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

Station:

KTUS

Date/Time:

18 SEP 2019

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 Wed 79 79 E 1 2946 2731 131 Blue 5
7 AM Wed 78 78 E 2 2875 2659 59 Blue 4
8 AM Wed 79 80 SE 3 3042 2802 202 Blue 6
9 AM Wed 81 83 SE 3 3310 3037 437 Blue 9
10 AM Wed 84 88 SE 5 4648 3396 796 Blue 14
11 AM Wed 87 93 S 5 9544 5391 2791 Blue 19
12 Noon Wed 90 96 S 6 11707 9418 6818 White 22
1 PM Wed 93 99 S 6 12320 12320 9720 White 25
2 PM Wed 94 99 SW 7 12320 12320 9720 White 25
3 PM Wed 96 100 SW 7 12523 12523 9923 White 26
4 PM Wed 96 98 SW 8 12116 12116 9516 White 24
5 PM Wed 96 97 W 9 11911 10534 7934 White 23
6 PM Wed 95 95 W 10 11502 8794 6194 White 21
7 PM Wed 94 94 W 10 11297 7391 4791 White 20
8 PM Wed 91 91 W 9 7654 4616 2016 Blue 17
9 PM Wed 89 89 W 9 5037 3711 1111 Blue 15
10 PM Wed 88 88 W 10 4648 3396 796 Blue 14
11 PM Wed 86 86 SW 10 3732 3309 709 Blue 12
12 Midnight Thu 86 86 SW 12 3732 3309 709 Blue 12
1 AM Thu 84 84 SW 10 3354 3218 618 Blue 10
2 AM Thu 83 83 SW 8 3310 3037 437 Blue 9
3 AM Thu 81 81 SW 7 3222 2873 273 Blue 7
4 AM Thu 79 79 SW 6 2946 2731 131 Blue 5
5 AM Thu 78 78 S 5 2875 2659 59 Blue 4
6 AM Thu 77 77 S 5 2803 2600 0 Blue 3
7 AM Thu 77 77 S 6 2803 2600 0 Blue 3
8 AM Thu 77 78 SE 7 2875 2659 59 Blue 4
9 AM Thu 80 82 SE 8 3266 2945 345 Blue 8
10 AM Thu 83 87 SE 8 4195 3353 753 Blue 13
11 AM Thu 85 91 S 9 7654 4616 2016 Blue 17
12 Noon Thu 88 95 S 10 11502 8794 6194 White 21
1 PM Thu 91 98 S 13 12116 12116 9516 White 24
2 PM Thu 93 99 SW 15 12320 12320 9720 White 25
3 PM Thu 94 98 SW 17 12116 12116 9516 White 24
4 PM Thu 95 97 SW 18 11911 10534 7934 White 23
5 PM Thu 94 95 SW 18 11502 8794 6194 White 21
6 PM Thu 93 93 SW 17 9544 5391 2791 Blue 19
7 PM Thu 91 91 SW 16 7654 4616 2016 Blue 17
8 PM Thu 88 88 SW 15 4648 3396 796 Blue 14
9 PM Thu 86 86 W 13 3732 3309 709 Blue 12
10 PM Thu 84 84 W 13 3354 3218 618 Blue 10
11 PM Thu 83 83 SW 12 3310 3037 437 Blue 9
12 Midnight Fri 81 81 SW 12 3222 2873 273 Blue 7
1 AM Fri 79 79 SW 10 2946 2731 131 Blue 5
2 AM Fri 78 78 SW 9 2875 2659 59 Blue 4
3 AM Fri 76 76 SW 8 2732 2600 0 Blue 2
4 AM Fri 75 75 SW 6 2660 2600 0 Blue 1
5 AM Fri 74 74 S 5 0 2600 0 Blue 0
6 AM Fri 73 73 S 3 0 2600 0 Blue 0
7 AM Fri 73 73 S 2 0 2600 0 Blue 0
8 AM Fri 73 74 S 2 0 2600 0 Blue 0
9 AM Fri 75 77 S 2 2803 2600 0 Blue 3
10 AM Fri 78 82 S 3 3266 2945 345 Blue 8
11 AM Fri 81 87 S 5 4195 3353 753 Blue 13
12 Noon Fri 84 91 S 5 7654 4616 2016 Blue 17
1 PM Fri 87 94 S 6 11297 7391 4791 White 20
2 PM Fri 89 95 S 6 11502 8794 6194 White 21
3 PM Fri 90 94 SW 7 11297 7391 4791 White 20
4 PM Fri 91 93 SW 7 9544 5391 2791 Blue 19
5 PM Fri 91 92 W 7 8983 5017 2417 Blue 18
6 PM Fri 90 90 W 7 5659 4168 1568 Blue 16
7 PM Fri 88 88 W 7 4648 3396 796 Blue 14
8 PM Fri 85 85 W 6 3398 3265 665 Blue 11
9 PM Fri 83 83 W 6 3310 3037 437 Blue 9
10 PM Fri 82 82 W 5 3266 2945 345 Blue 8
11 PM Fri 81 81 W 3 3222 2873 273 Blue 7
12 Midnight Sat 80 80 W 3 3042 2802 202 Blue 6
1 AM Sat 79 79 W 3 2946 2731 131 Blue 5
2 AM Sat 77 77 SW 2 2803 2600 0 Blue 3
3 AM Sat 75 75 SW 2 2660 2600 0 Blue 1
