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

Station:

KOAK

Date/Time:

16 OCT 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 Tue 48 43 N 5 2717 4000 0 Blue 0
6 AM Tue 48 43 N 5 2717 4000 0 Blue 0
7 AM Tue 48 43 N 5 2717 4000 0 Blue 0
8 AM Tue 50 45 N 2 2717 4000 0 Blue 0
9 AM Tue 54 50 N 2 2717 4000 0 Blue 0
10 AM Tue 60 57 N 2 2717 4000 0 Blue 0
11 AM Tue 66 64 W 6 4735 4297 297 Blue 3
12 Noon Tue 69 68 W 6 5807 4920 920 Blue 7
1 PM Tue 70 69 W 6 6910 5171 1171 Blue 8
2 PM Tue 70 69 W 9 6910 5171 1171 Blue 8
3 PM Tue 70 68 W 9 5807 4920 920 Blue 7
4 PM Tue 69 65 W 9 4928 4534 534 Blue 4
5 PM Tue 68 63 N 8 4638 4000 0 Blue 2
6 PM Tue 66 61 N 8 4300 4000 0 Blue 0
7 PM Tue 63 58 N 8 2797 4000 0 Blue 0
8 PM Tue 61 56 N 10 2717 4000 0 Blue 0
9 PM Tue 59 54 N 10 2717 4000 0 Blue 0
10 PM Tue 58 53 N 10 2717 4000 0 Blue 0
11 PM Tue 57 52 NE 6 2717 4000 0 Blue 0
12 Midnight Wed 57 52 NE 6 2717 4000 0 Blue 0
1 AM Wed 56 51 NE 6 2717 4000 0 Blue 0
2 AM Wed 56 51 NE 7 2717 4000 0 Blue 0
3 AM Wed 55 50 NE 7 2717 4000 0 Blue 0
4 AM Wed 54 49 NE 7 2717 4000 0 Blue 0
5 AM Wed 53 48 NE 7 2717 4000 0 Blue 0
6 AM Wed 52 47 NE 7 2717 4000 0 Blue 0
7 AM Wed 52 47 NE 7 2717 4000 0 Blue 0
8 AM Wed 54 49 NE 6 2717 4000 0 Blue 0
9 AM Wed 58 54 NE 6 2717 4000 0 Blue 0
10 AM Wed 63 60 NE 6 3843 4000 0 Blue 0
11 AM Wed 68 66 SW 7 5182 4636 636 Blue 5
12 Noon Wed 70 69 SW 7 6910 5171 1171 Blue 8
1 PM Wed 71 70 SW 7 7881 5436 1436 Blue 9
2 PM Wed 71 70 SW 7 7881 5436 1436 Blue 9
3 PM Wed 71 69 SW 7 6910 5171 1171 Blue 8
4 PM Wed 71 67 SW 7 5449 4732 732 Blue 6
5 PM Wed 69 64 SW 2 4735 4297 297 Blue 3
6 PM Wed 67 62 SW 2 4539 4000 0 Blue 1
7 PM Wed 64 59 SW 2 3327 4000 0 Blue 0
8 PM Wed 61 56 SW 2 2717 4000 0 Blue 0
9 PM Wed 60 55 SW 2 2717 4000 0 Blue 0
10 PM Wed 59 54 SW 2 2717 4000 0 Blue 0
11 PM Wed 58 53 NE 5 2717 4000 0 Blue 0
12 Midnight Thu 57 52 NE 5 2717 4000 0 Blue 0
1 AM Thu 56 51 NE 5 2717 4000 0 Blue 0
2 AM Thu 55 50 NE 5 2717 4000 0 Blue 0
3 AM Thu 55 50 NE 5 2717 4000 0 Blue 0
4 AM Thu 55 50 NE 5 2717 4000 0 Blue 0
5 AM Thu 54 49 N 2 2717 4000 0 Blue 0
6 AM Thu 53 48 N 2 2717 4000 0 Blue 0
7 AM Thu 53 48 N 2 2717 4000 0 Blue 0
8 AM Thu 54 49 N 2 2717 4000 0 Blue 0
9 AM Thu 58 54 N 2 2717 4000 0 Blue 0
10 AM Thu 64 61 N 2 4300 4000 0 Blue 0
11 AM Thu 68 66 W 7 5182 4636 636 Blue 5
12 Noon Thu 71 70 W 7 7881 5436 1436 Blue 9
1 PM Thu 72 71 W 7 8538 5735 1735 Blue 10
2 PM Thu 72 71 W 7 8538 5735 1735 Blue 10
3 PM Thu 72 70 W 7 7881 5436 1436 Blue 9
4 PM Thu 72 68 W 7 5807 4920 920 Blue 7
5 PM Thu 71 66 W 5 5182 4636 636 Blue 5
6 PM Thu 68 63 W 5 4638 4000 0 Blue 2
7 PM Thu 65 60 W 5 3843 4000 0 Blue 0
8 PM Thu 62 57 W 5 2717 4000 0 Blue 0
9 PM Thu 60 55 W 5 2717 4000 0 Blue 0
10 PM Thu 58 53 W 5 2717 4000 0 Blue 0
11 PM Thu 57 52 W 6 2717 4000 0 Blue 0
12 Midnight Fri 56 51 W 6 2717 4000 0 Blue 0
1 AM Fri 56 51 W 6 2717 4000 0 Blue 0
2 AM Fri 55 50 W 6 2717 4000 0 Blue 0
3 AM Fri 55 50 W 6 2717 4000 0 Blue 0
4 AM Fri 55 50 W 6 2717 4000 0 Blue 0
