Detailed Predictions for: Tollhouse
Launch Altitude (f): 4000
LZ Altitude (f): 1900
Sounding

Station:

KOAK

Date/Time:

26 NOV 2020

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 Thu 39 34 SE 7 3586 4000 0 Blue 0
5 AM Thu 38 33 SE 7 3586 4000 0 Blue 0
6 AM Thu 37 32 SE 8 3586 4000 0 Blue 0
7 AM Thu 35 30 SE 8 3586 4000 0 Blue 0
8 AM Thu 37 32 SE 7 3586 4000 0 Blue 0
9 AM Thu 41 36 SE 6 3586 4000 0 Blue 0
10 AM Thu 42 38 SE 7 3586 4000 0 Blue 0
11 AM Thu 43 40 S 7 3586 4000 0 Blue 0
12 Noon Thu 44 41 SW 6 3883 4000 0 Blue 0
1 PM Thu 44 41 SW 5 3883 4000 0 Blue 0
2 PM Thu 45 41 SW 3 3883 4000 0 Blue 0
3 PM Thu 45 40 SW 5 3586 4000 0 Blue 0
4 PM Thu 44 39 SW 2 3586 4000 0 Blue 0
5 PM Thu 43 38 SE 1 3586 4000 0 Blue 0
6 PM Thu 41 36 E 7 3586 4000 0 Blue 0
7 PM Thu 39 34 E 6 3586 4000 0 Blue 0
8 PM Thu 39 34 E 2 3586 4000 0 Blue 0
9 PM Thu 39 34 SE 6 3586 4000 0 Blue 0
10 PM Thu 39 34 E 9 3586 4000 0 Blue 0
11 PM Thu 38 33 E 6 3586 4000 0 Blue 0
12 Midnight Fri 38 33 SE 5 3586 4000 0 Blue 0
1 AM Fri 38 33 E 9 3586 4000 0 Blue 0
2 AM Fri 38 33 E 9 3586 4000 0 Blue 0
3 AM Fri 39 34 E 6 3586 4000 0 Blue 0
4 AM Fri 38 33 E 3 3586 4000 0 Blue 0
5 AM Fri 37 32 N 1 3586 4000 0 Blue 0
6 AM Fri 37 32 N 3 3586 4000 0 Blue 0
7 AM Fri 36 31 N 3 3586 4000 0 Blue 0
8 AM Fri 39 34 N 5 3586 4000 0 Blue 0
9 AM Fri 44 39 N 3 3586 4000 0 Blue 0
10 AM Fri 46 42 S 2 4277 4000 0 Blue 0
11 AM Fri 47 44 S 2 4942 4000 0 Blue 1
12 Noon Fri 49 46 S 2 5912 4656 656 Blue 3
1 PM Fri 50 47 SW 2 6572 4935 935 Blue 4
2 PM Fri 50 46 SW 2 5912 4656 656 Blue 3
3 PM Fri 49 44 SW 2 4942 4000 0 Blue 1
4 PM Fri 48 43 W 2 4666 4000 0 Blue 0
5 PM Fri 46 41 W 2 3883 4000 0 Blue 0
6 PM Fri 44 39 W 2 3586 4000 0 Blue 0
7 PM Fri 43 38 NE 2 3586 4000 0 Blue 0
8 PM Fri 43 38 NE 2 3586 4000 0 Blue 0
9 PM Fri 43 38 NE 2 3586 4000 0 Blue 0
10 PM Fri 43 38 E 2 3586 4000 0 Blue 0
11 PM Fri 43 38 E 2 3586 4000 0 Blue 0
12 Midnight Sat 42 37 E 2 3586 4000 0 Blue 0
1 AM Sat 42 37 NE 2 3586 4000 0 Blue 0
2 AM Sat 42 37 NE 2 3586 4000 0 Blue 0
3 AM Sat 42 37 NE 2 3586 4000 0 Blue 0
4 AM Sat 42 37 NE 2 3586 4000 0 Blue 0
5 AM Sat 41 36 NE 2 3586 4000 0 Blue 0
6 AM Sat 41 36 NE 2 3586 4000 0 Blue 0
7 AM Sat 41 36 NE 2 3586 4000 0 Blue 0
8 AM Sat 44 39 NE 2 3586 4000 0 Blue 0
9 AM Sat 47 42 NE 2 4277 4000 0 Blue 0
10 AM Sat 50 46 SW 2 5912 4656 656 Blue 3
11 AM Sat 52 49 SW 2 7239 5877 1877 Blue 6
12 Noon Sat 53 50 SW 2 7422 6507 2507 Blue 6
1 PM Sat 53 50 W 3 7422 6507 2507 Blue 6
2 PM Sat 53 49 W 3 7239 5877 1877 Blue 6
3 PM Sat 52 47 W 3 6572 4935 935 Blue 4
4 PM Sat 51 46 W 2 5912 4656 656 Blue 3
5 PM Sat 49 44 W 2 4942 4000 0 Blue 1
6 PM Sat 47 42 W 2 4277 4000 0 Blue 0
7 PM Sat 45 40 NE 1 3586 4000 0 Blue 0
8 PM Sat 45 40 NE 1 3586 4000 0 Blue 0
9 PM Sat 45 40 NE 1 3586 4000 0 Blue 0
10 PM Sat 45 40 NE 2 3586 4000 0 Blue 0
11 PM Sat 45 40 NE 2 3586 4000 0 Blue 0
12 Midnight Sun 44 39 NE 2 3586 4000 0 Blue 0
1 AM Sun 44 39 NE 2 3586 4000 0 Blue 0
2 AM Sun 44 39 NE 2 3586 4000 0 Blue 0
