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 AUG 2014

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 SW 9 0 SW 10 0 W 8 0 W 7 0 W 8 0 W 8 0
Blossom Valley W 12 1859 W 10 1453 W 9 1258 SW 7 1258 W 9 1453 W 10 1355
Horse Canyon W 9 4822 SW 8 4446 W 9 3741 W 9 3741 W 10 3741 W 10 1314
Little Black W 9 536 W 9 502 W 8 491 W 7 491 W 8 480 W 8 491
Marshall SW 8 4845 S 8 4845 SW 9 2790 SW 10 528 SW 12 840 SW 10 1561
Crestline SW 10 4921 S 9 4921 S 12 3793 S 12 630 SW 12 3083 SW 12 3083
Mentone W 8 3324 SW 7 3324 SW 8 1515 SW 9 1203 SW 10 1203 SW 10 1203
Kagel SW 12 1185 SW 12 563 S 13 0 SW 12 0 SW 12 0 SW 10 874
Lake Elsinore W 14 2154 SW 12 1843 SW 10 802 SW 8 698 W 10 802 W 10 906
Laguna SW 18 4584 SW 13 4206 SW 15 3822 SW 18 3433 SW 12 3433 SW 12 3068
Big Black W 10 583 SW 9 269 SW 8 0 W 8 0 W 10 0 W 10 0
Otay Mesa W 9 753 W 9 611 W 8 153 W 7 334 W 9 468 W 9 334
Soboba SW 12 3359 SW 9 2473 SW 10 1858 W 12 1254 W 14 1858 W 14 2012
Henninger Flats SW 12 805 S 9 59 S 12 0 SW 9 59 SW 9 59 SW 9 960
Palomar W 8 96 SW 8 0 SW 8 0 SW 7 0 W 9 0 W 10 0
Thomas Mt W 13 3395 W 8 3395 W 9 2651 W 9 847 W 13 847 W 12 847
Winchester SW 13 2592 SW 10 2439 SW 10 1367 SW 10 1367 W 13 1470 W 13 1573

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  If a front comes through, the sounding is no longer valid.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