Detailed Predictions for: Big Sur
Launch Lat, Long, Altitude (f): 36.0, -121.47, 3200
LZ Altitude (f): 60
Sounding

Station:

KOAK

Date/Time:

12 MAY 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 Wed 60 50 ENE 2 2 2566 3200 0 Blue 0
1 AM Wed 59 49 ENE 2 3 2566 3200 0 Blue 0
2 AM Wed 58 48 ENE 3 4 2566 3200 0 Blue 0
3 AM Wed 58 48 ENE 3 4 2566 3200 0 Blue 0
4 AM Wed 58 48 ENE 3 4 2566 3200 0 Blue 0
5 AM Wed 57 47 ENE 4 5 2566 3200 0 Blue 0
6 AM Wed 61 51 ENE 4 5 2566 3200 0 Blue 0
7 AM Wed 60 50 ENE 5 6 2566 3200 0 Blue 0
8 AM Wed 63 54 E 4 5 2566 3200 0 Blue 0
9 AM Wed 64 56 E 3 4 2566 3200 0 Blue 0
10 AM Wed 65 59 ESE 3 4 2566 3200 0 Blue 0
11 AM Wed 64 60 SE 3 4 2566 3200 0 Blue 0
12 Noon Wed 65 62 S 3 4 2566 3200 0 Blue 0
1 PM Wed 65 62 SSW 4 4 2566 3200 0 Blue 0
2 PM Wed 66 63 SSW 4 4 2566 3200 0 Blue 0
3 PM Wed 66 62 SSW 3 4 2566 3200 0 Blue 0
4 PM Wed 66 60 WSW 3 4 2566 3200 0 Blue 0
5 PM Wed 66 58 W 3 4 2566 3200 0 Blue 0
6 PM Wed 66 57 W 4 4 2566 3200 0 Blue 0
7 PM Wed 65 55 WNW 3 4 2566 3200 0 Blue 0
8 PM Wed 61 51 NW 2 2 2566 3200 0 Blue 0
9 PM Wed 60 50 NNW 1 2 2566 3200 0 Blue 0
10 PM Wed 60 50 NNW 1 2 2566 3200 0 Blue 0
11 PM Wed 59 49 NNW 2 2 2566 3200 0 Blue 0
12 Midnight Thu 59 49 NNW 2 2 2566 3200 0 Blue 0
1 AM Thu 58 48 NNW 2 2 2566 3200 0 Blue 0
2 AM Thu 58 48 NNW 2 3 2566 3200 0 Blue 0
3 AM Thu 56 46 NNW 3 3 2566 3200 0 Blue 0
4 AM Thu 55 45 N 2 3 2566 3200 0 Blue 0
5 AM Thu 54 44 N 2 2 2566 3200 0 Blue 0
6 AM Thu 54 44 N 2 2 2566 3200 0 Blue 0
7 AM Thu 57 47 NNE 2 3 2566 3200 0 Blue 0
8 AM Thu 61 52 NNE 1 1 2566 3200 0 Blue 0
9 AM Thu 63 55 NNE 1 1 2566 3200 0 Blue 0
10 AM Thu 63 57 N 1 1 2566 3200 0 Blue 0
11 AM Thu 63 59 SSW 2 2 2566 3200 0 Blue 0
12 Noon Thu 63 60 SSW 2 2 2566 3200 0 Blue 0
1 PM Thu 63 60 SSW 2 2 2566 3200 0 Blue 0
2 PM Thu 63 59 W 3 4 2566 3200 0 Blue 0
3 PM Thu 63 58 W 3 4 2566 3200 0 Blue 0
4 PM Thu 63 57 W 3 4 2566 3200 0 Blue 0
5 PM Thu 63 55 WNW 4 4 2566 3200 0 Blue 0
6 PM Thu 62 53 WNW 4 4 2566 3200 0 Blue 0
7 PM Thu 60 50 WNW 4 4 2566 3200 0 Blue 0
8 PM Thu 58 48 WNW 4 6 2566 3200 0 Blue 0
