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

Station:

KOAK

Date/Time:

19 AUG 2018

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 66 66 SE 6 3711 5810 0 Blue 0
6 AM Sun 65 65 SE 6 3711 5810 0 Blue 0
7 AM Sun 65 65 SE 6 3711 5810 0 Blue 0
8 AM Sun 67 67 SE 5 3711 5810 0 Blue 0
9 AM Sun 71 72 SE 5 3711 5810 0 Blue 0
10 AM Sun 76 79 SE 5 6642 5810 0 Blue 3
11 AM Sun 80 85 S 5 9262 7762 1952 Blue 9
12 Noon Sun 83 89 S 5 11222 9654 3844 Blue 13
1 PM Sun 84 91 S 5 12295 10553 4743 Blue 15
2 PM Sun 85 92 SW 8 12732 11110 5300 Blue 16
3 PM Sun 86 92 SW 8 12732 11110 5300 Blue 16
4 PM Sun 86 90 SW 8 11767 10102 4292 Blue 14
5 PM Sun 84 87 W 9 10178 8729 2919 Blue 11
6 PM Sun 81 82 W 9 7809 6628 818 Blue 6
7 PM Sun 76 76 W 9 5185 5810 0 Blue 0
8 PM Sun 73 73 NW 7 3711 5810 0 Blue 0
9 PM Sun 70 70 NW 7 3711 5810 0 Blue 0
10 PM Sun 69 69 NW 7 3711 5810 0 Blue 0
11 PM Sun 69 69 N 3 3711 5810 0 Blue 0
12 Midnight Mon 68 68 N 3 3711 5810 0 Blue 0
1 AM Mon 67 67 N 3 3711 5810 0 Blue 0
2 AM Mon 67 67 E 6 3711 5810 0 Blue 0
3 AM Mon 66 66 E 6 3711 5810 0 Blue 0
4 AM Mon 65 65 E 6 3711 5810 0 Blue 0
5 AM Mon 64 64 NE 5 3711 5810 0 Blue 0
6 AM Mon 64 64 NE 5 3711 5810 0 Blue 0
7 AM Mon 64 64 NE 5 3711 5810 0 Blue 0
8 AM Mon 66 66 NE 5 3711 5810 0 Blue 0
9 AM Mon 69 70 NE 5 3711 5810 0 Blue 0
10 AM Mon 74 77 NE 5 5851 5810 0 Blue 1
11 AM Mon 78 83 E 6 8305 6860 1050 Blue 7
12 Noon Mon 80 87 E 6 10178 8729 2919 Blue 11
1 PM Mon 82 89 E 6 11222 9654 3844 Blue 13
2 PM Mon 83 90 SE 8 11767 10102 4292 Blue 14
3 PM Mon 84 90 SE 8 11767 10102 4292 Blue 14
4 PM Mon 84 89 SE 8 11222 9654 3844 Blue 13
5 PM Mon 83 86 S 6 9725 8251 2441 Blue 10
6 PM Mon 79 80 S 6 6875 5829 19 Blue 4
7 PM Mon 75 75 S 6 4487 5810 0 Blue 0
8 PM Mon 71 71 S 6 3711 5810 0 Blue 0
9 PM Mon 69 69 S 6 3711 5810 0 Blue 0
10 PM Mon 68 68 S 6 3711 5810 0 Blue 0
11 PM Mon 67 67 S 5 3711 5810 0 Blue 0
12 Midnight Tue 66 66 S 5 3711 5810 0 Blue 0
1 AM Tue 66 66 S 5 3711 5810 0 Blue 0
2 AM Tue 65 65 S 5 3711 5810 0 Blue 0
3 AM Tue 64 64 S 5 3711 5810 0 Blue 0
4 AM Tue 64 64 S 5 3711 5810 0 Blue 0
5 AM Tue 64 64 SE 7 3711 5810 0 Blue 0
6 AM Tue 63 63 SE 7 3711 5810 0 Blue 0
7 AM Tue 63 63 SE 7 3711 5810 0 Blue 0
8 AM Tue 64 64 SE 7 3711 5810 0 Blue 0
9 AM Tue 68 69 SE 7 3711 5810 0 Blue 0
10 AM Tue 72 75 SE 7 4487 5810 0 Blue 0
11 AM Tue 76 81 S 7 7300 6395 585 Blue 5
12 Noon Tue 78 84 S 7 8789 7260 1450 Blue 8
1 PM Tue 80 87 S 7 10178 8729 2919 Blue 11
2 PM Tue 81 88 S 7 10659 9196 3386 Blue 12
3 PM Tue 82 88 S 7 10659 9196 3386 Blue 12
4 PM Tue 82 86 S 7 9725 8251 2441 Blue 10
5 PM Tue 80 83 S 7 8305 6860 1050 Blue 7
6 PM Tue 77 78 S 7 6407 5810 0 Blue 2
7 PM Tue 72 72 S 7 3711 5810 0 Blue 0
8 PM Tue 68 68 S 7 3711 5810 0 Blue 0
9 PM Tue 66 66 S 7 3711 5810 0 Blue 0
10 PM Tue 65 65 S 7 3711 5810 0 Blue 0
11 PM Tue 64 64 E 3 3711 5810 0 Blue 0
12 Midnight Wed 64 64 E 3 3711 5810 0 Blue 0
1 AM Wed 63 63 E 3 3711 5810 0 Blue 0
2 AM Wed 63 63 E 3 3711 5810 0 Blue 0
3 AM Wed 62 62 E 3 3711 5810 0 Blue 0
