Detailed Predictions for: Dunlap
Launch Altitude (f): 4460
LZ Altitude (f): 1950
Sounding

Station:

KOAK

Date/Time:

22 JUL 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 Sun 73 68 SE 2 2716 4460 0 Blue 12
6 AM Sun 73 68 SE 2 2716 4460 0 Blue 12
7 AM Sun 74 69 SE 2 2734 4460 0 Blue 13
8 AM Sun 76 72 S 3 2791 4460 0 Blue 16
9 AM Sun 79 76 S 3 2871 4460 0 Blue 20
10 AM Sun 82 81 S 3 3806 4460 0 Blue 25
11 AM Sun 85 85 SW 8 5444 4460 0 Blue 29
12 Noon Sun 88 90 SW 8 7577 6112 1652 Blue 34
1 PM Sun 90 92 SW 8 8808 7197 2737 Blue 36
2 PM Sun 92 94 SW 8 9479 8086 3626 Blue 38
3 PM Sun 93 94 SW 8 9479 8086 3626 Blue 38
4 PM Sun 94 93 SW 8 9224 7487 3027 Blue 37
5 PM Sun 94 92 W 8 8808 7197 2737 Blue 36
6 PM Sun 93 89 W 8 7241 5841 1381 Blue 33
7 PM Sun 91 86 W 8 5870 4537 77 Blue 30
8 PM Sun 88 83 NW 6 4561 4460 0 Blue 27
9 PM Sun 86 81 NW 6 3806 4460 0 Blue 25
10 PM Sun 83 78 NW 6 3078 4460 0 Blue 22
11 PM Sun 81 76 NE 6 2871 4460 0 Blue 20
12 Midnight Mon 79 74 NE 6 2828 4460 0 Blue 18
1 AM Mon 78 73 NE 6 2810 4460 0 Blue 17
2 AM Mon 77 72 E 6 2791 4460 0 Blue 16
3 AM Mon 76 71 E 6 2772 4460 0 Blue 15
4 AM Mon 75 70 E 6 2753 4460 0 Blue 14
5 AM Mon 74 69 SW 2 2734 4460 0 Blue 13
6 AM Mon 74 69 SW 2 2734 4460 0 Blue 13
7 AM Mon 75 70 SW 2 2753 4460 0 Blue 14
8 AM Mon 77 73 W 1 2810 4460 0 Blue 17
9 AM Mon 81 79 W 1 3310 4460 0 Blue 23
10 AM Mon 84 83 W 1 4561 4460 0 Blue 27
11 AM Mon 88 89 SW 8 7241 5841 1381 Blue 33
12 Noon Mon 91 93 SW 8 9224 7487 3027 Blue 37
1 PM Mon 93 96 SW 8 10365 9168 4708 Blue 40
2 PM Mon 95 97 W 7 10730 9421 4961 Blue 41
3 PM Mon 96 97 W 7 10730 9421 4961 Blue 41
4 PM Mon 97 96 W 7 10365 9168 4708 Blue 40
5 PM Mon 97 95 NW 8 9652 8673 4213 Blue 39
6 PM Mon 96 92 NW 8 8808 7197 2737 Blue 36
7 PM Mon 93 88 NW 8 6417 5390 930 Blue 32
8 PM Mon 90 85 NW 8 5444 4460 0 Blue 29
9 PM Mon 87 82 NW 8 4194 4460 0 Blue 26
10 PM Mon 83 78 NW 8 3078 4460 0 Blue 22
11 PM Mon 81 76 NE 2 2871 4460 0 Blue 20
12 Midnight Tue 79 74 NE 2 2828 4460 0 Blue 18
1 AM Tue 78 73 NE 2 2810 4460 0 Blue 17
2 AM Tue 77 72 NE 2 2791 4460 0 Blue 16
3 AM Tue 76 71 NE 2 2772 4460 0 Blue 15
4 AM Tue 75 70 NE 2 2753 4460 0 Blue 14
5 AM Tue 74 69 E 1 2734 4460 0 Blue 13
6 AM Tue 74 69 E 1 2734 4460 0 Blue 13
7 AM Tue 75 70 E 1 2753 4460 0 Blue 14
8 AM Tue 78 74 E 1 2828 4460 0 Blue 18
9 AM Tue 82 79 E 1 3310 4460 0 Blue 23
10 AM Tue 86 85 E 1 5444 4460 0 Blue 29
11 AM Tue 90 91 W 8 8187 6383 1923 Blue 35
12 Noon Tue 93 95 W 8 9652 8673 4213 Blue 39
1 PM Tue 96 99 W 8 11644 10031 5571 Blue 43
2 PM Tue 97 99 W 8 11644 10031 5571 Blue 43
3 PM Tue 99 100 W 8 12313 10658 6198 Blue 44
4 PM Tue 100 100 W 8 12313 10658 6198 Blue 44
5 PM Tue 100 98 NW 5 10997 9612 5152 Blue 42
6 PM Tue 99 95 NW 5 9652 8673 4213 Blue 39
7 PM Tue 96 91 NW 5 8187 6383 1923 Blue 35
8 PM Tue 93 88 NW 5 6417 5390 930 Blue 32
9 PM Tue 90 85 NW 5 5444 4460 0 Blue 29
10 PM Tue 87 82 NW 5 4194 4460 0 Blue 26
11 PM Tue 84 79 NE 5 3310 4460 0 Blue 23
12 Midnight Wed 82 77 NE 5 2893 4460 0 Blue 21
1 AM Wed 81 76 NE 5 2871 4460 0 Blue 20
2 AM Wed 79 74 NE 5 2828 4460 0 Blue 18
