Detailed Predictions for: Timberline
Launch Altitude (f): 5810
LZ Altitude (f): 1840
Sounding

Station:

KOAK

Date/Time:

25 AUG 2019

Temp/Wind data from:

NOAA Digital Forecast

Site Forecasts
Time
(Local)
High
Temp

Puddle
Temp

Wind
(mph)
Thermal
Ceiling

(ft)
Soaring
Ceiling

(ft)
Above
Launch

(ft)
Thermal
Type
Thermal
Index

(F)
5 AM Sun 64 64 W 3 4442 5810 0 Blue 0
6 AM Sun 70 70 W 3 4442 5810 0 Blue 0
7 AM Sun 64 64 W 3 4442 5810 0 Blue 0
8 AM Sun 70 70 S 3 4442 5810 0 Blue 0
9 AM Sun 73 74 S 3 5952 5810 0 Blue 2
10 AM Sun 74 77 S 3 7073 5935 125 Blue 5
11 AM Sun 75 80 SW 7 7531 7053 1243 Blue 8
12 Noon Sun 78 84 SW 7 9121 8135 2325 Blue 12
1 PM Sun 79 86 SW 7 9640 8854 3044 Blue 14
2 PM Sun 81 88 SW 10 10616 9343 3533 Blue 16
3 PM Sun 81 87 SW 10 9897 9085 3275 Blue 15
4 PM Sun 81 85 SW 10 9381 8648 2838 Blue 13
5 PM Sun 80 82 SW 8 8673 7410 1600 Blue 10
6 PM Sun 78 79 SW 8 7420 6782 972 Blue 7
7 PM Sun 76 76 SW 8 6800 5810 0 Blue 4
8 PM Sun 70 70 W 6 4442 5810 0 Blue 0
9 PM Sun 69 69 W 6 4442 5810 0 Blue 0
10 PM Sun 68 68 W 6 4442 5810 0 Blue 0
11 PM Sun 68 68 N 5 4442 5810 0 Blue 0
12 Midnight Mon 68 68 N 5 4442 5810 0 Blue 0
1 AM Mon 68 68 N 5 4442 5810 0 Blue 0
2 AM Mon 66 66 NE 6 4442 5810 0 Blue 0
3 AM Mon 66 66 NE 6 4442 5810 0 Blue 0
4 AM Mon 66 66 NE 6 4442 5810 0 Blue 0
5 AM Mon 65 65 NE 6 4442 5810 0 Blue 0
6 AM Mon 65 65 NE 6 4442 5810 0 Blue 0
7 AM Mon 65 65 NE 6 4442 5810 0 Blue 0
8 AM Mon 70 70 E 6 4442 5810 0 Blue 0
9 AM Mon 73 74 E 6 5952 5810 0 Blue 2
10 AM Mon 75 78 E 6 7308 6394 584 Blue 6
11 AM Mon 77 82 S 5 8673 7410 1600 Blue 10
12 Noon Mon 80 86 S 5 9640 8854 3044 Blue 14
1 PM Mon 81 88 S 5 10616 9343 3533 Blue 16
2 PM Mon 82 89 SW 6 10761 9600 3790 Blue 17
3 PM Mon 83 89 SW 6 10761 9600 3790 Blue 17
4 PM Mon 83 87 SW 6 9897 9085 3275 Blue 15
5 PM Mon 82 84 SW 7 9121 8135 2325 Blue 12
6 PM Mon 79 80 SW 7 7531 7053 1243 Blue 8
7 PM Mon 76 76 SW 7 6800 5810 0 Blue 4
8 PM Mon 73 73 SW 7 5477 5810 0 Blue 1
9 PM Mon 71 71 SW 7 4442 5810 0 Blue 0
10 PM Mon 70 70 SW 7 4442 5810 0 Blue 0
11 PM Mon 69 69 N 5 4442 5810 0 Blue 0
