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:

21 JUL 2018

Temp/Wind data from:

NOAA Digital Forecast
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 10 0 NW 10 0 W 8 0 W 8 0 SW 8 140 SW 10 140
Blossom Valley W 12 2646 W 10 3795 W 10 5027 W 12 7814 W 13 8125 W 13 6639
Horse Canyon NW 12 4324 NW 12 8206 NW 10 9229 W 12 9637 W 13 9229 W 12 8616
Little Black W 12 1306 W 10 1425 W 9 1906 W 10 2732 W 10 3227 SW 12 2526
Marshall SW 12 2186 SW 9 5227 N 12 7525 N 18 9450 N 13 8840 SW 13 7525
Crestline SW 13 0 SW 10 764 N 15 5106 N 17 6797 N 16 5895 SW 14 4567
Mentone W 10 2603 W 9 5310 W 10 8032 W 13 9686 W 12 9686 W 12 8324
Kagel S 10 1665 S 10 5481 SW 10 8014 SW 14 8301 SW 14 9840 SW 13 9637
Lake Elsinore W 13 3650 W 13 8464 W 14 10837 W 15 11442 W 15 11241 SW 15 10431
Laguna SW 10 3291 W 9 8548 W 13 9384 W 15 10003 W 16 10003 W 16 8966
Big Black W 10 1407 W 9 5982 W 10 7264 W 12 9100 W 12 9100 W 12 8689
Otay Mesa W 13 1646 NW 13 2595 W 10 2914 W 12 3559 W 12 4723 W 12 3559
Soboba SW 10 3248 W 12 6333 W 9 8596 W 13 10238 SW 12 9520 SW 13 8596
Henninger Flats S 8 2010 SW 8 5079 SW 8 7760 SW 8 8052 SW 9 8765 SW 10 8337
Palomar W 8 481 W 8 2242 W 8 3003 W 9 5741 W 10 6670 W 10 4544
Thomas Mt W 13 5176 W 14 8500 W 12 9126 W 13 9946 W 13 9946 W 13 9126
Winchester SW 13 4262 NW 10 7405 SW 10 9378 SW 12 10423 SW 13 9662 SW 15 9378
Blackhawk N 7 5614 W 9 8487 W 9 9319 W 13 9934 SW 16 10341 SW 16 9524
Ord S 22 4737 S 15 8168 SW 13 9408 S 17 9819 S 18 10024 S 21 9201
Warner Springs SW 12 7049 W 9 9887 SW 10 11311 SW 13 12123 SW 14 11514 SW 14 10698

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