Detailed Predictions for: Lake Isabella Ground Launch Center
Launch Altitude (f): 5000
LZ Altitude (f): 2591
Sounding

Station:

KVBG

Date/Time:

16 JUL 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 NW 10 2881 5000 0 Blue 0
6 AM Tue 69 69 W 9 2881 5000 0 Blue 0
7 AM Tue 71 71 W 8 2881 5000 0 Blue 0
8 AM Tue 72 73 W 8 2881 5000 0 Blue 0
9 AM Tue 76 79 W 10 2881 5000 0 Blue 0
10 AM Tue 81 86 W 10 4664 5000 0 Blue 2
11 AM Tue 84 91 W 14 7097 5567 567 Blue 7
12 Noon Tue 87 95 W 17 9646 7504 2504 Blue 11
1 PM Tue 89 98 W 20 11453 9395 4395 Blue 14
2 PM Tue 90 98 W 22 11453 9395 4395 Blue 14
3 PM Tue 91 98 W 22 11453 9395 4395 Blue 14
4 PM Tue 89 94 W 21 8487 7036 2036 Blue 10
5 PM Tue 88 91 W 21 7097 5567 567 Blue 7
6 PM Tue 87 88 W 20 5608 5000 0 Blue 4
7 PM Tue 84 84 W 18 3842 5000 0 Blue 0
8 PM Tue 80 80 W 16 2957 5000 0 Blue 0
9 PM Tue 78 78 W 17 2881 5000 0 Blue 0
10 PM Tue 77 77 W 16 2881 5000 0 Blue 0
11 PM Tue 75 75 W 14 2881 5000 0 Blue 0
12 Midnight Wed 75 75 W 14 2881 5000 0 Blue 0
1 AM Wed 74 74 W 13 2881 5000 0 Blue 0
2 AM Wed 73 73 W 12 2881 5000 0 Blue 0
3 AM Wed 72 72 W 10 2881 5000 0 Blue 0
4 AM Wed 71 71 NW 10 2881 5000 0 Blue 0
5 AM Wed 69 69 NW 9 2881 5000 0 Blue 0
6 AM Wed 66 66 W 7 2881 5000 0 Blue 0
7 AM Wed 69 69 NW 6 2881 5000 0 Blue 0
8 AM Wed 71 72 W 6 2881 5000 0 Blue 0
9 AM Wed 75 78 W 6 2881 5000 0 Blue 0
10 AM Wed 80 85 W 7 4256 5000 0 Blue 1
11 AM Wed 84 90 SW 9 6612 5052 52 Blue 6
12 Noon Wed 87 94 SW 9 8487 7036 2036 Blue 10
1 PM Wed 90 98 SW 9 11453 9395 4395 Blue 14
2 PM Wed 91 98 W 16 11453 9395 4395 Blue 14
3 PM Wed 92 98 W 16 11453 9395 4395 Blue 14
4 PM Wed 91 96 W 16 10797 7961 2961 Blue 12
5 PM Wed 90 93 W 16 8033 6558 1558 Blue 9
6 PM Wed 87 88 W 16 5608 5000 0 Blue 4
7 PM Wed 84 84 W 16 3842 5000 0 Blue 0
8 PM Wed 81 81 W 14 3158 5000 0 Blue 0
9 PM Wed 79 79 W 14 2881 5000 0 Blue 0
10 PM Wed 77 77 W 14 2881 5000 0 Blue 0
11 PM Wed 76 76 W 10 2881 5000 0 Blue 0
12 Midnight Thu 75 75 W 10 2881 5000 0 Blue 0
1 AM Thu 74 74 W 10 2881 5000 0 Blue 0
2 AM Thu 73 73 W 7 2881 5000 0 Blue 0
3 AM Thu 71 71 W 7 2881 5000 0 Blue 0
4 AM Thu 69 69 W 7 2881 5000 0 Blue 0
5 AM Thu 68 68 W 6 2881 5000 0 Blue 0
6 AM Thu 68 68 W 6 2881 5000 0 Blue 0
7 AM Thu 70 70 W 6 2881 5000 0 Blue 0
8 AM Thu 72 72 W 6 2881 5000 0 Blue 0
9 AM Thu 76 77 W 6 2881 5000 0 Blue 0
10 AM Thu 80 82 W 6 3357 5000 0 Blue 0
11 AM Thu 84 88 SW 10 5608 5000 0 Blue 4
12 Noon Thu 87 92 SW 10 7570 6069 1069 Blue 8
1 PM Thu 90 96 SW 10 10797 7961 2961 Blue 12
2 PM Thu 91 99 SW 17 11624 10520 5520 Blue 15
3 PM Thu 92 99 SW 17 11624 10520 5520 Blue 15
4 PM Thu 91 96 SW 17 10797 7961 2961 Blue 12
5 PM Thu 90 93 W 17 8033 6558 1558 Blue 9
6 PM Thu 87 88 W 17 5608 5000 0 Blue 4
7 PM Thu 84 84 W 17 3842 5000 0 Blue 0
8 PM Thu 81 81 W 14 3158 5000 0 Blue 0
9 PM Thu 79 79 W 14 2881 5000 0 Blue 0
10 PM Thu 77 77 W 14 2881 5000 0 Blue 0
11 PM Thu 75 75 W 12 2881 5000 0 Blue 0
12 Midnight Fri 74 74 W 12 2881 5000 0 Blue 0
1 AM Fri 72 72 W 12 2881 5000 0 Blue 0
2 AM Fri 71 71 W 8 2881 5000 0 Blue 0
