Detailed Predictions for: Lake Isabella Ground Launch Center
Launch Lat, Long, Altitude (f): 35.654428, -118.297628, 5000
LZ Altitude (f): 2591
Sounding

Station:

KVBG

Date/Time:

23 JUN 2021

Temp/Wind data from:

NOAA Digital Forecast

Site Forecasts
Time
(Local)
High
Temp

Puddle
Temp

Wind
(mph)
Wind
Gust
Thermal
Ceiling

(ft)
Soaring
Ceiling

(ft)
Above
Launch

(ft)
Thermal
Type
Thermal
Index

(F)
12 Midnight Wed 75 75 W 8 16 4337 5000 0 Blue 11
1 AM Wed 70 70 SW 8 9 3461 5000 0 Blue 6
2 AM Wed 69 69 WSW 6 8 3366 5000 0 Blue 5
3 AM Wed 69 69 W 5 10 3366 5000 0 Blue 5
4 AM Wed 68 68 WNW 6 10 3272 5000 0 Blue 4
5 AM Wed 66 66 WNW 4 8 3082 5000 0 Blue 2
6 AM Wed 63 63 WNW 2 3 2623 5000 0 Blue 0
7 AM Wed 66 66 S 2 3 3082 5000 0 Blue 2
8 AM Wed 72 73 SSW 1 2 4052 5000 0 Blue 9
9 AM Wed 77 80 SSE 1 2 6335 5249 249 Blue 16
10 AM Wed 82 87 ENE 0 0 8893 8113 3113 Blue 23
11 AM Wed 86 92 NNW 3 5 11023 9756 4756 Blue 28
12 Noon Wed 90 95 WNW 5 9 12799 10855 5855 Blue 31
1 PM Wed 91 95 WNW 10 17 12799 10855 5855 Blue 31
2 PM Wed 93 96 SSW 10 17 13346 11467 6467 Blue 32
3 PM Wed 94 98 W 18 29 14410 12617 7617 White 34
4 PM Wed 94 97 W 21 35 13874 12054 7054 Blue 33
5 PM Wed 93 95 W 19 31 12799 10855 5855 Blue 31
6 PM Wed 92 93 W 17 27 11641 10071 5071 Blue 29
7 PM Wed 90 90 W 17 26 10146 8766 3766 Blue 26
8 PM Wed 84 84 W 2 4 8146 6980 1980 Blue 20
9 PM Wed 80 80 W 3 5 6335 5249 249 Blue 16
10 PM Wed 76 76 WNW 4 8 4629 5000 0 Blue 12
11 PM Wed 73 73 WNW 4 8 4052 5000 0 Blue 9
12 Midnight Thu 71 71 WNW 4 8 3556 5000 0 Blue 7
1 AM Thu 69 69 WNW 3 5 3366 5000 0 Blue 5
2 AM Thu 67 67 WNW 3 5 3177 5000 0 Blue 3
3 AM Thu 65 65 WNW 3 5 2949 5000 0 Blue 1
4 AM Thu 63 63 NW 4 8 2623 5000 0 Blue 0
5 AM Thu 61 61 NW 4 8 2533 5000 0 Blue 0
6 AM Thu 59 59 NNW 3 5 2533 5000 0 Blue 0
7 AM Thu 62 62 NNW 2 4 2533 5000 0 Blue 0
8 AM Thu 69 70 N 1 2 3461 5000 0 Blue 6
9 AM Thu 73 76 NW 1 2 4629 5000 0 Blue 12
10 AM Thu 78 83 W 2 4 7934 6236 1236 Blue 19
11 AM Thu 83 90 WSW 3 8 10146 8766 3766 Blue 26
12 Noon Thu 88 97 WSW 4 8 13874 12054 7054 Blue 33
1 PM Thu 91 100 WSW 5 8 14818 13684 8684 White 36
2 PM Thu 92 100 W 6 17 14818 13684 8684 White 36
3 PM Thu 93 100 W 10 17 14818 13684 8684 White 36
4 PM Thu 93 98 W 12 17 14410 12617 7617 White 34
5 PM Thu 92 95 W 14 23 12799 10855 5855 Blue 31
6 PM Thu 90 91 W 13 23 10430 9400 4400 Blue 27
7 PM Thu 87 87 W 11 23 8893 8113 3113 Blue 23
8 PM Thu 83 83 WNW 10 19 7934 6236 1236 Blue 19
9 PM Thu 80 80 WNW 11 19 6335 5249 249 Blue 16
