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

Station:

KOAK

Date/Time:

22 SEP 2017

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 Fri 46 41 NE 7 3848 4000 0 Blue 0
6 AM Fri 45 40 NE 7 3848 4000 0 Blue 0
7 AM Fri 46 41 NE 7 3848 4000 0 Blue 0
8 AM Fri 47 42 NE 3 3848 4000 0 Blue 0
9 AM Fri 51 47 NE 3 3954 4000 0 Blue 0
10 AM Fri 54 51 NE 3 5522 4327 327 Blue 2
11 AM Fri 58 57 W 7 9969 7271 3271 Blue 8
12 Noon Fri 60 60 W 7 11413 9377 5377 Blue 11
1 PM Fri 61 61 W 7 11830 10652 6652 Blue 12
2 PM Fri 62 61 W 6 11830 10652 6652 Blue 12
3 PM Fri 63 61 W 6 11830 10652 6652 Blue 12
4 PM Fri 63 60 W 6 11413 9377 5377 Blue 11
5 PM Fri 62 58 NW 7 10731 8022 4022 Blue 9
6 PM Fri 61 56 NW 7 8436 6463 2463 Blue 7
7 PM Fri 59 54 NW 7 7361 5492 1492 Blue 5
8 PM Fri 56 51 N 6 5522 4327 327 Blue 2
9 PM Fri 55 50 N 6 5320 4000 0 Blue 1
10 PM Fri 54 49 N 6 4716 4000 0 Blue 0
11 PM Fri 53 48 NE 7 4333 4000 0 Blue 0
12 Midnight Sat 52 47 NE 7 3954 4000 0 Blue 0
1 AM Sat 52 47 NE 7 3954 4000 0 Blue 0
2 AM Sat 51 46 NE 6 3848 4000 0 Blue 0
3 AM Sat 49 44 NE 6 3848 4000 0 Blue 0
4 AM Sat 48 43 NE 6 3848 4000 0 Blue 0
5 AM Sat 47 42 NE 7 3848 4000 0 Blue 0
6 AM Sat 47 42 NE 7 3848 4000 0 Blue 0
7 AM Sat 48 43 NE 7 3848 4000 0 Blue 0
8 AM Sat 50 45 N 3 3848 4000 0 Blue 0
9 AM Sat 54 50 N 3 5320 4000 0 Blue 1
10 AM Sat 58 55 N 3 8098 5992 1992 Blue 6
11 AM Sat 61 60 W 5 11413 9377 5377 Blue 11
12 Noon Sat 63 63 W 5 12802 11327 7327 Blue 14
1 PM Sat 64 64 W 5 13082 11695 7695 Blue 15
2 PM Sat 65 65 W 7 13286 12183 8183 Blue 16
3 PM Sat 66 65 W 7 13286 12183 8183 Blue 16
4 PM Sat 67 64 W 7 13082 11695 7695 Blue 15
5 PM Sat 66 62 NW 6 12323 10991 6991 Blue 13
6 PM Sat 64 59 NW 6 11074 8385 4385 Blue 10
7 PM Sat 60 55 NW 6 8098 5992 1992 Blue 6
8 PM Sat 58 53 NW 6 6537 5312 1312 Blue 4
9 PM Sat 56 51 NW 6 5522 4327 327 Blue 2
10 PM Sat 56 51 NW 6 5522 4327 327 Blue 2
11 PM Sat 55 50 NE 7 5320 4000 0 Blue 1
12 Midnight Sun 54 49 NE 7 4716 4000 0 Blue 0
1 AM Sun 53 48 NE 7 4333 4000 0 Blue 0
2 AM Sun 52 47 NE 7 3954 4000 0 Blue 0
3 AM Sun 51 46 NE 7 3848 4000 0 Blue 0
4 AM Sun 51 46 NE 7 3848 4000 0 Blue 0
5 AM Sun 51 46 NE 6 3848 4000 0 Blue 0
6 AM Sun 51 46 NE 6 3848 4000 0 Blue 0
7 AM Sun 52 47 NE 6 3954 4000 0 Blue 0
8 AM Sun 54 49 NE 6 4716 4000 0 Blue 0
9 AM Sun 57 53 NE 6 6537 5312 1312 Blue 4
10 AM Sun 61 59 NE 6 11074 8385 4385 Blue 10
11 AM Sun 64 63 SW 5 12802 11327 7327 Blue 14
12 Noon Sun 67 67 SW 5 13572 13018 9018 Blue 18
1 PM Sun 68 69 SW 5 14060 13394 9394 Blue 20
2 PM Sun 69 69 SW 5 14060 13394 9394 Blue 20
3 PM Sun 70 69 SW 5 14060 13394 9394 Blue 20
4 PM Sun 70 68 SW 5 13817 13220 9220 Blue 19
5 PM Sun 69 65 NW 5 13286 12183 8183 Blue 16
6 PM Sun 66 61 NW 5 11830 10652 6652 Blue 12
7 PM Sun 63 58 NW 5 10731 8022 4022 Blue 9
8 PM Sun 60 55 NW 5 8098 5992 1992 Blue 6
9 PM Sun 58 53 NW 5 6537 5312 1312 Blue 4
10 PM Sun 58 53 NW 5 6537 5312 1312 Blue 4
11 PM Sun 57 52 NE 6 6026 4704 704 Blue 3
12 Midnight Mon 57 52 NE 6 6026 4704 704 Blue 3
1 AM Mon 57 52 NE 6 6026 4704 704 Blue 3
2 AM Mon 56 51 NE 6 5522 4327 327 Blue 2
3 AM Mon 56 51 NE 6 5522 4327 327 Blue 2
4 AM Mon 56 51 NE 6 5522 4327 327 Blue 2
5 AM Mon 55 50 S 6 5320 4000 0 Blue 1
