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

Station:

 KVBG

Date/Time:

 11 MAR 2010

Temp/Wind data from:

NOAA Digital Forecast

Time
(Local)		 High
Temp
Puddle
Temp
Wind
 (mph)		 Thermal
Ceiling
(ft)		 Soaring
Ceiling
(ft)		 Above
Launch
(ft)		 Thermal
Type		 Thermal
Index
(F)
7 AM Thu 39 39 NE 12 561 1640 0 Blue 0
8 AM Thu 47 48 NE 12 1949 1738 98 Blue 5
9 AM Thu 55 57 NE 12 4599 3581 1941 Blue 14
10 AM Thu 59 63 NE 7 4880 4688 3048 Blue 20
11 AM Thu 62 67 NE 7 5748 4999 3359 Blue 24
12 Noon Thu 65 70 NE 7 6504 5712 4072 Blue 27
1 PM Thu 67 72 S 2 7003 6214 4574 Blue 29
2 PM Thu 67 71 S 2 6754 5963 4323 Blue 28
3 PM Thu 66 68 S 2 6001 5205 3565 Blue 25
4 PM Thu 65 66 W 9 5493 4858 3218 Blue 23
5 PM Thu 61 61 W 9 4723 4626 2986 Blue 18
6 PM Thu 56 56 W 9 4389 3187 1547 Blue 13
7 PM Thu 52 52 NW 8 2804 2018 378 Blue 9
8 PM Thu 50 50 NW 8 2089 1878 238 Blue 7
9 PM Thu 48 48 NW 8 1949 1738 98 Blue 5
10 PM Thu 47 47 N 4 1878 1668 28 Blue 4
11 PM Thu 46 46 N 4 1808 1640 0 Blue 3
12 Midnight Fri 45 45 N 4 1738 1640 0 Blue 2
1 AM Fri 44 44 N 2 1668 1640 0 Blue 1
2 AM Fri 43 43 N 2 1546 1640 0 Blue 0
3 AM Fri 42 42 N 2 899 1640 0 Blue 0
4 AM Fri 40 40 E 3 561 1640 0 Blue 0
5 AM Fri 40 40 E 3 561 1640 0 Blue 0
6 AM Fri 41 41 E 3 561 1640 0 Blue 0
7 AM Fri 41 41 E 2 561 1640 0 Blue 0
8 AM Fri 49 50 E 2 2089 1878 238 Blue 7
9 AM Fri 55 57 E 2 4599 3581 1941 Blue 14
10 AM Fri 59 62 S 4 4776 4657 3017 Blue 19
11 AM Fri 62 66 S 4 5493 4858 3218 Blue 23
12 Noon Fri 64 68 S 4 6001 5205 3565 Blue 25
1 PM Fri 66 70 SW 7 6504 5712 4072 Blue 27
2 PM Fri 66 69 SW 7 6253 5459 3819 Blue 26
3 PM Fri 66 68 SW 7 6001 5205 3565 Blue 25
4 PM Fri 64 64 SW 7 5011 4719 3079 Blue 21
5 PM Fri 61 61 SW 7 4723 4626 2986 Blue 18
6 PM Fri 57 57 SW 7 4599 3581 1941 Blue 14
7 PM Fri 55 55 W 5 4002 2787 1147 Blue 12
8 PM Fri 53 53 W 5 3209 2088 448 Blue 10
9 PM Fri 52 52 W 5 2804 2018 378 Blue 9
10 PM Fri 51 51 W 4 2160 1948 308 Blue 8
11 PM Fri 50 50 W 4 2089 1878 238 Blue 7
12 Midnight Sat 49 49 W 4 2019 1808 168 Blue 6
1 AM Sat 48 48 NW 2 1949 1738 98 Blue 5
2 AM Sat 47 47 NW 2 1878 1668 28 Blue 4
3 AM Sat 47 47 NW 2 1878 1668 28 Blue 4
