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 2018

Temp/Wind data from:

NOAA Digital Forecast
Tue Wed Thu Fri Sat Sun
Site
Name
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Torrey Pines Gliderport W 13 0 W 12 0 W 9 0 SW 10 140 W 10 140 W 12 140
Blossom Valley W 12 1705 W 12 1443 W 12 1443 W 13 1705 W 13 2225 W 13 2483
Horse Canyon W 12 3249 W 10 2720 E 16 2720 W 8 2897 W 10 3249 W 12 3249
Little Black W 13 269 W 12 237 W 12 301 W 13 301 W 13 336 W 14 336
Marshall SW 10 1559 SW 9 1559 SW 14 2933 SW 13 1917 SW 13 2432 SW 13 2933
Crestline S 13 0 S 10 0 SW 14 0 SW 13 0 S 13 0 SW 14 0
Mentone W 10 2136 W 10 1898 W 15 2663 W 12 2136 W 13 2373 W 14 2663
Kagel S 16 1058 SW 8 2072 NE 9 3666 S 15 3451 SW 13 2953 SW 13 2443
Lake Elsinore SW 14 3078 W 9 2843 SW 16 4467 SW 14 3586 W 14 4642 W 15 4467
Laguna SW 20 3935 SW 17 3935 E 15 2499 E 8 2838 E 8 4209 W 13 3935
Big Black W 10 1590 W 12 1351 E 16 2345 W 10 1590 W 10 2345 W 13 2856
Otay Mesa W 13 684 W 13 628 W 12 684 W 13 684 W 14 855 W 15 1130
Soboba SW 15 3133 W 10 2899 SW 13 3133 SW 14 3133 SW 13 3746 W 15 3366
Henninger Flats S 12 2145 SW 8 872 S 7 1910 S 12 1675 SW 12 1404 SW 10 1133
Palomar W 9 620 W 9 0 W 8 620 W 10 98 W 10 620 W 10 879
Thomas Mt W 13 4636 W 13 4636 E 12 4101 W 9 4369 W 12 4636 W 14 5572
Winchester SW 16 4210 SW 9 3801 S 17 4709 SW 16 3801 SW 14 4709 W 10 5196
Blackhawk SW 18 6250 SW 13 4850 E 15 3889 NE 12 4850 NE 9 5761 NE 8 5761
Ord S 22 2563 SW 14 2563 S 13 3097 S 16 2741 SW 16 2919 SW 17 3097
Warner Springs SW 13 5747 SW 10 5572 E 16 5572 SW 12 5572 SW 12 5961 W 13 6289

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