Detailed Predictions for: Jean Ridge
Launch Altitude (f): 3304
LZ Altitude (f): 2844
Sounding

Station:

KREV

Date/Time:

20 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 Tue 70 70 SW 8 5680 5240 1936 Blue 6
6 AM Tue 70 70 SW 7 5680 5240 1936 Blue 6
7 AM Tue 69 69 W 6 5577 5077 1773 Blue 5
8 AM Tue 78 79 W 6 8435 7622 4318 Blue 15
9 AM Tue 85 88 SW 5 15525 13298 9994 White 24
10 AM Tue 90 94 SE 5 16747 16468 13164 White 30
11 AM Tue 93 99 E 5 17750 17750 14446 White 35
12 Noon Tue 97 105 SE 5 18945 18945 15641 White 41
1 PM Tue 99 107 S 6 19387 19387 16083 White 43
2 PM Tue 102 109 S 6 19778 19778 16474 White 45
3 PM Tue 102 108 S 7 19584 19584 16280 White 44
4 PM Tue 103 107 SW 8 19387 19387 16083 White 43
5 PM Tue 101 103 SW 8 18547 18547 15243 White 39
6 PM Tue 99 99 SW 8 17750 17750 14446 White 35
7 PM Tue 95 95 SW 8 16949 16681 13377 White 31
8 PM Tue 91 91 SW 8 16140 16031 12727 White 27
9 PM Tue 88 88 SW 8 15525 13298 9994 White 24
10 PM Tue 84 84 SW 9 12572 9348 6044 Blue 20
11 PM Tue 83 83 SW 9 11476 8796 5492 Blue 19
12 Midnight Wed 81 81 SW 9 9464 7981 4677 Blue 17
1 AM Wed 79 79 SW 9 8435 7622 4318 Blue 15
2 AM Wed 78 78 SW 9 8018 7442 4138 Blue 14
3 AM Wed 76 76 SW 9 7637 7080 3776 Blue 12
4 AM Wed 73 73 SW 9 7092 5678 2374 Blue 9
5 AM Wed 72 72 SW 8 6595 5575 2271 Blue 8
6 AM Wed 72 72 SW 7 6595 5575 2271 Blue 8
7 AM Wed 73 73 W 6 7092 5678 2374 Blue 9
8 AM Wed 81 82 W 6 10267 8390 5086 Blue 18
9 AM Wed 86 89 W 5 15730 14201 10897 White 25
10 AM Wed 91 95 N 5 16949 16681 13377 White 31
11 AM Wed 95 101 NE 5 18150 18150 14846 White 37
12 Noon Wed 97 105 NE 6 18945 18945 15641 White 41
1 PM Wed 100 108 SE 6 19584 19584 16280 White 44
2 PM Wed 102 109 SE 6 19778 19778 16474 White 45
3 PM Wed 103 109 SE 7 19778 19778 16474 White 45
4 PM Wed 103 107 S 7 19387 19387 16083 White 43
5 PM Wed 102 104 S 8 18746 18746 15442 White 40
6 PM Wed 98 98 S 8 17550 17550 14246 White 34
7 PM Wed 94 94 SW 9 16747 16468 13164 White 30
8 PM Wed 90 90 SW 10 15936 15814 12510 White 26
9 PM Wed 87 87 SW 10 15319 12326 9022 White 23
10 PM Wed 85 85 SW 10 13561 10139 6835 Blue 21
11 PM Wed 83 83 SW 10 11476 8796 5492 Blue 19
12 Midnight Thu 82 82 SW 12 10267 8390 5086 Blue 18
1 AM Thu 80 80 SW 12 8845 7802 4498 Blue 16
2 AM Thu 78 78 SW 12 8018 7442 4138 Blue 14
3 AM Thu 76 76 SW 12 7637 7080 3776 Blue 12
4 AM Thu 75 75 SW 10 7456 6558 3254 Blue 11
5 AM Thu 74 74 SW 10 7274 5823 2519 Blue 10
6 AM Thu 75 75 SW 9 7456 6558 3254 Blue 11
7 AM Thu 78 78 SW 8 8018 7442 4138 Blue 14
8 AM Thu 82 83 SW 8 11476 8796 5492 Blue 19
9 AM Thu 87 89 SW 8 15730 14201 10897 White 25
10 AM Thu 93 97 S 9 17349 17349 14045 White 33
11 AM Thu 97 103 S 10 18547 18547 15243 White 39
12 Noon Thu 100 107 S 12 19387 19387 16083 White 43
1 PM Thu 102 109 S 14 19778 19778 16474 White 45
2 PM Thu 103 109 S 15 19778 19778 16474 White 45
3 PM Thu 103 108 S 15 19584 19584 16280 White 44
4 PM Thu 102 105 S 16 18945 18945 15641 White 41
5 PM Thu 101 103 SW 15 18547 18547 15243 White 39
6 PM Thu 98 98 SW 14 17550 17550 14246 White 34
7 PM Thu 94 94 SW 12 16747 16468 13164 White 30
8 PM Thu 90 90 SW 10 15936 15814 12510 White 26
9 PM Thu 87 87 SW 10 15319 12326 9022 White 23
10 PM Thu 84 84 SW 10 12572 9348 6044 Blue 20
11 PM Thu 82 82 SW 10 10267 8390 5086 Blue 18
12 Midnight Fri 80 80 S 10 8845 7802 4498 Blue 16
1 AM Fri 79 79 S 9 8435 7622 4318 Blue 15
2 AM Fri 77 77 S 9 7818 7261 3957 Blue 13