6 AM Mon 55 50 S 6 5320 4000 0 Blue 1
7 AM Mon 55 50 S 6 5320 4000 0 Blue 1
8 AM Mon 57 52 S 6 6026 4704 704 Blue 3
9 AM Mon 61 57 S 6 9969 7271 3271 Blue 8
10 AM Mon 65 63 S 6 12802 11327 7327 Blue 14
11 AM Mon 69 68 SW 5 13817 13220 9220 Blue 19
12 Noon Mon 71 71 SW 5 14543 13733 9733 Blue 22
1 PM Mon 72 72 SW 5 14751 13974 9974 Blue 23
2 PM Mon 73 73 SW 5 14930 14214 10214 Blue 24
3 PM Mon 74 73 SW 5 14930 14214 10214 Blue 24
4 PM Mon 74 71 SW 5 14543 13733 9733 Blue 22
5 PM Mon 73 69 NW 6 14060 13394 9394 Blue 20
6 PM Mon 70 65 NW 6 13286 12183 8183 Blue 16
7 PM Mon 66 61 NW 6 11830 10652 6652 Blue 12
8 PM Mon 63 58 NW 6 10731 8022 4022 Blue 9
9 PM Mon 60 55 NW 6 8098 5992 1992 Blue 6
10 PM Mon 59 54 NW 6 7361 5492 1492 Blue 5
11 PM Mon 59 54 NE 6 7361 5492 1492 Blue 5
12 Midnight Tue 58 53 NE 6 6537 5312 1312 Blue 4
1 AM Tue 58 53 NE 6 6537 5312 1312 Blue 4
2 AM Tue 58 53 NE 6 6537 5312 1312 Blue 4
3 AM Tue 57 52 NE 6 6026 4704 704 Blue 3
4 AM Tue 57 52 NE 6 6026 4704 704 Blue 3
5 AM Tue 56 51 S 5 5522 4327 327 Blue 2
6 AM Tue 56 51 S 5 5522 4327 327 Blue 2
7 AM Tue 57 52 S 5 6026 4704 704 Blue 3
8 AM Tue 59 54 S 5 7361 5492 1492 Blue 5
9 AM Tue 62 58 S 5 10731 8022 4022 Blue 9
10 AM Tue 67 65 S 5 13286 12183 8183 Blue 16
11 AM Tue 71 70 SW 5 14302 13520 9520 Blue 21
12 Noon Tue 74 74 SW 5 15110 14453 10453 Blue 25
1 PM Tue 75 76 SW 5 15467 14861 10861 Blue 27
2 PM Tue 76 76 SW 5 15467 14861 10861 Blue 27
3 PM Tue 76 75 SW 5 15289 14682 10682 Blue 26
4 PM Tue 76 74 SW 5 15110 14453 10453 Blue 25
5 PM Tue 75 71 NW 5 14543 13733 9733 Blue 22
6 PM Tue 72 67 NW 5 13572 13018 9018 Blue 18
7 PM Tue 69 64 NW 5 13082 11695 7695 Blue 15
8 PM Tue 67 62 NW 5 12323 10991 6991 Blue 13
9 PM Tue 65 60 NW 5 11413 9377 5377 Blue 11
10 PM Tue 64 59 NW 5 11074 8385 4385 Blue 10
11 PM Tue 64 59 NE 5 11074 8385 4385 Blue 10
12 Midnight Wed 64 59 NE 5 11074 8385 4385 Blue 10
1 AM Wed 63 58 NE 5 10731 8022 4022 Blue 9
2 AM Wed 63 58 NE 5 10731 8022 4022 Blue 9
3 AM Wed 62 57 NE 5 9969 7271 3271 Blue 8
4 AM Wed 61 56 NE 5 8436 6463 2463 Blue 7
5 AM Wed 61 56 E 5 8436 6463 2463 Blue 7
6 AM Wed 61 56 E 5 8436 6463 2463 Blue 7
7 AM Wed 62 57 E 5 9969 7271 3271 Blue 8
8 AM Wed 64 59 E 5 11074 8385 4385 Blue 10
9 AM Wed 68 64 E 5 13082 11695 7695 Blue 15
10 AM Wed 72 70 E 5 14302 13520 9520 Blue 21
11 AM Wed 75 74 SW 5 15110 14453 10453 Blue 25
12 Noon Wed 78 78 SW 5 15773 15217 11217 Blue 29
1 PM Wed 79 80 SW 5 16095 15572 11572 Blue 31
2 PM Wed 80 80 SW 5 16095 15572 11572 Blue 31
3 PM Wed 80 79 SW 5 15909 15394 11394 Blue 30
4 PM Wed 80 77 SW 5 15641 15039 11039 Blue 28
5 PM Wed 78 74 S 3 15110 14453 10453 Blue 25
6 PM Wed 76 71 S 3 14543 13733 9733 Blue 22
7 PM Wed 73 68 S 3 13817 13220 9220 Blue 19
8 PM Wed 70 65 S 3 13286 12183 8183 Blue 16
9 PM Wed 69 64 S 3 13082 11695 7695 Blue 15
10 PM Wed 69 64 S 3 13082 11695 7695 Blue 15
11 PM Wed 68 63 NE 5 12802 11327 7327 Blue 14
12 Midnight Thu 67 62 NE 5 12323 10991 6991 Blue 13
1 AM Thu 66 61 NE 5 11830 10652 6652 Blue 12
2 AM Thu 65 60 NE 5 11413 9377 5377 Blue 11
3 AM Thu 64 59 NE 5 11074 8385 4385 Blue 10
4 AM Thu 64 59 NE 5 11074 8385 4385 Blue 10

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