Detailed Predictions for: Burn Launch
Launch Altitude (f): 6188
LZ Altitude (f): 3540
Sounding

Station:

KOAK

Date/Time:

25 AUG 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 Sun 55 52 S 5 5056 6188 0 Blue 0
6 AM Sun 56 53 S 5 5056 6188 0 Blue 0
7 AM Sun 58 55 S 5 5056 6188 0 Blue 0
8 AM Sun 60 57 SW 5 5056 6188 0 Blue 0
9 AM Sun 63 62 SW 5 5056 6188 0 Blue 0
10 AM Sun 66 66 SW 5 5756 6188 0 Blue 0
11 AM Sun 70 72 SW 9 7498 6970 782 Blue 4
12 Noon Sun 73 76 SW 9 9067 7624 1436 Blue 8
1 PM Sun 76 80 SW 9 10584 9306 3118 Blue 12
2 PM Sun 78 82 SW 13 10893 9829 3641 Blue 14
3 PM Sun 79 82 SW 13 10893 9829 3641 Blue 14
4 PM Sun 79 80 SW 13 10584 9306 3118 Blue 12
5 PM Sun 77 76 SW 14 9067 7624 1436 Blue 8
6 PM Sun 75 73 SW 14 7745 7245 1057 Blue 5
7 PM Sun 73 70 SW 14 7255 6235 47 Blue 2
8 PM Sun 69 66 SW 12 5756 6188 0 Blue 0
9 PM Sun 66 63 SW 12 5056 6188 0 Blue 0
10 PM Sun 63 60 SW 12 5056 6188 0 Blue 0
11 PM Sun 61 58 SW 2 5056 6188 0 Blue 0
12 Midnight Mon 60 57 SW 2 5056 6188 0 Blue 0
1 AM Mon 59 56 SW 2 5056 6188 0 Blue 0
2 AM Mon 58 55 W 2 5056 6188 0 Blue 0
3 AM Mon 57 54 W 2 5056 6188 0 Blue 0
4 AM Mon 55 52 W 2 5056 6188 0 Blue 0
5 AM Mon 54 51 NE 2 5056 6188 0 Blue 0
6 AM Mon 55 52 NE 2 5056 6188 0 Blue 0
7 AM Mon 57 54 NE 2 5056 6188 0 Blue 0
8 AM Mon 61 58 E 2 5056 6188 0 Blue 0
9 AM Mon 64 63 E 2 5056 6188 0 Blue 0
10 AM Mon 68 68 E 2 6699 6188 0 Blue 0
11 AM Mon 72 74 S 3 8622 7380 1192 Blue 6
12 Noon Mon 75 78 S 3 9596 8816 2628 Blue 10
1 PM Mon 79 83 S 3 11040 10526 4338 Blue 15
2 PM Mon 82 86 W 5 12477 11018 4830 Blue 18
3 PM Mon 84 87 W 5 12701 11164 4976 Blue 19
4 PM Mon 84 85 W 5 12006 10871 4683 Blue 17
5 PM Mon 84 83 W 7 11040 10526 4338 Blue 15
6 PM Mon 82 80 W 7 10584 9306 3118 Blue 12
7 PM Mon 79 76 W 7 9067 7624 1436 Blue 8
8 PM Mon 75 72 W 7 7498 6970 782 Blue 4
9 PM Mon 72 69 W 7 6977 6188 0 Blue 1
10 PM Mon 68 65 W 7 5264 6188 0 Blue 0
11 PM Mon 66 63 N 5 5056 6188 0 Blue 0
12 Midnight Tue 64 61 N 5 5056 6188 0 Blue 0
1 AM Tue 63 60 N 5 5056 6188 0 Blue 0
2 AM Tue 62 59 N 5 5056 6188 0 Blue 0
3 AM Tue 61 58 N 5 5056 6188 0 Blue 0
4 AM Tue 59 56 N 5 5056 6188 0 Blue 0
5 AM Tue 58 55 NE 3 5056 6188 0 Blue 0
6 AM Tue 59 56 NE 3 5056 6188 0 Blue 0
7 AM Tue 61 58 NE 3 5056 6188 0 Blue 0
8 AM Tue 64 61 NE 3 5056 6188 0 Blue 0
9 AM Tue 67 66 NE 3 5756 6188 0 Blue 0
10 AM Tue 71 71 NE 3 7385 6694 506 Blue 3
11 AM Tue 74 75 S 5 8834 7493 1305 Blue 7
12 Noon Tue 78 81 S 5 10746 9568 3380 Blue 13
1 PM Tue 82 85 S 5 12006 10871 4683 Blue 17
2 PM Tue 84 87 S 5 12701 11164 4976 Blue 19
3 PM Tue 85 87 S 5 12701 11164 4976 Blue 19
4 PM Tue 84 84 S 5 11188 10725 4537 Blue 16
5 PM Tue 82 81 SW 10 10746 9568 3380 Blue 13
6 PM Tue 79 77 SW 10 9332 8606 2418 Blue 9
7 PM Tue 76 73 SW 10 7745 7245 1057 Blue 5
8 PM Tue 73 70 SW 10 7255 6235 47 Blue 2
9 PM Tue 70 67 SW 10 6236 6188 0 Blue 0
10 PM Tue 66 63 SW 10 5056 6188 0 Blue 0
11 PM Tue 64 61 SW 3 5056 6188 0 Blue 0
12 Midnight Wed 63 60 SW 3 5056 6188 0 Blue 0
1 AM Wed 62 59 SW 3 5056 6188 0 Blue 0
2 AM Wed 61 58 SW 3 5056 6188 0 Blue 0