10 PM Thu 76 76 WNW 12 19 4629 5000 0 Blue 12
11 PM Thu 73 73 NW 13 23 4052 5000 0 Blue 9
12 Midnight Fri 71 71 NW 13 23 3556 5000 0 Blue 7
1 AM Fri 69 69 NW 12 23 3366 5000 0 Blue 5
2 AM Fri 67 67 NW 11 18 3177 5000 0 Blue 3
3 AM Fri 64 64 NW 10 18 2746 5000 0 Blue 0
4 AM Fri 62 62 WNW 10 18 2533 5000 0 Blue 0
5 AM Fri 61 61 WNW 9 13 2533 5000 0 Blue 0
6 AM Fri 62 62 WNW 8 13 2533 5000 0 Blue 0
7 AM Fri 65 65 W 6 13 2949 5000 0 Blue 1
8 AM Fri 69 70 W 6 10 3461 5000 0 Blue 6
9 AM Fri 73 76 WSW 5 10 4629 5000 0 Blue 12
10 AM Fri 78 83 WSW 5 10 7934 6236 1236 Blue 19
11 AM Fri 83 90 SW 5 8 10146 8766 3766 Blue 26
12 Noon Fri 87 96 SW 5 8 13346 11467 6467 Blue 32
1 PM Fri 91 100 WSW 6 8 14818 13684 8684 White 36
2 PM Fri 93 100 WSW 8 12 14818 13684 8684 White 36
3 PM Fri 95 101 WSW 9 12 15022 14192 9192 White 37
4 PM Fri 95 99 W 11 12 14615 13160 8160 White 35
5 PM Fri 94 97 W 13 23 13874 12054 7054 Blue 33
6 PM Fri 92 93 W 17 23 11641 10071 5071 Blue 29
7 PM Fri 89 89 W 20 23 9828 8498 3498 Blue 25
8 PM Fri 85 85 WNW 17 23 8340 7426 2426 Blue 21
9 PM Fri 82 82 WNW 17 23 7492 5728 728 Blue 18
10 PM Fri 79 79 WNW 17 23 5750 5000 0 Blue 15
11 PM Fri 76 76 WNW 12 16 4629 5000 0 Blue 12
12 Midnight Sat 74 74 WNW 12 16 4194 5000 0 Blue 10
1 AM Sat 72 72 WNW 12 16 3909 5000 0 Blue 8
2 AM Sat 70 70 NW 10 11 3461 5000 0 Blue 6
3 AM Sat 67 67 NW 10 11 3177 5000 0 Blue 3
4 AM Sat 66 66 NW 10 11 3082 5000 0 Blue 2
5 AM Sat 65 65 NNW 8 10 2949 5000 0 Blue 1
6 AM Sat 66 66 NNW 8 10 3082 5000 0 Blue 2
7 AM Sat 70 70 NNW 8 10 3461 5000 0 Blue 6
8 AM Sat 74 75 NNW 5 9 4337 5000 0 Blue 11
9 AM Sat 79 82 NNW 5 9 7492 5728 728 Blue 18
10 AM Sat 85 90 NNW 5 9 10146 8766 3766 Blue 26
11 AM Sat 91 98 E 10 17 14410 12617 7617 White 34
12 Noon Sat 95 103 E 10 17 15422 15160 10160 White 39
1 PM Sat 99 108 E 10 17 16412 16412 11412 White 44
2 PM Sat 101 109 ESE 16 23 16609 16609 11609 White 45
3 PM Sat 103 109 ESE 16 23 16609 16609 11609 White 45
4 PM Sat 103 108 ESE 16 23 16412 16412 11412 White 44
5 PM Sat 102 105 W 17 24 15820 15820 10820 White 41
6 PM Sat 100 101 W 17 24 15022 14192 9192 White 37
7 PM Sat 97 97 W 17 24 13874 12054 7054 Blue 33
8 PM Sat 93 93 W 13 20 11641 10071 5071 Blue 29
9 PM Sat 90 90 W 13 20 10146 8766 3766 Blue 26
10 PM Sat 86 86 W 13 20 8533 7863 2863 Blue 22
11 PM Sat 83 83 NW 10 12 7934 6236 1236 Blue 19
12 Midnight Sun 80 80 NW 10 12 6335 5249 249 Blue 16
1 AM Sun 78 78 NW 10 12 5509 5000 0 Blue 14
2 AM Sun 76 76 NW 10 10 4629 5000 0 Blue 12
3 AM Sun 73 73 NW 10 10 4052 5000 0 Blue 9
