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 31 OCT 2014

Temp/Wind data from:

NOAA Digital Forecast
Fri Sat Sun Mon Tue Wed
Site
Name
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Torrey Pines Gliderport W 12 0 W 18 0 E 8 0 NW 10 0 N 9 0 NE 8 0
Blossom Valley W 13 2124 W 16 0 W 8 0 N 10 2156 NE 10 2699 NE 13 4061
Horse Canyon SW 13 1463 SW 22 0 W 10 0 NE 10 121 NE 15 2281 NE 16 3001
Little Black W 12 0 W 15 0 E 9 0 NW 10 0 NE 9 307 NE 10 2368
Marshall S 14 1356 S 17 0 N 7 0 N 15 343 NE 15 2260 NE 13 3679
Crestline S 16 0 S 21 0 N 13 0 N 16 0 NE 16 807 NE 15 2359
Mentone SW 9 1178 S 13 0 NW 7 418 NE 14 771 NE 14 2096 NE 13 3940
Kagel SW 15 315 SW 15 0 N 20 190 NE 17 709 NE 23 2143 NE 17 3504
Lake Elsinore SW 14 1400 SW 21 0 W 12 1031 N 10 1533 NE 10 3405 NE 12 4722
Laguna SW 21 1598 SW 45 0 W 21 0 NE 10 0 NE 15 1366 NE 17 2440
Big Black SW 13 0 SW 22 0 W 8 0 NE 9 0 NE 12 562 NE 16 2162
Otay Mesa W 13 1505 W 15 0 E 8 0 NW 10 1505 NE 10 2172 E 12 2934
Soboba SW 15 1741 S 15 0 SW 9 1282 NE 10 1489 NE 12 2357 E 13 3682
Henninger Flats SW 13 298 SW 14 0 N 14 408 NE 13 941 NE 10 2453 NE 8 3837
Palomar SW 12 403 SW 13 0 W 8 0 NE 10 371 NE 10 662 NE 13 1652
Thomas Mt SW 13 1058 W 30 0 NW 14 0 NE 13 0 NE 13 457 NE 14 1887
Winchester S 15 1857 SW 15 0 W 8 286 NE 9 1825 NE 12 2298 E 13 3628

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  If a front comes through, the sounding is no longer valid.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