Detailed Predictions for: Calabasas
Launch Lat, Long, Altitude (f): 34.134575, -118.687689, 1640
LZ Altitude (f): 770
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 72 72 WNW 2 3 3001 2550 910 Blue 15
1 AM Wed 70 70 WNW 3 4 2675 2422 782 Blue 13
2 AM Wed 67 67 NW 3 4 2423 2294 654 Blue 10
3 AM Wed 68 68 WNW 2 3 2465 2337 697 Blue 11
4 AM Wed 69 69 W 1 2 2554 2379 739 Blue 12
5 AM Wed 70 70 WSW 1 1 2675 2422 782 Blue 13
6 AM Wed 70 70 SW 2 2 2675 2422 782 Blue 13
7 AM Wed 71 71 S 3 3 2797 2464 824 Blue 14
8 AM Wed 72 73 SE 4 4 3118 2671 1031 Blue 16
9 AM Wed 73 76 SSE 4 5 3398 3114 1474 Blue 19
10 AM Wed 75 80 S 5 6 4091 3486 1846 Blue 23
11 AM Wed 77 84 SSW 5 6 5317 4220 2580 Blue 27
12 Noon Wed 78 87 SSW 6 8 6460 5289 3649 Blue 30
1 PM Wed 79 88 SW 8 9 7095 5524 3884 Blue 31
2 PM Wed 81 90 SW 9 10 7967 6331 4691 Blue 33
3 PM Wed 80 87 WSW 9 11 6460 5289 3649 Blue 30
4 PM Wed 80 85 WSW 9 11 5554 4359 2719 Blue 28
5 PM Wed 79 82 WSW 10 11 4372 3940 2300 Blue 25
6 PM Wed 77 78 WSW 8 10 3609 3300 1660 Blue 21
7 PM Wed 75 75 W 7 8 3305 2996 1356 Blue 18
8 PM Wed 73 73 W 6 7 3118 2671 1031 Blue 16
9 PM Wed 72 72 W 5 5 3001 2550 910 Blue 15
10 PM Wed 71 71 WNW 3 4 2797 2464 824 Blue 14
11 PM Wed 71 71 WNW 2 2 2797 2464 824 Blue 14
12 Midnight Thu 71 71 W 2 2 2797 2464 824 Blue 14
1 AM Thu 70 70 WSW 1 2 2675 2422 782 Blue 13
2 AM Thu 70 70 SW 1 1 2675 2422 782 Blue 13
3 AM Thu 70 70 SW 1 1 2675 2422 782 Blue 13
4 AM Thu 69 69 WSW 0 0 2554 2379 739 Blue 12
5 AM Thu 68 68 WSW 0 0 2465 2337 697 Blue 11
6 AM Thu 69 69 SW 1 1 2554 2379 739 Blue 12
7 AM Thu 70 70 SSW 1 1 2675 2422 782 Blue 13
8 AM Thu 71 72 S 2 2 3001 2550 910 Blue 15
9 AM Thu 72 75 SSW 3 4 3305 2996 1356 Blue 18
10 AM Thu 74 79 SSW 4 5 3950 3393 1753 Blue 22
11 AM Thu 75 82 SSW 6 7 4372 3940 2300 Blue 25
12 Noon Thu 77 86 SW 6 8 5791 4735 3095 Blue 29
1 PM Thu 78 87 SW 7 8 6460 5289 3649 Blue 30
2 PM Thu 79 88 SW 8 9 7095 5524 3884 Blue 31
3 PM Thu 79 86 SW 8 10 5791 4735 3095 Blue 29
4 PM Thu 79 84 WSW 9 11 5317 4220 2580 Blue 27
5 PM Thu 79 82 WSW 9 11 4372 3940 2300 Blue 25
6 PM Thu 78 79 WSW 8 9 3950 3393 1753 Blue 22
7 PM Thu 76 76 W 6 7 3398 3114 1474 Blue 19
8 PM Thu 75 75 W 5 5 3305 2996 1356 Blue 18
9 PM Thu 74 74 WSW 3 4 3212 2792 1152 Blue 17
10 PM Thu 73 73 SW 2 2 3118 2671 1031 Blue 16
11 PM Thu 72 72 SSW 0 0 3001 2550 910 Blue 15
12 Midnight Fri 72 72 S 1 1 3001 2550 910 Blue 15
1 AM Fri 71 71 SE 2 2 2797 2464 824 Blue 14
2 AM Fri 71 71 ESE 2 3 2797 2464 824 Blue 14
3 AM Fri 70 70 ESE 2 2 2675 2422 782 Blue 13
4 AM Fri 69 69 ESE 1 1 2554 2379 739 Blue 12
5 AM Fri 68 68 ESE 0 1 2465 2337 697 Blue 11
6 AM Fri 70 70 ESE 1 1 2675 2422 782 Blue 13
7 AM Fri 71 71 SE 2 2 2797 2464 824 Blue 14
8 AM Fri 73 74 SSE 2 3 3212 2792 1152 Blue 17
9 AM Fri 75 78 S 3 4 3609 3300 1660 Blue 21
10 AM Fri 77 82 SSW 4 5 4372 3940 2300 Blue 25
11 AM Fri 80 87 SSW 5 6 6460 5289 3649 Blue 30
12 Noon Fri 81 90 SW 6 8 7967 6331 4691 Blue 33
1 PM Fri 81 90 SW 8 9 7967 6331 4691 Blue 33
2 PM Fri 82 91 WSW 9 11 8158 7017 5377 Blue 34
3 PM Fri 83 90 WSW 9 11 7967 6331 4691 Blue 33
4 PM Fri 83 88 WSW 9 11 7095 5524 3884 Blue 31
5 PM Fri 84 87 WSW 9 10 6460 5289 3649 Blue 30
6 PM Fri 82 83 W 7 8 4816 4080 2440 Blue 26
7 PM Fri 81 81 W 6 6 4231 3579 1939 Blue 24
8 PM Fri 79 79 W 4 4 3950 3393 1753 Blue 22
9 PM Fri 77 77 SW 3 3 3492 3207 1567 Blue 20
10 PM Fri 76 76 S 2 2 3398 3114 1474 Blue 19
11 PM Fri 75 75 SE 1 1 3305 2996 1356 Blue 18

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]