Detailed Predictions for: Big Sur
Launch Altitude (f): 3200
LZ Altitude (f): 60
Sounding

Station:

 KOAK

Date/Time:

 4 FEB 2012

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)
4 AM Sat 51 41 E 8 2612 3200 0 Blue 0
5 AM Sat 51 41 E 8 2612 3200 0 Blue 0
6 AM Sat 50 40 E 8 2612 3200 0 Blue 0
7 AM Sat 49 39 SE 8 2612 3200 0 Blue 0
8 AM Sat 52 42 SE 8 2612 3200 0 Blue 0
9 AM Sat 56 46 SE 8 2612 3200 0 Blue 0
10 AM Sat 57 48 SE 7 3087 3200 0 Blue 0
11 AM Sat 58 50 SE 7 3887 3200 0 Blue 1
12 Noon Sat 59 52 SE 7 4677 3442 242 Blue 3
1 PM Sat 58 51 SW 7 4315 3200 0 Blue 2
2 PM Sat 59 51 SW 7 4315 3200 0 Blue 2
3 PM Sat 60 51 SW 7 4315 3200 0 Blue 2
4 PM Sat 60 50 SW 2 3887 3200 0 Blue 1
5 PM Sat 58 48 SW 2 3087 3200 0 Blue 0
6 PM Sat 55 45 SW 2 2612 3200 0 Blue 0
7 PM Sat 55 45 NE 6 2612 3200 0 Blue 0
8 PM Sat 54 44 NE 6 2612 3200 0 Blue 0
9 PM Sat 55 45 NE 6 2612 3200 0 Blue 0
10 PM Sat 54 44 NE 9 2612 3200 0 Blue 0
11 PM Sat 54 44 NE 9 2612 3200 0 Blue 0
12 Midnight Sun 54 44 NE 9 2612 3200 0 Blue 0
1 AM Sun 54 44 E 12 2612 3200 0 Blue 0
2 AM Sun 53 43 E 12 2612 3200 0 Blue 0
3 AM Sun 54 44 E 12 2612 3200 0 Blue 0
4 AM Sun 53 43 E 14 2612 3200 0 Blue 0
5 AM Sun 53 43 E 14 2612 3200 0 Blue 0
6 AM Sun 52 42 E 14 2612 3200 0 Blue 0
7 AM Sun 51 41 E 14 2612 3200 0 Blue 0
8 AM Sun 54 44 E 14 2612 3200 0 Blue 0
9 AM Sun 58 48 E 14 3087 3200 0 Blue 0
10 AM Sun 59 50 E 13 3887 3200 0 Blue 1
11 AM Sun 59 51 E 13 4315 3200 0 Blue 2
12 Noon Sun 61 53 E 13 4857 3872 672 Blue 4
1 PM Sun 59 51 SE 9 4315 3200 0 Blue 2
2 PM Sun 61 52 SE 9 4677 3442 242 Blue 3
3 PM Sun 62 53 SE 9 4857 3872 672 Blue 4
4 PM Sun 62 52 E 5 4677 3442 242 Blue 3
5 PM Sun 60 50 E 5 3887 3200 0 Blue 1
6 PM Sun 55 45 E 5 2612 3200 0 Blue 0
7 PM Sun 56 46 E 5 2612 3200 0 Blue 0
8 PM Sun 54 44 E 5 2612 3200 0 Blue 0
9 PM Sun 55 45 E 5 2612 3200 0 Blue 0
10 PM Sun 55 45 E 9 2612 3200 0 Blue 0
11 PM Sun 54 44 E 9 2612 3200 0 Blue 0
12 Midnight Mon 55 45 E 9 2612 3200 0 Blue 0
1 AM Mon 54 44 E 9 2612 3200 0 Blue 0
2 AM Mon 53 43 E 9 2612 3200 0 Blue 0
3 AM Mon 54 44 E 9 2612 3200 0 Blue 0
4 AM Mon 53 43 SE 9 2612 3200 0 Blue 0
5 AM Mon 53 43 SE 9 2612 3200 0 Blue 0
6 AM Mon 52 42 SE 9 2612 3200 0 Blue 0
7 AM Mon 51 41 SE 9 2612 3200 0 Blue 0
8 AM Mon 53 43 SE 9 2612 3200 0 Blue 0
9 AM Mon 56 46 SE 9 2612 3200 0 Blue 0
10 AM Mon 57 48 S 13 3087 3200 0 Blue 0
11 AM Mon 57 48 S 13 3087 3200 0 Blue 0
12 Noon Mon 58 50 S 13 3887 3200 0 Blue 1
1 PM Mon 57 49 S 13 3452 3200 0 Blue 0
2 PM Mon 58 49 S 13 3452 3200 0 Blue 0
3 PM Mon 59 49 S 13 3452 3200 0 Blue 0
4 PM Mon 59 49 S 10 3452 3200 0 Blue 0
5 PM Mon 56 46 S 10 2612 3200 0 Blue 0
6 PM Mon 50 40 S 10 2612 3200 0 Blue 0
7 PM Mon 51 41 S 10 2612 3200 0 Blue 0
8 PM Mon 48 38 S 10 2612 3200 0 Blue 0
9 PM Mon 50 40 S 10 2612 3200 0 Blue 0
10 PM Mon 49 39 SE 21 2612 3200 0 Blue 0
11 PM Mon 49 39 SE 21 2612 3200 0 Blue 0
12 Midnight Tue 49 39 SE 21 2612 3200 0 Blue 0
1 AM Tue 48 38 SE 21 2612 3200 0 Blue 0
