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:

21 JUL 2019

Temp/Wind data from:

NOAA Digital Forecast
Sun Mon Tue Wed Thu Fri
Site
Name
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Garlock S 21 9450 SW 16 8465 S 16 5090 W 15 7256 SW 18 7256 W 18 9450
Boomer Ridge W 20 11014 SW 23 9483 SW 24 8403 W 22 8403 W 29 9483 W 28 9996
9-Mile SW 24 12741 SW 23 9940 SW 25 10444 SW 22 10444 W 25 11896 W 25 12096
Flynns S 14 14233 S 15 12620 SW 14 11987 SW 13 11987 SW 13 11987 W 14 11987
Gunter S 17 12518 S 16 11507 S 13 8406 SW 12 8406 SW 12 9054 SW 13 8733
Paiute S 20 14948 S 20 13153 S 14 9950 S 12 9950 SW 13 9950 SW 14 10301
Chalk Bluffs S 12 13624 S 13 13065 S 10 11753 S 9 11200 SW 10 11753 W 10 11200
McGee Creek SW 14 13828 SW 15 9770 SW 13 9441 W 12 9441 W 12 9770 W 13 9770
Bria Dog Ridge S 18 13873 SW 17 10146 SW 16 9818 SW 12 9175 S 10 9818 W 15 9818
Mammoth SW 15 8805 SW 16 6288 SW 15 4038 S 13 4038 SW 13 4607 W 13 4038
Walts S 24 9743 S 23 7143 S 23 8499 SE 20 7143 S 21 8201 S 21 8706
Copper Mountain SW 17 10875 SW 17 9287 SW 16 6161 W 12 6161 W 12 6718 W 15 5582
Horseshoe S 24 9743 S 23 7143 S 23 8499 SE 20 7143 S 21 8201 S 21 8706
Wolf Peak SW 17 9788 SW 18 8875 SW 17 8194 SW 14 8194 W 14 7470 W 13 7470
Sweetwater SW 20 11713 SW 21 9148 SW 18 8155 W 14 8155 W 14 8155 S 13 7941
Lake Isabella Ground Launch Center W 20 7578 SW 16 4525 SW 17 4525 SW 14 3840 SW 17 5095 W 18 6245

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