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

Station:

 KOAK

Date/Time:

 19 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)
5 AM Fri 58 48 NE 8 2621 3200 0 Blue 0
6 AM Fri 59 49 NE 8 2621 3200 0 Blue 0
7 AM Fri 58 48 NE 8 2621 3200 0 Blue 0
8 AM Fri 57 47 NE 4 2621 3200 0 Blue 0
9 AM Fri 59 50 NE 4 2621 3200 0 Blue 0
10 AM Fri 63 55 NE 4 2621 3200 0 Blue 0
11 AM Fri 64 58 S 4 2621 3200 0 Blue 0
12 Noon Fri 65 60 S 4 2621 3200 0 Blue 0
1 PM Fri 67 63 S 4 2621 3200 0 Blue 0
2 PM Fri 66 61 SW 5 2621 3200 0 Blue 0
3 PM Fri 68 62 SW 5 2621 3200 0 Blue 0
4 PM Fri 68 61 SW 5 2621 3200 0 Blue 0
5 PM Fri 69 60 W 4 2621 3200 0 Blue 0
6 PM Fri 66 56 W 4 2621 3200 0 Blue 0
7 PM Fri 61 51 W 4 2621 3200 0 Blue 0
8 PM Fri 59 49 NW 3 2621 3200 0 Blue 0
9 PM Fri 60 50 NW 3 2621 3200 0 Blue 0
10 PM Fri 59 49 NW 3 2621 3200 0 Blue 0
11 PM Fri 58 48 N 3 2621 3200 0 Blue 0
12 Midnight Sat 58 48 N 3 2621 3200 0 Blue 0
1 AM Sat 57 47 N 3 2621 3200 0 Blue 0
2 AM Sat 58 48 NE 2 2621 3200 0 Blue 0
3 AM Sat 56 46 NE 2 2621 3200 0 Blue 0
4 AM Sat 56 46 NE 2 2621 3200 0 Blue 0
5 AM Sat 57 47 E 3 2621 3200 0 Blue 0
6 AM Sat 57 47 E 3 2621 3200 0 Blue 0
7 AM Sat 55 45 E 3 2621 3200 0 Blue 0
8 AM Sat 55 45 SE 2 2621 3200 0 Blue 0
9 AM Sat 56 47 SE 2 2621 3200 0 Blue 0
10 AM Sat 60 52 SE 2 2621 3200 0 Blue 0
11 AM Sat 60 54 SW 5 2621 3200 0 Blue 0
12 Noon Sat 61 56 SW 5 2621 3200 0 Blue 0
1 PM Sat 63 59 SW 5 2621 3200 0 Blue 0
2 PM Sat 62 57 SW 5 2621 3200 0 Blue 0
3 PM Sat 64 58 SW 5 2621 3200 0 Blue 0
4 PM Sat 64 57 SW 5 2621 3200 0 Blue 0
5 PM Sat 65 56 W 4 2621 3200 0 Blue 0
6 PM Sat 62 52 W 4 2621 3200 0 Blue 0
7 PM Sat 58 48 W 4 2621 3200 0 Blue 0
8 PM Sat 56 46 W 4 2621 3200 0 Blue 0
9 PM Sat 56 46 W 4 2621 3200 0 Blue 0
10 PM Sat 56 46 W 4 2621 3200 0 Blue 0
11 PM Sat 55 45 NW 2 2621 3200 0 Blue 0
12 Midnight Sun 55 45 NW 2 2621 3200 0 Blue 0
1 AM Sun 54 44 NW 2 2621 3200 0 Blue 0
2 AM Sun 55 45 NW 2 2621 3200 0 Blue 0
3 AM Sun 53 43 NW 2 2621 3200 0 Blue 0
4 AM Sun 53 43 NW 2 2621 3200 0 Blue 0
5 AM Sun 54 44 S 1 2621 3200 0 Blue 0
6 AM Sun 54 44 S 1 2621 3200 0 Blue 0
7 AM Sun 53 43 S 1 2621 3200 0 Blue 0
8 AM Sun 52 42 S 1 2621 3200 0 Blue 0
9 AM Sun 54 45 S 1 2621 3200 0 Blue 0
10 AM Sun 58 50 S 1 2621 3200 0 Blue 0
11 AM Sun 59 53 W 4 2621 3200 0 Blue 0
12 Noon Sun 59 54 W 4 2621 3200 0 Blue 0
1 PM Sun 61 56 W 4 2621 3200 0 Blue 0
2 PM Sun 61 56 W 4 2621 3200 0 Blue 0
3 PM Sun 63 57 W 4 2621 3200 0 Blue 0
4 PM Sun 63 55 W 4 2621 3200 0 Blue 0
5 PM Sun 64 55 NW 4 2621 3200 0 Blue 0
6 PM Sun 61 51 NW 4 2621 3200 0 Blue 0
7 PM Sun 56 46 NW 4 2621 3200 0 Blue 0
8 PM Sun 53 43 NW 4 2621 3200 0 Blue 0
9 PM Sun 54 44 NW 4 2621 3200 0 Blue 0
10 PM Sun 54 44 NW 4 2621 3200 0 Blue 0
11 PM Sun 53 43 NW 4 2621 3200 0 Blue 0
12 Midnight Mon 52 42 NW 4 2621 3200 0 Blue 0
1 AM Mon 51 41 NW 4 2621 3200 0 Blue 0
2 AM Mon 52 42 NW 4 2621 3200 0 Blue 0
3 AM Mon 51 41 NW 4 2621 3200 0 Blue 0