2 AM Tue 47 37 SE 21 2612 3200 0 Blue 0
3 AM Tue 48 38 SE 21 2612 3200 0 Blue 0
4 AM Tue 48 38 SE 20 2612 3200 0 Blue 0
5 AM Tue 47 37 SE 20 2612 3200 0 Blue 0
6 AM Tue 45 35 SE 20 2612 3200 0 Blue 0
7 AM Tue 45 35 SE 20 2612 3200 0 Blue 0
8 AM Tue 47 37 SE 20 2612 3200 0 Blue 0
9 AM Tue 50 40 SE 20 2612 3200 0 Blue 0
10 AM Tue 51 41 S 15 2612 3200 0 Blue 0
11 AM Tue 52 42 S 15 2612 3200 0 Blue 0
12 Noon Tue 53 43 S 15 2612 3200 0 Blue 0
1 PM Tue 52 42 S 15 2612 3200 0 Blue 0
2 PM Tue 53 43 S 15 2612 3200 0 Blue 0
3 PM Tue 54 44 S 15 2612 3200 0 Blue 0
4 PM Tue 54 44 SW 10 2612 3200 0 Blue 0
5 PM Tue 52 42 SW 10 2612 3200 0 Blue 0
6 PM Tue 47 37 SW 10 2612 3200 0 Blue 0
7 PM Tue 47 37 SW 10 2612 3200 0 Blue 0
8 PM Tue 45 35 SW 10 2612 3200 0 Blue 0
9 PM Tue 47 37 SW 10 2612 3200 0 Blue 0
10 PM Tue 46 36 NW 5 2612 3200 0 Blue 0
11 PM Tue 46 36 NW 5 2612 3200 0 Blue 0
12 Midnight Wed 46 36 NW 5 2612 3200 0 Blue 0
1 AM Wed 45 35 NW 5 2612 3200 0 Blue 0
2 AM Wed 44 34 NW 5 2612 3200 0 Blue 0
3 AM Wed 45 35 NW 5 2612 3200 0 Blue 0
4 AM Wed 45 35 N 8 2612 3200 0 Blue 0
5 AM Wed 44 34 N 8 2612 3200 0 Blue 0
6 AM Wed 43 33 N 8 2612 3200 0 Blue 0
7 AM Wed 42 32 N 8 2612 3200 0 Blue 0
8 AM Wed 46 36 N 8 2612 3200 0 Blue 0
9 AM Wed 51 41 N 8 2612 3200 0 Blue 0
10 AM Wed 52 43 N 9 2612 3200 0 Blue 0
11 AM Wed 53 44 N 9 2612 3200 0 Blue 0
12 Noon Wed 55 47 N 9 2778 3200 0 Blue 0
1 PM Wed 53 44 N 9 2612 3200 0 Blue 0
2 PM Wed 54 45 N 9 2612 3200 0 Blue 0
3 PM Wed 56 46 N 9 2612 3200 0 Blue 0
4 PM Wed 56 46 N 12 2612 3200 0 Blue 0
5 PM Wed 54 44 N 12 2612 3200 0 Blue 0
6 PM Wed 51 41 N 12 2612 3200 0 Blue 0
7 PM Wed 51 41 N 12 2612 3200 0 Blue 0
8 PM Wed 49 39 N 12 2612 3200 0 Blue 0
9 PM Wed 50 40 N 12 2612 3200 0 Blue 0
10 PM Wed 50 40 N 9 2612 3200 0 Blue 0
11 PM Wed 50 40 N 9 2612 3200 0 Blue 0
12 Midnight Thu 50 40 N 9 2612 3200 0 Blue 0
1 AM Thu 50 40 N 9 2612 3200 0 Blue 0
2 AM Thu 49 39 N 9 2612 3200 0 Blue 0
3 AM Thu 50 40 N 9 2612 3200 0 Blue 0
4 AM Thu 49 39 NE 8 2612 3200 0 Blue 0
5 AM Thu 49 39 NE 8 2612 3200 0 Blue 0
6 AM Thu 48 38 NE 8 2612 3200 0 Blue 0
7 AM Thu 47 37 NE 8 2612 3200 0 Blue 0
8 AM Thu 51 41 NE 8 2612 3200 0 Blue 0
9 AM Thu 56 47 NE 8 2778 3200 0 Blue 0
10 AM Thu 58 50 NE 6 3887 3200 0 Blue 1
11 AM Thu 59 51 NE 6 4315 3200 0 Blue 2
12 Noon Thu 60 53 NE 6 4857 3872 672 Blue 4
1 PM Thu 59 52 NE 6 4677 3442 242 Blue 3
2 PM Thu 60 52 NE 6 4677 3442 242 Blue 3
3 PM Thu 62 53 NE 6 4857 3872 672 Blue 4
4 PM Thu 62 52 N 6 4677 3442 242 Blue 3
5 PM Thu 59 49 N 6 3452 3200 0 Blue 0
6 PM Thu 55 45 N 6 2612 3200 0 Blue 0
7 PM Thu 55 45 N 6 2612 3200 0 Blue 0
8 PM Thu 53 43 N 6 2612 3200 0 Blue 0
9 PM Thu 55 45 N 6 2612 3200 0 Blue 0
10 PM Thu 54 44 E 6 2612 3200 0 Blue 0
11 PM Thu 54 44 E 6 2612 3200 0 Blue 0
12 Midnight Fri 54 44 E 6 2612 3200 0 Blue 0
1 AM Fri 53 43 E 6 2612 3200 0 Blue 0
2 AM Fri 52 42 E 6 2612 3200 0 Blue 0
3 AM Fri 54 44 E 6 2612 3200 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