4 AM Sat 45 45 N 2 1738 1640 0 Blue 2
5 AM Sat 45 45 N 2 1738 1640 0 Blue 2
6 AM Sat 46 46 N 2 1808 1640 0 Blue 3
7 AM Sat 46 46 SE 1 1808 1640 0 Blue 3
8 AM Sat 51 51 SE 1 2160 1948 308 Blue 8
9 AM Sat 56 57 SE 1 4599 3581 1941 Blue 14
10 AM Sat 58 61 SW 6 4723 4626 2986 Blue 18
11 AM Sat 60 64 SW 6 5011 4719 3079 Blue 21
12 Noon Sat 62 66 SW 6 5493 4858 3218 Blue 23
1 PM Sat 63 66 NW 6 5493 4858 3218 Blue 23
2 PM Sat 63 66 NW 6 5493 4858 3218 Blue 23
3 PM Sat 63 65 NW 6 5237 4768 3128 Blue 22
4 PM Sat 61 62 N 4 4776 4657 3017 Blue 19
5 PM Sat 58 58 N 4 4630 3970 2330 Blue 15
6 PM Sat 54 54 N 4 3609 2158 518 Blue 11
7 PM Sat 52 52 N 4 2804 2018 378 Blue 9
8 PM Sat 50 50 N 4 2089 1878 238 Blue 7
9 PM Sat 49 49 N 4 2019 1808 168 Blue 6
10 PM Sat 47 47 NE 16 1878 1668 28 Blue 4
11 PM Sat 46 46 NE 16 1808 1640 0 Blue 3
12 Midnight Sun 46 46 NE 16 1808 1640 0 Blue 3
1 AM Sun 45 45 NE 16 1738 1640 0 Blue 2
2 AM Sun 44 44 NE 16 1668 1640 0 Blue 1
3 AM Sun 43 43 NE 16 1546 1640 0 Blue 0
4 AM Sun 42 42 NE 16 899 1640 0 Blue 0
5 AM Sun 42 42 NE 16 899 1640 0 Blue 0
6 AM Sun 42 42 NE 16 899 1640 0 Blue 0
7 AM Sun 44 44 NE 16 1668 1640 0 Blue 1
8 AM Sun 52 53 NE 16 3209 2088 448 Blue 10
9 AM Sun 59 61 NE 16 4723 4626 2986 Blue 18
10 AM Sun 63 66 NE 12 5493 4858 3218 Blue 23
11 AM Sun 66 70 NE 12 6504 5712 4072 Blue 27
12 Noon Sun 69 74 NE 12 7523 6710 5070 Blue 31
1 PM Sun 71 75 NE 12 7843 6957 5317 Blue 32
2 PM Sun 71 74 NE 12 7523 6710 5070 Blue 31
3 PM Sun 70 72 NE 12 7003 6214 4574 Blue 29
4 PM Sun 69 70 N 7 6504 5712 4072 Blue 27
5 PM Sun 65 65 N 7 5237 4768 3128 Blue 22
6 PM Sun 60 60 N 7 4692 4595 2955 Blue 17
7 PM Sun 57 57 N 7 4599 3581 1941 Blue 14
8 PM Sun 55 55 N 7 4002 2787 1147 Blue 12
9 PM Sun 54 54 N 7 3609 2158 518 Blue 11
10 PM Sun 52 52 NE 10 2804 2018 378 Blue 9
11 PM Sun 51 51 NE 10 2160 1948 308 Blue 8
12 Midnight Mon 50 50 NE 10 2089 1878 238 Blue 7
1 AM Mon 49 49 NE 10 2019 1808 168 Blue 6
2 AM Mon 48 48 NE 10 1949 1738 98 Blue 5
3 AM Mon 47 47 NE 10 1878 1668 28 Blue 4
4 AM Mon 46 46 NE 14 1808 1640 0 Blue 3
5 AM Mon 46 46 NE 14 1808 1640 0 Blue 3
6 AM Mon 46 46 NE 14 1808 1640 0 Blue 3
