Detailed Predictions for: BJ
Launch Altitude (f): 582
LZ Altitude (f): 180
Sounding

Station:

KOTX

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 53 53 S 2 0 582 0 Blue 0
6 AM Tue 55 55 S 2 0 582 0 Blue 0
7 AM Tue 54 54 S 2 0 582 0 Blue 0
8 AM Tue 57 57 SW 0 0 582 0 Blue 0
9 AM Tue 62 63 SW 0 2427 2388 1806 Blue 2
10 AM Tue 63 64 SW 0 2450 2388 1806 Blue 3
11 AM Tue 68 69 SW 5 2563 2494 1912 Blue 8
12 Noon Tue 71 73 SW 5 2652 2584 2002 Blue 12
1 PM Tue 72 74 SW 5 2675 2607 2025 Blue 13
2 PM Tue 77 80 SW 8 2809 2741 2159 Blue 19
3 PM Tue 75 77 SW 8 2742 2674 2092 Blue 16
4 PM Tue 76 78 SW 8 2764 2696 2114 Blue 17
5 PM Tue 76 77 SW 8 2742 2674 2092 Blue 16
6 PM Tue 76 76 SW 8 2719 2651 2069 Blue 15
7 PM Tue 75 75 SW 8 2697 2629 2047 Blue 14
8 PM Tue 70 70 SW 6 2585 2517 1935 Blue 9
9 PM Tue 68 68 SW 6 2540 2472 1890 Blue 7
10 PM Tue 65 65 SW 6 2472 2404 1822 Blue 4
11 PM Tue 64 64 S 8 2450 2388 1806 Blue 3
12 Midnight Wed 64 64 S 8 2450 2388 1806 Blue 3
1 AM Wed 62 62 S 8 2405 2388 1806 Blue 1
2 AM Wed 61 61 SW 2 0 582 0 Blue 0
3 AM Wed 62 62 SW 2 2405 2388 1806 Blue 1
4 AM Wed 59 59 SW 2 0 582 0 Blue 0
5 AM Wed 59 59 SW 1 0 582 0 Blue 0
6 AM Wed 60 60 SW 1 0 582 0 Blue 0
7 AM Wed 60 60 SW 1 0 582 0 Blue 0
8 AM Wed 60 60 SW 1 0 582 0 Blue 0
9 AM Wed 62 62 SW 1 2405 2388 1806 Blue 1
10 AM Wed 62 62 SW 1 2405 2388 1806 Blue 1
11 AM Wed 63 63 W 2 2427 2388 1806 Blue 2
12 Noon Wed 64 64 W 2 2450 2388 1806 Blue 3
1 PM Wed 64 64 W 2 2450 2388 1806 Blue 3
2 PM Wed 65 65 SW 2 2472 2404 1822 Blue 4
3 PM Wed 64 64 SW 2 2450 2388 1806 Blue 3
4 PM Wed 65 65 SW 2 2472 2404 1822 Blue 4
5 PM Wed 65 65 S 5 2472 2404 1822 Blue 4
6 PM Wed 65 65 S 5 2472 2404 1822 Blue 4
7 PM Wed 64 64 S 5 2450 2388 1806 Blue 3
8 PM Wed 62 62 S 5 2405 2388 1806 Blue 1
9 PM Wed 60 60 S 5 0 582 0 Blue 0
10 PM Wed 59 59 S 5 0 582 0 Blue 0
11 PM Wed 58 58 S 6 0 582 0 Blue 0
12 Midnight Thu 58 58 S 6 0 582 0 Blue 0
1 AM Thu 57 57 S 6 0 582 0 Blue 0
2 AM Thu 56 56 S 6 0 582 0 Blue 0
3 AM Thu 57 57 S 6 0 582 0 Blue 0
4 AM Thu 56 56 S 6 0 582 0 Blue 0
5 AM Thu 56 56 SW 7 0 582 0 Blue 0
6 AM Thu 57 57 SW 7 0 582 0 Blue 0
7 AM Thu 56 56 SW 7 0 582 0 Blue 0
8 AM Thu 58 58 SW 7 0 582 0 Blue 0
9 AM Thu 60 60 SW 7 0 582 0 Blue 0
10 AM Thu 61 61 SW 7 0 582 0 Blue 0
11 AM Thu 64 65 SW 7 2472 2404 1822 Blue 4
12 Noon Thu 65 67 SW 7 2518 2449 1867 Blue 6
1 PM Thu 66 68 SW 7 2540 2472 1890 Blue 7
2 PM Thu 68 71 SW 7 2608 2539 1957 Blue 10
3 PM Thu 66 68 SW 7 2540 2472 1890 Blue 7
4 PM Thu 67 69 SW 7 2563 2494 1912 Blue 8
5 PM Thu 67 68 SW 3 2540 2472 1890 Blue 7
6 PM Thu 67 67 SW 3 2518 2449 1867 Blue 6
7 PM Thu 66 66 SW 3 2495 2426 1844 Blue 5
8 PM Thu 62 62 SW 3 2405 2388 1806 Blue 1
9 PM Thu 60 60 SW 3 0 582 0 Blue 0
10 PM Thu 57 57 SW 3 0 582 0 Blue 0
11 PM Thu 56 56 S 2 0 582 0 Blue 0
12 Midnight Fri 56 56 S 2 0 582 0 Blue 0
1 AM Fri 54 54 S 2 0 582 0 Blue 0
