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:

25 AUG 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
Torrey Pines Gliderport W 8 0 W 8 0 W 9 0 W 8 0 W 7 0 W 7 0
Blossom Valley W 12 2940 W 12 2763 W 12 1731 W 6 1731 W 5 2940 W 6 2940
Horse Canyon W 10 7249 NW 12 7249 W 12 9310 W 10 9310 W 10 9821 W 12 10439
Little Black W 10 441 W 12 344 W 12 292 W 8 344 W 9 392 W 8 441
Marshall SW 12 4931 SW 12 3648 SW 13 4931 SW 8 4931 SW 7 4931 SW 7 5873
Crestline SW 13 1472 SW 13 1472 SW 14 2108 SW 13 1930 SW 13 2108 SW 13 2108
Mentone W 12 5559 W 12 4440 W 13 7579 SW 8 5559 SW 8 5559 SW 8 7579
Kagel S 9 3545 S 9 1724 SW 14 3545 S 13 1724 SW 14 2021 SW 8 2021
Lake Elsinore SW 14 8400 W 14 6864 SW 12 8400 SW 12 6864 W 12 8400 W 13 8400
Laguna E 12 3877 E 10 5392 E 12 6040 W 16 6679 W 16 6254 W 18 6254
Big Black W 12 2928 W 10 2928 W 9 2928 SW 10 3454 W 12 3454 W 13 4655
Otay Mesa W 9 658 W 12 658 W 10 595 W 9 658 W 10 914 W 10 914
Soboba SW 13 3351 SW 13 2766 SW 14 4386 SW 10 3077 W 10 4386 W 10 4386
Henninger Flats SW 9 2128 S 7 1539 SW 14 2128 S 10 1831 SW 10 2128 SW 8 3092
Palomar W 9 1128 W 8 222 W 9 363 SW 9 363 W 8 1128 W 9 1560
Thomas Mt NW 10 6999 NW 10 7421 NW 13 7837 SW 10 8045 SW 10 7837 W 12 8045
Winchester SW 15 5283 S 16 4854 SW 16 5456 SW 12 4854 W 10 5456 W 10 5456
Blackhawk NE 9 6762 NE 9 6762 NE 14 7603 SW 14 7812 SW 13 7394 SW 13 7812
Ord S 17 9657 S 17 9444 S 23 10068 SW 17 9863 SW 15 9657 SW 14 9863
Warner Springs SW 10 8016 SW 10 9197 SW 13 9651 SW 10 9197 W 10 10214 W 10 10214

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