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

Station:

KOAK

Date/Time:

18 OCT 2019

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 49 44 NE 5 3615 4000 0 Blue 0
6 AM Fri 46 41 NE 2 3615 4000 0 Blue 0
7 AM Fri 45 40 NE 2 3615 4000 0 Blue 0
8 AM Fri 46 41 NE 2 3615 4000 0 Blue 0
9 AM Fri 52 47 SE 3 3615 4000 0 Blue 0
10 AM Fri 57 54 SE 5 4344 4000 0 Blue 0
11 AM Fri 59 56 SW 5 5383 4000 0 Blue 2
12 Noon Fri 60 59 SW 6 6810 5359 1359 Blue 4
1 PM Fri 61 60 SW 6 7182 5841 1841 Blue 5
2 PM Fri 62 60 W 7 7182 5841 1841 Blue 5
3 PM Fri 63 60 W 6 7182 5841 1841 Blue 5
4 PM Fri 63 59 W 6 6810 5359 1359 Blue 4
5 PM Fri 62 57 W 7 5872 4338 338 Blue 2
6 PM Fri 60 55 W 6 4869 4000 0 Blue 1
7 PM Fri 56 51 N 5 3615 4000 0 Blue 0
8 PM Fri 54 49 NE 5 3615 4000 0 Blue 0
9 PM Fri 52 47 NE 3 3615 4000 0 Blue 0
10 PM Fri 52 47 NE 2 3615 4000 0 Blue 0
11 PM Fri 51 46 NE 5 3615 4000 0 Blue 0
12 Midnight Sat 50 45 NE 2 3615 4000 0 Blue 0
1 AM Sat 49 44 NE 2 3615 4000 0 Blue 0
2 AM Sat 49 44 NE 6 3615 4000 0 Blue 0
3 AM Sat 50 45 NE 2 3615 4000 0 Blue 0
4 AM Sat 49 44 NE 2 3615 4000 0 Blue 0
5 AM Sat 48 43 NE 6 3615 4000 0 Blue 0
6 AM Sat 48 43 NE 2 3615 4000 0 Blue 0
7 AM Sat 47 42 NE 2 3615 4000 0 Blue 0
8 AM Sat 48 43 NE 3 3615 4000 0 Blue 0
9 AM Sat 54 50 W 2 3615 4000 0 Blue 0
10 AM Sat 59 56 SW 3 5383 4000 0 Blue 2
11 AM Sat 61 59 SW 5 6810 5359 1359 Blue 4
12 Noon Sat 62 61 SW 5 7435 6309 2309 Blue 6
1 PM Sat 63 62 SW 5 7688 6766 2766 Blue 7
2 PM Sat 64 62 W 8 7688 6766 2766 Blue 7
3 PM Sat 65 62 W 8 7688 6766 2766 Blue 7
4 PM Sat 65 61 W 8 7435 6309 2309 Blue 6
5 PM Sat 64 59 W 8 6810 5359 1359 Blue 4
6 PM Sat 62 57 W 8 5872 4338 338 Blue 2
7 PM Sat 58 53 W 8 3919 4000 0 Blue 0
8 PM Sat 55 50 NW 6 3615 4000 0 Blue 0
9 PM Sat 54 49 NW 6 3615 4000 0 Blue 0
10 PM Sat 53 48 NW 6 3615 4000 0 Blue 0
11 PM Sat 52 47 NE 2 3615 4000 0 Blue 0
12 Midnight Sun 52 47 NE 2 3615 4000 0 Blue 0
1 AM Sun 50 45 NE 2 3615 4000 0 Blue 0
2 AM Sun 50 45 NE 3 3615 4000 0 Blue 0
3 AM Sun 51 46 NE 3 3615 4000 0 Blue 0
4 AM Sun 50 45 NE 3 3615 4000 0 Blue 0
5 AM Sun 49 44 NE 3 3615 4000 0 Blue 0
6 AM Sun 49 44 NE 3 3615 4000 0 Blue 0
7 AM Sun 48 43 NE 3 3615 4000 0 Blue 0
8 AM Sun 49 44 E 2 3615 4000 0 Blue 0
9 AM Sun 55 51 E 2 3615 4000 0 Blue 0
10 AM Sun 60 57 E 2 5872 4338 338 Blue 2
11 AM Sun 62 60 W 6 7182 5841 1841 Blue 5
12 Noon Sun 63 62 W 6 7688 6766 2766 Blue 7
1 PM Sun 64 63 W 6 7938 7155 3155 Blue 8
2 PM Sun 65 64 W 7 8188 7406 3406 Blue 9
3 PM Sun 66 64 W 7 8188 7406 3406 Blue 9
4 PM Sun 66 62 W 7 7688 6766 2766 Blue 7
5 PM Sun 65 60 W 7 7182 5841 1841 Blue 5
6 PM Sun 63 58 W 7 6347 4849 849 Blue 3
7 PM Sun 60 55 W 7 4869 4000 0 Blue 1
8 PM Sun 57 52 NE 5 3615 4000 0 Blue 0
9 PM Sun 56 51 NE 5 3615 4000 0 Blue 0
10 PM Sun 55 50 NE 5 3615 4000 0 Blue 0
11 PM Sun 55 50 NE 2 3615 4000 0 Blue 0
12 Midnight Mon 54 49 NE 2 3615 4000 0 Blue 0
1 AM Mon 53 48 NE 2 3615 4000 0 Blue 0
2 AM Mon 53 48 NE 3 3615 4000 0 Blue 0
3 AM Mon 54 49 NE 3 3615 4000 0 Blue 0
4 AM Mon 53 48 NE 3 3615 4000 0 Blue 0
