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

Station:

KOAK

Date/Time:

22 JUL 2018

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 Sun 69 59 E 3 2713 3200 0 Blue 0
6 AM Sun 69 59 E 3 2713 3200 0 Blue 0
7 AM Sun 69 59 E 3 2713 3200 0 Blue 0
8 AM Sun 70 60 N 2 2713 3200 0 Blue 0
9 AM Sun 74 66 N 2 2718 3200 0 Blue 0
10 AM Sun 75 68 N 2 2756 3200 0 Blue 0
11 AM Sun 76 72 SW 5 2832 3200 0 Blue 0
12 Noon Sun 77 75 SW 5 2897 3200 0 Blue 3
1 PM Sun 78 76 SW 5 3120 3200 0 Blue 4
2 PM Sun 79 77 SW 6 3358 3200 0 Blue 5
3 PM Sun 81 78 SW 6 3608 3200 0 Blue 6
4 PM Sun 81 76 SW 6 3120 3200 0 Blue 4
5 PM Sun 81 74 SW 5 2875 3200 0 Blue 2
6 PM Sun 80 71 SW 5 2813 3200 0 Blue 0
7 PM Sun 79 69 SW 5 2775 3200 0 Blue 0
8 PM Sun 75 65 S 2 2713 3200 0 Blue 0
9 PM Sun 73 63 S 2 2713 3200 0 Blue 0
10 PM Sun 73 63 S 2 2713 3200 0 Blue 0
11 PM Sun 74 64 NE 2 2713 3200 0 Blue 0
12 Midnight Mon 74 64 NE 2 2713 3200 0 Blue 0
1 AM Mon 74 64 NE 2 2713 3200 0 Blue 0
2 AM Mon 74 64 NE 3 2713 3200 0 Blue 0
3 AM Mon 74 64 NE 3 2713 3200 0 Blue 0
4 AM Mon 73 63 NE 3 2713 3200 0 Blue 0
5 AM Mon 72 62 NE 3 2713 3200 0 Blue 0
6 AM Mon 72 62 NE 3 2713 3200 0 Blue 0
7 AM Mon 72 62 NE 3 2713 3200 0 Blue 0
8 AM Mon 74 64 N 2 2713 3200 0 Blue 0
9 AM Mon 79 71 N 2 2813 3200 0 Blue 0
10 AM Mon 80 73 N 2 2853 3200 0 Blue 1
11 AM Mon 82 78 SW 5 3608 3200 0 Blue 6
12 Noon Mon 83 81 SW 5 4640 3601 401 Blue 9
1 PM Mon 84 82 SW 5 5018 3848 648 Blue 10
2 PM Mon 86 84 W 5 5936 4619 1419 Blue 12
3 PM Mon 89 86 W 5 6484 5528 2328 Blue 14
4 PM Mon 88 83 W 5 5577 4255 1055 Blue 11
5 PM Mon 88 81 W 5 4640 3601 401 Blue 9
6 PM Mon 88 79 W 5 3856 3200 0 Blue 7
7 PM Mon 85 75 W 5 2897 3200 0 Blue 3
8 PM Mon 80 70 W 5 2794 3200 0 Blue 0
9 PM Mon 77 67 W 5 2737 3200 0 Blue 0
10 PM Mon 78 68 W 5 2756 3200 0 Blue 0
11 PM Mon 78 68 W 5 2756 3200 0 Blue 0
12 Midnight Tue 78 68 W 5 2756 3200 0 Blue 0
1 AM Tue 78 68 W 5 2756 3200 0 Blue 0
2 AM Tue 78 68 W 5 2756 3200 0 Blue 0
3 AM Tue 78 68 W 5 2756 3200 0 Blue 0
4 AM Tue 77 67 W 5 2737 3200 0 Blue 0
5 AM Tue 75 65 NW 5 2713 3200 0 Blue 0
6 AM Tue 75 65 NW 5 2713 3200 0 Blue 0
7 AM Tue 76 66 NW 5 2718 3200 0 Blue 0
8 AM Tue 77 68 NW 5 2756 3200 0 Blue 0
9 AM Tue 82 74 NW 5 2875 3200 0 Blue 2
10 AM Tue 83 77 NW 5 3358 3200 0 Blue 5
11 AM Tue 85 81 W 8 4640 3601 401 Blue 9
12 Noon Tue 87 85 W 8 6211 4992 1792 Blue 13
1 PM Tue 88 87 W 8 7317 5909 2709 Blue 15
2 PM Tue 89 87 W 8 7317 5909 2709 Blue 15
3 PM Tue 92 89 W 8 8338 6453 3253 Blue 17
4 PM Tue 92 87 W 8 7317 5909 2709 Blue 15
5 PM Tue 92 85 W 7 6211 4992 1792 Blue 13
6 PM Tue 91 82 W 7 5018 3848 648 Blue 10
7 PM Tue 88 78 W 7 3608 3200 0 Blue 6
8 PM Tue 83 73 W 7 2853 3200 0 Blue 1
9 PM Tue 80 70 W 7 2794 3200 0 Blue 0
10 PM Tue 80 70 W 7 2794 3200 0 Blue 0
11 PM Tue 81 71 NW 5 2813 3200 0 Blue 0
12 Midnight Wed 81 71 NW 5 2813 3200 0 Blue 0
1 AM Wed 80 70 NW 5 2794 3200 0 Blue 0
2 AM Wed 81 71 NW 5 2813 3200 0 Blue 0
3 AM Wed 81 71 NW 5 2813 3200 0 Blue 0
4 AM Wed 80 70 NW 5 2794 3200 0 Blue 0
