Detailed Predictions for: South Mountain
Launch Altitude (f): 2600
LZ Altitude (f): 1400
Sounding

Station:

KTUS

Date/Time:

27 MAY 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)
6 AM Sun 69 69 SW 2 3070 2696 96 Blue 4
7 AM Sun 69 70 SW 2 3180 2849 249 Blue 5
8 AM Sun 70 72 S 2 3400 3068 468 Blue 7
9 AM Sun 73 77 S 3 5079 3630 1030 Blue 12
10 AM Sun 75 81 S 5 6633 5241 2641 Blue 16
11 AM Sun 78 85 S 5 7790 6844 4244 Blue 20
12 Noon Sun 82 90 S 6 9338 8379 5779 Blue 25
1 PM Sun 84 92 S 6 9800 8975 6375 Blue 27
2 PM Sun 86 93 SW 6 9999 9270 6670 Blue 28
3 PM Sun 88 93 SW 7 9999 9270 6670 Blue 28
4 PM Sun 88 91 SW 8 9601 8678 6078 Blue 26
5 PM Sun 88 90 W 8 9338 8379 5779 Blue 25
6 PM Sun 88 88 W 9 8741 7731 5131 Blue 23
7 PM Sun 87 87 W 10 8439 7397 4797 Blue 22
8 PM Sun 85 85 W 10 7790 6844 4244 Blue 20
9 PM Sun 83 83 W 10 7126 6226 3626 Blue 18
10 PM Sun 81 81 W 9 6633 5241 2641 Blue 16
11 PM Sun 81 81 W 8 6633 5241 2641 Blue 16
12 Midnight Mon 80 80 W 7 6293 5063 2463 Blue 15
1 AM Mon 80 80 W 7 6293 5063 2463 Blue 15
2 AM Mon 78 78 W 7 5258 4444 1844 Blue 13
3 AM Mon 77 77 W 7 5079 3630 1030 Blue 12
4 AM Mon 75 75 W 5 4500 3396 796 Blue 10
5 AM Mon 75 75 NW 2 4500 3396 796 Blue 10
6 AM Mon 72 72 NW 0 3400 3068 468 Blue 7
7 AM Mon 73 74 N 1 3668 3286 686 Blue 9
8 AM Mon 76 78 E 2 5258 4444 1844 Blue 13
9 AM Mon 78 82 E 3 6880 5695 3095 Blue 17
10 AM Mon 81 87 SE 3 8439 7397 4797 Blue 22
11 AM Mon 84 92 S 3 9800 8975 6375 Blue 27
12 Noon Mon 88 97 SW 3 10849 10146 7546 Blue 32
1 PM Mon 91 100 SW 5 12579 10779 8179 Blue 35
2 PM Mon 93 100 W 7 12579 10779 8179 Blue 35
3 PM Mon 94 100 W 8 12579 10779 8179 Blue 35
4 PM Mon 95 99 W 8 12025 10568 7968 Blue 34
5 PM Mon 95 97 W 9 10849 10146 7546 Blue 32
6 PM Mon 94 94 W 9 10199 9553 6953 Blue 29
7 PM Mon 92 92 W 9 9800 8975 6375 Blue 27
8 PM Mon 90 90 W 10 9338 8379 5779 Blue 25
9 PM Mon 88 88 W 10 8741 7731 5131 Blue 23
10 PM Mon 86 86 W 10 8123 7088 4488 Blue 21
11 PM Mon 85 85 W 10 7790 6844 4244 Blue 20
12 Midnight Tue 84 84 W 10 7453 6599 3999 Blue 19
1 AM Tue 83 83 W 9 7126 6226 3626 Blue 18
2 AM Tue 81 81 W 8 6633 5241 2641 Blue 16
3 AM Tue 80 80 W 7 6293 5063 2463 Blue 15
4 AM Tue 79 79 NW 6 5755 4815 2215 Blue 14
5 AM Tue 77 77 N 3 5079 3630 1030 Blue 12
6 AM Tue 77 77 N 2 5079 3630 1030 Blue 12
7 AM Tue 78 78 NE 2 5258 4444 1844 Blue 13
8 AM Tue 80 82 SE 3 6880 5695 3095 Blue 17
9 AM Tue 82 86 S 5 8123 7088 4488 Blue 21
10 AM Tue 86 91 S 5 9601 8678 6078 Blue 26
11 AM Tue 89 96 SW 3 10626 9949 7349 Blue 31
12 Noon Tue 93 100 SW 3 12579 10779 8179 Blue 35
1 PM Tue 95 102 SW 6 13631 11845 9245 Blue 37
2 PM Tue 98 104 SW 7 14619 12925 10325 Blue 39
3 PM Tue 99 104 W 8 14619 12925 10325 Blue 39
4 PM Tue 100 103 W 9 14132 12395 9795 Blue 38
5 PM Tue 100 101 W 9 13114 11274 8674 Blue 36
6 PM Tue 99 99 W 9 12025 10568 7968 Blue 34
7 PM Tue 97 97 W 9 10849 10146 7546 Blue 32
8 PM Tue 95 95 W 9 10413 9751 7151 Blue 30
9 PM Tue 92 92 W 10 9800 8975 6375 Blue 27
10 PM Tue 90 90 W 10 9338 8379 5779 Blue 25
11 PM Tue 89 89 W 10 9041 8061 5461 Blue 24
12 Midnight Wed 87 87 W 10 8439 7397 4797 Blue 22
1 AM Wed 85 85 W 10 7790 6844 4244 Blue 20
2 AM Wed 84 84 SW 9 7453 6599 3999 Blue 19
3 AM Wed 81 81 SW 8 6633 5241 2641 Blue 16
4 AM Wed 79 79 SW 7 5755 4815 2215 Blue 14