3 AM Wed 60 57 SW 3 5056 6188 0 Blue 0
4 AM Wed 59 56 SW 3 5056 6188 0 Blue 0
5 AM Wed 58 55 E 3 5056 6188 0 Blue 0
6 AM Wed 59 56 E 3 5056 6188 0 Blue 0
7 AM Wed 60 57 E 3 5056 6188 0 Blue 0
8 AM Wed 63 60 E 3 5056 6188 0 Blue 0
9 AM Wed 67 65 E 3 5264 6188 0 Blue 0
10 AM Wed 71 71 E 3 7385 6694 506 Blue 3
11 AM Wed 75 75 SW 8 8834 7493 1305 Blue 7
12 Noon Wed 77 77 SW 8 9332 8606 2418 Blue 9
1 PM Wed 79 80 SW 8 10584 9306 3118 Blue 12
2 PM Wed 80 81 SW 8 10746 9568 3380 Blue 13
3 PM Wed 81 81 SW 8 10746 9568 3380 Blue 13
4 PM Wed 80 79 SW 8 9859 9042 2854 Blue 11
5 PM Wed 79 77 SW 13 9332 8606 2418 Blue 9
6 PM Wed 76 73 SW 13 7745 7245 1057 Blue 5
7 PM Wed 73 70 SW 13 7255 6235 47 Blue 2
8 PM Wed 70 67 SW 13 6236 6188 0 Blue 0
9 PM Wed 67 64 SW 13 5056 6188 0 Blue 0
10 PM Wed 65 62 SW 13 5056 6188 0 Blue 0
11 PM Wed 64 61 SW 5 5056 6188 0 Blue 0
12 Midnight Thu 63 60 SW 5 5056 6188 0 Blue 0
1 AM Thu 62 59 SW 5 5056 6188 0 Blue 0
2 AM Thu 60 57 SW 5 5056 6188 0 Blue 0
3 AM Thu 58 55 SW 5 5056 6188 0 Blue 0
4 AM Thu 56 53 SW 5 5056 6188 0 Blue 0
5 AM Thu 56 53 SE 2 5056 6188 0 Blue 0
6 AM Thu 57 54 SE 2 5056 6188 0 Blue 0
7 AM Thu 60 57 SE 2 5056 6188 0 Blue 0
8 AM Thu 63 60 SE 2 5056 6188 0 Blue 0
9 AM Thu 66 64 SE 2 5056 6188 0 Blue 0
10 AM Thu 69 68 SE 2 6699 6188 0 Blue 0
11 AM Thu 71 72 SW 10 7498 6970 782 Blue 4
12 Noon Thu 73 75 SW 10 8834 7493 1305 Blue 7
1 PM Thu 75 78 SW 10 9596 8816 2628 Blue 10
2 PM Thu 76 78 SW 10 9596 8816 2628 Blue 10
3 PM Thu 77 79 SW 10 9859 9042 2854 Blue 11
4 PM Thu 77 77 SW 10 9332 8606 2418 Blue 9
5 PM Thu 76 75 SW 13 8834 7493 1305 Blue 7
6 PM Thu 74 71 SW 13 7385 6694 506 Blue 3
7 PM Thu 70 67 SW 13 6236 6188 0 Blue 0
8 PM Thu 67 64 SW 13 5056 6188 0 Blue 0
9 PM Thu 64 61 SW 13 5056 6188 0 Blue 0
10 PM Thu 62 59 SW 13 5056 6188 0 Blue 0
11 PM Thu 61 58 S 5 5056 6188 0 Blue 0
12 Midnight Fri 60 57 S 5 5056 6188 0 Blue 0
1 AM Fri 59 56 S 5 5056 6188 0 Blue 0
2 AM Fri 57 54 S 5 5056 6188 0 Blue 0
3 AM Fri 55 52 S 5 5056 6188 0 Blue 0
4 AM Fri 54 51 S 5 5056 6188 0 Blue 0
5 AM Fri 53 50 SE 3 5056 6188 0 Blue 0
6 AM Fri 54 51 SE 3 5056 6188 0 Blue 0
7 AM Fri 57 54 SE 3 5056 6188 0 Blue 0
8 AM Fri 60 57 SE 3 5056 6188 0 Blue 0
9 AM Fri 64 63 SE 3 5056 6188 0 Blue 0
10 AM Fri 67 67 SE 3 6236 6188 0 Blue 0
11 AM Fri 71 73 SW 9 7745 7245 1057 Blue 5
12 Noon Fri 73 76 SW 9 9067 7624 1436 Blue 8
1 PM Fri 75 79 SW 9 9859 9042 2854 Blue 11
2 PM Fri 77 80 SW 9 10584 9306 3118 Blue 12
3 PM Fri 78 80 SW 9 10584 9306 3118 Blue 12
4 PM Fri 77 78 SW 9 9596 8816 2628 Blue 10
5 PM Fri 76 75 SW 13 8834 7493 1305 Blue 7
6 PM Fri 73 71 SW 13 7385 6694 506 Blue 3
7 PM Fri 69 66 SW 13 5756 6188 0 Blue 0
8 PM Fri 66 63 SW 13 5056 6188 0 Blue 0
9 PM Fri 63 60 SW 13 5056 6188 0 Blue 0
10 PM Fri 61 58 SW 13 5056 6188 0 Blue 0
11 PM Fri 59 56 SW 6 5056 6188 0 Blue 0
12 Midnight Sat 58 55 SW 6 5056 6188 0 Blue 0
1 AM Sat 57 54 SW 6 5056 6188 0 Blue 0
2 AM Sat 55 52 SW 6 5056 6188 0 Blue 0
3 AM Sat 53 50 SW 6 5056 6188 0 Blue 0
4 AM Sat 52 49 SW 6 5056 6188 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