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

Station:

KOAK

Date/Time:

14 DEC 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)
4 AM Fri 40 40 S 17 3740 5810 0 Blue 0
5 AM Fri 40 40 S 17 3740 5810 0 Blue 0
6 AM Fri 40 40 S 17 3740 5810 0 Blue 0
7 AM Fri 40 40 S 20 3740 5810 0 Blue 0
8 AM Fri 40 40 S 20 3740 5810 0 Blue 0
9 AM Fri 41 41 S 20 3740 5810 0 Blue 0
10 AM Fri 41 41 S 21 3740 5810 0 Blue 0
11 AM Fri 41 41 S 21 3740 5810 0 Blue 0
12 Noon Fri 42 42 S 21 3740 5810 0 Blue 0
1 PM Fri 42 42 SW 17 3740 5810 0 Blue 0
2 PM Fri 42 42 SW 17 3740 5810 0 Blue 0
3 PM Fri 42 42 SW 17 3740 5810 0 Blue 0
4 PM Fri 42 42 W 13 3740 5810 0 Blue 0
5 PM Fri 41 41 W 13 3740 5810 0 Blue 0
6 PM Fri 40 40 W 13 3740 5810 0 Blue 0
7 PM Fri 39 39 W 7 3740 5810 0 Blue 0
8 PM Fri 38 38 W 7 3740 5810 0 Blue 0
9 PM Fri 38 38 W 7 3740 5810 0 Blue 0
10 PM Fri 38 38 S 6 3740 5810 0 Blue 0
11 PM Fri 37 37 S 6 3740 5810 0 Blue 0
12 Midnight Sat 37 37 S 6 3740 5810 0 Blue 0
1 AM Sat 37 37 S 6 3740 5810 0 Blue 0
2 AM Sat 37 37 S 6 3740 5810 0 Blue 0
3 AM Sat 37 37 S 6 3740 5810 0 Blue 0
4 AM Sat 37 37 S 7 3740 5810 0 Blue 0
5 AM Sat 37 37 S 7 3740 5810 0 Blue 0
6 AM Sat 37 37 S 7 3740 5810 0 Blue 0
7 AM Sat 38 38 S 7 3740 5810 0 Blue 0
8 AM Sat 38 38 S 7 3740 5810 0 Blue 0
9 AM Sat 39 39 S 7 3740 5810 0 Blue 0
10 AM Sat 40 40 S 10 3740 5810 0 Blue 0
11 AM Sat 40 40 S 10 3740 5810 0 Blue 0
12 Noon Sat 41 41 S 10 3740 5810 0 Blue 0
1 PM Sat 42 42 S 10 3740 5810 0 Blue 0
2 PM Sat 42 42 S 10 3740 5810 0 Blue 0
3 PM Sat 42 42 S 10 3740 5810 0 Blue 0
4 PM Sat 42 42 S 14 3740 5810 0 Blue 0
5 PM Sat 42 42 S 14 3740 5810 0 Blue 0
6 PM Sat 42 42 S 14 3740 5810 0 Blue 0
7 PM Sat 42 42 S 14 3740 5810 0 Blue 0
8 PM Sat 42 42 S 14 3740 5810 0 Blue 0
9 PM Sat 42 42 S 14 3740 5810 0 Blue 0
10 PM Sat 42 42 S 17 3740 5810 0 Blue 0
11 PM Sat 42 42 S 17 3740 5810 0 Blue 0
12 Midnight Sun 42 42 S 17 3740 5810 0 Blue 0
1 AM Sun 42 42 S 17 3740 5810 0 Blue 0
2 AM Sun 42 42 S 17 3740 5810 0 Blue 0
3 AM Sun 42 42 S 17 3740 5810 0 Blue 0
4 AM Sun 42 42 S 20 3740 5810 0 Blue 0
5 AM Sun 44 44 S 20 3740 5810 0 Blue 0
6 AM Sun 45 45 S 20 3740 5810 0 Blue 0
7 AM Sun 46 46 S 20 3740 5810 0 Blue 0
8 AM Sun 46 46 S 20 3740 5810 0 Blue 0
9 AM Sun 45 45 S 20 3740 5810 0 Blue 0
10 AM Sun 44 44 S 23 3740 5810 0 Blue 0
11 AM Sun 45 45 S 23 3740 5810 0 Blue 0
12 Noon Sun 45 45 S 23 3740 5810 0 Blue 0
1 PM Sun 46 46 S 23 3740 5810 0 Blue 0
2 PM Sun 46 46 S 23 3740 5810 0 Blue 0
3 PM Sun 46 46 S 23 3740 5810 0 Blue 0
4 PM Sun 45 45 S 20 3740 5810 0 Blue 0
5 PM Sun 44 44 S 20 3740 5810 0 Blue 0
6 PM Sun 43 43 S 20 3740 5810 0 Blue 0
7 PM Sun 43 43 S 20 3740 5810 0 Blue 0
8 PM Sun 42 42 S 20 3740 5810 0 Blue 0
9 PM Sun 41 41 S 20 3740 5810 0 Blue 0
10 PM Sun 40 40 SW 13 3740 5810 0 Blue 0
11 PM Sun 40 40 SW 13 3740 5810 0 Blue 0
12 Midnight Mon 40 40 SW 13 3740 5810 0 Blue 0
1 AM Mon 39 39 SW 13 3740 5810 0 Blue 0
