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

Station:

KVBG

Date/Time:

20 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 Tue 58 58 W 8 5270 9085 0 Blue 0
6 AM Tue 60 60 W 7 6047 9085 0 Blue 0
7 AM Tue 56 56 W 5 4915 9085 0 Blue 0
8 AM Tue 63 64 W 3 7547 9085 0 Blue 0
9 AM Tue 65 67 SW 5 8627 9085 0 Blue 0
10 AM Tue 68 72 S 6 10382 9308 223 Blue 0
11 AM Tue 70 76 SE 8 14374 11446 2361 Blue 4
12 Noon Tue 73 80 SE 10 17193 14960 5875 Blue 8
1 PM Tue 75 83 SE 14 18967 16991 7906 Blue 11
2 PM Tue 76 83 SE 15 18967 16991 7906 Blue 11
3 PM Tue 77 83 SE 16 18967 16991 7906 Blue 11
4 PM Tue 77 81 SE 16 17809 15675 6590 Blue 9
5 PM Tue 76 78 SE 16 15867 13369 4284 Blue 6
6 PM Tue 74 75 S 14 13539 10325 1240 Blue 3
7 PM Tue 71 71 SW 12 10017 9085 0 Blue 0
8 PM Tue 67 67 SW 9 8627 9085 0 Blue 0
9 PM Tue 65 65 W 8 7911 9085 0 Blue 0
10 PM Tue 64 64 W 8 7547 9085 0 Blue 0
11 PM Tue 63 63 W 8 7178 9085 0 Blue 0
12 Midnight Wed 62 62 W 8 6806 9085 0 Blue 0
1 AM Wed 62 62 W 9 6806 9085 0 Blue 0
2 AM Wed 61 61 W 9 6429 9085 0 Blue 0
3 AM Wed 60 60 W 9 6047 9085 0 Blue 0
4 AM Wed 60 60 W 10 6047 9085 0 Blue 0
5 AM Wed 59 59 NW 9 5661 9085 0 Blue 0
6 AM Wed 58 58 NW 9 5270 9085 0 Blue 0
7 AM Wed 61 61 NW 8 6429 9085 0 Blue 0
8 AM Wed 66 67 NW 8 8627 9085 0 Blue 0
9 AM Wed 69 71 N 8 10017 9085 0 Blue 0
10 AM Wed 71 75 NE 8 13539 10325 1240 Blue 3
11 AM Wed 73 79 E 8 16547 14195 5110 Blue 7
12 Noon Wed 75 82 E 9 18399 16350 7265 Blue 10
1 PM Wed 76 84 E 10 19604 17603 8518 Blue 12
2 PM Wed 78 85 SE 13 20351 18190 9105 Blue 13
3 PM Wed 79 85 SE 14 20351 18190 9105 Blue 13
4 PM Wed 79 83 SE 15 18967 16991 7906 Blue 11
5 PM Wed 78 80 SE 16 17193 14960 5875 Blue 8
6 PM Wed 75 76 SE 15 14374 11446 2361 Blue 4
7 PM Wed 71 71 S 14 10017 9085 0 Blue 0
8 PM Wed 68 68 S 12 8980 9085 0 Blue 0
9 PM Wed 66 66 S 10 8271 9085 0 Blue 0
10 PM Wed 65 65 SW 9 7911 9085 0 Blue 0
11 PM Wed 65 65 W 8 7911 9085 0 Blue 0
12 Midnight Thu 65 65 W 7 7911 9085 0 Blue 0
1 AM Thu 64 64 W 8 7547 9085 0 Blue 0
2 AM Thu 63 63 W 8 7178 9085 0 Blue 0
3 AM Thu 61 61 W 9 6429 9085 0 Blue 0
4 AM Thu 60 60 W 9 6047 9085 0 Blue 0
5 AM Thu 60 60 W 9 6047 9085 0 Blue 0
6 AM Thu 62 62 NW 8 6806 9085 0 Blue 0
7 AM Thu 64 64 NW 7 7547 9085 0 Blue 0
8 AM Thu 68 69 N 6 9329 9085 0 Blue 0
9 AM Thu 70 72 N 6 10382 9308 223 Blue 0
10 AM Thu 72 76 E 7 14374 11446 2361 Blue 4
11 AM Thu 74 79 SE 8 16547 14195 5110 Blue 7
12 Noon Thu 76 82 SE 9 18399 16350 7265 Blue 10
1 PM Thu 77 83 SE 12 18967 16991 7906 Blue 11
2 PM Thu 78 83 SE 13 18967 16991 7906 Blue 11
3 PM Thu 79 83 SE 14 18967 16991 7906 Blue 11
4 PM Thu 79 82 SE 14 18399 16350 7265 Blue 10
5 PM Thu 77 79 SE 14 16547 14195 5110 Blue 7
6 PM Thu 74 74 S 13 12622 9989 904 Blue 2
7 PM Thu 70 70 S 10 9675 9085 0 Blue 0
8 PM Thu 66 66 SW 8 8271 9085 0 Blue 0
9 PM Thu 64 64 SW 8 7547 9085 0 Blue 0
10 PM Thu 62 62 SW 8 6806 9085 0 Blue 0
11 PM Thu 62 62 SW 8 6806 9085 0 Blue 0
12 Midnight Fri 61 61 SW 8 6429 9085 0 Blue 0
1 AM Fri 61 61 SW 7 6429 9085 0 Blue 0
2 AM Fri 60 60 W 7 6047 9085 0 Blue 0
3 AM Fri 59 59 W 7 5661 9085 0 Blue 0
