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

Station:

KOAK

Date/Time:

22 SEP 2017

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 Fri 42 42 NE 7 4626 5810 0 Blue 0
6 AM Fri 42 42 NE 7 4626 5810 0 Blue 0
7 AM Fri 42 42 NE 7 4626 5810 0 Blue 0
8 AM Fri 44 44 NE 3 4631 5810 0 Blue 0
9 AM Fri 46 46 NE 3 5470 5810 0 Blue 2
10 AM Fri 49 50 NE 3 8050 5932 122 Blue 6
11 AM Fri 52 53 S 6 10718 7968 2158 Blue 9
12 Noon Fri 54 56 S 6 11833 10648 4838 Blue 12
1 PM Fri 55 57 S 6 12334 10993 5183 Blue 13
2 PM Fri 56 58 W 6 12821 11334 5524 Blue 14
3 PM Fri 56 58 W 6 12821 11334 5524 Blue 14
4 PM Fri 56 57 W 6 12334 10993 5183 Blue 13
5 PM Fri 55 55 N 2 11410 9347 3537 Blue 11
6 PM Fri 53 53 N 2 10718 7968 2158 Blue 9
7 PM Fri 51 51 N 2 8407 6401 591 Blue 7
8 PM Fri 49 49 N 3 7264 5810 0 Blue 5
9 PM Fri 49 49 N 3 7264 5810 0 Blue 5
10 PM Fri 48 48 N 3 6426 5810 0 Blue 4
11 PM Fri 48 48 NE 10 6426 5810 0 Blue 4
12 Midnight Sat 48 48 NE 10 6426 5810 0 Blue 4
1 AM Sat 47 47 NE 10 5951 5810 0 Blue 3
2 AM Sat 47 47 N 10 5951 5810 0 Blue 3
3 AM Sat 47 47 N 10 5951 5810 0 Blue 3
4 AM Sat 47 47 N 10 5951 5810 0 Blue 3
5 AM Sat 47 47 N 9 5951 5810 0 Blue 3
6 AM Sat 47 47 N 9 5951 5810 0 Blue 3
7 AM Sat 47 47 N 9 5951 5810 0 Blue 3
8 AM Sat 49 49 N 9 7264 5810 0 Blue 5
9 AM Sat 52 53 N 9 10718 7968 2158 Blue 9
10 AM Sat 56 58 N 9 12821 11334 5524 Blue 14
11 AM Sat 60 64 N 10 14088 13407 7597 Blue 20
12 Noon Sat 63 68 N 10 14960 14252 8442 Blue 24
1 PM Sat 65 70 N 10 15323 14715 8905 Blue 26
2 PM Sat 66 71 N 10 15504 14896 9086 Blue 27
3 PM Sat 67 71 N 10 15504 14896 9086 Blue 27
4 PM Sat 67 70 N 10 15323 14715 8905 Blue 26
5 PM Sat 66 67 N 8 14779 14009 8199 Blue 23
6 PM Sat 63 63 N 8 13842 13239 7429 Blue 19
7 PM Sat 60 60 N 8 13299 12208 6398 Blue 16
8 PM Sat 57 57 N 8 12334 10993 5183 Blue 13
9 PM Sat 55 55 N 8 11410 9347 3537 Blue 11
10 PM Sat 55 55 N 8 11410 9347 3537 Blue 11
11 PM Sat 54 54 NE 10 11066 8365 2555 Blue 10
12 Midnight Sun 54 54 NE 10 11066 8365 2555 Blue 10
1 AM Sun 53 53 NE 10 10718 7968 2158 Blue 9
2 AM Sun 53 53 NE 10 10718 7968 2158 Blue 9
3 AM Sun 52 52 NE 10 9913 7198 1388 Blue 8
4 AM Sun 52 52 NE 10 9913 7198 1388 Blue 8
5 AM Sun 51 51 NE 10 8407 6401 591 Blue 7
6 AM Sun 51 51 NE 10 8407 6401 591 Blue 7
7 AM Sun 51 51 NE 10 8407 6401 591 Blue 7
8 AM Sun 53 53 NE 10 10718 7968 2158 Blue 9
9 AM Sun 56 57 NE 10 12334 10993 5183 Blue 13
10 AM Sun 60 62 NE 10 13594 13034 7224 Blue 18
11 AM Sun 63 66 NE 7 14577 13764 7954 Blue 22
12 Noon Sun 66 70 NE 7 15323 14715 8905 Blue 26
1 PM Sun 67 72 NE 7 15669 15076 9266 Blue 28
2 PM Sun 68 73 NE 7 15804 15256 9446 Blue 29
3 PM Sun 69 73 NE 7 15804 15256 9446 Blue 29
4 PM Sun 69 71 NE 7 15504 14896 9086 Blue 27
5 PM Sun 68 69 NW 7 15142 14494 8684 Blue 25
6 PM Sun 65 65 NW 7 14333 13535 7725 Blue 21
7 PM Sun 62 62 NW 7 13594 13034 7224 Blue 18
8 PM Sun 59 59 NW 7 13093 11712 5902 Blue 15
9 PM Sun 58 58 NW 7 12821 11334 5524 Blue 14
10 PM Sun 57 57 NW 7 12334 10993 5183 Blue 13
11 PM Sun 57 57 N 6 12334 10993 5183 Blue 13
12 Midnight Mon 57 57 N 6 12334 10993 5183 Blue 13
1 AM Mon 56 56 N 6 11833 10648 4838 Blue 12
2 AM Mon 56 56 N 6 11833 10648 4838 Blue 12
3 AM Mon 56 56 N 6 11833 10648 4838 Blue 12
4 AM Mon 56 56 N 6 11833 10648 4838 Blue 12
5 AM Mon 56 56 NE 8 11833 10648 4838 Blue 12