12 Midnight Tue 69 69 N 5 4442 5810 0 Blue 0
1 AM Tue 69 69 N 5 4442 5810 0 Blue 0
2 AM Tue 68 68 N 5 4442 5810 0 Blue 0
3 AM Tue 68 68 N 5 4442 5810 0 Blue 0
4 AM Tue 67 67 N 5 4442 5810 0 Blue 0
5 AM Tue 67 67 NE 6 4442 5810 0 Blue 0
6 AM Tue 68 68 NE 6 4442 5810 0 Blue 0
7 AM Tue 69 69 NE 6 4442 5810 0 Blue 0
8 AM Tue 71 71 NE 6 4442 5810 0 Blue 0
9 AM Tue 74 75 NE 6 6418 5810 0 Blue 3
10 AM Tue 77 80 NE 6 7531 7053 1243 Blue 8
11 AM Tue 79 84 W 7 9121 8135 2325 Blue 12
12 Noon Tue 81 87 W 7 9897 9085 3275 Blue 15
1 PM Tue 82 89 W 7 10761 9600 3790 Blue 17
2 PM Tue 83 90 W 7 10906 9856 4046 Blue 18
3 PM Tue 83 89 W 7 10761 9600 3790 Blue 17
4 PM Tue 83 87 W 7 9897 9085 3275 Blue 15
5 PM Tue 82 84 SW 9 9121 8135 2325 Blue 12
6 PM Tue 79 80 SW 9 7531 7053 1243 Blue 8
7 PM Tue 76 76 SW 9 6800 5810 0 Blue 4
8 PM Tue 73 73 SW 9 5477 5810 0 Blue 1
9 PM Tue 71 71 SW 9 4442 5810 0 Blue 0
10 PM Tue 71 71 SW 9 4442 5810 0 Blue 0
11 PM Tue 70 70 W 8 4442 5810 0 Blue 0
12 Midnight Wed 70 70 W 8 4442 5810 0 Blue 0
1 AM Wed 69 69 W 8 4442 5810 0 Blue 0
2 AM Wed 69 69 W 8 4442 5810 0 Blue 0
3 AM Wed 69 69 W 8 4442 5810 0 Blue 0
4 AM Wed 68 68 W 8 4442 5810 0 Blue 0
5 AM Wed 68 68 NW 7 4442 5810 0 Blue 0
6 AM Wed 68 68 NW 7 4442 5810 0 Blue 0
7 AM Wed 69 69 NW 7 4442 5810 0 Blue 0
8 AM Wed 70 70 NW 7 4442 5810 0 Blue 0
9 AM Wed 73 74 NW 7 5952 5810 0 Blue 2
10 AM Wed 75 77 NW 7 7073 5935 125 Blue 5
11 AM Wed 77 81 SW 9 8359 7299 1489 Blue 9
12 Noon Wed 79 84 SW 9 9121 8135 2325 Blue 12
1 PM Wed 80 86 SW 9 9640 8854 3044 Blue 14
2 PM Wed 80 85 SW 9 9381 8648 2838 Blue 13
3 PM Wed 80 85 SW 9 9381 8648 2838 Blue 13
4 PM Wed 80 83 SW 9 8880 7521 1711 Blue 11
5 PM Wed 79 81 SW 12 8359 7299 1489 Blue 9
6 PM Wed 76 77 SW 12 7073 5935 125 Blue 5
7 PM Wed 74 74 SW 12 5952 5810 0 Blue 2
8 PM Wed 71 71 SW 12 4442 5810 0 Blue 0
9 PM Wed 69 69 SW 12 4442 5810 0 Blue 0
10 PM Wed 68 68 SW 12 4442 5810 0 Blue 0
11 PM Wed 67 67 NW 5 4442 5810 0 Blue 0
12 Midnight Thu 67 67 NW 5 4442 5810 0 Blue 0
1 AM Thu 67 67 NW 5 4442 5810 0 Blue 0
