NEWS:

March 24, 2013: This site is running the code developed by Tad Hurst.

This section created with the help of Aaron Colby.
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 Windgrams are available for some Eastern Sierra sites from the more accurate RASP data


Sounding

Station:

KVBG (alt)

Date/Time:

15 OCT 2018

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
Garlock NE 26 3793 N 21 4364 NE 10 4364 NW 7 5000 NE 14 5115 NE 15 5057
Boomer Ridge N 30 3208 N 22 3493 N 12 3493 E 10 4039 NE 15 4214 NE 17 4098
9-Mile N 33 3606 N 29 4171 N 14 4229 NW 7 5808 N 10 8026 N 15 5808
Flynns N 8 3648 N 7 4251 N 5 4134 NW 5 5336 NE 6 5336 E 7 4695
Gunter N 10 262 NE 9 321 NE 8 262 NE 7 381 NE 9 720 E 9 441
Paiute N 17 1820 SE 10 1880 NE 9 1880 NW 8 2491 N 8 3801 N 9 2491
Chalk Bluffs NW 5 5138 NW 6 5365 NW 6 5423 NE 5 6052 NE 6 8711 E 6 5785
McGee Creek NE 15 973 NE 9 973 NE 7 912 NE 7 4574 NE 8 5682 E 9 5682
Bria Dog Ridge NE 14 1309 NE 10 1309 NE 9 1429 N 8 1550 NE 9 1749 E 10 3286
Mammoth NE 29 0 NE 15 0 NE 9 0 N 9 0 NE 10 2678 NE 13 2678
Walts NW 29 749 NW 24 868 NW 12 1074 W 8 4622 NW 12 5344 NW 15 4622
Copper Mountain NE 12 881 NE 10 881 NE 8 1479 NE 8 1063 NE 8 1133 E 9 1133
Horseshoe NW 29 749 NW 24 868 NW 12 1074 W 8 4622 NW 12 5344 NW 15 4622
Wolf Peak E 16 525 NE 13 464 NE 9 740 NE 8 1027 NE 8 1027 E 8 3976
Sweetwater E 16 266 NE 13 266 NE 9 661 NE 9 2119 NE 10 3692 E 14 3692
Lake Isabella Ground Launch Center E 18 4106 SE 14 4246 N 8 4246 SW 6 4859 NE 9 4859 NE 14 4916

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  If a front comes through, the sounding is no longer valid.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

Supported By: Alan Crouse ac_soaring@yahoo.com