plotting forecast
soundings as *Skew-T diagrams, *you can see on the left side of these
diagrams
black lines corresponding to forecast cloud layers. *These *try to
forecast both the heights and thicknesses *of cloud layers. * *These
include *cloud layers that
are above the "boundary layer" that most of the blipmap diagrams
concern themselves with, *such as high cirrus layers. * *If there is
also a similar layer marked in green over on the left side
representing *"cloud water in g/k", that seems to correspond with the
chance of
precipitation. * An example of this could be seen today on some of the
soundings from the Avenal RASP, such as this one:

http://alcald.homelinux.org//RASP/AV...8.curr.1400lst...

Alex Caldwell

Rapid Refresh plots have this and more and are a lot more accurate
than RUC or NAM based Blipmaps. It'll be nice when RR goes online and
replaces RUC.

Mike