Detailed Predictions for: Calabasas
Launch Altitude (f): 1640
LZ Altitude (f): 770
Sounding

Station:

KVBG

Date/Time:

24 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 Sat 61 61 E 5 1789 1640 0 Blue 1
6 AM Sat 59 59 E 5 1460 1640 0 Blue 0
7 AM Sat 59 59 E 5 1460 1640 0 Blue 0
8 AM Sat 64 64 E 5 1976 1788 148 Blue 4
9 AM Sat 70 72 E 5 2351 2209 569 Blue 12
10 AM Sat 76 80 E 5 2835 2628 988 Blue 20
11 AM Sat 81 86 S 5 3722 3254 1614 Blue 26
12 Noon Sat 85 92 S 5 5622 4585 2945 Blue 32
1 PM Sat 87 94 S 5 7314 5102 3462 Blue 34
2 PM Sat 88 95 S 10 7742 5563 3923 Blue 35
3 PM Sat 89 95 S 10 7742 5563 3923 Blue 35
4 PM Sat 89 93 S 10 6080 4784 3144 Blue 33
5 PM Sat 87 89 S 10 4604 3686 2046 Blue 29
6 PM Sat 84 84 S 10 3378 2923 1283 Blue 24
7 PM Sat 80 80 S 10 2835 2628 988 Blue 20
8 PM Sat 75 75 S 12 2494 2350 710 Blue 15
9 PM Sat 71 71 S 12 2304 2162 522 Blue 11
10 PM Sat 69 69 S 12 2210 2068 428 Blue 9
11 PM Sat 67 67 E 2 2116 1975 335 Blue 7
12 Midnight Sun 66 66 E 2 2069 1928 288 Blue 6
1 AM Sun 65 65 E 2 2022 1874 234 Blue 5
2 AM Sun 64 64 SE 3 1976 1788 148 Blue 4
3 AM Sun 64 64 SE 3 1976 1788 148 Blue 4
4 AM Sun 63 63 SE 3 1929 1684 44 Blue 3
5 AM Sun 62 62 SE 2 1875 1640 0 Blue 2
6 AM Sun 61 61 SE 2 1789 1640 0 Blue 1
7 AM Sun 61 61 SE 2 1789 1640 0 Blue 1
8 AM Sun 66 66 E 2 2069 1928 288 Blue 6
9 AM Sun 73 75 E 2 2494 2350 710 Blue 15
10 AM Sun 79 83 E 2 3261 2832 1192 Blue 23
11 AM Sun 85 90 SW 6 4805 4180 2540 Blue 30
12 Noon Sun 88 95 SW 6 7742 5563 3923 Blue 35
1 PM Sun 91 98 SW 6 8064 7708 6068 Blue 38
2 PM Sun 92 99 W 10 8168 7836 6196 Blue 39
3 PM Sun 92 98 W 10 8064 7708 6068 Blue 38
4 PM Sun 93 97 W 10 7961 6844 5204 Blue 37
5 PM Sun 91 93 W 10 6080 4784 3144 Blue 33
6 PM Sun 88 88 W 10 4404 3488 1848 Blue 28
7 PM Sun 83 83 W 10 3261 2832 1192 Blue 23
8 PM Sun 78 78 W 7 2699 2492 852 Blue 18
9 PM Sun 73 73 W 7 2398 2256 616 Blue 13
10 PM Sun 71 71 W 7 2304 2162 522 Blue 11
11 PM Sun 69 69 S 2 2210 2068 428 Blue 9
12 Midnight Mon 69 69 S 2 2210 2068 428 Blue 9
1 AM Mon 68 68 S 2 2163 2022 382 Blue 8
2 AM Mon 66 66 S 2 2069 1928 288 Blue 6
3 AM Mon 66 66 S 2 2069 1928 288 Blue 6
4 AM Mon 65 65 S 2 2022 1874 234 Blue 5
5 AM Mon 64 64 S 2 1976 1788 148 Blue 4
6 AM Mon 63 63 S 2 1929 1684 44 Blue 3
7 AM Mon 63 63 S 2 1929 1684 44 Blue 3
8 AM Mon 68 68 S 2 2163 2022 382 Blue 8
9 AM Mon 74 75 S 2 2494 2350 710 Blue 15
10 AM Mon 79 82 S 2 3112 2764 1124 Blue 22
11 AM Mon 85 89 SW 6 4604 3686 2046 Blue 29
12 Noon Mon 88 92 SW 6 5622 4585 2945 Blue 32
1 PM Mon 90 95 SW 6 7742 5563 3923 Blue 35
2 PM Mon 91 95 SW 6 7742 5563 3923 Blue 35
3 PM Mon 92 96 SW 6 7857 6015 4375 Blue 36
4 PM Mon 92 94 SW 6 7314 5102 3462 Blue 34
5 PM Mon 90 91 SW 6 5156 4386 2746 Blue 31
6 PM Mon 87 87 SW 6 4203 3371 1731 Blue 27
7 PM Mon 82 82 SW 6 3112 2764 1124 Blue 22
8 PM Mon 77 77 SW 6 2630 2443 803 Blue 17
9 PM Mon 72 72 SW 6 2351 2209 569 Blue 12
10 PM Mon 70 70 SW 6 2257 2115 475 Blue 10
11 PM Mon 68 68 E 1 2163 2022 382 Blue 8
12 Midnight Tue 68 68 E 1 2163 2022 382 Blue 8
1 AM Tue 67 67 E 1 2116 1975 335 Blue 7
2 AM Tue 65 65 E 1 2022 1874 234 Blue 5
3 AM Tue 65 65 E 1 2022 1874 234 Blue 5
