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:

25 MAY 2019

Temp/Wind data from:

NOAA Digital Forecast
error getting data for coordinate: 32.7747,-116.477 error getting data for coordinate: 33.5999,-116.65385
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 W 8 0 SW 12 0 W 12 0 W 10 0 SW 9 0 W 9 0
Blossom Valley W 9 2318 SW 12 0 W 12 1786 W 10 2683 W 8 4677 W 10 4202
Little Black W 10 0 SW 12 0 W 13 0 W 12 1673 W 9 2490 W 10 2354
Marshall SW 12 1738 S 14 0 SW 10 0 SW 10 4294 SW 10 5133 SW 12 5133
Crestline SW 16 0 S 20 0 SW 14 0 SW 13 2028 N 13 3109 SW 14 2895
Mentone W 12 4286 S 10 0 W 10 575 W 10 5319 W 9 6187 W 12 6731
Kagel S 14 1541 S 15 0 SW 12 351 SW 14 4108 SW 13 4978 SW 10 4875
Lake Elsinore SW 16 4614 SW 16 0 W 16 992 W 13 5925 W 14 8292 W 16 7134
Laguna SW 18 3209 SW 39 0 W 35 0 NW 16 4282 NW 12 7191 NW 12 7681
Big Black W 10 989 SW 16 0 W 13 0 W 9 4068 W 8 4691 W 10 4922
Otay Mesa W 10 1875 SW 12 0 W 14 1738 W 12 2207 W 10 3786 W 12 3223
Soboba SW 13 2471 SW 14 0 S 9 0 SW 10 3270 SW 10 6441 W 9 6441
Henninger Flats SW 8 3194 S 10 0 S 9 458 SW 16 4727 SW 9 5208 SW 6 4974
Palomar W 8 402 SW 10 0 W 10 0 W 9 866 W 8 2275 W 9 2275
Winchester SW 14 3000 SW 13 0 SW 9 1187 SW 13 5970 S 13 7113 SW 12 6872
Blackhawk SW 17 5555 SW 37 1069 W 26 2212 W 17 6670 SW 12 8128 W 9 10017
Ord S 23 5357 S 30 0 S 23 910 SW 13 6194 S 17 7027 SW 16 7027
Warner Springs SW 12 6425 W 13 761 W 15 1767 W 10 7202 SW 10 9017 SW 12 9428

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