Detailed Predictions for: Tollhouse
Launch Altitude (f): 4000
LZ Altitude (f): 1900
Sounding

Station:

 KOAK

Date/Time:

 3 SEP 2010

Temp/Wind data from:

NOAA Digital Forecast

Time
(Local)		 High
Temp
Puddle
Temp
Wind
 (mph)		 Thermal
Ceiling
(ft)		 Soaring
Ceiling
(ft)		 Above
Launch
(ft)		 Thermal
Type		 Thermal
Index
(F)
5 AM Fri 70 70 N 5 2917 4000 0 Blue 0
6 AM Fri 69 69 N 5 2917 4000 0 Blue 0
7 AM Fri 68 68 N 5 2917 4000 0 Blue 0
8 AM Fri 70 70 N 2 2917 4000 0 Blue 0
9 AM Fri 74 76 N 2 4145 4000 0 Blue 0
10 AM Fri 80 83 N 2 6488 5140 1140 Blue 6
11 AM Fri 86 91 SW 6 12062 9387 5387 Blue 14
12 Noon Fri 88 94 SW 6 14504 11820 7820 Blue 17
1 PM Fri 90 97 SW 6 15301 14254 10254 White 19
2 PM Fri 91 98 W 8 15506 14791 10791 White 20
3 PM Fri 91 96 W 8 15097 13507 9507 White 19
4 PM Fri 91 95 W 8 14894 12701 8701 White 18
5 PM Fri 90 92 W 6 12946 10045 6045 Blue 15
6 PM Fri 86 86 W 6 8058 6454 2454 Blue 9
7 PM Fri 82 82 W 6 6053 4832 832 Blue 5
8 PM Fri 78 78 N 3 4682 4000 0 Blue 1
9 PM Fri 77 77 N 3 4468 4000 0 Blue 0
10 PM Fri 76 76 N 3 4145 4000 0 Blue 0
11 PM Fri 76 76 NE 6 4145 4000 0 Blue 0
12 Midnight Sat 76 76 NE 6 4145 4000 0 Blue 0
1 AM Sat 76 76 NE 6 4145 4000 0 Blue 0
2 AM Sat 76 76 N 5 4145 4000 0 Blue 0
3 AM Sat 75 75 N 5 3820 4000 0 Blue 0
4 AM Sat 74 74 N 5 3492 4000 0 Blue 0
5 AM Sat 73 73 N 7 3161 4000 0 Blue 0
6 AM Sat 72 72 N 7 2917 4000 0 Blue 0
7 AM Sat 72 72 N 7 2917 4000 0 Blue 0
8 AM Sat 73 73 NE 3 3161 4000 0 Blue 0
9 AM Sat 77 79 NE 3 4837 4142 142 Blue 2
10 AM Sat 82 85 NE 3 7337 6024 2024 Blue 8
11 AM Sat 87 92 SW 6 12946 10045 6045 Blue 15
12 Noon Sat 89 95 SW 6 14894 12701 8701 White 18
1 PM Sat 90 97 SW 6 15301 14254 10254 White 19
2 PM Sat 91 98 W 8 15506 14791 10791 White 20
3 PM Sat 91 96 W 8 15097 13507 9507 White 19
4 PM Sat 90 94 W 8 14504 11820 7820 Blue 17
5 PM Sat 88 90 W 7 11073 8693 4693 Blue 13
6 PM Sat 84 84 W 7 6916 5586 1586 Blue 7
7 PM Sat 80 80 W 7 5158 4462 462 Blue 3
8 PM Sat 76 76 N 7 4145 4000 0 Blue 0
9 PM Sat 75 75 N 7 3820 4000 0 Blue 0
10 PM Sat 74 74 N 7 3492 4000 0 Blue 0
