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 17 APR 2014

Temp/Wind data from:

NOAA Digital Forecast
Thu Fri Sat Sun Mon Tue
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 SW 15 0
Blossom Valley W 12 1613 W 13 1311 W 12 1530 W 9 2302 W 12 2302 W 18 1258
Horse Canyon E 12 1510 SW 13 0 SW 8 1093 E 14 3868 W 14 3868 W 25 0
Little Black W 12 1357 W 13 1244 W 10 1410 W 9 1653 W 12 1679 SW 15 841
Marshall S 12 1458 S 13 0 SW 9 461 SW 12 2274 SW 15 2274 S 21 0
Crestline S 13 0 S 15 0 SW 8 0 N 13 0 S 16 0 S 22 0
Mentone SW 10 2282 SW 10 120 W 9 1062 SW 12 2638 SW 14 2638 SW 20 0
Kagel SW 13 301 SW 13 0 SW 9 583 W 8 1767 SW 15 1561 W 17 0
Lake Elsinore SW 13 1394 SW 12 372 W 9 1155 W 10 2553 SW 9 2326 SW 17 289
Laguna E 13 4135 SW 15 0 NE 8 1914 E 15 4789 W 14 4789 W 33 0
Big Black S 9 135 SW 13 0 W 9 0 SE 13 494 W 13 494 W 23 0
Otay Mesa W 12 1235 W 13 1156 W 12 1208 W 10 1563 W 12 1730 SW 16 1104
Soboba SW 10 2824 SW 13 809 W 9 1702 SE 10 2824 W 16 3027 W 21 809
Henninger Flats SW 9 657 SW 10 0 SW 8 657 SW 8 2383 SW 12 2029 SW 17 0
Palomar W 9 0 W 10 0 W 10 0 W 9 557 SW 12 389 SW 18 0
Thomas Mt SE 14 2297 W 13 0 NW 8 3 E 13 4004 W 16 2297 W 28 0
Winchester SW 14 2680 SW 13 1063 SW 10 1997 W 10 3250 W 14 2917 SW 18 1063

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  If a front comes through, the sounding is no longer valid.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