3 AM Wed 78 73 NE 5 2810 4460 0 Blue 17
4 AM Wed 77 72 NE 5 2791 4460 0 Blue 16
5 AM Wed 76 71 SE 2 2772 4460 0 Blue 15
6 AM Wed 76 71 SE 2 2772 4460 0 Blue 15
7 AM Wed 77 72 SE 2 2791 4460 0 Blue 16
8 AM Wed 79 75 SE 2 2849 4460 0 Blue 19
9 AM Wed 83 80 SE 2 3558 4460 0 Blue 24
10 AM Wed 87 86 SE 2 5870 4537 77 Blue 30
11 AM Wed 91 92 W 6 8808 7197 2737 Blue 36
12 Noon Wed 94 96 W 6 10365 9168 4708 Blue 40
1 PM Wed 96 98 W 6 10997 9612 5152 Blue 42
2 PM Wed 98 100 W 6 12313 10658 6198 Blue 44
3 PM Wed 99 100 W 6 12313 10658 6198 Blue 44
4 PM Wed 101 100 W 6 12313 10658 6198 Blue 44
5 PM Wed 101 98 W 5 10997 9612 5152 Blue 42
6 PM Wed 99 95 W 5 9652 8673 4213 Blue 39
7 PM Wed 96 91 W 5 8187 6383 1923 Blue 35
8 PM Wed 93 88 W 5 6417 5390 930 Blue 32
9 PM Wed 89 84 W 5 4934 4460 0 Blue 28
10 PM Wed 86 81 W 5 3806 4460 0 Blue 25
11 PM Wed 83 78 SE 2 3078 4460 0 Blue 22
12 Midnight Thu 81 76 SE 2 2871 4460 0 Blue 20
1 AM Thu 80 75 SE 2 2849 4460 0 Blue 19
2 AM Thu 79 74 SE 2 2828 4460 0 Blue 18
3 AM Thu 77 72 SE 2 2791 4460 0 Blue 16
4 AM Thu 76 71 SE 2 2772 4460 0 Blue 15
5 AM Thu 75 70 NE 3 2753 4460 0 Blue 14
6 AM Thu 75 70 NE 3 2753 4460 0 Blue 14
7 AM Thu 76 71 NE 3 2772 4460 0 Blue 15
8 AM Thu 78 74 NE 3 2828 4460 0 Blue 18
9 AM Thu 82 79 NE 3 3310 4460 0 Blue 23
10 AM Thu 86 85 NE 3 5444 4460 0 Blue 29
11 AM Thu 90 91 W 3 8187 6383 1923 Blue 35
12 Noon Thu 93 95 W 3 9652 8673 4213 Blue 39
1 PM Thu 95 97 W 3 10730 9421 4961 Blue 41
2 PM Thu 98 100 W 3 12313 10658 6198 Blue 44
3 PM Thu 100 101 W 3 12949 10924 6464 Blue 45
4 PM Thu 101 100 W 3 12313 10658 6198 Blue 44
5 PM Thu 101 98 W 3 10997 9612 5152 Blue 42
6 PM Thu 99 95 W 3 9652 8673 4213 Blue 39
7 PM Thu 96 91 W 3 8187 6383 1923 Blue 35
8 PM Thu 92 87 W 3 6144 4905 445 Blue 31
9 PM Thu 88 83 W 3 4561 4460 0 Blue 27
10 PM Thu 84 79 W 3 3310 4460 0 Blue 23
11 PM Thu 82 77 W 5 2893 4460 0 Blue 21
12 Midnight Fri 80 75 W 5 2849 4460 0 Blue 19
1 AM Fri 79 74 W 5 2828 4460 0 Blue 18
2 AM Fri 78 73 W 5 2810 4460 0 Blue 17
3 AM Fri 77 72 W 5 2791 4460 0 Blue 16
4 AM Fri 76 71 W 5 2772 4460 0 Blue 15
5 AM Fri 75 70 E 3 2753 4460 0 Blue 14
6 AM Fri 75 70 E 3 2753 4460 0 Blue 14
7 AM Fri 76 71 E 3 2772 4460 0 Blue 15
8 AM Fri 78 74 E 3 2828 4460 0 Blue 18
9 AM Fri 81 79 E 3 3310 4460 0 Blue 23
10 AM Fri 85 85 E 3 5444 4460 0 Blue 29
11 AM Fri 88 89 E 3 7241 5841 1381 Blue 33
12 Noon Fri 91 94 E 3 9479 8086 3626 Blue 38
1 PM Fri 93 96 E 3 10365 9168 4708 Blue 40
2 PM Fri 95 98 E 3 10997 9612 5152 Blue 42
3 PM Fri 96 98 E 3 10997 9612 5152 Blue 42
4 PM Fri 97 97 E 3 10730 9421 4961 Blue 41
5 PM Fri 97 95 E 3 9652 8673 4213 Blue 39
6 PM Fri 95 91 E 3 8187 6383 1923 Blue 35
7 PM Fri 93 88 E 3 6417 5390 930 Blue 32
8 PM Fri 90 85 E 3 5444 4460 0 Blue 29
9 PM Fri 87 82 E 3 4194 4460 0 Blue 26
10 PM Fri 84 79 E 3 3310 4460 0 Blue 23
11 PM Fri 82 77 E 3 2893 4460 0 Blue 21
12 Midnight Sat 80 75 E 3 2849 4460 0 Blue 19
1 AM Sat 79 74 E 3 2828 4460 0 Blue 18
2 AM Sat 78 73 E 3 2810 4460 0 Blue 17
3 AM Sat 77 72 E 3 2791 4460 0 Blue 16
4 AM Sat 76 71 E 3 2772 4460 0 Blue 15

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