6 AM Mon 55 55 NE 8 11410 9347 3537 Blue 11
7 AM Mon 55 55 NE 8 11410 9347 3537 Blue 11
8 AM Mon 56 56 NE 8 11833 10648 4838 Blue 12
9 AM Mon 59 60 NE 8 13299 12208 6398 Blue 16
10 AM Mon 63 65 NE 8 14333 13535 7725 Blue 21
11 AM Mon 67 70 N 7 15323 14715 8905 Blue 26
12 Noon Mon 70 75 N 7 16142 15615 9805 Blue 31
1 PM Mon 71 76 N 7 16330 15752 9942 Blue 32
2 PM Mon 72 77 N 7 16544 15885 10075 Blue 33
3 PM Mon 73 77 N 7 16544 15885 10075 Blue 33
4 PM Mon 73 76 N 7 16330 15752 9942 Blue 32
5 PM Mon 72 73 N 6 15804 15256 9446 Blue 29
6 PM Mon 69 69 N 6 15142 14494 8684 Blue 25
7 PM Mon 66 66 N 6 14577 13764 7954 Blue 22
8 PM Mon 63 63 N 6 13842 13239 7429 Blue 19
9 PM Mon 61 61 N 6 13446 12689 6879 Blue 17
10 PM Mon 61 61 N 6 13446 12689 6879 Blue 17
11 PM Mon 60 60 N 8 13299 12208 6398 Blue 16
12 Midnight Tue 60 60 N 8 13299 12208 6398 Blue 16
1 AM Tue 59 59 N 8 13093 11712 5902 Blue 15
2 AM Tue 59 59 N 8 13093 11712 5902 Blue 15
3 AM Tue 59 59 N 8 13093 11712 5902 Blue 15
4 AM Tue 59 59 N 8 13093 11712 5902 Blue 15
5 AM Tue 58 58 NE 8 12821 11334 5524 Blue 14
6 AM Tue 58 58 NE 8 12821 11334 5524 Blue 14
7 AM Tue 58 58 NE 8 12821 11334 5524 Blue 14
8 AM Tue 59 59 NE 8 13093 11712 5902 Blue 15
9 AM Tue 62 63 NE 8 13842 13239 7429 Blue 19
10 AM Tue 67 69 NE 8 15142 14494 8684 Blue 25
11 AM Tue 71 74 NE 7 15954 15436 9626 Blue 30
12 Noon Tue 74 79 NE 7 17369 16254 10444 Blue 35
1 PM Tue 75 80 NE 7 17770 16440 10630 Blue 36
2 PM Tue 77 82 NE 7 18329 17189 11379 White 38
3 PM Tue 77 81 NE 7 18128 16783 10973 White 37
4 PM Tue 77 80 NE 7 17770 16440 10630 Blue 36
5 PM Tue 75 76 N 7 16330 15752 9942 Blue 32
6 PM Tue 73 73 N 7 15804 15256 9446 Blue 29
7 PM Tue 69 69 N 7 15142 14494 8684 Blue 25
8 PM Tue 67 67 N 7 14779 14009 8199 Blue 23
9 PM Tue 65 65 N 7 14333 13535 7725 Blue 21
10 PM Tue 64 64 N 7 14088 13407 7597 Blue 20
11 PM Tue 64 64 NE 5 14088 13407 7597 Blue 20
12 Midnight Wed 64 64 NE 5 14088 13407 7597 Blue 20
1 AM Wed 64 64 NE 5 14088 13407 7597 Blue 20
2 AM Wed 64 64 NE 5 14088 13407 7597 Blue 20
3 AM Wed 64 64 NE 5 14088 13407 7597 Blue 20
4 AM Wed 63 63 NE 5 13842 13239 7429 Blue 19
5 AM Wed 63 63 E 8 13842 13239 7429 Blue 19
6 AM Wed 62 62 E 8 13594 13034 7224 Blue 18
7 AM Wed 61 61 E 8 13446 12689 6879 Blue 17
8 AM Wed 62 62 E 8 13594 13034 7224 Blue 18
9 AM Wed 64 65 E 8 14333 13535 7725 Blue 21
10 AM Wed 68 70 E 8 15323 14715 8905 Blue 26
11 AM Wed 71 74 NE 3 15954 15436 9626 Blue 30
12 Noon Wed 74 77 NE 3 16544 15885 10075 Blue 33
1 PM Wed 75 79 NE 3 17369 16254 10444 Blue 35
2 PM Wed 76 80 NE 3 17770 16440 10630 Blue 36
3 PM Wed 76 79 NE 3 17369 16254 10444 Blue 35
4 PM Wed 75 77 NE 3 16544 15885 10075 Blue 33
5 PM Wed 74 75 W 8 16142 15615 9805 Blue 31
6 PM Wed 71 71 W 8 15504 14896 9086 Blue 27
7 PM Wed 68 68 W 8 14960 14252 8442 Blue 24
8 PM Wed 66 66 W 8 14577 13764 7954 Blue 22
9 PM Wed 65 65 W 8 14333 13535 7725 Blue 21
10 PM Wed 65 65 W 8 14333 13535 7725 Blue 21
11 PM Wed 65 65 NE 7 14333 13535 7725 Blue 21
12 Midnight Thu 65 65 NE 7 14333 13535 7725 Blue 21
1 AM Thu 64 64 NE 7 14088 13407 7597 Blue 20
2 AM Thu 64 64 NE 7 14088 13407 7597 Blue 20
3 AM Thu 64 64 NE 7 14088 13407 7597 Blue 20
4 AM Thu 63 63 NE 7 13842 13239 7429 Blue 19

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