Detailed Predictions for: Calabasas
Launch Lat, Long, Altitude (f): 34.134575, -118.687689, 1640
LZ Altitude (f): 770
Sounding

Station:

KVBG

Date/Time:

21 SEP 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 Tue 62 62 ENE 1 1 1181 1640 0 Blue 0
1 AM Tue 61 61 ENE 1 1 1181 1640 0 Blue 0
2 AM Tue 59 59 SSE 1 1 1181 1640 0 Blue 0
3 AM Tue 59 59 SSE 1 1 1181 1640 0 Blue 0
4 AM Tue 58 58 SSE 1 1 1181 1640 0 Blue 0
5 AM Tue 57 57 ENE 16 24 1181 1640 0 Blue 0
6 AM Tue 57 57 ENE 16 24 1181 1640 0 Blue 0
7 AM Tue 57 57 ENE 16 24 1181 1640 0 Blue 0
8 AM Tue 62 62 ENE 19 29 1181 1640 0 Blue 0
9 AM Tue 72 73 ENE 19 29 1608 1640 0 Blue 0
10 AM Tue 80 83 ENE 19 29 3454 2866 1226 Blue 7
11 AM Tue 88 92 ENE 8 12 6266 5816 4176 Blue 16
12 Noon Tue 92 97 ENE 8 12 7297 6530 4890 Blue 21
1 PM Tue 95 101 ENE 8 12 8432 7529 5889 Blue 25
2 PM Tue 97 102 SW 5 9 8710 7811 6171 Blue 26
3 PM Tue 97 101 SW 5 9 8432 7529 5889 Blue 25
4 PM Tue 96 98 SW 5 9 7584 6673 5033 Blue 22
5 PM Tue 94 95 S 1 1 6717 6245 4605 Blue 19
6 PM Tue 90 90 S 1 1 5979 5530 3890 Blue 14
7 PM Tue 83 83 S 1 1 3454 2866 1226 Blue 7
8 PM Tue 77 77 S 1 1 1842 1662 22 Blue 1
9 PM Tue 73 73 S 1 1 1608 1640 0 Blue 0
10 PM Tue 71 71 S 1 1 1499 1640 0 Blue 0
11 PM Tue 69 69 NNW 1 1 1390 1640 0 Blue 0
12 Midnight Wed 67 67 NNW 1 1 1281 1640 0 Blue 0
1 AM Wed 65 65 NNW 1 1 1181 1640 0 Blue 0
2 AM Wed 63 63 NW 1 1 1181 1640 0 Blue 0
3 AM Wed 63 63 NW 1 1 1181 1640 0 Blue 0
4 AM Wed 62 62 NW 1 1 1181 1640 0 Blue 0
5 AM Wed 61 61 NW 1 1 1181 1640 0 Blue 0
6 AM Wed 61 61 NW 1 1 1181 1640 0 Blue 0
7 AM Wed 61 61 NW 1 1 1181 1640 0 Blue 0
8 AM Wed 66 66 NW 1 1 1227 1640 0 Blue 0
9 AM Wed 75 76 NW 1 1 1772 1640 0 Blue 0
10 AM Wed 82 85 NW 1 1 4709 3250 1610 Blue 9
11 AM Wed 90 94 WSW 4 5 6553 6102 4462 Blue 18
12 Noon Wed 93 98 WSW 4 5 7584 6673 5033 Blue 22
1 PM Wed 96 101 WSW 4 5 8432 7529 5889 Blue 25
2 PM Wed 98 103 W 6 10 8987 8092 6452 Blue 27
3 PM Wed 98 102 W 6 10 8710 7811 6171 Blue 26
4 PM Wed 97 99 W 6 10 7869 6957 5317 Blue 23
5 PM Wed 95 96 W 6 10 7008 6388 4748 Blue 20
6 PM Wed 91 91 W 6 10 6123 5673 4033 Blue 15
7 PM Wed 83 83 W 6 10 3454 2866 1226 Blue 7
8 PM Wed 77 77 W 6 10 1842 1662 22 Blue 1