7 AM Mon 47 47 NE 14 1878 1668 28 Blue 4
8 AM Mon 57 58 NE 14 4630 3970 2330 Blue 15
9 AM Mon 66 68 NE 14 6001 5205 3565 Blue 25
10 AM Mon 71 75 NE 10 7843 6957 5317 Blue 32
11 AM Mon 74 79 NE 10 9092 8090 6450 Blue 36
12 Noon Mon 78 83 NE 10 10651 9317 7677 Blue 40
1 PM Mon 80 85 NE 10 12846 10149 8509 White 42
2 PM Mon 80 84 NE 10 12646 9618 7978 White 41
3 PM Mon 79 81 NE 10 9774 8709 7069 Blue 38
4 PM Mon 78 79 W 4 9092 8090 6450 Blue 36
5 PM Mon 73 73 W 4 7250 6463 4823 Blue 30
6 PM Mon 67 67 W 4 5748 4999 3359 Blue 24
7 PM Mon 64 64 W 4 5011 4719 3079 Blue 21
8 PM Mon 61 61 W 4 4723 4626 2986 Blue 18
9 PM Mon 59 59 W 4 4661 4353 2713 Blue 16
10 PM Mon 57 57 NE 8 4599 3581 1941 Blue 14
11 PM Mon 56 56 NE 8 4389 3187 1547 Blue 13
12 Midnight Tue 55 55 NE 8 4002 2787 1147 Blue 12
1 AM Tue 54 54 NE 8 3609 2158 518 Blue 11
2 AM Tue 53 53 NE 8 3209 2088 448 Blue 10
3 AM Tue 52 52 NE 8 2804 2018 378 Blue 9
4 AM Tue 50 50 NE 8 2089 1878 238 Blue 7
5 AM Tue 50 50 NE 8 2089 1878 238 Blue 7
6 AM Tue 50 50 NE 8 2089 1878 238 Blue 7
7 AM Tue 51 51 NE 8 2160 1948 308 Blue 8
8 AM Tue 60 61 NE 8 4723 4626 2986 Blue 18
9 AM Tue 68 70 NE 8 6504 5712 4072 Blue 27
10 AM Tue 72 76 NE 4 8160 7203 5563 Blue 33
11 AM Tue 75 80 NE 4 9398 8401 6761 Blue 37
12 Noon Tue 78 83 NE 4 10651 9317 7677 Blue 40
1 PM Tue 80 85 NE 4 12846 10149 8509 White 42
2 PM Tue 80 84 NE 4 12646 9618 7978 White 41
3 PM Tue 80 82 NE 4 10264 9014 7374 Blue 39
4 PM Tue 78 79 SW 4 9092 8090 6450 Blue 36
5 PM Tue 73 73 SW 4 7250 6463 4823 Blue 30
6 PM Tue 68 68 SW 4 6001 5205 3565 Blue 25
7 PM Tue 65 65 SW 4 5237 4768 3128 Blue 22
8 PM Tue 62 62 SW 4 4776 4657 3017 Blue 19
9 PM Tue 60 60 SW 4 4692 4595 2955 Blue 17
10 PM Tue 59 59 N 6 4661 4353 2713 Blue 16
11 PM Tue 58 58 N 6 4630 3970 2330 Blue 15
12 Midnight Wed 56 56 N 6 4389 3187 1547 Blue 13
1 AM Wed 56 56 N 6 4389 3187 1547 Blue 13
2 AM Wed 54 54 N 6 3609 2158 518 Blue 11
3 AM Wed 53 53 N 6 3209 2088 448 Blue 10
4 AM Wed 52 52 NE 8 2804 2018 378 Blue 9
5 AM Wed 52 52 NE 8 2804 2018 378 Blue 9
6 AM Wed 52 52 NE 8 2804 2018 378 Blue 9

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