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:

12Z 28 MAY 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 W 9 0 W 8 0 SW 9 0 SW 12 0 SW 10 0 W 8 0
Blossom Valley W 9 2020 W 10 2140 W 10 2082 SW 10 1698 SW 10 2020 W 10 2140
Horse Canyon W 9 7316 W 8 7316 W 9 7176 W 12 1674 W 10 2920 E 10 4589
Little Black W 10 1373 W 9 1458 W 10 1373 SW 13 1205 W 12 1542 W 10 1744
Marshall SW 10 4214 SW 10 4809 SW 13 4214 SW 13 398 SW 12 2013 SW 13 3667
Crestline N 10 3892 SW 12 4622 SW 14 3892 SW 15 0 SW 14 549 SW 14 2227
Mentone W 9 3607 W 9 4440 W 10 4440 W 10 849 W 10 2371 W 12 4019
Kagel S 10 3775 S 13 4747 SW 14 3358 SW 12 132 SW 10 731 SW 12 2134
Lake Elsinore W 10 6541 W 9 6541 SW 10 4866 SW 14 1526 W 14 3226 W 15 4866
Laguna E 9 7265 E 9 8108 E 10 7265 SW 17 2386 E 8 3700 E 12 6005
Big Black W 8 3235 W 7 2822 W 7 2412 SW 9 0 W 10 461 W 9 1996
Otay Mesa W 12 1694 W 10 1694 W 10 1647 SW 12 1507 SW 12 1694 W 12 1843
Soboba SW 10 6495 SW 12 5910 SW 12 5399 SW 13 1410 SW 12 2539 SW 9 4183
Henninger Flats SW 9 2542 SW 9 2949 SW 12 982 SW 8 0 SW 8 169 SW 8 982
Palomar W 7 644 W 7 644 W 8 401 SW 9 0 W 10 153 W 8 401
Thomas Mt E 10 8536 W 10 9470 SE 9 8536 W 13 3123 W 13 5138 NW 12 6814
Winchester SW 13 5023 SW 14 4627 SW 13 4226 S 14 1767 S 13 2431 SW 12 4226
Blackhawk E 13 7996 E 12 11758 E 12 13358 SW 15 5064 NE 9 6716 NE 9 8602
Ord S 14 8912 S 18 8912 S 21 8504 S 23 3931 S 15 5964 S 18 7643

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