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

Station:

KOAK

Date/Time:

11 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 Tue 37 37 N 10 4383 5810 0 Blue 0
5 AM Tue 37 37 N 10 4383 5810 0 Blue 0
6 AM Tue 37 37 N 10 4383 5810 0 Blue 0
7 AM Tue 38 38 N 10 4383 5810 0 Blue 0
8 AM Tue 39 39 N 10 4383 5810 0 Blue 0
9 AM Tue 41 41 N 10 5187 5810 0 Blue 0
10 AM Tue 43 43 N 10 5316 5810 0 Blue 2
11 AM Tue 45 45 N 10 5444 5810 0 Blue 4
12 Noon Tue 47 47 N 10 5726 5810 0 Blue 6
1 PM Tue 48 48 NW 12 6226 5810 0 Blue 7
2 PM Tue 48 48 NW 12 6226 5810 0 Blue 7
3 PM Tue 48 48 NW 12 6226 5810 0 Blue 7
4 PM Tue 47 47 NW 8 5726 5810 0 Blue 6
5 PM Tue 45 45 NW 8 5444 5810 0 Blue 4
6 PM Tue 44 44 NW 8 5380 5810 0 Blue 3
7 PM Tue 43 43 NW 12 5316 5810 0 Blue 2
8 PM Tue 42 42 NW 12 5251 5810 0 Blue 1
9 PM Tue 42 42 NW 12 5251 5810 0 Blue 1
10 PM Tue 41 41 NW 12 5187 5810 0 Blue 0
11 PM Tue 41 41 NW 12 5187 5810 0 Blue 0
12 Midnight Wed 40 40 NW 12 4551 5810 0 Blue 0
1 AM Wed 40 40 NW 9 4551 5810 0 Blue 0
2 AM Wed 40 40 NW 9 4551 5810 0 Blue 0
3 AM Wed 39 39 NW 9 4383 5810 0 Blue 0
4 AM Wed 39 39 N 9 4383 5810 0 Blue 0
5 AM Wed 38 38 N 9 4383 5810 0 Blue 0
6 AM Wed 38 38 N 9 4383 5810 0 Blue 0
7 AM Wed 38 38 N 15 4383 5810 0 Blue 0
8 AM Wed 39 39 N 15 4383 5810 0 Blue 0
9 AM Wed 41 41 N 15 5187 5810 0 Blue 0
10 AM Wed 43 44 NE 14 5380 5810 0 Blue 3
11 AM Wed 45 46 NE 14 5538 5810 0 Blue 5
12 Noon Wed 46 47 NE 14 5726 5810 0 Blue 6
1 PM Wed 48 49 NE 10 6713 5810 0 Blue 8
2 PM Wed 48 49 NE 10 6713 5810 0 Blue 8
3 PM Wed 48 48 NE 10 6226 5810 0 Blue 7
4 PM Wed 47 47 N 5 5726 5810 0 Blue 6
5 PM Wed 46 46 N 5 5538 5810 0 Blue 5
6 PM Wed 45 45 N 5 5444 5810 0 Blue 4
7 PM Wed 44 44 N 5 5380 5810 0 Blue 3
8 PM Wed 43 43 N 5 5316 5810 0 Blue 2
9 PM Wed 42 42 N 5 5251 5810 0 Blue 1
10 PM Wed 42 42 NW 5 5251 5810 0 Blue 1
11 PM Wed 42 42 NW 5 5251 5810 0 Blue 1
12 Midnight Thu 42 42 NW 5 5251 5810 0 Blue 1
1 AM Thu 42 42 NW 5 5251 5810 0 Blue 1
2 AM Thu 42 42 NW 5 5251 5810 0 Blue 1
3 AM Thu 41 41 NW 5 5187 5810 0 Blue 0
4 AM Thu 41 41 SW 6 5187 5810 0 Blue 0
5 AM Thu 40 40 SW 6 4551 5810 0 Blue 0
6 AM Thu 40 40 SW 6 4551 5810 0 Blue 0
7 AM Thu 40 40 SW 6 4551 5810 0 Blue 0
8 AM Thu 41 41 SW 6 5187 5810 0 Blue 0
9 AM Thu 42 42 SW 6 5251 5810 0 Blue 1
10 AM Thu 44 44 S 6 5380 5810 0 Blue 3
11 AM Thu 47 48 S 6 6226 5810 0 Blue 7
12 Noon Thu 49 50 S 6 7048 5810 0 Blue 9
1 PM Thu 50 51 S 6 7178 6202 392 Blue 10
2 PM Thu 51 52 S 6 7308 6682 872 Blue 11
3 PM Thu 51 51 S 6 7178 6202 392 Blue 10
4 PM Thu 49 49 S 10 6713 5810 0 Blue 8
5 PM Thu 46 46 S 10 5538 5810 0 Blue 5
6 PM Thu 43 43 S 10 5316 5810 0 Blue 2
7 PM Thu 41 41 S 10 5187 5810 0 Blue 0
8 PM Thu 40 40 S 10 4551 5810 0 Blue 0
9 PM Thu 40 40 S 10 4551 5810 0 Blue 0
10 PM Thu 40 40 S 15 4551 5810 0 Blue 0
11 PM Thu 40 40 S 15 4551 5810 0 Blue 0
12 Midnight Fri 39 39 S 15 4383 5810 0 Blue 0
1 AM Fri 39 39 S 15 4383 5810 0 Blue 0
