Detailed Predictions for: Boomer Ridge
Launch Altitude (f): 5833
LZ Altitude (f): 4093
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 71 71 W 23 4915 5833 0 Blue 0
6 AM Wed 69 69 NW 17 4915 5833 0 Blue 0
7 AM Wed 71 71 NW 15 4915 5833 0 Blue 0
8 AM Wed 76 77 N 12 5200 5833 0 Blue 1
9 AM Wed 79 81 N 9 6825 5833 0 Blue 5
10 AM Wed 81 85 NE 7 9566 7508 1675 Blue 9
11 AM Wed 84 90 E 7 12560 10684 4851 Blue 14
12 Noon Wed 86 93 SE 8 14080 12427 6594 Blue 17
1 PM Wed 87 95 SE 8 14982 13482 7649 Blue 19
2 PM Wed 88 95 S 8 14982 13482 7649 Blue 19
3 PM Wed 89 95 SW 13 14982 13482 7649 Blue 19
4 PM Wed 89 93 SW 16 14080 12427 6594 Blue 17
5 PM Wed 88 90 W 17 12560 10684 4851 Blue 14
6 PM Wed 84 85 W 24 9566 7508 1675 Blue 9
7 PM Wed 80 80 W 25 6037 5833 0 Blue 4
8 PM Wed 76 76 W 26 4955 5833 0 Blue 0
9 PM Wed 75 75 W 26 4915 5833 0 Blue 0
10 PM Wed 73 73 W 28 4915 5833 0 Blue 0
11 PM Wed 73 73 W 25 4915 5833 0 Blue 0
12 Midnight Thu 72 72 W 26 4915 5833 0 Blue 0
1 AM Thu 72 72 W 23 4915 5833 0 Blue 0
2 AM Thu 71 71 W 18 4915 5833 0 Blue 0
3 AM Thu 71 71 W 23 4915 5833 0 Blue 0
4 AM Thu 70 70 W 21 4915 5833 0 Blue 0
5 AM Thu 70 70 NW 15 4915 5833 0 Blue 0
6 AM Thu 68 68 W 22 4915 5833 0 Blue 0
7 AM Thu 71 71 NW 20 4915 5833 0 Blue 0
8 AM Thu 75 76 NW 9 4955 5833 0 Blue 0
9 AM Thu 78 80 W 10 6037 5833 0 Blue 4
10 AM Thu 80 84 SE 12 8930 6783 950 Blue 8
11 AM Thu 82 87 SE 7 10797 8851 3018 Blue 11
12 Noon Thu 84 90 SE 7 12560 10684 4851 Blue 14
1 PM Thu 86 92 SE 7 13612 11868 6035 Blue 16
2 PM Thu 87 93 S 10 14080 12427 6594 Blue 17
3 PM Thu 88 93 S 10 14080 12427 6594 Blue 17
4 PM Thu 87 90 S 10 12560 10684 4851 Blue 14
5 PM Thu 86 88 W 20 11408 9478 3645 Blue 12
6 PM Thu 83 83 W 20 8264 6011 178 Blue 7
7 PM Thu 79 79 W 20 5719 5833 0 Blue 3
8 PM Thu 76 76 W 23 4955 5833 0 Blue 0
9 PM Thu 74 74 W 23 4915 5833 0 Blue 0
10 PM Thu 73 73 W 23 4915 5833 0 Blue 0
11 PM Thu 73 73 W 26 4915 5833 0 Blue 0
12 Midnight Fri 72 72 W 26 4915 5833 0 Blue 0
1 AM Fri 72 72 W 26 4915 5833 0 Blue 0
2 AM Fri 72 72 W 22 4915 5833 0 Blue 0
3 AM Fri 72 72 W 22 4915 5833 0 Blue 0
4 AM Fri 72 72 W 22 4915 5833 0 Blue 0
5 AM Fri 72 72 NW 20 4915 5833 0 Blue 0
6 AM Fri 73 73 NW 20 4915 5833 0 Blue 0
7 AM Fri 74 74 NW 20 4915 5833 0 Blue 0
8 AM Fri 76 76 S 13 4955 5833 0 Blue 0
9 AM Fri 78 80 S 13 6037 5833 0 Blue 4
10 AM Fri 80 84 S 13 8930 6783 950 Blue 8
11 AM Fri 82 87 SE 12 10797 8851 3018 Blue 11
12 Noon Fri 84 90 SE 12 12560 10684 4851 Blue 14
1 PM Fri 85 92 SE 12 13612 11868 6035 Blue 16
2 PM Fri 86 93 S 16 14080 12427 6594 Blue 17
3 PM Fri 87 93 S 16 14080 12427 6594 Blue 17
4 PM Fri 87 91 S 16 13106 11288 5455 Blue 15
5 PM Fri 86 88 S 18 11408 9478 3645 Blue 12
6 PM Fri 83 84 S 18 8930 6783 950 Blue 8
7 PM Fri 80 80 S 18 6037 5833 0 Blue 4
8 PM Fri 77 77 S 22 5200 5833 0 Blue 1
9 PM Fri 75 75 S 22 4915 5833 0 Blue 0
10 PM Fri 75 75 S 22 4915 5833 0 Blue 0
11 PM Fri 74 74 SW 24 4915 5833 0 Blue 0
12 Midnight Sat 74 74 SW 24 4915 5833 0 Blue 0
1 AM Sat 73 73 SW 24 4915 5833 0 Blue 0
2 AM Sat 73 73 W 21 4915 5833 0 Blue 0
3 AM Sat 72 72 W 21 4915 5833 0 Blue 0