11 PM Sat 73 73 NE 6 3161 4000 0 Blue 0
12 Midnight Sun 72 72 NE 6 2917 4000 0 Blue 0
1 AM Sun 71 71 NE 6 2917 4000 0 Blue 0
2 AM Sun 70 70 N 6 2917 4000 0 Blue 0
3 AM Sun 69 69 N 6 2917 4000 0 Blue 0
4 AM Sun 69 69 N 6 2917 4000 0 Blue 0
5 AM Sun 68 68 NE 2 2917 4000 0 Blue 0
6 AM Sun 66 66 NE 2 2917 4000 0 Blue 0
7 AM Sun 65 65 NE 2 2917 4000 0 Blue 0
8 AM Sun 65 65 NE 2 2917 4000 0 Blue 0
9 AM Sun 70 72 NE 2 2917 4000 0 Blue 0
10 AM Sun 75 78 NE 2 4682 4000 0 Blue 1
11 AM Sun 80 85 SW 6 7337 6024 2024 Blue 8
12 Noon Sun 83 89 SW 6 10174 7959 3959 Blue 12
1 PM Sun 85 92 SW 6 12946 10045 6045 Blue 15
2 PM Sun 85 92 SW 6 12946 10045 6045 Blue 15
3 PM Sun 85 90 SW 6 11073 8693 4693 Blue 13
4 PM Sun 85 89 SW 6 10174 7959 3959 Blue 12
5 PM Sun 83 85 W 9 7337 6024 2024 Blue 8
6 PM Sun 79 79 W 9 4837 4142 142 Blue 2
7 PM Sun 73 73 W 9 3161 4000 0 Blue 0
8 PM Sun 68 68 W 9 2917 4000 0 Blue 0
9 PM Sun 66 66 W 9 2917 4000 0 Blue 0
10 PM Sun 65 65 W 9 2917 4000 0 Blue 0
11 PM Sun 64 64 NE 6 2917 4000 0 Blue 0
12 Midnight Mon 63 63 NE 6 2917 4000 0 Blue 0
1 AM Mon 62 62 NE 6 2917 4000 0 Blue 0
2 AM Mon 62 62 NE 6 2917 4000 0 Blue 0
3 AM Mon 61 61 NE 6 2917 4000 0 Blue 0
4 AM Mon 61 61 NE 6 2917 4000 0 Blue 0
5 AM Mon 60 60 E 5 2917 4000 0 Blue 0
6 AM Mon 59 59 E 5 2917 4000 0 Blue 0
7 AM Mon 58 58 E 5 2917 4000 0 Blue 0
8 AM Mon 59 59 E 5 2917 4000 0 Blue 0
9 AM Mon 63 65 E 5 2917 4000 0 Blue 0
10 AM Mon 69 72 E 5 2917 4000 0 Blue 0
11 AM Mon 75 80 S 6 5158 4462 462 Blue 3
12 Noon Mon 79 85 S 6 7337 6024 2024 Blue 8
1 PM Mon 81 88 S 6 9507 7292 3292 Blue 11
2 PM Mon 82 89 S 6 10174 7959 3959 Blue 12
3 PM Mon 83 88 S 6 9507 7292 3292 Blue 11
4 PM Mon 82 86 S 6 8058 6454 2454 Blue 9
5 PM Mon 80 82 SW 5 6053 4832 832 Blue 5
6 PM Mon 76 76 SW 5 4145 4000 0 Blue 0
7 PM Mon 71 71 SW 5 2917 4000 0 Blue 0
8 PM Mon 67 67 SW 5 2917 4000 0 Blue 0
9 PM Mon 65 65 SW 5 2917 4000 0 Blue 0
10 PM Mon 65 65 SW 5 2917 4000 0 Blue 0
11 PM Mon 65 65 E 5 2917 4000 0 Blue 0
12 Midnight Tue 65 65 E 5 2917 4000 0 Blue 0
1 AM Tue 64 64 E 5 2917 4000 0 Blue 0
2 AM Tue 64 64 E 5 2917 4000 0 Blue 0