4 AM Wed 62 62 E 3 3711 5810 0 Blue 0
5 AM Wed 61 61 NE 5 3711 5810 0 Blue 0
6 AM Wed 61 61 NE 5 3711 5810 0 Blue 0
7 AM Wed 61 61 NE 5 3711 5810 0 Blue 0
8 AM Wed 63 63 NE 5 3711 5810 0 Blue 0
9 AM Wed 66 67 NE 5 3711 5810 0 Blue 0
10 AM Wed 71 74 NE 5 3753 5810 0 Blue 0
11 AM Wed 75 80 SW 6 6875 5829 19 Blue 4
12 Noon Wed 78 84 SW 6 8789 7260 1450 Blue 8
1 PM Wed 80 87 SW 6 10178 8729 2919 Blue 11
2 PM Wed 81 88 SW 6 10659 9196 3386 Blue 12
3 PM Wed 82 88 SW 6 10659 9196 3386 Blue 12
4 PM Wed 82 86 SW 6 9725 8251 2441 Blue 10
5 PM Wed 80 83 SW 8 8305 6860 1050 Blue 7
6 PM Wed 76 77 SW 8 5851 5810 0 Blue 1
7 PM Wed 72 72 SW 8 3711 5810 0 Blue 0
8 PM Wed 68 68 SW 8 3711 5810 0 Blue 0
9 PM Wed 66 66 SW 8 3711 5810 0 Blue 0
10 PM Wed 65 65 SW 8 3711 5810 0 Blue 0
11 PM Wed 65 65 NW 2 3711 5810 0 Blue 0
12 Midnight Thu 64 64 NW 2 3711 5810 0 Blue 0
1 AM Thu 63 63 NW 2 3711 5810 0 Blue 0
2 AM Thu 63 63 NW 2 3711 5810 0 Blue 0
3 AM Thu 63 63 NW 2 3711 5810 0 Blue 0
4 AM Thu 63 63 NW 2 3711 5810 0 Blue 0
5 AM Thu 62 62 E 6 3711 5810 0 Blue 0
6 AM Thu 62 62 E 6 3711 5810 0 Blue 0
7 AM Thu 62 62 E 6 3711 5810 0 Blue 0
8 AM Thu 64 64 E 6 3711 5810 0 Blue 0
9 AM Thu 68 70 E 6 3711 5810 0 Blue 0
10 AM Thu 72 75 E 6 4487 5810 0 Blue 0
11 AM Thu 76 81 E 3 7300 6395 585 Blue 5
12 Noon Thu 79 85 E 3 9262 7762 1952 Blue 9
1 PM Thu 80 87 E 3 10178 8729 2919 Blue 11
2 PM Thu 81 88 E 3 10659 9196 3386 Blue 12
3 PM Thu 82 88 E 3 10659 9196 3386 Blue 12
4 PM Thu 82 86 E 3 9725 8251 2441 Blue 10
5 PM Thu 81 84 W 7 8789 7260 1450 Blue 8
6 PM Thu 77 78 W 7 6407 5810 0 Blue 2
7 PM Thu 73 73 W 7 3711 5810 0 Blue 0
8 PM Thu 70 70 W 7 3711 5810 0 Blue 0
9 PM Thu 68 68 W 7 3711 5810 0 Blue 0
10 PM Thu 67 67 W 7 3711 5810 0 Blue 0
11 PM Thu 66 66 NW 5 3711 5810 0 Blue 0
12 Midnight Fri 65 65 NW 5 3711 5810 0 Blue 0
1 AM Fri 65 65 NW 5 3711 5810 0 Blue 0
2 AM Fri 64 64 NW 5 3711 5810 0 Blue 0
3 AM Fri 63 63 NW 5 3711 5810 0 Blue 0
4 AM Fri 63 63 NW 5 3711 5810 0 Blue 0
5 AM Fri 62 62 NE 5 3711 5810 0 Blue 0
6 AM Fri 62 62 NE 5 3711 5810 0 Blue 0
7 AM Fri 62 62 NE 5 3711 5810 0 Blue 0
8 AM Fri 64 64 NE 5 3711 5810 0 Blue 0
9 AM Fri 67 69 NE 5 3711 5810 0 Blue 0
10 AM Fri 72 75 NE 5 4487 5810 0 Blue 0
11 AM Fri 76 81 E 3 7300 6395 585 Blue 5
12 Noon Fri 78 84 E 3 8789 7260 1450 Blue 8
1 PM Fri 80 87 E 3 10178 8729 2919 Blue 11
2 PM Fri 80 87 E 3 10178 8729 2919 Blue 11
3 PM Fri 81 87 E 3 10178 8729 2919 Blue 11
4 PM Fri 81 85 E 3 9262 7762 1952 Blue 9
5 PM Fri 80 83 W 8 8305 6860 1050 Blue 7
6 PM Fri 77 78 W 8 6407 5810 0 Blue 2
7 PM Fri 73 73 W 8 3711 5810 0 Blue 0
8 PM Fri 70 70 W 8 3711 5810 0 Blue 0
9 PM Fri 68 68 W 8 3711 5810 0 Blue 0
10 PM Fri 67 67 W 8 3711 5810 0 Blue 0
11 PM Fri 67 67 NW 2 3711 5810 0 Blue 0
12 Midnight Sat 66 66 NW 2 3711 5810 0 Blue 0
1 AM Sat 66 66 NW 2 3711 5810 0 Blue 0
2 AM Sat 65 65 NW 2 3711 5810 0 Blue 0
3 AM Sat 64 64 NW 2 3711 5810 0 Blue 0
4 AM Sat 64 64 NW 2 3711 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