4 AM Mon 50 40 NW 4 2621 3200 0 Blue 0
5 AM Mon 51 41 N 4 2621 3200 0 Blue 0
6 AM Mon 51 41 N 4 2621 3200 0 Blue 0
7 AM Mon 50 40 N 4 2621 3200 0 Blue 0
8 AM Mon 49 39 N 4 2621 3200 0 Blue 0
9 AM Mon 51 41 N 4 2621 3200 0 Blue 0
10 AM Mon 55 46 N 4 2621 3200 0 Blue 0
11 AM Mon 56 48 N 10 2621 3200 0 Blue 0
12 Noon Mon 57 50 N 10 2621 3200 0 Blue 0
1 PM Mon 59 53 N 10 2621 3200 0 Blue 0
2 PM Mon 58 51 N 10 2621 3200 0 Blue 0
3 PM Mon 60 53 N 10 2621 3200 0 Blue 0
4 PM Mon 61 53 N 10 2621 3200 0 Blue 0
5 PM Mon 61 52 N 16 2621 3200 0 Blue 0
6 PM Mon 58 48 N 16 2621 3200 0 Blue 0
7 PM Mon 53 43 N 16 2621 3200 0 Blue 0
8 PM Mon 51 41 N 16 2621 3200 0 Blue 0
9 PM Mon 52 42 N 16 2621 3200 0 Blue 0
10 PM Mon 52 42 N 16 2621 3200 0 Blue 0
11 PM Mon 50 40 N 13 2621 3200 0 Blue 0
12 Midnight Tue 50 40 N 13 2621 3200 0 Blue 0
1 AM Tue 49 39 N 13 2621 3200 0 Blue 0
2 AM Tue 50 40 N 13 2621 3200 0 Blue 0
3 AM Tue 49 39 N 13 2621 3200 0 Blue 0
4 AM Tue 48 38 N 13 2621 3200 0 Blue 0
5 AM Tue 49 39 N 16 2621 3200 0 Blue 0
6 AM Tue 49 39 N 16 2621 3200 0 Blue 0
7 AM Tue 48 38 N 16 2621 3200 0 Blue 0
8 AM Tue 47 37 N 16 2621 3200 0 Blue 0
9 AM Tue 49 40 N 16 2621 3200 0 Blue 0
10 AM Tue 54 46 N 16 2621 3200 0 Blue 0
11 AM Tue 55 48 N 14 2621 3200 0 Blue 0
12 Noon Tue 56 50 N 14 2621 3200 0 Blue 0
1 PM Tue 58 52 N 14 2621 3200 0 Blue 0
2 PM Tue 58 52 N 14 2621 3200 0 Blue 0
3 PM Tue 60 53 N 14 2621 3200 0 Blue 0
4 PM Tue 61 53 N 14 2621 3200 0 Blue 0
5 PM Tue 61 52 N 17 2621 3200 0 Blue 0
6 PM Tue 59 49 N 17 2621 3200 0 Blue 0
7 PM Tue 54 44 N 17 2621 3200 0 Blue 0
8 PM Tue 51 41 N 17 2621 3200 0 Blue 0
9 PM Tue 52 42 N 17 2621 3200 0 Blue 0
10 PM Tue 52 42 N 17 2621 3200 0 Blue 0
11 PM Tue 51 41 N 13 2621 3200 0 Blue 0
12 Midnight Wed 50 40 N 13 2621 3200 0 Blue 0
1 AM Wed 49 39 N 13 2621 3200 0 Blue 0
2 AM Wed 51 41 N 13 2621 3200 0 Blue 0
3 AM Wed 49 39 N 13 2621 3200 0 Blue 0
4 AM Wed 49 39 N 13 2621 3200 0 Blue 0
5 AM Wed 49 39 N 6 2621 3200 0 Blue 0
6 AM Wed 49 39 N 6 2621 3200 0 Blue 0
7 AM Wed 48 38 N 6 2621 3200 0 Blue 0
8 AM Wed 47 37 N 6 2621 3200 0 Blue 0
9 AM Wed 50 41 N 6 2621 3200 0 Blue 0
10 AM Wed 55 47 N 6 2621 3200 0 Blue 0
11 AM Wed 56 49 S 4 2621 3200 0 Blue 0
12 Noon Wed 57 51 S 4 2621 3200 0 Blue 0
1 PM Wed 59 53 S 4 2621 3200 0 Blue 0
2 PM Wed 58 52 S 4 2621 3200 0 Blue 0
3 PM Wed 61 54 S 4 2621 3200 0 Blue 0
4 PM Wed 61 53 S 4 2621 3200 0 Blue 0
5 PM Wed 62 53 S 5 2621 3200 0 Blue 0
6 PM Wed 59 49 S 5 2621 3200 0 Blue 0
7 PM Wed 55 45 S 5 2621 3200 0 Blue 0
8 PM Wed 53 43 S 5 2621 3200 0 Blue 0
9 PM Wed 54 44 S 5 2621 3200 0 Blue 0
10 PM Wed 54 44 S 5 2621 3200 0 Blue 0
11 PM Wed 53 43 SE 2 2621 3200 0 Blue 0
12 Midnight Thu 52 42 SE 2 2621 3200 0 Blue 0
1 AM Thu 51 41 SE 2 2621 3200 0 Blue 0
2 AM Thu 52 42 SE 2 2621 3200 0 Blue 0
3 AM Thu 51 41 SE 2 2621 3200 0 Blue 0
4 AM Thu 50 40 SE 2 2621 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