5 AM Wed 78 68 NW 5 2756 3200 0 Blue 0
6 AM Wed 78 68 NW 5 2756 3200 0 Blue 0
7 AM Wed 78 68 NW 5 2756 3200 0 Blue 0
8 AM Wed 80 71 NW 5 2813 3200 0 Blue 0
9 AM Wed 83 75 NW 5 2897 3200 0 Blue 3
10 AM Wed 84 78 NW 5 3608 3200 0 Blue 6
11 AM Wed 85 81 NW 15 4640 3601 401 Blue 9
12 Noon Wed 86 83 NW 15 5577 4255 1055 Blue 11
1 PM Wed 87 85 NW 15 6211 4992 1792 Blue 13
2 PM Wed 89 87 NW 15 7317 5909 2709 Blue 15
3 PM Wed 90 87 NW 15 7317 5909 2709 Blue 15
4 PM Wed 90 85 NW 15 6211 4992 1792 Blue 13
5 PM Wed 90 83 NW 17 5577 4255 1055 Blue 11
6 PM Wed 90 81 NW 17 4640 3601 401 Blue 9
7 PM Wed 87 77 NW 17 3358 3200 0 Blue 5
8 PM Wed 82 72 NW 17 2832 3200 0 Blue 0
9 PM Wed 80 70 NW 17 2794 3200 0 Blue 0
10 PM Wed 80 70 NW 17 2794 3200 0 Blue 0
11 PM Wed 80 70 N 13 2794 3200 0 Blue 0
12 Midnight Thu 81 71 N 13 2813 3200 0 Blue 0
1 AM Thu 80 70 N 13 2794 3200 0 Blue 0
2 AM Thu 80 70 N 13 2794 3200 0 Blue 0
3 AM Thu 80 70 N 13 2794 3200 0 Blue 0
4 AM Thu 79 69 N 13 2775 3200 0 Blue 0
5 AM Thu 78 68 N 9 2756 3200 0 Blue 0
6 AM Thu 78 68 N 9 2756 3200 0 Blue 0
7 AM Thu 78 68 N 9 2756 3200 0 Blue 0
8 AM Thu 80 71 N 9 2813 3200 0 Blue 0
9 AM Thu 83 75 N 9 2897 3200 0 Blue 3
10 AM Thu 84 78 N 9 3608 3200 0 Blue 6
11 AM Thu 85 81 NW 17 4640 3601 401 Blue 9
12 Noon Thu 86 83 NW 17 5577 4255 1055 Blue 11
1 PM Thu 87 85 NW 17 6211 4992 1792 Blue 13
2 PM Thu 88 86 NW 17 6484 5528 2328 Blue 14
3 PM Thu 90 87 NW 17 7317 5909 2709 Blue 15
4 PM Thu 90 85 NW 17 6211 4992 1792 Blue 13
5 PM Thu 90 83 NW 16 5577 4255 1055 Blue 11
6 PM Thu 89 80 NW 16 4272 3354 154 Blue 8
7 PM Thu 86 76 NW 16 3120 3200 0 Blue 4
8 PM Thu 79 69 NW 16 2775 3200 0 Blue 0
9 PM Thu 76 66 NW 16 2718 3200 0 Blue 0
10 PM Thu 76 66 NW 16 2718 3200 0 Blue 0
11 PM Thu 77 67 N 12 2737 3200 0 Blue 0
12 Midnight Fri 77 67 N 12 2737 3200 0 Blue 0
1 AM Fri 76 66 N 12 2718 3200 0 Blue 0
2 AM Fri 77 67 N 12 2737 3200 0 Blue 0
3 AM Fri 76 66 N 12 2718 3200 0 Blue 0
4 AM Fri 75 65 N 12 2713 3200 0 Blue 0
5 AM Fri 73 63 N 9 2713 3200 0 Blue 0
6 AM Fri 73 63 N 9 2713 3200 0 Blue 0
7 AM Fri 74 64 N 9 2713 3200 0 Blue 0
8 AM Fri 75 65 N 9 2713 3200 0 Blue 0
9 AM Fri 79 70 N 9 2794 3200 0 Blue 0
10 AM Fri 80 73 N 9 2853 3200 0 Blue 1
11 AM Fri 81 77 NW 12 3358 3200 0 Blue 5
12 Noon Fri 82 80 NW 12 4272 3354 154 Blue 8
1 PM Fri 83 82 NW 12 5018 3848 648 Blue 10
2 PM Fri 85 83 NW 12 5577 4255 1055 Blue 11
3 PM Fri 87 84 NW 12 5936 4619 1419 Blue 12
4 PM Fri 86 81 NW 12 4640 3601 401 Blue 9
5 PM Fri 87 80 NW 13 4272 3354 154 Blue 8
6 PM Fri 86 77 NW 13 3358 3200 0 Blue 5
7 PM Fri 83 73 NW 13 2853 3200 0 Blue 1
8 PM Fri 77 67 NW 13 2737 3200 0 Blue 0
9 PM Fri 74 64 NW 13 2713 3200 0 Blue 0
10 PM Fri 74 64 NW 13 2713 3200 0 Blue 0
11 PM Fri 74 64 N 9 2713 3200 0 Blue 0
12 Midnight Sat 75 65 N 9 2713 3200 0 Blue 0
1 AM Sat 74 64 N 9 2713 3200 0 Blue 0
2 AM Sat 75 65 N 9 2713 3200 0 Blue 0
3 AM Sat 74 64 N 9 2713 3200 0 Blue 0
4 AM Sat 73 63 N 9 2713 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