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:

4 AUG 2015

Temp/Wind data from:

NOAA Digital Forecast
Tue Wed Thu Fri Sat Sun
Site
Name
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Torrey Pines Gliderport NW 10 0 W 12 0 W 10 0 W 10 0 W 12 0 W 9 0
Blossom Valley W 12 1695 W 13 3351 W 12 2105 W 13 1143 W 13 932 W 12 1695
Horse Canyon W 10 6987 W 10 8206 W 9 4542 W 12 2175 W 12 1364 W 12 4542
Little Black W 10 760 W 12 869 W 12 760 W 12 645 W 12 584 W 9 869
Marshall SW 9 3248 SW 9 2137 SW 10 931 SW 13 275 SW 12 275 SW 12 1737
Crestline S 10 1853 S 10 1853 S 12 275 SW 14 0 SW 13 0 SW 13 2261
Mentone W 9 4594 W 9 2912 W 10 2912 W 13 1006 W 12 1006 W 12 2107
Kagel SW 10 895 SW 10 1452 SW 10 895 SW 15 520 SW 12 187 SW 12 671
Lake Elsinore W 10 6498 W 10 6498 SW 15 2191 W 13 2191 W 12 1619 W 10 2948
Laguna SW 14 6560 SW 16 6925 SW 17 4002 SW 18 1469 W 17 289 W 15 4002
Big Black W 12 929 W 12 3242 W 9 473 W 12 0 W 13 0 W 12 30
Otay Mesa W 13 882 W 13 1347 W 12 882 W 13 718 W 10 680 W 10 756
Soboba SW 13 2468 SW 14 3966 SW 13 2081 SW 15 1393 SW 16 1079 W 16 1841
Henninger Flats SW 10 1535 SW 10 1928 SW 10 1234 SW 14 394 SW 12 295 SW 10 776
Palomar W 7 0 W 8 867 W 8 0 W 9 0 W 10 0 W 9 0
Thomas Mt W 13 7226 NW 14 6869 W 10 5605 W 15 3102 W 15 2108 W 14 6869
Winchester SW 15 4411 SW 15 4411 S 16 2502 SW 16 1906 SW 16 1720 SW 15 2391
Blackhawk SW 13 8383 SW 20 9913 SW 15 7887 SW 16 4175 SW 15 3444 W 15 7074
Ord S 21 7800 S 21 8153 S 23 5356 S 23 2068 SW 21 2068 SW 17 5356

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