2 AM Fri 53 53 S 2 0 582 0 Blue 0
3 AM Fri 54 54 S 2 0 582 0 Blue 0
4 AM Fri 52 52 S 2 0 582 0 Blue 0
5 AM Fri 52 52 W 1 0 582 0 Blue 0
6 AM Fri 53 53 W 1 0 582 0 Blue 0
7 AM Fri 53 53 W 1 0 582 0 Blue 0
8 AM Fri 54 54 W 1 0 582 0 Blue 0
9 AM Fri 58 58 W 1 0 582 0 Blue 0
10 AM Fri 59 60 W 1 0 582 0 Blue 0
11 AM Fri 62 63 SW 8 2427 2388 1806 Blue 2
12 Noon Fri 64 65 SW 8 2472 2404 1822 Blue 4
1 PM Fri 65 66 SW 8 2495 2426 1844 Blue 5
2 PM Fri 68 69 SW 8 2563 2494 1912 Blue 8
3 PM Fri 66 67 SW 8 2518 2449 1867 Blue 6
4 PM Fri 67 67 SW 8 2518 2449 1867 Blue 6
5 PM Fri 67 67 SW 5 2518 2449 1867 Blue 6
6 PM Fri 67 67 SW 5 2518 2449 1867 Blue 6
7 PM Fri 66 66 SW 5 2495 2426 1844 Blue 5
8 PM Fri 62 62 SW 5 2405 2388 1806 Blue 1
9 PM Fri 60 60 SW 5 0 582 0 Blue 0
10 PM Fri 57 57 SW 5 0 582 0 Blue 0
11 PM Fri 56 56 SE 3 0 582 0 Blue 0
12 Midnight Sat 57 57 SE 3 0 582 0 Blue 0
1 AM Sat 55 55 SE 3 0 582 0 Blue 0
2 AM Sat 54 54 SE 3 0 582 0 Blue 0
3 AM Sat 55 55 SE 3 0 582 0 Blue 0
4 AM Sat 53 53 SE 3 0 582 0 Blue 0
5 AM Sat 53 53 SE 6 0 582 0 Blue 0
6 AM Sat 54 54 SE 6 0 582 0 Blue 0
7 AM Sat 53 53 SE 6 0 582 0 Blue 0
8 AM Sat 55 55 SE 6 0 582 0 Blue 0
9 AM Sat 59 59 SE 6 0 582 0 Blue 0
10 AM Sat 60 60 SE 6 0 582 0 Blue 0
11 AM Sat 62 63 W 7 2427 2388 1806 Blue 2
12 Noon Sat 64 66 W 7 2495 2426 1844 Blue 5
1 PM Sat 65 67 W 7 2518 2449 1867 Blue 6
2 PM Sat 68 70 W 7 2585 2517 1935 Blue 9
3 PM Sat 66 67 W 7 2518 2449 1867 Blue 6
4 PM Sat 67 68 W 7 2540 2472 1890 Blue 7
5 PM Sat 67 68 S 7 2540 2472 1890 Blue 7
6 PM Sat 67 67 S 7 2518 2449 1867 Blue 6
7 PM Sat 66 66 S 7 2495 2426 1844 Blue 5
8 PM Sat 62 62 S 7 2405 2388 1806 Blue 1
9 PM Sat 60 60 S 7 0 582 0 Blue 0
10 PM Sat 57 57 S 7 0 582 0 Blue 0
11 PM Sat 56 56 S 7 0 582 0 Blue 0
12 Midnight Sun 57 57 S 7 0 582 0 Blue 0
1 AM Sun 55 55 S 7 0 582 0 Blue 0
2 AM Sun 54 54 S 7 0 582 0 Blue 0
3 AM Sun 55 55 S 7 0 582 0 Blue 0
4 AM Sun 53 53 S 7 0 582 0 Blue 0
5 AM Sun 53 53 SW 5 0 582 0 Blue 0
6 AM Sun 54 54 SW 5 0 582 0 Blue 0
7 AM Sun 54 54 SW 5 0 582 0 Blue 0
8 AM Sun 55 55 SW 5 0 582 0 Blue 0
9 AM Sun 59 59 SW 5 0 582 0 Blue 0
10 AM Sun 60 61 SW 5 0 582 0 Blue 0
11 AM Sun 63 64 SW 7 2450 2388 1806 Blue 3
12 Noon Sun 65 67 SW 7 2518 2449 1867 Blue 6
1 PM Sun 66 68 SW 7 2540 2472 1890 Blue 7
2 PM Sun 69 71 SW 7 2608 2539 1957 Blue 10
3 PM Sun 67 68 SW 7 2540 2472 1890 Blue 7
4 PM Sun 68 69 SW 7 2563 2494 1912 Blue 8
5 PM Sun 68 69 SW 5 2563 2494 1912 Blue 8
6 PM Sun 68 68 SW 5 2540 2472 1890 Blue 7
7 PM Sun 67 67 SW 5 2518 2449 1867 Blue 6
8 PM Sun 62 62 SW 5 2405 2388 1806 Blue 1
9 PM Sun 60 60 SW 5 0 582 0 Blue 0
10 PM Sun 57 57 SW 5 0 582 0 Blue 0
11 PM Sun 56 56 SE 3 0 582 0 Blue 0
12 Midnight Mon 56 56 SE 3 0 582 0 Blue 0
1 AM Mon 54 54 SE 3 0 582 0 Blue 0
2 AM Mon 53 53 SE 3 0 582 0 Blue 0
3 AM Mon 54 54 SE 3 0 582 0 Blue 0
4 AM Mon 52 52 SE 3 0 582 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