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:

19 NOV 2017

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 NW 7 0 W 6 0 NW 5 184 NW 6 328 NW 7 280 SW 5 224
Blossom Valley W 7 1964 W 8 1964 W 7 4735 E 8 6549 E 7 5423 W 8 4594
Horse Canyon NE 7 1851 W 7 2283 NE 17 4345 NE 15 6066 NE 10 6066 W 8 4626
Little Black W 8 0 W 8 0 W 8 1002 W 6 4511 W 8 3748 W 7 1002
Marshall N 15 1883 NE 6 1883 N 20 2583 N 16 3789 N 13 4458 S 6 2444
Crestline N 13 0 NE 5 869 N 18 1187 N 16 2240 NE 13 2832 S 7 1187
Mentone S 3 1415 SW 5 1662 SW 5 3915 NE 7 4976 NE 6 5260 NE 5 3420
Kagel NE 13 148 NE 14 1133 N 14 2518 NE 9 2649 NE 9 2649 S 7 2454
Lake Elsinore NW 7 3313 NW 6 3442 NW 9 5440 N 7 6004 N 6 6283 SW 7 4926
Laguna NE 5 510 NW 3 1308 NE 10 1308 E 10 3063 E 6 4088 W 8 3643
Big Black NE 6 2057 W 7 2122 E 15 4199 E 17 5334 E 9 5334 W 8 3686
Otay Mesa NW 9 514 W 8 514 NW 8 4481 E 7 5364 W 9 4871 E 8 4165
Soboba E 7 2194 W 6 2194 NE 16 4108 E 12 4386 E 8 4386 SW 7 3865
Henninger Flats N 7 1454 W 9 1454 N 6 2747 N 6 3175 NE 6 3037 SW 6 2683
Palomar W 7 0 W 7 0 E 6 2789 E 13 3409 E 8 3273 W 7 2789
Thomas Mt NE 6 594 W 8 2045 NE 14 2966 NE 12 4743 NE 8 5856 W 8 4164
Winchester NW 6 2062 W 5 2635 NE 5 4528 S 2 4659 E 2 5463 SW 8 4351
Blackhawk W 5 0 NW 10 1424 E 7 2767 E 5 4154 NE 5 4731 SW 12 4154
Ord N 5 16 NW 9 1482 NE 10 2280 NE 6 3382 NE 3 3382 SW 9 3382
Warner Springs E 3 4191 W 5 4370 E 12 6813 E 12 7371 E 10 7371 SW 8 6247

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