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:

24 AUG 2019

Temp/Wind data from:

NOAA Digital Forecast
Sat Sun Mon Tue Wed Thu
Site
Name
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Torrey Pines Gliderport W 8 0 W 8 0 W 9 0 SW 7 0 W 7 0 W 7 0
Blossom Valley W 12 2855 W 12 3495 W 14 2582 W 6 2458 W 6 2458 W 6 2855
Horse Canyon SE 6 8210 NW 12 8210 W 14 8210 W 9 8560 W 10 8210 W 10 8385
Little Black W 10 674 W 10 695 W 12 674 W 8 674 W 8 653 W 9 674
Marshall SW 10 3722 SW 12 4003 SW 12 3722 SW 6 7074 SW 8 4003 SW 7 4003
Crestline S 12 1832 SW 13 1832 SW 13 1609 SW 10 2376 SW 13 2089 SW 12 1832
Mentone W 12 5914 W 12 5914 W 12 4241 SW 7 8198 SW 8 5914 W 8 4805
Kagel S 15 2991 W 14 3431 S 9 2601 SW 10 3431 S 15 2991 SW 15 2991
Lake Elsinore W 10 8625 W 14 8625 W 14 5535 SW 10 8958 SW 12 8625 W 13 8289
Laguna E 9 2283 E 9 6489 E 10 5731 SW 14 7384 SW 17 7204 W 14 6489
Big Black W 9 3459 W 10 3744 W 12 2967 W 10 3459 W 12 3188 W 12 3459
Otay Mesa W 10 1181 W 10 1772 W 12 760 W 9 930 W 9 930 W 10 930
Soboba SW 13 4285 SW 12 4502 SW 14 3463 SW 9 4719 SW 10 4285 SW 10 4502
Henninger Flats S 8 2643 W 13 3506 S 7 2643 S 8 3288 S 10 3068 SW 10 3288
Palomar W 8 1224 W 9 1413 W 10 931 SW 8 931 SW 8 931 W 8 1224
Thomas Mt NW 8 7933 NW 12 8110 NW 13 8110 SW 9 8701 W 10 9369 W 10 8288
Winchester SW 15 5388 SW 14 5388 S 17 4933 SW 12 5943 SW 12 5388 SW 10 5388
Blackhawk SW 15 6956 NW 12 7314 W 10 7135 W 12 8027 SW 13 8027 SW 13 7493
Ord SW 17 8434 S 17 8434 S 20 8258 SW 14 8961 SW 17 8610 SW 16 8434
Warner Springs SW 10 9153 SW 12 9822 SW 13 9489 SW 9 10297 SW 10 9822 SW 10 9822

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