2 AM Thu 66 66 NW 5 4442 5810 0 Blue 0
3 AM Thu 66 66 NW 5 4442 5810 0 Blue 0
4 AM Thu 65 65 NW 5 4442 5810 0 Blue 0
5 AM Thu 65 65 SW 5 4442 5810 0 Blue 0
6 AM Thu 66 66 SW 5 4442 5810 0 Blue 0
7 AM Thu 67 67 SW 5 4442 5810 0 Blue 0
8 AM Thu 69 69 SW 5 4442 5810 0 Blue 0
9 AM Thu 70 71 SW 5 4442 5810 0 Blue 0
10 AM Thu 72 75 SW 5 6418 5810 0 Blue 3
11 AM Thu 74 79 SW 8 7420 6782 972 Blue 7
12 Noon Thu 75 81 SW 8 8359 7299 1489 Blue 9
1 PM Thu 75 82 SW 8 8673 7410 1600 Blue 10
2 PM Thu 76 83 SW 8 8880 7521 1711 Blue 11
3 PM Thu 77 83 SW 8 8880 7521 1711 Blue 11
4 PM Thu 77 81 SW 8 8359 7299 1489 Blue 9
5 PM Thu 76 78 SW 9 7308 6394 584 Blue 6
6 PM Thu 74 75 SW 9 6418 5810 0 Blue 3
7 PM Thu 72 72 SW 9 4940 5810 0 Blue 0
8 PM Thu 70 70 SW 9 4442 5810 0 Blue 0
9 PM Thu 68 68 SW 9 4442 5810 0 Blue 0
10 PM Thu 67 67 SW 9 4442 5810 0 Blue 0
11 PM Thu 67 67 NW 6 4442 5810 0 Blue 0
12 Midnight Fri 67 67 NW 6 4442 5810 0 Blue 0
1 AM Fri 66 66 NW 6 4442 5810 0 Blue 0
2 AM Fri 66 66 NW 6 4442 5810 0 Blue 0
3 AM Fri 65 65 NW 6 4442 5810 0 Blue 0
4 AM Fri 64 64 NW 6 4442 5810 0 Blue 0
5 AM Fri 64 64 W 6 4442 5810 0 Blue 0
6 AM Fri 65 65 W 6 4442 5810 0 Blue 0
7 AM Fri 67 67 W 6 4442 5810 0 Blue 0
8 AM Fri 68 68 W 6 4442 5810 0 Blue 0
9 AM Fri 70 71 W 6 4442 5810 0 Blue 0
10 AM Fri 71 74 W 6 5952 5810 0 Blue 2
11 AM Fri 73 78 SW 8 7308 6394 584 Blue 6
12 Noon Fri 75 81 SW 8 8359 7299 1489 Blue 9
1 PM Fri 76 83 SW 8 8880 7521 1711 Blue 11
2 PM Fri 77 84 SW 8 9121 8135 2325 Blue 12
3 PM Fri 78 84 SW 8 9121 8135 2325 Blue 12
4 PM Fri 78 82 SW 8 8673 7410 1600 Blue 10
5 PM Fri 76 78 W 8 7308 6394 584 Blue 6
6 PM Fri 74 75 W 8 6418 5810 0 Blue 3
7 PM Fri 71 71 W 8 4442 5810 0 Blue 0
8 PM Fri 69 69 W 8 4442 5810 0 Blue 0
9 PM Fri 67 67 W 8 4442 5810 0 Blue 0
10 PM Fri 67 67 W 8 4442 5810 0 Blue 0
11 PM Fri 66 66 SW 7 4442 5810 0 Blue 0
12 Midnight Sat 66 66 SW 7 4442 5810 0 Blue 0
1 AM Sat 66 66 SW 7 4442 5810 0 Blue 0
2 AM Sat 65 65 SW 7 4442 5810 0 Blue 0
3 AM Sat 64 64 SW 7 4442 5810 0 Blue 0
4 AM Sat 63 63 SW 7 4442 5810 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