9 PM Wed 73 73 W 6 10 1608 1640 0 Blue 0
10 PM Wed 70 70 W 6 10 1445 1640 0 Blue 0
11 PM Wed 68 68 NNE 2 2 1336 1640 0 Blue 0
12 Midnight Thu 66 66 NNE 2 2 1227 1640 0 Blue 0
1 AM Thu 64 64 NNE 2 2 1181 1640 0 Blue 0
2 AM Thu 62 62 NNE 2 2 1181 1640 0 Blue 0
3 AM Thu 62 62 NNE 2 2 1181 1640 0 Blue 0
4 AM Thu 61 61 NNE 2 2 1181 1640 0 Blue 0
5 AM Thu 61 61 NNE 2 2 1181 1640 0 Blue 0
6 AM Thu 60 60 NNE 2 2 1181 1640 0 Blue 0
7 AM Thu 60 60 NNE 2 2 1181 1640 0 Blue 0
8 AM Thu 63 63 NNE 2 2 1181 1640 0 Blue 0
9 AM Thu 70 71 NNE 2 2 1499 1640 0 Blue 0
10 AM Thu 75 77 NNE 2 2 1842 1662 22 Blue 1
11 AM Thu 81 85 SW 5 9 4709 3250 1610 Blue 9
12 Noon Thu 84 89 SW 5 9 5836 5311 3671 Blue 13
1 PM Thu 86 91 SW 5 9 6123 5673 4033 Blue 15
2 PM Thu 87 92 SW 5 9 6266 5816 4176 Blue 16
3 PM Thu 87 90 SW 5 9 5979 5530 3890 Blue 14
4 PM Thu 86 88 SW 5 9 5692 4646 3006 Blue 12
5 PM Thu 85 86 SW 11 17 5343 3442 1802 Blue 10
6 PM Thu 81 81 SW 11 17 3067 2201 561 Blue 5
7 PM Thu 76 76 SW 11 17 1772 1640 0 Blue 0
8 PM Thu 71 71 SW 11 17 1499 1640 0 Blue 0
9 PM Thu 68 68 SW 11 17 1336 1640 0 Blue 0
10 PM Thu 66 66 SW 11 17 1227 1640 0 Blue 0
11 PM Thu 64 64 NE 4 5 1181 1640 0 Blue 0
12 Midnight Fri 63 63 NE 4 5 1181 1640 0 Blue 0
1 AM Fri 61 61 NE 4 5 1181 1640 0 Blue 0
2 AM Fri 60 60 NE 4 5 1181 1640 0 Blue 0
3 AM Fri 60 60 NE 4 5 1181 1640 0 Blue 0
4 AM Fri 59 59 NE 4 5 1181 1640 0 Blue 0
5 AM Fri 58 58 NE 3 4 1181 1640 0 Blue 0
6 AM Fri 58 58 NE 3 4 1181 1640 0 Blue 0
7 AM Fri 58 58 NE 3 4 1181 1640 0 Blue 0
8 AM Fri 62 62 ENE 4 5 1181 1640 0 Blue 0
9 AM Fri 68 69 ENE 4 5 1390 1640 0 Blue 0
10 AM Fri 74 77 ENE 4 5 1842 1662 22 Blue 1
11 AM Fri 80 84 S 6 10 4061 3058 1418 Blue 8
12 Noon Fri 83 88 S 6 10 5692 4646 3006 Blue 12
1 PM Fri 85 90 S 6 10 5979 5530 3890 Blue 14
2 PM Fri 86 91 SSW 13 18 6123 5673 4033 Blue 15
3 PM Fri 86 90 SSW 13 18 5979 5530 3890 Blue 14
4 PM Fri 85 87 SSW 13 18 5548 4009 2369 Blue 11
5 PM Fri 84 85 WSW 11 16 4709 3250 1610 Blue 9
6 PM Fri 80 80 WSW 11 16 2874 1841 201 Blue 4
7 PM Fri 75 75 WSW 11 16 1717 1640 0 Blue 0
8 PM Fri 71 71 WSW 5 8 1499 1640 0 Blue 0
9 PM Fri 67 67 WSW 5 8 1281 1640 0 Blue 0
10 PM Fri 66 66 WSW 5 8 1227 1640 0 Blue 0
