Detailed Predictions for: Horseshoe
Launch Altitude (f): 9085
LZ Altitude (f): 3640
Sounding

Station:

KVBG

Date/Time:

21 AUG 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)
5 AM Wed 61 61 NW 15 5902 9085 0 Blue 0
6 AM Wed 59 59 NW 14 5902 9085 0 Blue 0
7 AM Wed 60 60 N 13 5902 9085 0 Blue 0
8 AM Wed 66 67 N 12 5910 9085 0 Blue 0
9 AM Wed 69 71 N 12 8954 9085 0 Blue 0
10 AM Wed 72 76 NE 12 12145 10198 1113 Blue 3
11 AM Wed 74 80 E 12 14278 12633 3548 Blue 7
12 Noon Wed 76 83 E 13 15656 14174 5089 Blue 9
1 PM Wed 79 87 E 14 17363 15974 6889 Blue 13
2 PM Wed 80 87 E 15 17363 15974 6889 Blue 13
3 PM Wed 81 87 SE 16 17363 15974 6889 Blue 13
4 PM Wed 80 84 SE 17 16096 14640 5555 Blue 10
5 PM Wed 80 82 SE 17 15208 13698 4613 Blue 9
6 PM Wed 78 79 S 15 13796 12057 2972 Blue 6
7 PM Wed 75 75 SW 13 11538 9573 488 Blue 2
8 PM Wed 69 69 SW 10 7524 9085 0 Blue 0
9 PM Wed 67 67 SW 9 5910 9085 0 Blue 0
10 PM Wed 66 66 W 8 5902 9085 0 Blue 0
11 PM Wed 66 66 W 8 5902 9085 0 Blue 0
12 Midnight Thu 65 65 W 9 5902 9085 0 Blue 0
1 AM Thu 64 64 W 12 5902 9085 0 Blue 0
2 AM Thu 64 64 W 14 5902 9085 0 Blue 0
3 AM Thu 63 63 W 14 5902 9085 0 Blue 0
4 AM Thu 63 63 W 14 5902 9085 0 Blue 0
5 AM Thu 62 62 NW 13 5902 9085 0 Blue 0
6 AM Thu 60 60 NW 12 5902 9085 0 Blue 0
7 AM Thu 63 63 NW 9 5902 9085 0 Blue 0
8 AM Thu 68 68 NW 8 6745 9085 0 Blue 0
9 AM Thu 70 72 N 8 9617 9085 0 Blue 0
10 AM Thu 72 75 NE 9 11538 9573 488 Blue 2
11 AM Thu 73 78 E 12 13293 11458 2373 Blue 5
12 Noon Thu 75 81 E 14 14748 13190 4105 Blue 8
1 PM Thu 77 83 E 16 15656 14174 5089 Blue 9
2 PM Thu 78 84 SE 17 16096 14640 5555 Blue 10
3 PM Thu 79 84 SE 18 16096 14640 5555 Blue 10
4 PM Thu 79 82 SE 20 15208 13698 4613 Blue 9
5 PM Thu 77 79 SE 18 13796 12057 2972 Blue 6
6 PM Thu 74 74 SE 16 10904 9085 0 Blue 1
7 PM Thu 71 71 S 13 8954 9085 0 Blue 0
8 PM Thu 67 67 S 10 5910 9085 0 Blue 0
9 PM Thu 65 65 S 9 5902 9085 0 Blue 0
10 PM Thu 64 64 SW 8 5902 9085 0 Blue 0
11 PM Thu 63 63 W 8 5902 9085 0 Blue 0
12 Midnight Fri 63 63 W 8 5902 9085 0 Blue 0
1 AM Fri 63 63 W 8 5902 9085 0 Blue 0
2 AM Fri 62 62 W 8 5902 9085 0 Blue 0
3 AM Fri 61 61 W 8 5902 9085 0 Blue 0
4 AM Fri 60 60 W 8 5902 9085 0 Blue 0
5 AM Fri 60 60 W 8 5902 9085 0 Blue 0
6 AM Fri 61 61 NW 7 5902 9085 0 Blue 0
7 AM Fri 64 64 N 6 5902 9085 0 Blue 0
8 AM Fri 67 67 NE 6 5910 9085 0 Blue 0
9 AM Fri 69 71 NE 7 8954 9085 0 Blue 0
10 AM Fri 71 75 E 10 11538 9573 488 Blue 2
11 AM Fri 73 78 SE 13 13293 11458 2373 Blue 5
12 Noon Fri 75 82 SE 15 15208 13698 4613 Blue 9
1 PM Fri 76 83 SE 17 15656 14174 5089 Blue 9
2 PM Fri 77 84 SE 18 16096 14640 5555 Blue 10
3 PM Fri 78 83 SE 20 15656 14174 5089 Blue 9
4 PM Fri 78 82 SE 21 15208 13698 4613 Blue 9
5 PM Fri 76 78 SE 21 13293 11458 2373 Blue 5
6 PM Fri 74 74 S 18 10904 9085 0 Blue 1
7 PM Fri 71 71 S 16 8954 9085 0 Blue 0
8 PM Fri 68 68 SW 13 6745 9085 0 Blue 0
9 PM Fri 65 65 SW 10 5902 9085 0 Blue 0
10 PM Fri 64 64 SW 8 5902 9085 0 Blue 0
11 PM Fri 63 63 SW 7 5902 9085 0 Blue 0
12 Midnight Sat 63 63 SW 7 5902 9085 0 Blue 0
1 AM Sat 63 63 W 8 5902 9085 0 Blue 0
2 AM Sat 62 62 W 9 5902 9085 0 Blue 0