4 AM Sun 71 71 NW 10 10 3556 5000 0 Blue 7
5 AM Sun 71 71 NNW 9 10 3556 5000 0 Blue 7
6 AM Sun 73 73 NNW 9 10 4052 5000 0 Blue 9
7 AM Sun 76 76 NNW 9 10 4629 5000 0 Blue 12
8 AM Sun 80 81 N 5 9 7041 5489 489 Blue 17
9 AM Sun 85 88 N 5 9 9508 8306 3306 Blue 24
10 AM Sun 91 96 N 5 9 13346 11467 6467 Blue 32
11 AM Sun 96 103 E 10 16 15422 15160 10160 White 39
12 Noon Sun 100 108 E 10 16 16412 16412 11412 White 44
1 PM Sun 102 111 E 10 16 17000 17000 12000 White 47
2 PM Sun 104 112 ESE 16 20 17194 17194 12194 White 48
3 PM Sun 106 112 ESE 16 20 17194 17194 12194 White 48
4 PM Sun 107 112 ESE 16 20 17194 17194 12194 White 48
5 PM Sun 106 108 WNW 16 21 16412 16412 11412 White 44
6 PM Sun 104 105 WNW 16 21 15820 15820 10820 White 41
7 PM Sun 101 101 WNW 16 21 15022 14192 9192 White 37
8 PM Sun 97 97 W 13 19 13874 12054 7054 Blue 33
9 PM Sun 94 94 W 13 19 12232 10365 5365 Blue 30
10 PM Sun 90 90 W 13 19 10146 8766 3766 Blue 26
11 PM Sun 87 87 NW 10 12 8893 8113 3113 Blue 23
12 Midnight Mon 84 84 NW 10 12 8146 6980 1980 Blue 20
1 AM Mon 81 81 NW 10 12 7041 5489 489 Blue 17
2 AM Mon 79 79 NW 8 9 5750 5000 0 Blue 15
3 AM Mon 76 76 NW 8 9 4629 5000 0 Blue 12
4 AM Mon 74 74 NW 8 9 4194 5000 0 Blue 10
5 AM Mon 74 74 NNW 8 9 4194 5000 0 Blue 10
6 AM Mon 75 75 NNW 8 9 4337 5000 0 Blue 11
7 AM Mon 78 78 NNW 8 9 5509 5000 0 Blue 14
8 AM Mon 82 83 ENE 5 9 7934 6236 1236 Blue 19
9 AM Mon 87 90 ENE 5 9 10146 8766 3766 Blue 26
10 AM Mon 92 97 ENE 5 9 13874 12054 7054 Blue 33
11 AM Mon 97 104 ESE 11 17 15622 15516 10516 White 40
12 Noon Mon 101 109 ESE 11 17 16609 16609 11609 White 45
1 PM Mon 104 112 ESE 11 17 17194 17194 12194 White 48
2 PM Mon 106 113 SSE 17 24 17390 17390 12390 White 49
3 PM Mon 107 112 SSE 17 24 17194 17194 12194 White 48
4 PM Mon 107 111 SSE 17 24 17000 17000 12000 White 47
5 PM Mon 106 108 WSW 16 24 16412 16412 11412 White 44
6 PM Mon 103 104 WSW 16 24 15622 15516 10516 White 40
7 PM Mon 100 100 WSW 16 24 14818 13684 8684 White 36
8 PM Mon 96 96 W 13 20 13346 11467 6467 Blue 32
9 PM Mon 93 93 W 13 20 11641 10071 5071 Blue 29
10 PM Mon 89 89 W 13 20 9828 8498 3498 Blue 25

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 or WeatherAPI.com website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the National Weather Service or WeatherAPI.com 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 or WeatherAPI.com website.

Wind Gust: This estimate is taken from the National Weather Service or WeatherAPI.com 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 [email protected]