5 AM Mon 52 47 NE 3 3615 4000 0 Blue 0
6 AM Mon 52 47 NE 3 3615 4000 0 Blue 0
7 AM Mon 51 46 NE 3 3615 4000 0 Blue 0
8 AM Mon 52 47 NE 2 3615 4000 0 Blue 0
9 AM Mon 60 56 NE 2 5383 4000 0 Blue 2
10 AM Mon 65 62 NE 2 7688 6766 2766 Blue 7
11 AM Mon 67 65 SW 3 8437 7656 3656 Blue 10
12 Noon Mon 69 68 SW 3 9206 8400 4400 Blue 13
1 PM Mon 70 69 SW 3 9598 8645 4645 Blue 14
2 PM Mon 71 70 SW 6 10158 8869 4869 Blue 15
3 PM Mon 72 70 SW 6 10158 8869 4869 Blue 15
4 PM Mon 72 68 SW 6 9206 8400 4400 Blue 13
5 PM Mon 71 66 W 5 8684 7905 3905 Blue 11
6 PM Mon 69 64 W 5 8188 7406 3406 Blue 9
7 PM Mon 65 60 W 5 7182 5841 1841 Blue 5
8 PM Mon 62 57 NE 3 5872 4338 338 Blue 2
9 PM Mon 61 56 NE 3 5383 4000 0 Blue 2
10 PM Mon 60 55 NE 3 4869 4000 0 Blue 1
11 PM Mon 59 54 NE 2 4344 4000 0 Blue 0
12 Midnight Tue 59 54 NE 2 4344 4000 0 Blue 0
1 AM Tue 57 52 NE 2 3615 4000 0 Blue 0
2 AM Tue 57 52 NE 3 3615 4000 0 Blue 0
3 AM Tue 58 53 NE 3 3919 4000 0 Blue 0
4 AM Tue 57 52 NE 3 3615 4000 0 Blue 0
5 AM Tue 56 51 NE 3 3615 4000 0 Blue 0
6 AM Tue 56 51 NE 3 3615 4000 0 Blue 0
7 AM Tue 55 50 NE 3 3615 4000 0 Blue 0
8 AM Tue 56 51 NE 3 3615 4000 0 Blue 0
9 AM Tue 64 59 NE 3 6810 5359 1359 Blue 4
10 AM Tue 69 66 NE 3 8684 7905 3905 Blue 11
11 AM Tue 72 70 SW 3 10158 8869 4869 Blue 15
12 Noon Tue 74 73 SW 3 12095 10041 6041 Blue 18
1 PM Tue 75 74 SW 3 12532 10686 6686 Blue 19
2 PM Tue 76 75 W 6 12807 11323 7323 Blue 20
3 PM Tue 77 75 W 6 12807 11323 7323 Blue 20
4 PM Tue 76 72 W 6 11481 9502 5502 Blue 17
5 PM Tue 75 70 W 6 10158 8869 4869 Blue 15
6 PM Tue 73 68 W 6 9206 8400 4400 Blue 13
7 PM Tue 68 63 W 6 7938 7155 3155 Blue 8
8 PM Tue 64 59 NE 3 6810 5359 1359 Blue 4
9 PM Tue 62 57 NE 3 5872 4338 338 Blue 2
10 PM Tue 61 56 NE 3 5383 4000 0 Blue 2
11 PM Tue 60 55 NE 2 4869 4000 0 Blue 1
12 Midnight Wed 60 55 NE 2 4869 4000 0 Blue 1
1 AM Wed 58 53 NE 2 3919 4000 0 Blue 0
2 AM Wed 58 53 NE 3 3919 4000 0 Blue 0
3 AM Wed 59 54 NE 3 4344 4000 0 Blue 0
4 AM Wed 58 53 NE 3 3919 4000 0 Blue 0
5 AM Wed 56 51 NE 3 3615 4000 0 Blue 0
6 AM Wed 56 51 NE 3 3615 4000 0 Blue 0
7 AM Wed 55 50 NE 3 3615 4000 0 Blue 0
8 AM Wed 56 51 E 2 3615 4000 0 Blue 0
9 AM Wed 63 58 E 2 6347 4849 849 Blue 3
10 AM Wed 68 65 E 2 8437 7656 3656 Blue 10
11 AM Wed 71 69 SW 3 9598 8645 4645 Blue 14
12 Noon Wed 72 71 SW 3 10837 9141 5141 Blue 16
1 PM Wed 73 72 SW 3 11481 9502 5502 Blue 17
2 PM Wed 74 73 W 6 12095 10041 6041 Blue 18
3 PM Wed 75 73 W 6 12095 10041 6041 Blue 18
4 PM Wed 75 71 W 6 10837 9141 5141 Blue 16
5 PM Wed 73 68 W 6 9206 8400 4400 Blue 13
6 PM Wed 71 66 W 6 8684 7905 3905 Blue 11
7 PM Wed 67 62 W 6 7688 6766 2766 Blue 7
8 PM Wed 63 58 N 5 6347 4849 849 Blue 3
9 PM Wed 62 57 N 5 5872 4338 338 Blue 2
10 PM Wed 61 56 N 5 5383 4000 0 Blue 2
11 PM Wed 60 55 NE 3 4869 4000 0 Blue 1
12 Midnight Thu 59 54 NE 3 4344 4000 0 Blue 0
1 AM Thu 58 53 NE 3 3919 4000 0 Blue 0
2 AM Thu 58 53 NE 3 3919 4000 0 Blue 0
3 AM Thu 59 54 NE 3 4344 4000 0 Blue 0
4 AM Thu 58 53 NE 3 3919 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