3 AM Sat 61 61 W 9 5902 9085 0 Blue 0
4 AM Sat 60 60 W 9 5902 9085 0 Blue 0
5 AM Sat 60 60 W 9 5902 9085 0 Blue 0
6 AM Sat 62 62 W 8 5902 9085 0 Blue 0
7 AM Sat 65 65 SW 6 5902 9085 0 Blue 0
8 AM Sat 68 68 SW 6 6745 9085 0 Blue 0
9 AM Sat 70 71 S 8 8954 9085 0 Blue 0
10 AM Sat 72 74 SE 10 10904 9085 0 Blue 1
11 AM Sat 73 77 SE 14 12729 10834 1749 Blue 4
12 Noon Sat 75 78 SE 16 13293 11458 2373 Blue 5
1 PM Sat 77 79 SE 17 13796 12057 2972 Blue 6
2 PM Sat 79 79 SE 18 13796 12057 2972 Blue 6
3 PM Sat 80 81 SE 20 14748 13190 4105 Blue 8
4 PM Sat 80 81 SE 21 14748 13190 4105 Blue 8
5 PM Sat 79 80 SE 21 14278 12633 3548 Blue 7
6 PM Sat 75 75 S 18 11538 9573 488 Blue 2
7 PM Sat 71 71 SW 16 8954 9085 0 Blue 0
8 PM Sat 68 68 W 13 6745 9085 0 Blue 0
9 PM Sat 66 66 W 10 5902 9085 0 Blue 0
10 PM Sat 65 65 W 9 5902 9085 0 Blue 0
11 PM Sat 65 65 W 8 5902 9085 0 Blue 0
12 Midnight Sun 64 64 W 8 5902 9085 0 Blue 0
1 AM Sun 63 63 W 8 5902 9085 0 Blue 0
2 AM Sun 63 63 W 9 5902 9085 0 Blue 0
3 AM Sun 62 62 W 9 5902 9085 0 Blue 0
4 AM Sun 61 61 W 9 5902 9085 0 Blue 0
5 AM Sun 62 62 W 9 5902 9085 0 Blue 0
6 AM Sun 63 63 W 7 5902 9085 0 Blue 0
7 AM Sun 66 66 NW 6 5902 9085 0 Blue 0
8 AM Sun 69 69 NW 5 7524 9085 0 Blue 0
9 AM Sun 71 73 N 6 10253 9085 0 Blue 0
10 AM Sun 73 77 NE 9 12729 10834 1749 Blue 4
11 AM Sun 74 80 E 12 14278 12633 3548 Blue 7
12 Noon Sun 76 83 E 14 15656 14174 5089 Blue 9
1 PM Sun 78 85 SE 16 16526 15094 6009 Blue 11
2 PM Sun 80 86 SE 17 16948 15539 6454 Blue 12
3 PM Sun 81 86 SE 17 16948 15539 6454 Blue 12
4 PM Sun 81 84 SE 17 16096 14640 5555 Blue 10
5 PM Sun 80 81 SE 16 14748 13190 4105 Blue 8
6 PM Sun 77 77 S 15 12729 10834 1749 Blue 4
7 PM Sun 74 74 SW 13 10904 9085 0 Blue 1
8 PM Sun 70 70 W 12 8258 9085 0 Blue 0
9 PM Sun 68 68 W 10 6745 9085 0 Blue 0
10 PM Sun 67 67 W 9 5910 9085 0 Blue 0
11 PM Sun 66 66 W 9 5902 9085 0 Blue 0
12 Midnight Mon 66 66 W 9 5902 9085 0 Blue 0
1 AM Mon 66 66 W 9 5902 9085 0 Blue 0
2 AM Mon 65 65 W 9 5902 9085 0 Blue 0
3 AM Mon 64 64 W 10 5902 9085 0 Blue 0
4 AM Mon 63 63 W 12 5902 9085 0 Blue 0
5 AM Mon 63 63 W 12 5902 9085 0 Blue 0
6 AM Mon 65 65 NW 10 5902 9085 0 Blue 0
7 AM Mon 67 67 NW 8 5910 9085 0 Blue 0
8 AM Mon 70 70 N 7 8258 9085 0 Blue 0
9 AM Mon 73 73 N 7 10253 9085 0 Blue 0
10 AM Mon 75 76 E 8 12145 10198 1113 Blue 3
11 AM Mon 76 77 E 10 12729 10834 1749 Blue 4
12 Noon Mon 78 80 E 13 14278 12633 3548 Blue 7
1 PM Mon 79 81 SE 15 14748 13190 4105 Blue 8
2 PM Mon 80 82 SE 16 15208 13698 4613 Blue 9
3 PM Mon 81 83 SE 17 15656 14174 5089 Blue 9
4 PM Mon 81 82 SE 17 15208 13698 4613 Blue 9
5 PM Mon 79 80 SE 16 14278 12633 3548 Blue 7
6 PM Mon 77 77 S 15 12729 10834 1749 Blue 4
7 PM Mon 74 74 S 13 10904 9085 0 Blue 1
8 PM Mon 71 71 SW 12 8954 9085 0 Blue 0
9 PM Mon 68 68 SW 10 6745 9085 0 Blue 0
10 PM Mon 67 67 W 9 5910 9085 0 Blue 0
11 PM Mon 66 66 W 9 5902 9085 0 Blue 0
12 Midnight Tue 66 66 W 9 5902 9085 0 Blue 0
1 AM Tue 66 66 W 10 5902 9085 0 Blue 0
2 AM Tue 65 65 W 12 5902 9085 0 Blue 0
3 AM Tue 64 64 W 13 5902 9085 0 Blue 0
4 AM Tue 63 63 NW 13 5902 9085 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