Detailed Predictions for: Tollhouse
Launch Lat, Long, Altitude (f): 37.011555, -119.37, 4000
LZ Altitude (f): 1900
Sounding

Station:

KOAK

Date/Time:

16 SEP 2021

Temp/Wind data from:

NOAA Digital Forecast

Site Forecasts
Time
(Local)
High
Temp

Puddle
Temp

Wind
(mph)
Wind
Gust
Thermal
Ceiling

(ft)
Soaring
Ceiling

(ft)
Above
Launch

(ft)
Thermal
Type
Thermal
Index

(F)
12 Midnight Thu 68 63 NE 6 14 3625 4000 0 Blue 0
1 AM Thu 67 62 NE 6 14 3625 4000 0 Blue 0
2 AM Thu 67 62 NE 6 14 3625 4000 0 Blue 0
3 AM Thu 66 61 NE 6 12 3625 4000 0 Blue 0
4 AM Thu 65 60 NE 5 12 3625 4000 0 Blue 0
5 AM Thu 64 59 NE 5 12 3625 4000 0 Blue 0
6 AM Thu 64 59 NE 5 12 3625 4000 0 Blue 0
7 AM Thu 64 59 NE 5 11 3625 4000 0 Blue 0
8 AM Thu 71 66 NE 2 3 3625 4000 0 Blue 0
9 AM Thu 77 73 SW 2 3 4350 4000 0 Blue 0
10 AM Thu 79 77 SW 5 6 8568 4719 719 Blue 3
11 AM Thu 82 82 SW 6 7 9783 8690 4690 Blue 8
12 Noon Thu 85 86 SW 7 8 11510 10361 6361 Blue 12
1 PM Thu 87 88 SW 7 8 12460 10903 6903 Blue 14
2 PM Thu 88 89 WSW 7 8 12919 11391 7391 Blue 15
3 PM Thu 88 88 WSW 8 9 12460 10903 6903 Blue 14
4 PM Thu 88 86 WSW 7 8 11510 10361 6361 Blue 12
5 PM Thu 86 82 WSW 6 7 9783 8690 4690 Blue 8
6 PM Thu 84 79 WSW 6 7 8704 5695 1695 Blue 5
7 PM Thu 73 68 NW 1 3 3625 4000 0 Blue 0
8 PM Thu 68 63 NE 7 15 3625 4000 0 Blue 0
9 PM Thu 66 61 NE 7 15 3625 4000 0 Blue 0
10 PM Thu 65 60 NE 7 15 3625 4000 0 Blue 0
11 PM Thu 65 60 NE 7 15 3625 4000 0 Blue 0
12 Midnight Fri 66 61 NE 6 14 3625 4000 0 Blue 0
1 AM Fri 65 60 NE 6 13 3625 4000 0 Blue 0
2 AM Fri 64 59 NE 6 12 3625 4000 0 Blue 0
3 AM Fri 64 59 NE 6 12 3625 4000 0 Blue 0
4 AM Fri 63 58 NE 6 12 3625 4000 0 Blue 0
5 AM Fri 63 58 ENE 6 12 3625 4000 0 Blue 0
6 AM Fri 62 57 NE 5 11 3625 4000 0 Blue 0
7 AM Fri 62 57 NE 5 11 3625 4000 0 Blue 0
8 AM Fri 69 64 NE 2 3 3625 4000 0 Blue 0
9 AM Fri 76 72 SW 2 2 4072 4000 0 Blue 0
10 AM Fri 78 76 SW 5 5 5707 4346 346 Blue 2
11 AM Fri 82 82 SW 6 7 9783 8690 4690 Blue 8
12 Noon Fri 84 85 SW 7 8 11016 9671 5671 Blue 11
1 PM Fri 86 87 SW 7 8 11991 10534 6534 Blue 13
2 PM Fri 87 88 SW 7 8 12460 10903 6903 Blue 14
3 PM Fri 87 87 SW 7 8 11991 10534 6534 Blue 13
4 PM Fri 87 85 SW 7 8 11016 9671 5671 Blue 11
5 PM Fri 85 81 WSW 6 7 9165 8622 4622 Blue 7
6 PM Fri 82 77 SW 5 8 8568 4719 719 Blue 3
7 PM Fri 72 67 NNW 1 2 3625 4000 0 Blue 0
8 PM Fri 68 63 NE 7 15 3625 4000 0 Blue 0
9 PM Fri 67 62 NE 7 16 3625 4000 0 Blue 0
10 PM Fri 66 61 NE 6 14 3625 4000 0 Blue 0
11 PM Fri 66 61 ENE 6 12 3625 4000 0 Blue 0
12 Midnight Sat 66 61 ENE 6 12 3625 4000 0 Blue 0
1 AM Sat 65 60 ENE 5 11 3625 4000 0 Blue 0
2 AM Sat 63 58 ENE 4 10 3625 4000 0 Blue 0
3 AM Sat 63 58 NE 4 9 3625 4000 0 Blue 0
4 AM Sat 62 57 NE 4 10 3625 4000 0 Blue 0
5 AM Sat 62 57 NE 4 10 3625 4000 0 Blue 0
6 AM Sat 61 56 NE 4 9 3625 4000 0 Blue 0
7 AM Sat 61 56 NE 5 10 3625 4000 0 Blue 0
8 AM Sat 69 64 NE 2 3 3625 4000 0 Blue 0
9 AM Sat 75 71 SW 3 3 3792 4000 0 Blue 0
10 AM Sat 75 73 SW 6 7 4350 4000 0 Blue 0
11 AM Sat 79 79 SW 6 7 8704 5695 1695 Blue 5
12 Noon Sat 81 82 SW 6 7 9783 8690 4690 Blue 8
1 PM Sat 83 84 SW 7 8 10571 9061 5061 Blue 10
2 PM Sat 83 84 SW 8 9 10571 9061 5061 Blue 10
3 PM Sat 83 83 WSW 8 9 10397 8782 4782 Blue 9
4 PM Sat 83 81 WSW 7 8 9165 8622 4622 Blue 7
5 PM Sat 81 77 WSW 7 8 8568 4719 719 Blue 3
6 PM Sat 79 74 WSW 5 8 4755 4000 0 Blue 0
7 PM Sat 70 65 NNW 2 5 3625 4000 0 Blue 0
8 PM Sat 66 61 NE 6 14 3625 4000 0 Blue 0
9 PM Sat 65 60 NE 6 14 3625 4000 0 Blue 0
10 PM Sat 64 59 NE 7 15 3625 4000 0 Blue 0
11 PM Sat 63 58 NE 6 14 3625 4000 0 Blue 0

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 ac_soaring@yahoo.com