2 AM Mon 39 39 SW 13 3740 5810 0 Blue 0
3 AM Mon 39 39 SW 13 3740 5810 0 Blue 0
4 AM Mon 38 38 W 10 3740 5810 0 Blue 0
5 AM Mon 38 38 W 10 3740 5810 0 Blue 0
6 AM Mon 37 37 W 10 3740 5810 0 Blue 0
7 AM Mon 37 37 W 10 3740 5810 0 Blue 0
8 AM Mon 37 37 W 10 3740 5810 0 Blue 0
9 AM Mon 38 38 W 10 3740 5810 0 Blue 0
10 AM Mon 39 39 W 7 3740 5810 0 Blue 0
11 AM Mon 41 41 W 7 3740 5810 0 Blue 0
12 Noon Mon 43 43 W 7 3740 5810 0 Blue 0
1 PM Mon 44 44 W 7 3740 5810 0 Blue 0
2 PM Mon 44 44 W 7 3740 5810 0 Blue 0
3 PM Mon 44 44 W 7 3740 5810 0 Blue 0
4 PM Mon 43 43 W 7 3740 5810 0 Blue 0
5 PM Mon 42 42 W 7 3740 5810 0 Blue 0
6 PM Mon 41 41 W 7 3740 5810 0 Blue 0
7 PM Mon 40 40 W 7 3740 5810 0 Blue 0
8 PM Mon 39 39 W 7 3740 5810 0 Blue 0
9 PM Mon 39 39 W 7 3740 5810 0 Blue 0
10 PM Mon 39 39 W 5 3740 5810 0 Blue 0
11 PM Mon 38 38 W 5 3740 5810 0 Blue 0
12 Midnight Tue 38 38 W 5 3740 5810 0 Blue 0
1 AM Tue 38 38 W 5 3740 5810 0 Blue 0
2 AM Tue 38 38 W 5 3740 5810 0 Blue 0
3 AM Tue 38 38 W 5 3740 5810 0 Blue 0
4 AM Tue 39 39 S 8 3740 5810 0 Blue 0
5 AM Tue 39 39 S 8 3740 5810 0 Blue 0
6 AM Tue 39 39 S 8 3740 5810 0 Blue 0
7 AM Tue 39 39 S 8 3740 5810 0 Blue 0
8 AM Tue 39 39 S 8 3740 5810 0 Blue 0
9 AM Tue 40 40 S 8 3740 5810 0 Blue 0
10 AM Tue 41 41 S 8 3740 5810 0 Blue 0
11 AM Tue 43 43 S 8 3740 5810 0 Blue 0
12 Noon Tue 44 44 S 8 3740 5810 0 Blue 0
1 PM Tue 45 45 S 8 3740 5810 0 Blue 0
2 PM Tue 46 46 S 8 3740 5810 0 Blue 0
3 PM Tue 46 46 S 8 3740 5810 0 Blue 0
4 PM Tue 46 46 SW 8 3740 5810 0 Blue 0
5 PM Tue 45 45 SW 8 3740 5810 0 Blue 0
6 PM Tue 44 44 SW 8 3740 5810 0 Blue 0
7 PM Tue 43 43 SW 8 3740 5810 0 Blue 0
8 PM Tue 43 43 SW 8 3740 5810 0 Blue 0
9 PM Tue 43 43 SW 8 3740 5810 0 Blue 0
10 PM Tue 43 43 W 7 3740 5810 0 Blue 0
11 PM Tue 43 43 W 7 3740 5810 0 Blue 0
12 Midnight Wed 43 43 W 7 3740 5810 0 Blue 0
1 AM Wed 42 42 W 7 3740 5810 0 Blue 0
2 AM Wed 42 42 W 7 3740 5810 0 Blue 0
3 AM Wed 42 42 W 7 3740 5810 0 Blue 0
4 AM Wed 42 42 N 7 3740 5810 0 Blue 0
5 AM Wed 42 42 N 7 3740 5810 0 Blue 0
6 AM Wed 42 42 N 7 3740 5810 0 Blue 0
7 AM Wed 43 43 N 7 3740 5810 0 Blue 0
8 AM Wed 43 43 N 7 3740 5810 0 Blue 0
9 AM Wed 45 45 N 7 3740 5810 0 Blue 0
10 AM Wed 46 46 N 7 3740 5810 0 Blue 0
11 AM Wed 47 47 N 7 3875 5810 0 Blue 0
12 Noon Wed 49 49 N 7 4322 5810 0 Blue 0
1 PM Wed 50 50 N 7 4545 5810 0 Blue 0
2 PM Wed 50 50 N 7 4545 5810 0 Blue 0
3 PM Wed 50 50 N 7 4545 5810 0 Blue 0
4 PM Wed 49 49 S 7 4322 5810 0 Blue 0
5 PM Wed 47 47 S 7 3875 5810 0 Blue 0
6 PM Wed 46 46 S 7 3740 5810 0 Blue 0
7 PM Wed 45 45 S 7 3740 5810 0 Blue 0
8 PM Wed 44 44 S 7 3740 5810 0 Blue 0
9 PM Wed 44 44 S 7 3740 5810 0 Blue 0
10 PM Wed 44 44 SE 10 3740 5810 0 Blue 0
11 PM Wed 44 44 SE 10 3740 5810 0 Blue 0
12 Midnight Thu 44 44 SE 10 3740 5810 0 Blue 0
1 AM Thu 44 44 SE 10 3740 5810 0 Blue 0
2 AM Thu 43 43 SE 10 3740 5810 0 Blue 0
3 AM Thu 43 43 SE 10 3740 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