4 AM Sat 74 74 S 2 0 2600 0 Blue 0
5 AM Sat 73 73 S 2 0 2600 0 Blue 0
6 AM Sat 72 72 S 2 0 2600 0 Blue 0
7 AM Sat 72 72 S 2 0 2600 0 Blue 0
8 AM Sat 73 74 S 3 0 2600 0 Blue 0
9 AM Sat 75 77 S 3 2803 2600 0 Blue 3
10 AM Sat 78 82 S 3 3266 2945 345 Blue 8
11 AM Sat 82 87 S 3 4195 3353 753 Blue 13
12 Noon Sat 85 91 SE 5 7654 4616 2016 Blue 17
1 PM Sat 87 93 S 5 9544 5391 2791 Blue 19
2 PM Sat 89 94 S 6 11297 7391 4791 White 20
3 PM Sat 90 94 SW 6 11297 7391 4791 White 20
4 PM Sat 91 93 SW 6 9544 5391 2791 Blue 19
5 PM Sat 91 92 W 6 8983 5017 2417 Blue 18
6 PM Sat 90 90 W 6 5659 4168 1568 Blue 16
7 PM Sat 88 88 W 6 4648 3396 796 Blue 14
8 PM Sat 85 85 W 6 3398 3265 665 Blue 11
9 PM Sat 83 83 W 5 3310 3037 437 Blue 9
10 PM Sat 81 81 W 3 3222 2873 273 Blue 7
11 PM Sat 80 80 W 3 3042 2802 202 Blue 6
12 Midnight Sun 79 79 W 2 2946 2731 131 Blue 5
1 AM Sun 78 78 W 1 2875 2659 59 Blue 4
2 AM Sun 77 77 W 1 2803 2600 0 Blue 3
3 AM Sun 76 76 SW 1 2732 2600 0 Blue 2
4 AM Sun 75 75 SW 1 2660 2600 0 Blue 1
5 AM Sun 74 74 S 0 0 2600 0 Blue 0
6 AM Sun 73 73 S 0 0 2600 0 Blue 0
7 AM Sun 73 73 S 0 0 2600 0 Blue 0
8 AM Sun 74 74 S 0 0 2600 0 Blue 0
9 AM Sun 76 78 S 1 2875 2659 59 Blue 4
10 AM Sun 79 83 SE 1 3310 3037 437 Blue 9
11 AM Sun 82 87 SE 1 4195 3353 753 Blue 13
12 Noon Sun 85 91 SE 2 7654 4616 2016 Blue 17
1 PM Sun 88 94 SE 2 11297 7391 4791 White 20
2 PM Sun 90 95 S 3 11502 8794 6194 White 21
3 PM Sun 91 94 S 5 11297 7391 4791 White 20
4 PM Sun 92 94 S 5 11297 7391 4791 White 20
5 PM Sun 91 91 S 6 7654 4616 2016 Blue 17
6 PM Sun 90 90 SW 6 5659 4168 1568 Blue 16
7 PM Sun 88 88 SW 7 4648 3396 796 Blue 14
8 PM Sun 85 85 S 8 3398 3265 665 Blue 11
9 PM Sun 83 83 S 9 3310 3037 437 Blue 9
10 PM Sun 81 81 S 9 3222 2873 273 Blue 7
11 PM Sun 81 81 S 10 3222 2873 273 Blue 7
12 Midnight Mon 80 80 S 10 3042 2802 202 Blue 6
1 AM Mon 79 79 S 10 2946 2731 131 Blue 5
2 AM Mon 79 79 S 10 2946 2731 131 Blue 5
3 AM Mon 78 78 S 9 2875 2659 59 Blue 4
4 AM Mon 77 77 SE 9 2803 2600 0 Blue 3
5 AM Mon 76 76 SE 9 2732 2600 0 Blue 2
6 AM Mon 75 75 SE 9 2660 2600 0 Blue 1
7 AM Mon 75 75 SE 10 2660 2600 0 Blue 1
8 AM Mon 75 75 SE 12 2660 2600 0 Blue 1
9 AM Mon 77 78 SE 13 2875 2659 59 Blue 4
10 AM Mon 79 81 S 14 3222 2873 273 Blue 7
11 AM Mon 81 84 S 15 3354 3218 618 Blue 10
12 Noon Mon 83 87 S 16 4195 3353 753 Blue 13
1 PM Mon 85 88 S 16 4648 3396 796 Blue 14
2 PM Mon 87 90 S 17 5659 4168 1568 Blue 16
3 PM Mon 88 90 S 18 5659 4168 1568 Blue 16
4 PM Mon 88 89 S 18 5037 3711 1111 Blue 15
5 PM Mon 88 88 S 20 4648 3396 796 Blue 14
6 PM Mon 87 87 SW 20 4195 3353 753 Blue 13
7 PM Mon 85 85 SW 18 3398 3265 665 Blue 11
8 PM Mon 83 83 S 18 3310 3037 437 Blue 9
9 PM Mon 81 81 S 17 3222 2873 273 Blue 7
10 PM Mon 80 80 S 16 3042 2802 202 Blue 6
11 PM Mon 79 79 S 15 2946 2731 131 Blue 5
12 Midnight Tue 79 79 S 14 2946 2731 131 Blue 5
1 AM Tue 78 78 S 13 2875 2659 59 Blue 4
2 AM Tue 77 77 S 12 2803 2600 0 Blue 3
3 AM Tue 77 77 SE 10 2803 2600 0 Blue 3
4 AM Tue 76 76 SE 10 2732 2600 0 Blue 2
5 AM Tue 75 75 SE 9 2660 2600 0 Blue 1

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