9 PM Thu 57 47 WNW 4 6 2566 3200 0 Blue 0
10 PM Thu 56 46 WNW 4 6 2566 3200 0 Blue 0
11 PM Thu 56 46 WNW 5 6 2566 3200 0 Blue 0
12 Midnight Fri 55 45 WNW 5 6 2566 3200 0 Blue 0
1 AM Fri 55 45 WNW 5 6 2566 3200 0 Blue 0
2 AM Fri 54 44 NW 4 6 2566 3200 0 Blue 0
3 AM Fri 53 43 NW 4 6 2566 3200 0 Blue 0
4 AM Fri 52 42 NW 4 6 2566 3200 0 Blue 0
5 AM Fri 52 42 NW 4 5 2566 3200 0 Blue 0
6 AM Fri 53 43 NW 4 5 2566 3200 0 Blue 0
7 AM Fri 55 45 NW 4 5 2566 3200 0 Blue 0
8 AM Fri 57 48 NW 3 4 2566 3200 0 Blue 0
9 AM Fri 58 50 NW 3 4 2566 3200 0 Blue 0
10 AM Fri 59 53 NW 3 4 2566 3200 0 Blue 0
11 AM Fri 60 56 WNW 3 4 2566 3200 0 Blue 0
12 Noon Fri 61 58 WNW 3 4 2566 3200 0 Blue 0
1 PM Fri 61 58 WNW 3 4 2566 3200 0 Blue 0
2 PM Fri 61 58 W 4 6 2566 3200 0 Blue 0
3 PM Fri 62 58 W 4 6 2566 3200 0 Blue 0
4 PM Fri 61 55 W 4 6 2566 3200 0 Blue 0
5 PM Fri 61 53 W 5 6 2566 3200 0 Blue 0
6 PM Fri 60 51 W 5 6 2566 3200 0 Blue 0
7 PM Fri 58 48 W 5 6 2566 3200 0 Blue 0
8 PM Fri 57 47 W 5 6 2566 3200 0 Blue 0
9 PM Fri 56 46 W 5 6 2566 3200 0 Blue 0
10 PM Fri 54 44 W 5 6 2566 3200 0 Blue 0
11 PM Fri 53 43 W 5 8 2566 3200 0 Blue 0
12 Midnight Sat 52 42 W 5 8 2566 3200 0 Blue 0
1 AM Sat 52 42 W 5 8 2566 3200 0 Blue 0
2 AM Sat 51 41 W 6 8 2566 3200 0 Blue 0
3 AM Sat 50 40 W 6 8 2566 3200 0 Blue 0
4 AM Sat 49 39 W 6 8 2566 3200 0 Blue 0
5 AM Sat 49 39 W 5 6 2566 3200 0 Blue 0
6 AM Sat 49 39 W 5 6 2566 3200 0 Blue 0
7 AM Sat 50 40 W 5 6 2566 3200 0 Blue 0
8 AM Sat 51 41 WNW 5 6 2566 3200 0 Blue 0
9 AM Sat 53 45 WNW 5 6 2566 3200 0 Blue 0
10 AM Sat 54 47 WNW 5 6 2566 3200 0 Blue 0
11 AM Sat 55 50 W 3 4 2566 3200 0 Blue 0
12 Noon Sat 55 51 W 3 4 2566 3200 0 Blue 0
1 PM Sat 55 52 W 3 4 2566 3200 0 Blue 0
2 PM Sat 54 50 WSW 2 3 2566 3200 0 Blue 0
3 PM Sat 54 49 WSW 2 3 2566 3200 0 Blue 0
4 PM Sat 54 47 WSW 2 3 2566 3200 0 Blue 0
5 PM Sat 54 46 W 2 2 2566 3200 0 Blue 0
6 PM Sat 54 45 W 2 2 2566 3200 0 Blue 0
7 PM Sat 54 44 W 2 2 2566 3200 0 Blue 0
8 PM Sat 53 43 W 1 1 2566 3200 0 Blue 0
9 PM Sat 53 43 W 1 1 2566 3200 0 Blue 0
10 PM Sat 52 42 W 1 1 2566 3200 0 Blue 0