2 AM Fri 39 39 S 15 4383 5810 0 Blue 0
3 AM Fri 39 39 S 15 4383 5810 0 Blue 0
4 AM Fri 39 39 S 16 4383 5810 0 Blue 0
5 AM Fri 39 39 S 16 4383 5810 0 Blue 0
6 AM Fri 40 40 S 16 4551 5810 0 Blue 0
7 AM Fri 40 40 S 16 4551 5810 0 Blue 0
8 AM Fri 40 40 S 16 4551 5810 0 Blue 0
9 AM Fri 40 40 S 16 4551 5810 0 Blue 0
10 AM Fri 41 41 S 17 5187 5810 0 Blue 0
11 AM Fri 41 41 S 17 5187 5810 0 Blue 0
12 Noon Fri 41 41 S 17 5187 5810 0 Blue 0
1 PM Fri 41 41 S 17 5187 5810 0 Blue 0
2 PM Fri 41 41 S 17 5187 5810 0 Blue 0
3 PM Fri 41 41 S 17 5187 5810 0 Blue 0
4 PM Fri 41 41 W 13 5187 5810 0 Blue 0
5 PM Fri 39 39 W 13 4383 5810 0 Blue 0
6 PM Fri 38 38 W 13 4383 5810 0 Blue 0
7 PM Fri 37 37 W 13 4383 5810 0 Blue 0
8 PM Fri 36 36 W 13 4383 5810 0 Blue 0
9 PM Fri 36 36 W 13 4383 5810 0 Blue 0
10 PM Fri 35 35 E 6 4383 5810 0 Blue 0
11 PM Fri 35 35 E 6 4383 5810 0 Blue 0
12 Midnight Sat 35 35 E 6 4383 5810 0 Blue 0
1 AM Sat 35 35 E 6 4383 5810 0 Blue 0
2 AM Sat 35 35 E 6 4383 5810 0 Blue 0
3 AM Sat 36 36 E 6 4383 5810 0 Blue 0
4 AM Sat 35 35 S 8 4383 5810 0 Blue 0
5 AM Sat 35 35 S 8 4383 5810 0 Blue 0
6 AM Sat 35 35 S 8 4383 5810 0 Blue 0
7 AM Sat 35 35 S 8 4383 5810 0 Blue 0
8 AM Sat 37 37 S 8 4383 5810 0 Blue 0
9 AM Sat 39 39 S 8 4383 5810 0 Blue 0
10 AM Sat 41 41 S 9 5187 5810 0 Blue 0
11 AM Sat 43 43 S 9 5316 5810 0 Blue 2
12 Noon Sat 45 45 S 9 5444 5810 0 Blue 4
1 PM Sat 47 47 S 9 5726 5810 0 Blue 6
2 PM Sat 47 47 S 9 5726 5810 0 Blue 6
3 PM Sat 47 47 S 9 5726 5810 0 Blue 6
4 PM Sat 46 46 S 12 5538 5810 0 Blue 5
5 PM Sat 44 44 S 12 5380 5810 0 Blue 3
6 PM Sat 43 43 S 12 5316 5810 0 Blue 2
7 PM Sat 41 41 S 12 5187 5810 0 Blue 0
8 PM Sat 40 40 S 12 4551 5810 0 Blue 0
9 PM Sat 40 40 S 12 4551 5810 0 Blue 0
10 PM Sat 40 40 S 17 4551 5810 0 Blue 0
11 PM Sat 40 40 S 17 4551 5810 0 Blue 0
12 Midnight Sun 40 40 S 17 4551 5810 0 Blue 0
1 AM Sun 40 40 S 17 4551 5810 0 Blue 0
2 AM Sun 40 40 S 17 4551 5810 0 Blue 0
3 AM Sun 39 39 S 17 4383 5810 0 Blue 0
4 AM Sun 39 39 S 22 4383 5810 0 Blue 0
5 AM Sun 39 39 S 22 4383 5810 0 Blue 0
6 AM Sun 39 39 S 22 4383 5810 0 Blue 0
7 AM Sun 40 40 S 22 4551 5810 0 Blue 0
8 AM Sun 40 40 S 22 4551 5810 0 Blue 0
9 AM Sun 41 41 S 22 5187 5810 0 Blue 0
10 AM Sun 41 41 SW 21 5187 5810 0 Blue 0
11 AM Sun 41 41 SW 21 5187 5810 0 Blue 0
12 Noon Sun 41 41 SW 21 5187 5810 0 Blue 0
1 PM Sun 42 42 SW 21 5251 5810 0 Blue 1
2 PM Sun 42 42 SW 21 5251 5810 0 Blue 1
3 PM Sun 42 42 SW 21 5251 5810 0 Blue 1
4 PM Sun 42 42 W 16 5251 5810 0 Blue 1
5 PM Sun 40 40 W 16 4551 5810 0 Blue 0
6 PM Sun 39 39 W 16 4383 5810 0 Blue 0
7 PM Sun 38 38 W 16 4383 5810 0 Blue 0
8 PM Sun 37 37 W 16 4383 5810 0 Blue 0
9 PM Sun 37 37 W 16 4383 5810 0 Blue 0
10 PM Sun 36 36 W 13 4383 5810 0 Blue 0
11 PM Sun 36 36 W 13 4383 5810 0 Blue 0
12 Midnight Mon 36 36 W 13 4383 5810 0 Blue 0
1 AM Mon 36 36 W 13 4383 5810 0 Blue 0
2 AM Mon 37 37 W 13 4383 5810 0 Blue 0
3 AM Mon 37 37 W 13 4383 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