3 AM Sun 44 39 NE 2 3586 4000 0 Blue 0
4 AM Sun 44 39 NE 2 3586 4000 0 Blue 0
5 AM Sun 43 38 NE 2 3586 4000 0 Blue 0
6 AM Sun 42 37 NE 2 3586 4000 0 Blue 0
7 AM Sun 42 37 NE 2 3586 4000 0 Blue 0
8 AM Sun 44 39 NE 2 3586 4000 0 Blue 0
9 AM Sun 48 43 NE 2 4666 4000 0 Blue 0
10 AM Sun 51 47 S 3 6572 4935 935 Blue 4
11 AM Sun 53 50 S 3 7422 6507 2507 Blue 6
12 Noon Sun 54 51 S 3 7512 6976 2976 Blue 7
1 PM Sun 54 50 SW 3 7422 6507 2507 Blue 6
2 PM Sun 54 50 SW 3 7422 6507 2507 Blue 6
3 PM Sun 54 49 SW 3 7239 5877 1877 Blue 6
4 PM Sun 53 48 W 2 7001 5357 1357 Blue 5
5 PM Sun 51 46 W 2 5912 4656 656 Blue 3
6 PM Sun 48 43 W 2 4666 4000 0 Blue 0
7 PM Sun 46 41 NE 2 3883 4000 0 Blue 0
8 PM Sun 45 40 NE 2 3586 4000 0 Blue 0
9 PM Sun 45 40 NE 2 3586 4000 0 Blue 0
10 PM Sun 45 40 NE 2 3586 4000 0 Blue 0
11 PM Sun 45 40 NE 2 3586 4000 0 Blue 0
12 Midnight Mon 45 40 NE 2 3586 4000 0 Blue 0
1 AM Mon 45 40 NE 2 3586 4000 0 Blue 0
2 AM Mon 45 40 NE 2 3586 4000 0 Blue 0
3 AM Mon 45 40 NE 2 3586 4000 0 Blue 0
4 AM Mon 45 40 NE 2 3586 4000 0 Blue 0
5 AM Mon 44 39 NE 2 3586 4000 0 Blue 0
6 AM Mon 43 38 NE 2 3586 4000 0 Blue 0
7 AM Mon 43 38 NE 2 3586 4000 0 Blue 0
8 AM Mon 45 40 NE 2 3586 4000 0 Blue 0
9 AM Mon 47 42 NE 2 4277 4000 0 Blue 0
10 AM Mon 50 46 W 3 5912 4656 656 Blue 3
11 AM Mon 52 48 W 3 7001 5357 1357 Blue 5
12 Noon Mon 53 49 W 3 7239 5877 1877 Blue 6
1 PM Mon 53 49 W 5 7239 5877 1877 Blue 6
2 PM Mon 53 49 W 5 7239 5877 1877 Blue 6
3 PM Mon 52 47 W 5 6572 4935 935 Blue 4
4 PM Mon 51 46 W 2 5912 4656 656 Blue 3
5 PM Mon 49 44 W 2 4942 4000 0 Blue 1
6 PM Mon 47 42 W 2 4277 4000 0 Blue 0
7 PM Mon 45 40 NE 1 3586 4000 0 Blue 0
8 PM Mon 44 39 NE 1 3586 4000 0 Blue 0
9 PM Mon 44 39 NE 1 3586 4000 0 Blue 0
10 PM Mon 44 39 NE 1 3586 4000 0 Blue 0
11 PM Mon 44 39 NE 1 3586 4000 0 Blue 0
12 Midnight Tue 44 39 NE 1 3586 4000 0 Blue 0
1 AM Tue 44 39 NE 1 3586 4000 0 Blue 0
2 AM Tue 44 39 NE 1 3586 4000 0 Blue 0
3 AM Tue 44 39 NE 1 3586 4000 0 Blue 0
4 AM Tue 43 38 NE 1 3586 4000 0 Blue 0
5 AM Tue 42 37 NE 1 3586 4000 0 Blue 0
6 AM Tue 40 35 NE 1 3586 4000 0 Blue 0
7 AM Tue 40 35 NE 1 3586 4000 0 Blue 0
8 AM Tue 42 37 NE 1 3586 4000 0 Blue 0
9 AM Tue 44 39 NE 1 3586 4000 0 Blue 0
10 AM Tue 47 43 S 2 4666 4000 0 Blue 0
11 AM Tue 48 45 S 2 5384 4272 272 Blue 2
12 Noon Tue 49 46 S 2 5912 4656 656 Blue 3
1 PM Tue 50 47 SW 3 6572 4935 935 Blue 4
2 PM Tue 51 47 SW 3 6572 4935 935 Blue 4
3 PM Tue 51 46 SW 3 5912 4656 656 Blue 3
4 PM Tue 50 45 W 2 5384 4272 272 Blue 2
5 PM Tue 48 43 W 2 4666 4000 0 Blue 0
6 PM Tue 46 41 W 2 3883 4000 0 Blue 0
7 PM Tue 44 39 NE 2 3586 4000 0 Blue 0
8 PM Tue 44 39 NE 2 3586 4000 0 Blue 0
9 PM Tue 44 39 NE 2 3586 4000 0 Blue 0
10 PM Tue 44 39 NE 2 3586 4000 0 Blue 0
11 PM Tue 44 39 NE 2 3586 4000 0 Blue 0
12 Midnight Wed 44 39 NE 2 3586 4000 0 Blue 0
1 AM Wed 44 39 NE 2 3586 4000 0 Blue 0
2 AM Wed 44 39 NE 2 3586 4000 0 Blue 0
3 AM Wed 44 39 NE 2 3586 4000 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 [email protected]