11 PM Fri 64 64 N 3 4 1181 1640 0 Blue 0
12 Midnight Sat 63 63 N 3 4 1181 1640 0 Blue 0
1 AM Sat 61 61 N 3 4 1181 1640 0 Blue 0
2 AM Sat 60 60 N 3 4 1181 1640 0 Blue 0
3 AM Sat 60 60 N 3 4 1181 1640 0 Blue 0
4 AM Sat 59 59 N 3 4 1181 1640 0 Blue 0
5 AM Sat 58 58 N 3 4 1181 1640 0 Blue 0
6 AM Sat 58 58 N 3 4 1181 1640 0 Blue 0
7 AM Sat 58 58 N 3 4 1181 1640 0 Blue 0
8 AM Sat 61 61 E 3 4 1181 1640 0 Blue 0
9 AM Sat 68 69 E 3 4 1390 1640 0 Blue 0
10 AM Sat 73 75 E 3 4 1717 1640 0 Blue 0
11 AM Sat 78 81 SSW 6 10 3067 2201 561 Blue 5
12 Noon Sat 81 85 SSW 6 10 4709 3250 1610 Blue 9
1 PM Sat 83 87 SSW 6 10 5548 4009 2369 Blue 11
2 PM Sat 84 88 SW 11 16 5692 4646 3006 Blue 12
3 PM Sat 84 87 SW 11 16 5548 4009 2369 Blue 11
4 PM Sat 83 85 SW 11 16 4709 3250 1610 Blue 9
5 PM Sat 82 83 WSW 11 16 3454 2866 1226 Blue 7
6 PM Sat 79 79 WSW 11 16 2680 1772 132 Blue 3
7 PM Sat 73 73 WSW 11 16 1608 1640 0 Blue 0
8 PM Sat 69 69 W 8 10 1390 1640 0 Blue 0
9 PM Sat 66 66 W 8 10 1227 1640 0 Blue 0
10 PM Sat 64 64 W 8 10 1181 1640 0 Blue 0
11 PM Sat 63 63 W 3 4 1181 1640 0 Blue 0
12 Midnight Sun 61 61 W 3 4 1181 1640 0 Blue 0
1 AM Sun 60 60 W 3 4 1181 1640 0 Blue 0
2 AM Sun 59 59 WSW 3 4 1181 1640 0 Blue 0
3 AM Sun 58 58 WSW 3 4 1181 1640 0 Blue 0
4 AM Sun 58 58 WSW 3 4 1181 1640 0 Blue 0
5 AM Sun 57 57 E 3 4 1181 1640 0 Blue 0
6 AM Sun 57 57 E 3 4 1181 1640 0 Blue 0
7 AM Sun 57 57 E 3 4 1181 1640 0 Blue 0
8 AM Sun 60 60 SSE 3 4 1181 1640 0 Blue 0
9 AM Sun 67 68 SSE 3 4 1336 1640 0 Blue 0
10 AM Sun 72 74 SSE 3 4 1662 1640 0 Blue 0
11 AM Sun 77 81 S 5 9 3067 2201 561 Blue 5
12 Noon Sun 80 84 S 5 9 4061 3058 1418 Blue 8
1 PM Sun 82 87 S 5 9 5548 4009 2369 Blue 11
2 PM Sun 83 87 SW 12 17 5548 4009 2369 Blue 11
3 PM Sun 83 86 SW 12 17 5343 3442 1802 Blue 10
4 PM Sun 82 84 SW 12 17 4061 3058 1418 Blue 8
5 PM Sun 81 82 WSW 12 16 3261 2673 1033 Blue 6
6 PM Sun 77 77 WSW 12 16 1842 1662 22 Blue 1
7 PM Sun 72 72 WSW 12 16 1554 1640 0 Blue 0
8 PM Sun 68 68 WSW 6 9 1336 1640 0 Blue 0
9 PM Sun 64 64 WSW 6 9 1181 1640 0 Blue 0
10 PM Sun 63 63 WSW 6 9 1181 1640 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 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]