NEWS:

Feb 16, 2021
- Problems getting data from National Weather Service began on Feb 11 impacting operation of the Soaring Predictor software.
The service seems to be working again at about 75% as of this morning, Feb 16.


Backup data is being sourced from WeatherAPI.com however, their free service is limited to 3 days. If you see a three day forecast for your favorite site, thank the WeatherAPI folks. The full 5-day forecasts are receiving input data from the National Weather service (thank them too :-).

Sounding

Station:

KOAK (alt)

Date/Time:

19 JUN 2024

Temp/Wind data from:

NOAA Digital Forecast
Wed Thu Fri Sat Sun Mon
Site
Name
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Wind Above
Launch
Dumps W 12 0 W 11 0 WSW 9 0 W 10 0 WSW 12 0 WSW 11 0
Mt Diablo WSW 10 8599 W 9 12532 W 9 15632
Ed Levin W 10 1705 W 10 4610 WNW 10 7707 WNW 10 12190 W 10 9215 W 9 7177
Mission Peak W 11 481 W 10 1857 WNW 10 5638 WNW 10 8573 W 10 6829 W 10 5186
Potato Hill ESE 6 6307 S 6 10173 SW 8 13560 SSW 13 14639 SSW 12 13560 SSW 10 12250
Mt Tamalpais W 9 0 W 9 0 WSW 8 110 WSW 8 599 WSW 9 0 WSW 9 0
Tollhouse WSW 6 7219 WSW 6 9183 WSW 6 12869 SW 5 16023 SW 6 15759 SW 6 14595
Elk Mountain W 8 6335 W 8 9221 WSW 6 14796 SSW 8 15958 SSW 6 14543 SW 6 13184
Big Sur W 6 0 WNW 5 0 WNW 3 2010 N 2 4333 W 2 438 W 4 0
Ft Funston W 13 0 W 11 0 W 10 0 W 10 0 WSW 11 0 WSW 11 0
Marina Beach W 11 0 WNW 11 0 WNW 9 0 W 8 0 WNW 9 0 WNW 9 0
Dunlap SW 5 4967 W 6 6238 W 5 10410 WSW 5 13920 WSW 6 13920 WSW 5 12467
Weaver Bally WNW 9 6614 W 14 8218 W 11 11883 W 12 13321 W 12 11620 W 12 10812
Timberline S 10 5436 SW 11 7434 WSW 10 13671 SSW 12 14285 WSW 11 13189 WSW 10 12587
Burn Launch SW 5 8555 W 5 10765 NNE 5 13996 SW 11 14683 SW 13 13996 SW 12 13421
Hat Creek Rim WNW 10 11529 WNW 8 12351 WNW 8 15760 WSW 13 16342 WSW 13 15760 WSW 12 15299
St John SE 9 1570 WSW 9 3177 SSW 10 9099 SW 19 10205 SSW 17 8359 SSW 13 7515
Noel Springs ESE 8 4838 SW 8 8913 NW 9 13016 S 17 13703 S 13 13016 SSE 11 11621
Lake McClure W 8 7614 WNW 8 9978 W 6 10778 WSW 6 12542 SW 8 12154 SW 6 11571
Sugar Hill ESE 6 9398 NW 5 10325 WNW 5 12938 WSW 13 14534 WSW 13 13758 WSW 12 13194
Goat Mountain W 9 10506 NW 6 12083 NNW 6 14644 SW 8 16802 SW 9 16568 WSW 8 15823
Mt Vaca WSW 12 4564 WSW 11 4819 SW 10 10070 SW 10 12327 SW 11 9147 SW 11 6243
Hull Mountain S 10 7368 W 12 8914 WSW 12 14376 SSW 14 15068 WSW 14 14376 WSW 12 13328

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 or WeatherAPI.com website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the National Weather Service or WeatherAPI.com 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 or WeatherAPI.com website.

Wind Gust: This estimate is taken from the National Weather Service or WeatherAPI.com 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 [email protected]