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

Station:

 KVBG

Date/Time:

 20 MAR 2010

Temp/Wind data from:

NOAA Digital Forecast

Time
(Local)		 High
Temp
Puddle
Temp
Wind
 (mph)		 Thermal
Ceiling
(ft)		 Soaring
Ceiling
(ft)		 Above
Launch
(ft)		 Thermal
Type		 Thermal
Index
(F)
5 AM Sat 26 26 NW 8 5410 9085 0 Blue 0
6 AM Sat 26 26 NW 8 5410 9085 0 Blue 0
7 AM Sat 26 26 NW 8 5410 9085 0 Blue 0
8 AM Sat 31 31 W 6 5410 9085 0 Blue 0
9 AM Sat 40 41 W 6 5410 9085 0 Blue 0
10 AM Sat 48 51 W 6 6773 9085 0 Blue 0
11 AM Sat 52 56 S 2 10545 9085 0 Blue 2
12 Noon Sat 54 59 S 2 13156 10467 1382 Blue 5
1 PM Sat 56 61 S 2 15688 11899 2814 Blue 7
2 PM Sat 57 62 S 6 16644 12854 3769 Blue 8
3 PM Sat 57 61 S 6 15688 11899 2814 Blue 7
4 PM Sat 56 58 S 6 12001 9085 0 Blue 4
5 PM Sat 53 54 SW 8 7491 9085 0 Blue 0
6 PM Sat 48 48 SW 8 6048 9085 0 Blue 0
7 PM Sat 42 42 SW 8 5410 9085 0 Blue 0
8 PM Sat 39 39 SW 6 5410 9085 0 Blue 0
9 PM Sat 34 34 SW 6 5410 9085 0 Blue 0
10 PM Sat 33 33 SW 6 5410 9085 0 Blue 0
11 PM Sat 31 31 W 8 5410 9085 0 Blue 0
12 Midnight Sun 30 30 W 8 5410 9085 0 Blue 0
1 AM Sun 29 29 W 8 5410 9085 0 Blue 0
2 AM Sun 29 29 W 8 5410 9085 0 Blue 0
3 AM Sun 28 28 W 8 5410 9085 0 Blue 0
4 AM Sun 27 27 W 8 5410 9085 0 Blue 0
5 AM Sun 26 26 W 7 5410 9085 0 Blue 0
6 AM Sun 26 26 W 7 5410 9085 0 Blue 0
7 AM Sun 26 26 W 7 5410 9085 0 Blue 0
8 AM Sun 31 31 W 6 5410 9085 0 Blue 0
9 AM Sun 39 40 W 6 5410 9085 0 Blue 0
10 AM Sun 46 49 W 6 6291 9085 0 Blue 0
11 AM Sun 50 54 S 5 7491 9085 0 Blue 0
12 Noon Sun 53 58 S 5 12001 9085 0 Blue 4
1 PM Sun 54 59 S 5 13156 10467 1382 Blue 5
2 PM Sun 55 60 S 10 14558 11205 2120 Blue 6
3 PM Sun 56 60 S 10 14558 11205 2120 Blue 6
4 PM Sun 54 56 S 10 10545 9085 0 Blue 2
5 PM Sun 51 52 SW 10 7013 9085 0 Blue 0
6 PM Sun 46 46 SW 10 5560 9085 0 Blue 0
7 PM Sun 41 41 SW 10 5410 9085 0 Blue 0
8 PM Sun 38 38 SW 10 5410 9085 0 Blue 0
9 PM Sun 33 33 SW 10 5410 9085 0 Blue 0
10 PM Sun 31 31 SW 10 5410 9085 0 Blue 0
11 PM Sun 30 30 W 12 5410 9085 0 Blue 0
12 Midnight Mon 29 29 W 12 5410 9085 0 Blue 0
1 AM Mon 28 28 W 12 5410 9085 0 Blue 0
2 AM Mon 27 27 W 12 5410 9085 0 Blue 0
3 AM Mon 26 26 W 12 5410 9085 0 Blue 0
4 AM Mon 26 26 W 12 5410 9085 0 Blue 0
5 AM Mon 25 25 W 12 5410 9085 0 Blue 0
6 AM Mon 24 24 W 12 5410 9085 0 Blue 0
7 AM Mon 24 24 W 12 5410 9085 0 Blue 0
8 AM Mon 30 30 W 12 5410 9085 0 Blue 0
9 AM Mon 38 39 W 12 5410 9085 0 Blue 0
10 AM Mon 46 48 W 12 6048 9085 0 Blue 0
11 AM Mon 50 54 E 1 7491 9085 0 Blue 0
12 Noon Mon 52 56 E 1 10545 9085 0 Blue 2
1 PM Mon 54 59 E 1 13156 10467 1382 Blue 5
2 PM Mon 55 59 E 1 13156 10467 1382 Blue 5
3 PM Mon 55 58 E 1 12001 9085 0 Blue 4
4 PM Mon 54 56 E 1 10545 9085 0 Blue 2
5 PM Mon 51 52 NW 7 7013 9085 0 Blue 0
6 PM Mon 46 46 NW 7 5560 9085 0 Blue 0
7 PM Mon 41 41 NW 7 5410 9085 0 Blue 0
8 PM Mon 37 37 NW 7 5410 9085 0 Blue 0
9 PM Mon 33 33 NW 7 5410 9085 0 Blue 0
10 PM Mon 31 31 NW 7 5410 9085 0 Blue 0
11 PM Mon 30 30 N 8 5410 9085 0 Blue 0
12 Midnight Tue 29 29 N 8 5410 9085 0 Blue 0
