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:

15 JUL 2024

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
Dumps WSW 10 0 WSW 10 0 W 10 0 W 11 0 WNW 11 0 W 11 0
Mt Diablo WSW 12 653 WSW 12 157 WSW 11 454 WSW 10 1561 W 10 2844 WSW 10 2737
Ed Levin W 9 922 W 9 779 WNW 9 779 WNW 9 1536 WNW 9 1705 W 8 1705
Mission Peak W 10 627 W 10 151 W 9 466 W 9 939 W 9 1439 W 9 1233
Potato Hill ESE 9 5936 SSE 11 2510 SSW 8 2403 WSW 10 4474 WSW 9 13115 SW 9 13115
Mt Tamalpais W 6 0 WSW 6 0 W 9 0 W 10 93 W 10 146 W 9 66
Tollhouse SSW 5 6512 WSW 6 6512 WSW 6 4691 WSW 6 6512 WSW 5 12042 WSW 5 12448
Elk Mountain SSW 8 12820 S 8 4899 WSW 6 3717 W 8 8101 W 6 12820 W 6 13008
Big Sur W 2 0 W 3 0 WNW 3 0 NW 3 0 WNW 4 0 WNW 4 0
Ft Funston WSW 10 0 WSW 10 0 W 11 0 W 12 0 W 12 0 W 11 0
Marina Beach W 8 0 W 8 0 WNW 11 0 WNW 10 0 WNW 11 0 WNW 10 0
Dunlap SW 5 1457 WSW 6 1350 WSW 6 564 WSW 6 1350 WSW 5 2763 WSW 5 4904
Weaver Bally SSE 9 7580 SE 16 6958 WSW 10 2752 W 12 5375 W 11 6958 W 9 8404
Timberline SSW 10 8993 S 12 3767 SW 8 2738 W 10 8582 W 10 8787 SW 8 9608
Burn Launch W 6 10864 SW 13 10660 SW 9 10251 WSW 8 10660 WSW 6 11475 SSW 6 12085
Hat Creek Rim WSW 9 11838 WSW 11 11635 W 11 11635 W 10 12037 W 10 12831 WSW 10 13425
St John S 11 14305 S 12 13528 WSW 8 13917
Noel Springs SSE 10 4620 SE 11 861 SE 6 861 W 10 2663 W 9 7504 S 9 9632
Lake McClure W 8 5056 W 8 3773 W 8 3478 W 8 5056 WNW 8 6939 W 6 10040
Sugar Hill W 5 9360 WSW 17 9562 W 9 9562 W 8 9562 SW 6 10167 SSW 6 11176
Goat Mountain WSW 6 11495 SSW 6 11294 WNW 6 11093 NW 8 11495 NW 8 11896 WNW 6 12496
Mt Vaca WSW 11 901 SW 11 456 WSW 9 901 SW 9 2875 SW 9 4445 SW 9 4445
Hull Mountain S 10 10307 SSE 13 9260 WSW 10 6629 W 12 9890 W 11 10098 WSW 10 10724

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]