5 AM Fri 54 49 N 6 2717 4000 0 Blue 0
6 AM Fri 53 48 N 6 2717 4000 0 Blue 0
7 AM Fri 52 47 N 6 2717 4000 0 Blue 0
8 AM Fri 53 48 N 6 2717 4000 0 Blue 0
9 AM Fri 58 54 N 6 2717 4000 0 Blue 0
10 AM Fri 65 62 N 6 4539 4000 0 Blue 1
11 AM Fri 71 69 SW 6 6910 5171 1171 Blue 8
12 Noon Fri 74 73 SW 6 9038 7764 3764 Blue 12
1 PM Fri 76 75 SW 6 9778 8749 4749 Blue 14
2 PM Fri 76 75 SW 6 9778 8749 4749 Blue 14
3 PM Fri 76 74 SW 6 9286 8500 4500 Blue 13
4 PM Fri 75 71 SW 6 8538 5735 1735 Blue 10
5 PM Fri 74 69 NW 5 6910 5171 1171 Blue 8
6 PM Fri 71 66 NW 5 5182 4636 636 Blue 5
7 PM Fri 67 62 NW 5 4539 4000 0 Blue 1
8 PM Fri 64 59 NW 5 3327 4000 0 Blue 0
9 PM Fri 62 57 NW 5 2717 4000 0 Blue 0
10 PM Fri 60 55 NW 5 2717 4000 0 Blue 0
11 PM Fri 59 54 N 7 2717 4000 0 Blue 0
12 Midnight Sat 58 53 N 7 2717 4000 0 Blue 0
1 AM Sat 57 52 N 7 2717 4000 0 Blue 0
2 AM Sat 56 51 N 7 2717 4000 0 Blue 0
3 AM Sat 55 50 N 7 2717 4000 0 Blue 0
4 AM Sat 55 50 N 7 2717 4000 0 Blue 0
5 AM Sat 54 49 N 6 2717 4000 0 Blue 0
6 AM Sat 52 47 N 6 2717 4000 0 Blue 0
7 AM Sat 52 47 N 6 2717 4000 0 Blue 0
8 AM Sat 54 49 N 6 2717 4000 0 Blue 0
9 AM Sat 58 54 N 6 2717 4000 0 Blue 0
10 AM Sat 64 61 N 6 4300 4000 0 Blue 0
11 AM Sat 70 68 SW 6 5807 4920 920 Blue 7
12 Noon Sat 73 72 SW 6 8788 6812 2812 Blue 11
1 PM Sat 74 73 SW 6 9038 7764 3764 Blue 12
2 PM Sat 75 74 SW 6 9286 8500 4500 Blue 13
3 PM Sat 75 73 SW 6 9038 7764 3764 Blue 12
4 PM Sat 75 71 SW 6 8538 5735 1735 Blue 10
5 PM Sat 73 68 NW 5 5807 4920 920 Blue 7
6 PM Sat 70 65 NW 5 4928 4534 534 Blue 4
7 PM Sat 66 61 NW 5 4300 4000 0 Blue 0
8 PM Sat 63 58 NW 5 2797 4000 0 Blue 0
9 PM Sat 62 57 NW 5 2717 4000 0 Blue 0
10 PM Sat 61 56 NW 5 2717 4000 0 Blue 0
11 PM Sat 60 55 N 6 2717 4000 0 Blue 0
12 Midnight Sun 60 55 N 6 2717 4000 0 Blue 0
1 AM Sun 59 54 N 6 2717 4000 0 Blue 0
2 AM Sun 58 53 N 6 2717 4000 0 Blue 0
3 AM Sun 57 52 N 6 2717 4000 0 Blue 0
4 AM Sun 56 51 N 6 2717 4000 0 Blue 0
5 AM Sun 56 51 NE 5 2717 4000 0 Blue 0
6 AM Sun 55 50 NE 5 2717 4000 0 Blue 0
7 AM Sun 55 50 NE 5 2717 4000 0 Blue 0
8 AM Sun 57 52 NE 5 2717 4000 0 Blue 0
9 AM Sun 60 56 NE 5 2717 4000 0 Blue 0
10 AM Sun 65 62 NE 5 4539 4000 0 Blue 1
11 AM Sun 69 67 SW 6 5449 4732 732 Blue 6
12 Noon Sun 72 71 SW 6 8538 5735 1735 Blue 10
1 PM Sun 73 72 SW 6 8788 6812 2812 Blue 11
2 PM Sun 74 73 SW 6 9038 7764 3764 Blue 12
3 PM Sun 74 72 SW 6 8788 6812 2812 Blue 11
4 PM Sun 73 69 SW 6 6910 5171 1171 Blue 8
5 PM Sun 72 67 SW 7 5449 4732 732 Blue 6
6 PM Sun 69 64 SW 7 4735 4297 297 Blue 3
7 PM Sun 66 61 SW 7 4300 4000 0 Blue 0
8 PM Sun 63 58 SW 7 2797 4000 0 Blue 0
9 PM Sun 61 56 SW 7 2717 4000 0 Blue 0
10 PM Sun 61 56 SW 7 2717 4000 0 Blue 0
11 PM Sun 60 55 NE 6 2717 4000 0 Blue 0
12 Midnight Mon 59 54 NE 6 2717 4000 0 Blue 0
1 AM Mon 59 54 NE 6 2717 4000 0 Blue 0
2 AM Mon 58 53 NE 6 2717 4000 0 Blue 0
3 AM Mon 58 53 NE 6 2717 4000 0 Blue 0
4 AM Mon 57 52 NE 6 2717 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 ac_soaring@yahoo.com