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:

18 SEP 2019

Temp/Wind data from:

NOAA Digital Forecast
error getting data for coordinate: 33.329,-116.97225
Wed Thu Fri Sat Sun Mon
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 8 0 W 8 0 W 7 140 SW 7 140 SW 10 0
Blossom Valley W 8 2740 W 9 1891 W 8 3243 W 7 3794 SW 9 3692 SW 10 2487
Horse Canyon W 14 2709 W 17 938 E 10 3217 E 12 4195 SW 13 4654 SW 18 2709
Little Black W 9 1132 W 12 594 W 9 1132 W 8 1834 W 9 1834 SW 10 660
Marshall SW 9 1193 S 8 526 N 17 2500 N 9 4029 SW 12 4513 SW 9 983
Crestline S 14 0 S 14 0 N 18 272 NE 13 1513 SW 16 2040 S 15 0
Mentone W 9 2143 W 9 1593 SW 6 2774 NE 6 4282 SW 9 5675 S 8 1818
Kagel S 12 1594 SW 9 786 NE 20 1907 SW 8 4039 S 14 4039 SW 13 1489
Lake Elsinore SW 14 2890 SW 15 2301 NW 13 3632 W 13 6130 SW 15 6130 SW 15 2640
Laguna SW 24 2749 SW 30 622 E 15 1178 E 16 2240 SW 16 3419 SW 31 0
Big Black SW 13 1392 W 16 283 W 10 1497 SE 8 3472 SW 13 3472 SW 16 1181
Otay Mesa W 10 1979 W 12 1484 W 10 1841 W 9 2688 W 9 2939 SW 12 1979
Soboba SW 12 2108 SW 13 1195 W 6 2615 E 7 3196 S 13 3792 SW 12 1596
Henninger Flats SW 9 1903 SW 8 1387 NE 7 2007 SW 7 4565 SW 10 3570 S 8 1591
Thomas Mt W 14 4122 W 17 2278 NE 12 3281 E 9 5796 W 13 6073 W 16 3500
Winchester SW 12 3204 S 14 1779 W 8 3307 S 9 4251 S 13 4774 SW 13 2800
Blackhawk SW 13 3374 SW 17 2200 N 10 631 E 10 3035 SW 23 5313 SW 23 1169
Ord S 20 3173 SW 16 811 NE 12 2137 NE 8 4090 SW 21 5422 S 20 1597
Warner Springs SW 13 5123 W 15 3454 SE 8 6125 E 8 6921 SW 12 7134 SW 14 3732

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