5 AM Wed 77 77 S 7 5079 3630 1030 Blue 12
6 AM Wed 76 76 S 7 4855 3505 905 Blue 11
7 AM Wed 77 77 S 6 5079 3630 1030 Blue 12
8 AM Wed 79 81 S 6 6633 5241 2641 Blue 16
9 AM Wed 82 86 S 7 8123 7088 4488 Blue 21
10 AM Wed 86 92 S 7 9800 8975 6375 Blue 27
11 AM Wed 89 97 S 7 10849 10146 7546 Blue 32
12 Noon Wed 92 101 S 8 13114 11274 8674 Blue 36
1 PM Wed 94 103 S 8 14132 12395 9795 Blue 38
2 PM Wed 96 104 S 9 14619 12925 10325 Blue 39
3 PM Wed 98 104 S 10 14619 12925 10325 Blue 39
4 PM Wed 99 103 SW 12 14132 12395 9795 Blue 38
5 PM Wed 99 101 SW 13 13114 11274 8674 Blue 36
6 PM Wed 98 98 SW 13 11450 10356 7756 Blue 33
7 PM Wed 96 96 SW 13 10626 9949 7349 Blue 31
8 PM Wed 93 93 SW 13 9999 9270 6670 Blue 28
9 PM Wed 90 90 SW 12 9338 8379 5779 Blue 25
10 PM Wed 88 88 SW 12 8741 7731 5131 Blue 23
11 PM Wed 86 86 SW 10 8123 7088 4488 Blue 21
12 Midnight Thu 85 85 SW 10 7790 6844 4244 Blue 20
1 AM Thu 83 83 SW 9 7126 6226 3626 Blue 18
2 AM Thu 81 81 S 9 6633 5241 2641 Blue 16
3 AM Thu 79 79 S 9 5755 4815 2215 Blue 14
4 AM Thu 77 77 S 9 5079 3630 1030 Blue 12
5 AM Thu 75 75 SE 8 4500 3396 796 Blue 10
6 AM Thu 75 75 SE 8 4500 3396 796 Blue 10
7 AM Thu 76 76 SE 9 4855 3505 905 Blue 11
8 AM Thu 78 80 SE 9 6293 5063 2463 Blue 15
9 AM Thu 81 85 S 9 7790 6844 4244 Blue 20
10 AM Thu 84 90 S 10 9338 8379 5779 Blue 25
11 AM Thu 87 94 S 10 10199 9553 6953 Blue 29
12 Noon Thu 90 98 S 12 11450 10356 7756 Blue 33
1 PM Thu 93 100 S 12 12579 10779 8179 Blue 35
2 PM Thu 95 101 S 13 13114 11274 8674 Blue 36
3 PM Thu 97 102 S 14 13631 11845 9245 Blue 37
4 PM Thu 98 101 SW 15 13114 11274 8674 Blue 36
5 PM Thu 98 99 SW 15 12025 10568 7968 Blue 34
6 PM Thu 97 97 SW 15 10849 10146 7546 Blue 32
7 PM Thu 95 95 SW 15 10413 9751 7151 Blue 30
8 PM Thu 92 92 SW 14 9800 8975 6375 Blue 27
9 PM Thu 89 89 SW 14 9041 8061 5461 Blue 24
10 PM Thu 86 86 SW 13 8123 7088 4488 Blue 21
11 PM Thu 84 84 SW 12 7453 6599 3999 Blue 19
12 Midnight Fri 82 82 SW 10 6880 5695 3095 Blue 17
1 AM Fri 81 81 SW 10 6633 5241 2641 Blue 16
2 AM Fri 79 79 S 9 5755 4815 2215 Blue 14
3 AM Fri 77 77 S 9 5079 3630 1030 Blue 12
4 AM Fri 75 75 S 9 4500 3396 796 Blue 10
5 AM Fri 73 73 S 8 3509 3177 577 Blue 8
6 AM Fri 72 72 SE 8 3400 3068 468 Blue 7
7 AM Fri 73 73 SE 8 3509 3177 577 Blue 8
8 AM Fri 76 78 S 8 5258 4444 1844 Blue 13
9 AM Fri 79 83 S 7 7126 6226 3626 Blue 18
10 AM Fri 82 88 S 7 8741 7731 5131 Blue 23
11 AM Fri 85 93 S 7 9999 9270 6670 Blue 28
12 Noon Fri 87 96 S 7 10626 9949 7349 Blue 31
1 PM Fri 90 99 SW 8 12025 10568 7968 Blue 34
2 PM Fri 92 100 SW 8 12579 10779 8179 Blue 35
3 PM Fri 93 99 SW 9 12025 10568 7968 Blue 34
4 PM Fri 94 98 W 9 11450 10356 7756 Blue 33
5 PM Fri 95 97 W 10 10849 10146 7546 Blue 32
6 PM Fri 94 94 W 10 10199 9553 6953 Blue 29
7 PM Fri 92 92 W 10 9800 8975 6375 Blue 27
8 PM Fri 89 89 W 9 9041 8061 5461 Blue 24
9 PM Fri 86 86 W 9 8123 7088 4488 Blue 21
10 PM Fri 84 84 W 9 7453 6599 3999 Blue 19
11 PM Fri 83 83 W 8 7126 6226 3626 Blue 18
12 Midnight Sat 82 82 NW 8 6880 5695 3095 Blue 17
1 AM Sat 81 81 NW 7 6633 5241 2641 Blue 16
2 AM Sat 79 79 NW 7 5755 4815 2215 Blue 14
3 AM Sat 78 78 N 6 5258 4444 1844 Blue 13
4 AM Sat 76 76 N 6 4855 3505 905 Blue 11
5 AM Sat 74 74 N 5 3668 3286 686 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