4 AM Tue 64 64 E 1 1976 1788 148 Blue 4
5 AM Tue 63 63 E 1 1929 1684 44 Blue 3
6 AM Tue 62 62 E 1 1875 1640 0 Blue 2
7 AM Tue 62 62 E 1 1875 1640 0 Blue 2
8 AM Tue 67 67 E 1 2116 1975 335 Blue 7
9 AM Tue 73 75 E 1 2494 2350 710 Blue 15
10 AM Tue 79 83 E 1 3261 2832 1192 Blue 23
11 AM Tue 84 90 SW 8 4805 4180 2540 Blue 30
12 Noon Tue 88 95 SW 8 7742 5563 3923 Blue 35
1 PM Tue 90 98 SW 8 8064 7708 6068 Blue 38
2 PM Tue 91 98 SW 8 8064 7708 6068 Blue 38
3 PM Tue 92 98 SW 8 8064 7708 6068 Blue 38
4 PM Tue 92 96 SW 8 7857 6015 4375 Blue 36
5 PM Tue 90 92 SW 8 5622 4585 2945 Blue 32
6 PM Tue 87 88 SW 8 4404 3488 1848 Blue 28
7 PM Tue 82 82 SW 8 3112 2764 1124 Blue 22
8 PM Tue 76 76 SW 8 2562 2396 756 Blue 16
9 PM Tue 72 72 SW 8 2351 2209 569 Blue 12
10 PM Tue 69 69 SW 8 2210 2068 428 Blue 9
11 PM Tue 68 68 SE 5 2163 2022 382 Blue 8
12 Midnight Wed 67 67 SE 5 2116 1975 335 Blue 7
1 AM Wed 66 66 SE 5 2069 1928 288 Blue 6
2 AM Wed 64 64 SE 5 1976 1788 148 Blue 4
3 AM Wed 64 64 SE 5 1976 1788 148 Blue 4
4 AM Wed 63 63 SE 5 1929 1684 44 Blue 3
5 AM Wed 63 63 SE 5 1929 1684 44 Blue 3
6 AM Wed 61 61 SE 5 1789 1640 0 Blue 1
7 AM Wed 61 61 SE 5 1789 1640 0 Blue 1
8 AM Wed 66 66 SE 5 2069 1928 288 Blue 6
9 AM Wed 72 74 SE 5 2445 2303 663 Blue 14
10 AM Wed 78 82 SE 5 3112 2764 1124 Blue 22
11 AM Wed 83 89 SW 10 4604 3686 2046 Blue 29
12 Noon Wed 87 94 SW 10 7314 5102 3462 Blue 34
1 PM Wed 89 97 SW 10 7961 6844 5204 Blue 37
2 PM Wed 90 97 SW 10 7961 6844 5204 Blue 37
3 PM Wed 91 97 SW 10 7961 6844 5204 Blue 37
4 PM Wed 91 95 SW 10 7742 5563 3923 Blue 35
5 PM Wed 89 91 SW 10 5156 4386 2746 Blue 31
6 PM Wed 86 87 SW 10 4203 3371 1731 Blue 27
7 PM Wed 81 81 SW 10 2931 2696 1056 Blue 21
8 PM Wed 75 75 SW 10 2494 2350 710 Blue 15
9 PM Wed 71 71 SW 10 2304 2162 522 Blue 11
10 PM Wed 68 68 SW 10 2163 2022 382 Blue 8
11 PM Wed 67 67 SE 3 2116 1975 335 Blue 7
12 Midnight Thu 66 66 SE 3 2069 1928 288 Blue 6
1 AM Thu 65 65 SE 3 2022 1874 234 Blue 5
2 AM Thu 63 63 SE 3 1929 1684 44 Blue 3
3 AM Thu 63 63 SE 3 1929 1684 44 Blue 3
4 AM Thu 62 62 SE 3 1875 1640 0 Blue 2
5 AM Thu 62 62 SE 3 1875 1640 0 Blue 2
6 AM Thu 60 60 SE 3 1685 1640 0 Blue 0
7 AM Thu 60 60 SE 3 1685 1640 0 Blue 0
8 AM Thu 66 66 SE 3 2069 1928 288 Blue 6
9 AM Thu 72 74 SE 3 2445 2303 663 Blue 14
10 AM Thu 79 83 SE 3 3261 2832 1192 Blue 23
11 AM Thu 85 91 W 9 5156 4386 2746 Blue 31
12 Noon Thu 88 95 W 9 7742 5563 3923 Blue 35
1 PM Thu 91 99 W 9 8168 7836 6196 Blue 39
2 PM Thu 92 99 W 9 8168 7836 6196 Blue 39
3 PM Thu 92 98 W 9 8064 7708 6068 Blue 38
4 PM Thu 93 97 W 9 7961 6844 5204 Blue 37
5 PM Thu 91 93 W 9 6080 4784 3144 Blue 33
6 PM Thu 88 88 W 9 4404 3488 1848 Blue 28
7 PM Thu 83 83 W 9 3261 2832 1192 Blue 23
8 PM Thu 77 77 W 9 2630 2443 803 Blue 17
9 PM Thu 73 73 W 9 2398 2256 616 Blue 13
10 PM Thu 70 70 W 9 2257 2115 475 Blue 10
11 PM Thu 69 69 S 3 2210 2068 428 Blue 9
12 Midnight Fri 68 68 S 3 2163 2022 382 Blue 8
1 AM Fri 67 67 S 3 2116 1975 335 Blue 7
2 AM Fri 65 65 S 3 2022 1874 234 Blue 5
3 AM Fri 65 65 S 3 2022 1874 234 Blue 5
4 AM Fri 64 64 S 3 1976 1788 148 Blue 4

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