11 PM Sat 52 42 W 2 2 2566 3200 0 Blue 0
12 Midnight Sun 51 41 W 2 2 2566 3200 0 Blue 0
1 AM Sun 51 41 W 2 2 2566 3200 0 Blue 0
2 AM Sun 50 40 SSW 2 2 2566 3200 0 Blue 0
3 AM Sun 50 40 SSW 2 2 2566 3200 0 Blue 0
4 AM Sun 49 39 SSW 2 2 2566 3200 0 Blue 0
5 AM Sun 49 39 S 3 4 2566 3200 0 Blue 0
6 AM Sun 50 40 S 3 4 2566 3200 0 Blue 0
7 AM Sun 50 40 S 3 4 2566 3200 0 Blue 0
8 AM Sun 52 42 S 1 1 2566 3200 0 Blue 0
9 AM Sun 53 44 S 1 1 2566 3200 0 Blue 0
10 AM Sun 54 46 S 1 1 2566 3200 0 Blue 0
11 AM Sun 55 50 SSW 2 2 2566 3200 0 Blue 0
12 Noon Sun 56 52 SSW 2 2 2566 3200 0 Blue 0
1 PM Sun 56 52 SSW 2 2 2566 3200 0 Blue 0
2 PM Sun 57 53 SW 2 2 2566 3200 0 Blue 0
3 PM Sun 57 52 SW 2 2 2566 3200 0 Blue 0
4 PM Sun 56 50 SW 2 2 2566 3200 0 Blue 0
5 PM Sun 56 48 SW 2 2 2566 3200 0 Blue 0
6 PM Sun 55 46 SW 2 2 2566 3200 0 Blue 0
7 PM Sun 54 44 SW 2 2 2566 3200 0 Blue 0
8 PM Sun 54 44 WSW 1 1 2566 3200 0 Blue 0
9 PM Sun 53 43 WSW 1 1 2566 3200 0 Blue 0
10 PM Sun 52 42 WSW 1 1 2566 3200 0 Blue 0
11 PM Sun 52 42 W 1 1 2566 3200 0 Blue 0
12 Midnight Mon 52 42 W 1 1 2566 3200 0 Blue 0
1 AM Mon 52 42 W 1 1 2566 3200 0 Blue 0
2 AM Mon 51 41 NW 1 1 2566 3200 0 Blue 0
3 AM Mon 50 40 NW 1 1 2566 3200 0 Blue 0
4 AM Mon 50 40 NW 1 1 2566 3200 0 Blue 0
5 AM Mon 50 40 NNW 2 2 2566 3200 0 Blue 0
6 AM Mon 50 40 NNW 2 2 2566 3200 0 Blue 0
7 AM Mon 51 41 NNW 2 2 2566 3200 0 Blue 0
8 AM Mon 53 44 W 1 1 2566 3200 0 Blue 0
9 AM Mon 55 47 W 1 1 2566 3200 0 Blue 0
10 AM Mon 56 49 W 1 1 2566 3200 0 Blue 0
11 AM Mon 57 53 W 1 2 2566 3200 0 Blue 0
12 Noon Mon 58 55 W 1 2 2566 3200 0 Blue 0
1 PM Mon 59 56 W 1 2 2566 3200 0 Blue 0
2 PM Mon 60 57 W 4 5 2566 3200 0 Blue 0
3 PM Mon 60 56 W 4 5 2566 3200 0 Blue 0
4 PM Mon 59 53 W 4 5 2566 3200 0 Blue 0
5 PM Mon 59 51 WNW 2 2 2566 3200 0 Blue 0
6 PM Mon 58 49 WNW 2 2 2566 3200 0 Blue 0
7 PM Mon 58 48 WNW 2 2 2566 3200 0 Blue 0
8 PM Mon 57 47 NW 2 3 2566 3200 0 Blue 0
9 PM Mon 56 46 NW 2 3 2566 3200 0 Blue 0
10 PM Mon 54 44 NW 2 3 2566 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 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 ac_soaring@yahoo.com