1 AM Tue 28 28 N 8 5410 9085 0 Blue 0
2 AM Tue 27 27 N 8 5410 9085 0 Blue 0
3 AM Tue 26 26 N 8 5410 9085 0 Blue 0
4 AM Tue 26 26 N 8 5410 9085 0 Blue 0
5 AM Tue 25 25 N 10 5410 9085 0 Blue 0
6 AM Tue 24 24 N 10 5410 9085 0 Blue 0
7 AM Tue 24 24 N 10 5410 9085 0 Blue 0
8 AM Tue 29 29 N 10 5410 9085 0 Blue 0
9 AM Tue 36 37 N 10 5410 9085 0 Blue 0
10 AM Tue 42 44 N 10 5410 9085 0 Blue 0
11 AM Tue 46 49 N 16 6291 9085 0 Blue 0
12 Noon Tue 48 51 N 16 6773 9085 0 Blue 0
1 PM Tue 49 52 N 16 7013 9085 0 Blue 0
2 PM Tue 50 53 N 16 7252 9085 0 Blue 0
3 PM Tue 50 52 N 16 7013 9085 0 Blue 0
4 PM Tue 49 50 N 16 6532 9085 0 Blue 0
5 PM Tue 47 47 N 11 5805 9085 0 Blue 0
6 PM Tue 42 42 N 11 5410 9085 0 Blue 0
7 PM Tue 37 37 N 11 5410 9085 0 Blue 0
8 PM Tue 34 34 N 11 5410 9085 0 Blue 0
9 PM Tue 29 29 N 11 5410 9085 0 Blue 0
10 PM Tue 28 28 N 11 5410 9085 0 Blue 0
11 PM Tue 26 26 N 7 5410 9085 0 Blue 0
12 Midnight Wed 25 25 N 7 5410 9085 0 Blue 0
1 AM Wed 24 24 N 7 5410 9085 0 Blue 0
2 AM Wed 24 24 N 7 5410 9085 0 Blue 0
3 AM Wed 23 23 N 7 5410 9085 0 Blue 0
4 AM Wed 23 23 N 7 5410 9085 0 Blue 0
5 AM Wed 22 22 N 7 5410 9085 0 Blue 0
6 AM Wed 21 21 N 7 5410 9085 0 Blue 0
7 AM Wed 21 21 N 7 5410 9085 0 Blue 0
8 AM Wed 26 26 N 7 5410 9085 0 Blue 0
9 AM Wed 34 35 N 7 5410 9085 0 Blue 0
10 AM Wed 42 44 N 7 5410 9085 0 Blue 0
11 AM Wed 46 50 NE 3 6532 9085 0 Blue 0
12 Noon Wed 48 53 NE 3 7252 9085 0 Blue 0
1 PM Wed 49 54 NE 3 7491 9085 0 Blue 0
2 PM Wed 51 55 NE 3 9182 9085 0 Blue 1
3 PM Wed 51 54 NE 3 7491 9085 0 Blue 0
4 PM Wed 49 51 NE 3 6773 9085 0 Blue 0
5 PM Wed 47 48 S 3 6048 9085 0 Blue 0
6 PM Wed 43 43 S 3 5410 9085 0 Blue 0
7 PM Wed 38 38 S 3 5410 9085 0 Blue 0
8 PM Wed 35 35 S 3 5410 9085 0 Blue 0
9 PM Wed 31 31 S 3 5410 9085 0 Blue 0
10 PM Wed 29 29 S 3 5410 9085 0 Blue 0
11 PM Wed 28 28 W 6 5410 9085 0 Blue 0
12 Midnight Thu 27 27 W 6 5410 9085 0 Blue 0
1 AM Thu 26 26 W 6 5410 9085 0 Blue 0
2 AM Thu 26 26 W 6 5410 9085 0 Blue 0
3 AM Thu 25 25 W 6 5410 9085 0 Blue 0
4 AM Thu 25 25 W 6 5410 9085 0 Blue 0
5 AM Thu 24 24 NW 5 5410 9085 0 Blue 0
6 AM Thu 23 23 NW 5 5410 9085 0 Blue 0
7 AM Thu 23 23 NW 5 5410 9085 0 Blue 0
8 AM Thu 29 29 NW 5 5410 9085 0 Blue 0
9 AM Thu 37 38 NW 5 5410 9085 0 Blue 0
10 AM Thu 46 48 NW 5 6048 9085 0 Blue 0
11 AM Thu 50 54 S 4 7491 9085 0 Blue 0
12 Noon Thu 53 58 S 4 12001 9085 0 Blue 4
1 PM Thu 54 59 S 4 13156 10467 1382 Blue 5
2 PM Thu 55 59 S 4 13156 10467 1382 Blue 5
3 PM Thu 56 59 S 4 13156 10467 1382 Blue 5
4 PM Thu 54 56 S 4 10545 9085 0 Blue 2
5 PM Thu 51 52 S 5 7013 9085 0 Blue 0
6 PM Thu 46 46 S 5 5560 9085 0 Blue 0
7 PM Thu 40 40 S 5 5410 9085 0 Blue 0
8 PM Thu 37 37 S 5 5410 9085 0 Blue 0
9 PM Thu 31 31 S 5 5410 9085 0 Blue 0
10 PM Thu 30 30 S 5 5410 9085 0 Blue 0
11 PM Thu 28 28 W 6 5410 9085 0 Blue 0
12 Midnight Fri 27 27 W 6 5410 9085 0 Blue 0
1 AM Fri 26 26 W 6 5410 9085 0 Blue 0
2 AM Fri 25 25 W 6 5410 9085 0 Blue 0
3 AM Fri 24 24 W 6 5410 9085 0 Blue 0
4 AM Fri 24 24 W 6 5410 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