NEWS:

June 29, 2009: This site is running the code developed by Tad Hurst.

I've done some tuning to make the estimates for Marshall, Crestline and Soboba a bit less optimistic. 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


Site Forecasts

Sounding

Station:

KNKX (alt)

Date/Time:

12Z 30 AUG 2015

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
Torrey Pines Gliderport W 12 0 SW 12 0 W 9 0 W 10 0 W 12 0 W 12 0
Blossom Valley W 14 3000 SW 12 730 W 9 181 W 12 107 W 12 181 W 13 523
Horse Canyon W 14 7312 SW 10 4984 SW 8 2894 W 10 2894 SW 12 4984 SW 13 4885
Little Black W 13 362 SW 12 115 W 9 0 W 10 0 W 10 66 SW 10 66
Marshall SW 12 5257 SW 10 2198 S 8 0 S 10 0 S 13 0 S 13 0
Crestline SW 14 4123 S 13 1737 S 12 0 S 13 0 S 14 0 S 14 0
Mentone W 10 3936 SW 9 3013 SW 7 0 SW 9 0 SW 12 0 SW 12 796
Kagel S 12 2484 S 12 599 S 10 0 SW 12 0 SW 12 0 SW 10 0
Lake Elsinore W 18 7972 SW 14 4046 SW 12 2173 W 13 1723 W 12 2747 W 10 3291
Laguna W 23 6560 SW 20 6560 SW 21 6335 SW 20 5096 SW 18 5893 SW 17 5096
Big Black W 14 2448 SW 10 414 SW 8 0 SW 9 0 SW 12 0 W 13 0
Otay Mesa W 13 677 W 10 131 W 9 0 W 10 0 W 10 0 W 12 57
Soboba SW 14 3783 SW 12 997 S 9 0 SW 12 0 SW 13 25 W 14 25
Henninger Flats S 12 2780 S 10 1094 S 9 0 S 10 0 SW 10 0 SW 9 0
Palomar W 9 0 SW 8 0 W 7 0 W 8 0 W 10 0 W 12 0
Thomas Mt W 16 7787 W 10 7520 W 10 5409 W 12 5409 W 14 3932 SW 14 5409
Winchester SW 15 5081 SW 13 3372 S 12 913 SW 13 913 SW 13 1129 SW 14 1601
Blackhawk SW 18 7554 SW 14 8017 S 18 6955 SW 14 6955 SW 14 3184 W 12 5744
Ord S 23 8340 S 23 8780 S 24 7214 S 23 7214 SW 23 4701 SW 21 6034

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