3 AM Tue 63 63 E 5 2917 4000 0 Blue 0
4 AM Tue 62 62 E 5 2917 4000 0 Blue 0
5 AM Tue 61 61 SE 5 2917 4000 0 Blue 0
6 AM Tue 59 59 SE 5 2917 4000 0 Blue 0
7 AM Tue 58 58 SE 5 2917 4000 0 Blue 0
8 AM Tue 59 59 SE 5 2917 4000 0 Blue 0
9 AM Tue 63 65 SE 5 2917 4000 0 Blue 0
10 AM Tue 68 71 SE 5 2917 4000 0 Blue 0
11 AM Tue 73 78 S 8 4682 4000 0 Blue 1
12 Noon Tue 77 83 S 8 6488 5140 1140 Blue 6
1 PM Tue 79 86 S 8 8058 6454 2454 Blue 9
2 PM Tue 80 87 S 8 8804 6876 2876 Blue 10
3 PM Tue 80 85 S 8 7337 6024 2024 Blue 8
4 PM Tue 79 83 S 8 6488 5140 1140 Blue 6
5 PM Tue 77 79 SW 9 4837 4142 142 Blue 2
6 PM Tue 74 74 SW 9 3492 4000 0 Blue 0
7 PM Tue 69 69 SW 9 2917 4000 0 Blue 0
8 PM Tue 66 66 SW 9 2917 4000 0 Blue 0
9 PM Tue 64 64 SW 9 2917 4000 0 Blue 0
10 PM Tue 64 64 SW 9 2917 4000 0 Blue 0
11 PM Tue 64 64 SE 5 2917 4000 0 Blue 0
12 Midnight Wed 63 63 SE 5 2917 4000 0 Blue 0
1 AM Wed 63 63 SE 5 2917 4000 0 Blue 0
2 AM Wed 63 63 SE 5 2917 4000 0 Blue 0
3 AM Wed 62 62 SE 5 2917 4000 0 Blue 0
4 AM Wed 61 61 SE 5 2917 4000 0 Blue 0
5 AM Wed 60 60 SE 5 2917 4000 0 Blue 0
6 AM Wed 58 58 SE 5 2917 4000 0 Blue 0
7 AM Wed 56 56 SE 5 2917 4000 0 Blue 0
8 AM Wed 56 56 SE 5 2917 4000 0 Blue 0
9 AM Wed 58 60 SE 5 2917 4000 0 Blue 0
10 AM Wed 62 65 SE 5 2917 4000 0 Blue 0
11 AM Wed 66 71 SW 7 2917 4000 0 Blue 0
12 Noon Wed 69 75 SW 7 3820 4000 0 Blue 0
1 PM Wed 71 78 SW 7 4682 4000 0 Blue 1
2 PM Wed 73 80 SW 7 5158 4462 462 Blue 3
3 PM Wed 74 79 SW 7 4837 4142 142 Blue 2
4 PM Wed 75 79 SW 7 4837 4142 142 Blue 2
5 PM Wed 74 76 W 8 4145 4000 0 Blue 0
6 PM Wed 69 69 W 8 2917 4000 0 Blue 0
7 PM Wed 64 64 W 8 2917 4000 0 Blue 0
8 PM Wed 61 61 W 8 2917 4000 0 Blue 0
9 PM Wed 61 61 W 8 2917 4000 0 Blue 0
10 PM Wed 63 63 W 8 2917 4000 0 Blue 0
11 PM Wed 64 64 N 3 2917 4000 0 Blue 0
12 Midnight Thu 62 62 N 3 2917 4000 0 Blue 0
1 AM Thu 60 60 N 3 2917 4000 0 Blue 0
2 AM Thu 58 58 N 3 2917 4000 0 Blue 0
3 AM Thu 56 56 N 3 2917 4000 0 Blue 0
4 AM Thu 56 56 N 3 2917 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 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