NEWS:

March 24, 2013: This site is running the code developed by Tad Hurst.

This section created with the help of Aaron Colby.
Why not submit your favorite site? I need site name, lat, long, LZ and launch altitudes and the zipcode.

- Alan

See the southern California RASP Model The detail grid covers the San Diego sites, but the 4km grid covers most of southern California.

Instructional video on reading the RASP Model

NEW!
Check out the WINDGRAMS Windgrams are available for some Eastern Sierra sites from the more accurate RASP data


Sounding

Station:

KVBG (alt)

Date/Time:

16 JUL 2019

Temp/Wind data from:

NOAA Digital Forecast
Tue Wed Thu Fri Sat Sun
Site
Name
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Garlock SW 23 6886 SW 23 6542 SW 24 6542 SW 22 3839 SW 20 6225 S 16 6542
Boomer Ridge W 36 7429 SW 28 6318 SW 26 6318 SW 30 4904 SW 26 5792 S 25 5966
9-Mile W 29 9258 SW 24 8430 SW 24 8430 SW 24 6272 SW 20 7378 S 18 7912
Flynns NW 10 10497 S 14 10086 SE 16 9895 S 14 9895 SE 12 8670 S 16 9085
Gunter SW 13 6587 SW 14 6447 S 14 6167 S 13 6727 SE 12 6447 S 13 6587
Paiute SW 14 8154 W 16 8012 S 14 7726 S 14 8012 S 10 7869 S 12 8012
Chalk Bluffs NW 9 11480 SE 10 10894 S 10 10894 S 12 10894 S 7 10090 S 14 10496
McGee Creek SW 12 7322 W 13 7322 SW 9 7035 S 8 7035 E 8 7035 SE 9 6748
Bria Dog Ridge W 15 7692 W 15 7550 S 13 7266 SE 12 7692 E 12 7266 SE 12 7408
Mammoth SW 23 2969 W 15 4861 SW 13 4326 SW 10 4326 NE 9 3444 SW 12 3444
Walts S 16 7038 SE 20 6616 SE 21 6757 SE 21 5848 SE 17 5848 SE 21 5848
Copper Mountain W 13 5541 W 15 6408 W 12 5541 W 12 6764 N 9 5089 SE 10 5979
Horseshoe S 16 7038 SE 20 6616 SE 21 6757 SE 21 5848 SE 17 5848 SE 21 5848
Wolf Peak SW 14 5595 SW 14 6024 SW 12 5595 SW 12 4711 NE 10 4189 W 9 4711
Sweetwater SW 18 5512 W 16 6525 W 14 6237 S 12 5944 NE 12 4622 N 10 5512
Lake Isabella Ground Launch Center W 22 4395 W 16 4395 SW 17 5520 SW 17 1558 SW 17 2961 S 15 5520

DISCLAIMER: These estimates are intended to assist in daily site selection only.  No warranty is made concerning the accuracy of these estimates.  These estimates cannot be used to determine if conditions are safe for flying.  Conditions should be evaluated at the launch site by experienced pilots before launching.

Sounding: This is the site at which the weather balloon was released.  If the flying site predicted is far from the sounding site, the estimate is not valid.  Also, the sounding is done at 12Z (4AM PST).  If a front comes through, the sounding is no longer valid. The sounding becomes less valid later in the day.

Thermal Ceiling: the lower of the height at which the thermal stops rising and the cloud level.  We can't fly into the clouds, so it doesn't matter how much higher the thermal goes.  Remember that we can't get to the top of the thermal because of our sink rate.  Our upper limit will be lower than the reported ceiling.

Soaring Ceiling: We will stop going up when the thermal is rising just fast enough to offset our sink.  It is estimated that this happens when the temperature difference between the thermal and the surrounding air is about 2 degrees F. This number is an estimate of the maximum altitude we might reach if we start at launch height, and should be more reflective of our chances of soaring than the thermal top. Please let me know how this compares with actually flying, and I will adjust it as necessary.

Above Launch: The difference between how high we might get and how high we start. This estimate does not account for ridge lift.

High Temp: This estimate is taken from the National Weather Service website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the National Weather Service estimate of cloudiness, and the angle of the sun.  When the sun is directly overhead on a sunny day, the puddle temp is esimated to be 25 degrees warmer than the high ambient temperature. This estimate now includes a rigorous calculation of the Sun Angle, and accounts for the seasonal differences in zenith and daylight hours.

Wind: This estimate is taken from the National Weather Service website.

Thermal Type: Blue (no cloud formation) or White (Cloud formation)

Thermal Index: This is the maximum difference in temperature between the rising packet of air (the thermal) and the surrounding air.  The difference in temperature is responsible for the buoyancy of the thermal, and larger temperature differences mean faster rising thermals.  A value of about 10 F or greater often means that the conditions are soarable.  Values above 20 could indicate rowdy thermals.

Validity of estimate: Many factors (including strong wind, fronts, cloud shadows, incorrectly predicted temperatures, etc) can affect the validity of the estimates. 

Author: Tad Hurst

Supported By: Alan Crouse ac_soaring@yahoo.com