3 AM Fri 69 69 W 8 2881 5000 0 Blue 0
4 AM Fri 68 68 W 8 2881 5000 0 Blue 0
5 AM Fri 67 67 NW 7 2881 5000 0 Blue 0
6 AM Fri 67 67 NW 7 2881 5000 0 Blue 0
7 AM Fri 67 67 NW 7 2881 5000 0 Blue 0
8 AM Fri 69 69 W 6 2881 5000 0 Blue 0
9 AM Fri 73 74 W 6 2881 5000 0 Blue 0
10 AM Fri 78 80 W 6 2957 5000 0 Blue 0
11 AM Fri 82 86 SW 10 4664 5000 0 Blue 2
12 Noon Fri 85 90 SW 10 6612 5052 52 Blue 6
1 PM Fri 88 93 SW 10 8033 6558 1558 Blue 9
2 PM Fri 89 89 SW 17 6117 5000 0 Blue 5
3 PM Fri 90 90 SW 17 6612 5052 52 Blue 6
4 PM Fri 89 89 SW 17 6117 5000 0 Blue 5
5 PM Fri 88 89 W 17 6117 5000 0 Blue 5
6 PM Fri 85 85 W 17 4256 5000 0 Blue 1
7 PM Fri 82 82 W 17 3357 5000 0 Blue 0
8 PM Fri 79 79 W 14 2881 5000 0 Blue 0
9 PM Fri 77 77 W 14 2881 5000 0 Blue 0
10 PM Fri 75 75 W 14 2881 5000 0 Blue 0
11 PM Fri 73 73 W 12 2881 5000 0 Blue 0
12 Midnight Sat 72 72 W 12 2881 5000 0 Blue 0
1 AM Sat 71 71 W 12 2881 5000 0 Blue 0
2 AM Sat 70 70 W 8 2881 5000 0 Blue 0
3 AM Sat 68 68 W 8 2881 5000 0 Blue 0
4 AM Sat 67 67 W 8 2881 5000 0 Blue 0
5 AM Sat 66 66 W 7 2881 5000 0 Blue 0
6 AM Sat 66 66 W 7 2881 5000 0 Blue 0
7 AM Sat 66 66 W 7 2881 5000 0 Blue 0
8 AM Sat 68 69 W 6 2881 5000 0 Blue 0
9 AM Sat 72 75 W 6 2881 5000 0 Blue 0
10 AM Sat 77 82 W 6 3357 5000 0 Blue 0
11 AM Sat 81 88 SW 10 5608 5000 0 Blue 4
12 Noon Sat 84 92 SW 10 7570 6069 1069 Blue 8
1 PM Sat 87 96 SW 10 10797 7961 2961 Blue 12
2 PM Sat 88 96 SW 17 10797 7961 2961 Blue 12
3 PM Sat 89 96 SW 17 10797 7961 2961 Blue 12
4 PM Sat 89 94 SW 17 8487 7036 2036 Blue 10
5 PM Sat 88 91 SW 16 7097 5567 567 Blue 7
6 PM Sat 85 86 SW 16 4664 5000 0 Blue 2
7 PM Sat 82 82 SW 16 3357 5000 0 Blue 0
8 PM Sat 79 79 W 13 2881 5000 0 Blue 0
9 PM Sat 77 77 W 13 2881 5000 0 Blue 0
10 PM Sat 75 75 W 13 2881 5000 0 Blue 0
11 PM Sat 74 74 W 10 2881 5000 0 Blue 0
12 Midnight Sun 73 73 W 10 2881 5000 0 Blue 0
1 AM Sun 73 73 W 10 2881 5000 0 Blue 0
2 AM Sun 72 72 W 7 2881 5000 0 Blue 0
3 AM Sun 70 70 W 7 2881 5000 0 Blue 0
4 AM Sun 68 68 W 7 2881 5000 0 Blue 0
5 AM Sun 67 67 W 6 2881 5000 0 Blue 0
6 AM Sun 67 67 W 6 2881 5000 0 Blue 0
7 AM Sun 69 69 W 6 2881 5000 0 Blue 0
8 AM Sun 71 72 W 5 2881 5000 0 Blue 0
9 AM Sun 75 78 W 5 2881 5000 0 Blue 0
10 AM Sun 79 84 W 5 3842 5000 0 Blue 0
11 AM Sun 83 89 S 9 6117 5000 0 Blue 5
12 Noon Sun 86 94 S 9 8487 7036 2036 Blue 10
1 PM Sun 89 97 S 9 11282 8410 3410 Blue 13
2 PM Sun 91 99 S 15 11624 10520 5520 Blue 15
3 PM Sun 92 98 S 15 11453 9395 4395 Blue 14
4 PM Sun 91 96 S 15 10797 7961 2961 Blue 12
5 PM Sun 90 92 SW 14 7570 6069 1069 Blue 8
6 PM Sun 88 89 SW 14 6117 5000 0 Blue 5
7 PM Sun 85 85 SW 14 4256 5000 0 Blue 1
8 PM Sun 82 82 W 12 3357 5000 0 Blue 0
9 PM Sun 80 80 W 12 2957 5000 0 Blue 0
10 PM Sun 78 78 W 12 2881 5000 0 Blue 0
11 PM Sun 77 77 W 10 2881 5000 0 Blue 0
12 Midnight Mon 76 76 W 10 2881 5000 0 Blue 0
1 AM Mon 75 75 W 10 2881 5000 0 Blue 0
2 AM Mon 74 74 W 6 2881 5000 0 Blue 0
3 AM Mon 72 72 W 6 2881 5000 0 Blue 0
4 AM Mon 71 71 W 6 2881 5000 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