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:

30 APR 2016

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 SW 12 0 SW 12 0 W 10 0 W 10 0 W 10 0 W 14 0
Blossom Valley SW 12 3185 SW 10 3501 W 12 4382 W 10 5498 W 12 4724 W 15 3501
Horse Canyon SW 14 373 W 9 2130 NW 8 5586 W 10 6852 W 14 6362 SW 17 3020
Little Black SW 12 0 SW 12 2125 W 12 3612 W 10 3871 W 12 3612 W 14 2338
Marshall SW 8 894 SW 12 1597 SW 14 5993 SW 13 7169 SW 17 6206 SW 20 2298
Crestline NW 9 0 SW 13 506 SW 14 4948 SW 13 6835 SW 18 5539 SW 21 1476
Mentone W 13 1757 SW 7 2595 W 14 6718 SW 12 9133 SW 16 7601 SW 18 3566
Kagel N 10 2263 S 12 2263 SW 13 4334 SW 14 6897 S 14 4334 SW 14 1481
Lake Elsinore W 16 2239 SW 13 3222 W 14 7472 W 14 8709 SW 14 7678 SW 15 3571
Laguna W 31 0 N 10 2661 SE 9 5202 W 8 7342 SW 14 7342 SW 22 3251
Big Black SW 13 862 SW 10 1648 W 10 2813 W 12 5951 W 13 4874 SW 17 1648
Otay Mesa SW 12 2392 W 12 3346 W 12 4190 W 9 4960 W 12 4548 W 13 3376
Soboba SW 12 2464 SW 10 2975 SW 13 4527 W 13 7807 SW 15 6684 SW 17 3558
Henninger Flats NW 14 1957 SW 8 2487 SW 10 5935 SW 12 7499 S 13 4825 S 13 1728
Palomar SW 9 782 W 9 1645 W 9 2002 W 10 2949 W 12 2596 SW 15 1614
Thomas Mt W 17 0 N 12 2175 SE 6 6259 W 7 9234 SW 14 8449 SW 20 4853
Winchester SW 14 2909 SW 13 3187 SW 15 4781 W 14 7674 SW 15 5559 SW 16 3187
Blackhawk NW 24 293 N 8 3790 E 8 5612 SW 6 9755 SW 18 8621 SW 21 4789
Ord NW 17 1809 S 16 4147 SW 14 6063 SW 13 8649 SW 23 8189 SW 24 4717

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