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 JUL 2014

Temp/Wind data from:

NOAA Digital Forecast
Mon Tue Wed Thu Fri Sat
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 W 10 0 W 8 0 W 9 0 W 9 0 W 9 0
Blossom Valley W 13 2616 W 14 3391 W 10 2151 W 12 2616 W 12 2616 W 12 2616
Horse Canyon W 12 6989 NW 13 7826 NW 12 7625 NW 13 8030 NW 12 7826 W 13 7826
Little Black W 12 582 W 13 634 W 9 530 W 10 634 W 10 582 W 10 582
Marshall SW 10 4701 SW 9 8796 SW 9 9002 SW 10 9618 SW 10 9618 SW 12 9413
Crestline SW 12 6579 SW 10 7410 S 10 7617 SW 10 8031 SW 10 8031 SW 10 7824
Mentone W 10 4414 W 10 5352 W 8 7028 W 12 9732 W 10 9732 W 12 8901
Kagel S 13 3143 SW 8 6093 SW 12 6858 N 12 8768 SW 13 6858 SW 10 8768
Lake Elsinore W 18 4288 W 17 5329 W 18 5775 W 20 7368 W 15 6576 W 15 6576
Laguna W 16 6331 W 18 8593 W 18 8801 W 16 9217 NW 14 9009 W 14 8801
Big Black W 13 1301 W 13 3024 W 12 3024 W 13 4081 W 12 4081 W 13 3024
Otay Mesa W 12 670 NW 13 1607 W 10 1085 W 10 1212 W 12 1085 W 10 1212
Soboba SW 13 5459 W 13 6461 W 12 7313 W 15 8067 W 13 8067 W 15 7313
Henninger Flats S 8 1949 SW 7 4669 SW 10 4669 SW 10 5109 SW 13 5109 S 10 5109
Palomar W 10 161 W 10 1055 W 9 1055 W 9 1733 W 10 1733 W 12 1547
Thomas Mt NW 14 3829 NW 15 7196 W 14 8467 NW 15 8884 W 14 8676 NW 15 8467
Winchester SW 16 4386 SW 12 5424 SW 12 5920 SW 13 6967 W 10 6967 W 13 6382

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