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 6 MAR 2015

Temp/Wind data from:

NOAA Digital Forecast
Fri Sat Sun Mon Tue Wed
Site
Name
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Torrey Pines Gliderport NE 15 224 NE 13 206 W 8 0 W 9 0 W 10 192 W 9 0
Blossom Valley E 28 4213 W 12 4984 W 10 3824 W 12 3824 W 14 3824 W 10 3421
Horse Canyon NE 36 1427 NE 25 4096 N 8 5765 NW 13 7385 NW 17 8000 SW 15 4906
Little Black E 24 1233 NE 17 1233 W 10 646 W 10 0 W 10 365 W 9 83
Marshall N 41 2595 N 36 4331 NE 13 3472 NE 10 5072 SW 10 4331 SW 10 1397
Crestline N 32 1994 N 31 4274 N 15 4274 N 13 6503 NE 12 5173 S 12 755
Mentone NE 22 3766 E 14 5753 W 10 5029 W 8 5753 W 10 5753 SW 10 2578
Kagel NE 30 4885 NE 28 5632 NE 10 7670 NE 7 8300 NE 9 8300 SW 12 3533
Lake Elsinore NE 17 6132 N 16 9071 W 12 6957 W 12 9304 W 13 7893 W 9 4660
Laguna E 33 355 E 24 2401 NE 7 4065 NE 10 8110 E 9 9883 W 17 4065
Big Black E 37 2163 E 30 3410 W 9 2962 W 12 4169 W 12 4169 W 13 2163
Otay Mesa NE 26 4168 NE 15 4168 W 12 2865 W 10 762 W 12 762 W 9 1337
Soboba NE 37 820 E 24 2382 W 8 1321 SW 8 1822 W 13 1822 W 14 820
Henninger Flats NE 20 7441 N 10 8584 W 9 8348 SW 8 9922 SW 10 8584 W 10 5534
Palomar E 31 2647 NE 17 2647 W 7 1862 W 8 2647 W 14 2257 W 10 334
Thomas Mt NE 21 3425 NE 20 9305 NE 7 11720 NE 7 12462 SE 9 11720 W 16 6781
Winchester NE 20 2861 NE 13 3307 SW 12 3307 SW 12 3307 W 14 3703 W 13 2305

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