4 AM Fri 58 58 W 7 5270 9085 0 Blue 0
5 AM Fri 58 58 W 7 5270 9085 0 Blue 0
6 AM Fri 60 60 SW 7 6047 9085 0 Blue 0
7 AM Fri 63 63 S 8 7178 9085 0 Blue 0
8 AM Fri 66 66 S 8 8271 9085 0 Blue 0
9 AM Fri 68 70 S 8 9675 9085 0 Blue 0
10 AM Fri 70 74 S 8 12622 9989 904 Blue 2
11 AM Fri 72 77 S 8 15145 12463 3378 Blue 5
12 Noon Fri 74 81 S 10 17809 15675 6590 Blue 9
1 PM Fri 76 83 SE 13 18967 16991 7906 Blue 11
2 PM Fri 77 84 SE 15 19604 17603 8518 Blue 12
3 PM Fri 78 84 SE 16 19604 17603 8518 Blue 12
4 PM Fri 78 82 SE 16 18399 16350 7265 Blue 10
5 PM Fri 76 78 SE 15 15867 13369 4284 Blue 6
6 PM Fri 73 74 S 14 12622 9989 904 Blue 2
7 PM Fri 70 70 S 10 9675 9085 0 Blue 0
8 PM Fri 67 67 S 9 8627 9085 0 Blue 0
9 PM Fri 65 65 S 8 7911 9085 0 Blue 0
10 PM Fri 64 64 S 9 7547 9085 0 Blue 0
11 PM Fri 63 63 S 9 7178 9085 0 Blue 0
12 Midnight Sat 63 63 S 9 7178 9085 0 Blue 0
1 AM Sat 62 62 SW 8 6806 9085 0 Blue 0
2 AM Sat 61 61 SW 8 6429 9085 0 Blue 0
3 AM Sat 60 60 SW 8 6047 9085 0 Blue 0
4 AM Sat 59 59 SW 8 5661 9085 0 Blue 0
5 AM Sat 59 59 SW 8 5661 9085 0 Blue 0
6 AM Sat 61 61 SW 8 6429 9085 0 Blue 0
7 AM Sat 64 64 S 8 7547 9085 0 Blue 0
8 AM Sat 67 67 S 9 8627 9085 0 Blue 0
9 AM Sat 69 71 S 8 10017 9085 0 Blue 0
10 AM Sat 71 75 S 8 13539 10325 1240 Blue 3
11 AM Sat 73 79 S 9 16547 14195 5110 Blue 7
12 Noon Sat 75 82 S 10 18399 16350 7265 Blue 10
1 PM Sat 77 84 S 14 19604 17603 8518 Blue 12
2 PM Sat 78 85 S 15 20351 18190 9105 Blue 13
3 PM Sat 79 85 S 16 20351 18190 9105 Blue 13
4 PM Sat 79 83 S 16 18967 16991 7906 Blue 11
5 PM Sat 77 79 S 15 16547 14195 5110 Blue 7
6 PM Sat 74 74 S 14 12622 9989 904 Blue 2
7 PM Sat 70 70 SW 12 9675 9085 0 Blue 0
8 PM Sat 67 67 SW 9 8627 9085 0 Blue 0
9 PM Sat 65 65 SW 9 7911 9085 0 Blue 0
10 PM Sat 64 64 SW 9 7547 9085 0 Blue 0
11 PM Sat 64 64 SW 9 7547 9085 0 Blue 0
12 Midnight Sun 63 63 SW 8 7178 9085 0 Blue 0
1 AM Sun 62 62 SW 8 6806 9085 0 Blue 0
2 AM Sun 61 61 SW 7 6429 9085 0 Blue 0
3 AM Sun 60 60 SW 7 6047 9085 0 Blue 0
4 AM Sun 59 59 SW 7 5661 9085 0 Blue 0
5 AM Sun 59 59 SW 7 5661 9085 0 Blue 0
6 AM Sun 61 61 SW 7 6429 9085 0 Blue 0
7 AM Sun 64 64 S 7 7547 9085 0 Blue 0
8 AM Sun 66 66 S 7 8271 9085 0 Blue 0
9 AM Sun 69 71 S 7 10017 9085 0 Blue 0
10 AM Sun 71 75 S 7 13539 10325 1240 Blue 3
11 AM Sun 73 79 S 7 16547 14195 5110 Blue 7
12 Noon Sun 74 81 S 9 17809 15675 6590 Blue 9
1 PM Sun 76 83 S 12 18967 16991 7906 Blue 11
2 PM Sun 78 85 SE 14 20351 18190 9105 Blue 13
3 PM Sun 79 85 SE 15 20351 18190 9105 Blue 13
4 PM Sun 79 83 SE 14 18967 16991 7906 Blue 11
5 PM Sun 78 80 SE 14 17193 14960 5875 Blue 8
6 PM Sun 75 75 S 12 13539 10325 1240 Blue 3
7 PM Sun 72 72 SW 10 10382 9308 223 Blue 0
8 PM Sun 69 69 SW 8 9329 9085 0 Blue 0
9 PM Sun 66 66 SW 8 8271 9085 0 Blue 0
10 PM Sun 65 65 SW 8 7911 9085 0 Blue 0
11 PM Sun 64 64 SW 8 7547 9085 0 Blue 0
12 Midnight Mon 64 64 W 8 7547 9085 0 Blue 0
1 AM Mon 63 63 W 8 7178 9085 0 Blue 0
2 AM Mon 62 62 W 8 6806 9085 0 Blue 0
3 AM Mon 62 62 W 8 6806 9085 0 Blue 0
4 AM Mon 61 61 W 8 6429 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