4 AM Sat 72 72 W 21 4915 5833 0 Blue 0
5 AM Sat 72 72 NW 18 4915 5833 0 Blue 0
6 AM Sat 73 73 NW 18 4915 5833 0 Blue 0
7 AM Sat 75 75 NW 18 4915 5833 0 Blue 0
8 AM Sat 77 77 SW 12 5200 5833 0 Blue 1
9 AM Sat 79 81 SW 12 6825 5833 0 Blue 5
10 AM Sat 82 86 SW 12 10177 8196 2363 Blue 10
11 AM Sat 84 90 SE 12 12560 10684 4851 Blue 14
12 Noon Sat 86 93 SE 12 14080 12427 6594 Blue 17
1 PM Sat 87 94 SE 12 14536 12968 7135 Blue 18
2 PM Sat 88 95 S 16 14982 13482 7649 Blue 19
3 PM Sat 88 94 S 16 14536 12968 7135 Blue 18
4 PM Sat 88 92 S 16 13612 11868 6035 Blue 16
5 PM Sat 87 89 S 20 11995 10080 4247 Blue 13
6 PM Sat 84 84 S 20 8930 6783 950 Blue 8
7 PM Sat 81 81 S 20 6825 5833 0 Blue 5
8 PM Sat 78 78 SW 23 5499 5833 0 Blue 2
9 PM Sat 76 76 SW 23 4955 5833 0 Blue 0
10 PM Sat 76 76 SW 23 4955 5833 0 Blue 0
11 PM Sat 75 75 SW 26 4915 5833 0 Blue 0
12 Midnight Sun 74 74 SW 26 4915 5833 0 Blue 0
1 AM Sun 74 74 SW 26 4915 5833 0 Blue 0
2 AM Sun 74 74 W 23 4915 5833 0 Blue 0
3 AM Sun 74 74 W 23 4915 5833 0 Blue 0
4 AM Sun 74 74 W 23 4915 5833 0 Blue 0
5 AM Sun 74 74 W 22 4915 5833 0 Blue 0
6 AM Sun 75 75 W 22 4915 5833 0 Blue 0
7 AM Sun 76 76 W 22 4955 5833 0 Blue 0
8 AM Sun 78 79 NW 14 5719 5833 0 Blue 3
9 AM Sun 80 82 NW 14 7565 5833 0 Blue 6
10 AM Sun 83 87 NW 14 10797 8851 3018 Blue 11
11 AM Sun 85 90 SE 10 12560 10684 4851 Blue 14
12 Noon Sun 87 94 SE 10 14536 12968 7135 Blue 18
1 PM Sun 88 95 SE 10 14982 13482 7649 Blue 19
2 PM Sun 89 96 SW 14 15419 13945 8112 Blue 20
3 PM Sun 90 95 SW 14 14982 13482 7649 Blue 19
4 PM Sun 90 94 SW 14 14536 12968 7135 Blue 18
5 PM Sun 89 90 SW 18 12560 10684 4851 Blue 14
6 PM Sun 86 86 SW 18 10177 8196 2363 Blue 10
7 PM Sun 82 82 SW 18 7565 5833 0 Blue 6
8 PM Sun 79 79 W 25 5719 5833 0 Blue 3
9 PM Sun 78 78 W 25 5499 5833 0 Blue 2
10 PM Sun 77 77 W 25 5200 5833 0 Blue 1
11 PM Sun 77 77 W 26 5200 5833 0 Blue 1
12 Midnight Mon 77 77 W 26 5200 5833 0 Blue 1
1 AM Mon 76 76 W 26 4955 5833 0 Blue 0
2 AM Mon 76 76 W 25 4955 5833 0 Blue 0
3 AM Mon 75 75 W 25 4915 5833 0 Blue 0
4 AM Mon 75 75 W 25 4915 5833 0 Blue 0
5 AM Mon 75 75 W 22 4915 5833 0 Blue 0
6 AM Mon 76 76 W 22 4955 5833 0 Blue 0
7 AM Mon 77 77 W 22 5200 5833 0 Blue 1
8 AM Mon 79 79 W 14 5719 5833 0 Blue 3
9 AM Mon 81 81 W 14 6825 5833 0 Blue 5
10 AM Mon 83 84 W 14 8930 6783 950 Blue 8
11 AM Mon 85 87 S 9 10797 8851 3018 Blue 11
12 Noon Mon 87 90 S 9 12560 10684 4851 Blue 14
1 PM Mon 88 91 S 9 13106 11288 5455 Blue 15
2 PM Mon 89 92 S 14 13612 11868 6035 Blue 16
3 PM Mon 90 92 S 14 13612 11868 6035 Blue 16
4 PM Mon 90 91 S 14 13106 11288 5455 Blue 15
5 PM Mon 89 90 S 16 12560 10684 4851 Blue 14
6 PM Mon 86 86 S 16 10177 8196 2363 Blue 10
7 PM Mon 83 83 S 16 8264 6011 178 Blue 7
8 PM Mon 80 80 S 22 6037 5833 0 Blue 4
9 PM Mon 79 79 S 22 5719 5833 0 Blue 3
10 PM Mon 78 78 S 22 5499 5833 0 Blue 2
11 PM Mon 78 78 W 24 5499 5833 0 Blue 2
12 Midnight Tue 77 77 W 24 5200 5833 0 Blue 1
1 AM Tue 77 77 W 24 5200 5833 0 Blue 1
2 AM Tue 76 76 W 23 4955 5833 0 Blue 0
3 AM Tue 76 76 W 23 4955 5833 0 Blue 0
4 AM Tue 76 76 W 23 4955 5833 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