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 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 :-).



KTUS (alt)


27 SEP 2021

Temp/Wind data from:

NOAA Digital Forecast
Mon Tue Wed Thu Fri Sat
Wind Above
Wind Above
Wind Above
Wind Above
Wind Above
Wind Above
South Mountain E 4 8082 WSW 14 9100 S 7 8694
Oatman Mt NE 9 10123 SW 19 11021 SSE 8 9419
Shaw Butte WSW 5 8485 WSW 13 9503 SSE 5 8892
The Y SW 8 7129 SSW 16 7758 SSE 12 6918
Phoenix Regional SE 4 6614 SSW 6 9370 SSE 6 6614 E 8 3299 ENE 6 8083 E 8 9370
Humbolt NNE 5 7797 SW 10 8418 S 7 8211
Miller Canyon WSW 13 4716 WSW 11 4935 S 9 4935 SE 6 3564 E 11 3838 E 11 4935
Box Canyon W 13 7670 WSW 12 8289 W 10 8494
Mustang Mountain WSW 13 6068 WSW 13 6068 WSW 11 6068 E 8 4791 E 14 5217 ESE 14 6068
Whetstone Mountain WSW 13 5208 WSW 13 5424 WSW 11 5424 E 9 3866 E 14 4304 ESE 16 5424
Mt Lemmon W 9 8422 SW 9 8422 WSW 9 8835
A Mountain W 9 6640 SW 10 7474 SW 8 7265 N 9 5392 E 11 6850 ESE 11 7717
Rainbow Valley NW 4 6805 WSW 14 9922 SSW 6 9309
Pinal Peak SW 10 0 WSW 12 2942 WSW 11 2942 ENE 9 0 E 12 1391 E 11 3584
Harquahala SSW 8 4658 S 16 4873 SSE 11 159 E 10 159 ESE 10 4658 ESE 10 5083
El Tiro Gliderport W 9 5397 SW 11 8399 SSE 8 7947 NE 9 3394 ESE 9 5956 ESE 8 8399
Mt Ord NNE 5 7326 SW 10 7947 S 7 7740

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  If a front comes through, the sounding is no longer valid.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 website.  Puddle temperatures can exceed this temperature. 

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

Wind Gust: This estimate is taken from the National Weather Service or 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