3 AM Fri 74 74 S 9 7274 5823 2519 Blue 10
4 AM Fri 73 73 S 9 7092 5678 2374 Blue 9
5 AM Fri 72 72 S 9 6595 5575 2271 Blue 8
6 AM Fri 73 73 S 9 7092 5678 2374 Blue 9
7 AM Fri 76 76 S 9 7637 7080 3776 Blue 12
8 AM Fri 80 81 S 9 9464 7981 4677 Blue 17
9 AM Fri 84 86 S 9 15112 11234 7930 White 22
10 AM Fri 89 93 S 9 16545 16317 13013 White 29
11 AM Fri 93 99 S 9 17750 17750 14446 White 35
12 Noon Fri 96 103 S 10 18547 18547 15243 White 39
1 PM Fri 98 105 S 12 18945 18945 15641 White 41
2 PM Fri 99 106 S 13 19172 19172 15868 White 42
3 PM Fri 99 104 S 14 18746 18746 15442 White 40
4 PM Fri 99 103 S 14 18547 18547 15243 White 39
5 PM Fri 97 99 S 13 17750 17750 14446 White 35
6 PM Fri 95 95 S 12 16949 16681 13377 White 31
7 PM Fri 92 92 S 10 16342 16174 12870 White 28
8 PM Fri 89 89 S 9 15730 14201 10897 White 25
9 PM Fri 86 86 S 9 15112 11234 7930 White 22
10 PM Fri 84 84 S 9 12572 9348 6044 Blue 20
11 PM Fri 82 82 S 9 10267 8390 5086 Blue 18
12 Midnight Sat 80 80 S 9 8845 7802 4498 Blue 16
1 AM Sat 78 78 S 9 8018 7442 4138 Blue 14
2 AM Sat 76 76 S 8 7637 7080 3776 Blue 12
3 AM Sat 74 74 S 8 7274 5823 2519 Blue 10
4 AM Sat 73 73 S 8 7092 5678 2374 Blue 9
5 AM Sat 72 72 S 8 6595 5575 2271 Blue 8
6 AM Sat 73 73 S 8 7092 5678 2374 Blue 9
7 AM Sat 76 76 S 8 7637 7080 3776 Blue 12
8 AM Sat 80 81 S 8 9464 7981 4677 Blue 17
9 AM Sat 84 86 S 8 15112 11234 7930 White 22
10 AM Sat 89 93 S 8 16545 16317 13013 White 29
11 AM Sat 93 99 S 8 17750 17750 14446 White 35
12 Noon Sat 95 102 S 9 18348 18348 15044 White 38
1 PM Sat 97 105 SW 10 18945 18945 15641 White 41
2 PM Sat 98 105 SW 12 18945 18945 15641 White 41
3 PM Sat 99 104 SW 12 18746 18746 15442 White 40
4 PM Sat 99 103 SW 12 18547 18547 15243 White 39
5 PM Sat 98 100 SW 12 17950 17950 14646 White 36
6 PM Sat 95 95 SW 10 16949 16681 13377 White 31
7 PM Sat 92 92 SW 10 16342 16174 12870 White 28
8 PM Sat 89 89 SW 10 15730 14201 10897 White 25
9 PM Sat 86 86 SW 10 15112 11234 7930 White 22
10 PM Sat 84 84 SW 10 12572 9348 6044 Blue 20
11 PM Sat 82 82 SW 10 10267 8390 5086 Blue 18
12 Midnight Sun 81 81 SW 9 9464 7981 4677 Blue 17
1 AM Sun 80 80 SW 9 8845 7802 4498 Blue 16
2 AM Sun 78 78 SW 9 8018 7442 4138 Blue 14
3 AM Sun 76 76 SW 8 7637 7080 3776 Blue 12
4 AM Sun 74 74 SW 9 7274 5823 2519 Blue 10
5 AM Sun 73 73 SW 9 7092 5678 2374 Blue 9
6 AM Sun 74 74 SW 8 7274 5823 2519 Blue 10
7 AM Sun 77 77 SW 8 7818 7261 3957 Blue 13
8 AM Sun 81 82 SW 7 10267 8390 5086 Blue 18
9 AM Sun 86 88 SW 7 15525 13298 9994 White 24
10 AM Sun 90 94 SW 7 16747 16468 13164 White 30
11 AM Sun 94 100 SW 7 17950 17950 14646 White 36
12 Noon Sun 96 103 SW 8 18547 18547 15243 White 39
1 PM Sun 98 105 SW 8 18945 18945 15641 White 41
2 PM Sun 99 105 SW 8 18945 18945 15641 White 41
3 PM Sun 100 105 SW 8 18945 18945 15641 White 41
4 PM Sun 100 103 SW 8 18547 18547 15243 White 39
5 PM Sun 99 101 SW 8 18150 18150 14846 White 37
6 PM Sun 96 96 SW 9 17149 17052 13748 White 32
7 PM Sun 93 93 SW 9 16545 16317 13013 White 29
8 PM Sun 89 89 SW 10 15730 14201 10897 White 25
9 PM Sun 86 86 SW 10 15112 11234 7930 White 22
10 PM Sun 84 84 SW 10 12572 9348 6044 Blue 20
11 PM Sun 83 83 SW 10 11476 8796 5492 Blue 19
12 Midnight Mon 81 81 SW 9 9464 7981 4677 Blue 17
1 AM Mon 80 80 SW 9 8845 7802 4498 Blue 16
2 AM Mon 78 78 SW 8 8018 7442 4138 Blue 14
3 AM Mon 76 76 SW 8 7637 7080 3776 Blue 12
4 AM Mon 75 75 SW 8 7456 6558 3254 Blue 11

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