Detailed Predictions for: Big Black
Launch Altitude (f): 3900
LZ Altitude (f): 1645
Sounding

Station:

KNKX

Date/Time:

20 JUL 2018

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 Fri 70 70 N 2 3366 3900 0 Blue 0
6 AM Fri 70 70 N 1 3366 3900 0 Blue 0
7 AM Fri 70 70 N 1 3366 3900 0 Blue 0
8 AM Fri 71 72 W 2 3577 3900 0 Blue 0
9 AM Fri 72 74 W 2 4156 3900 0 Blue 0
10 AM Fri 73 77 W 3 4684 4149 249 Blue 3
11 AM Fri 75 79 W 7 5302 4517 617 Blue 5
12 Noon Fri 76 81 W 8 5867 5003 1103 Blue 7
1 PM Fri 78 83 W 8 6425 5567 1667 Blue 9
2 PM Fri 77 82 W 10 6147 5286 1386 Blue 8
3 PM Fri 77 81 W 10 5867 5003 1103 Blue 7
4 PM Fri 76 79 W 10 5302 4517 617 Blue 5
5 PM Fri 74 75 W 9 4361 3900 0 Blue 1
6 PM Fri 73 73 W 8 3867 3900 0 Blue 0
7 PM Fri 71 71 W 8 3366 3900 0 Blue 0
8 PM Fri 70 70 W 3 3366 3900 0 Blue 0
9 PM Fri 69 69 W 3 3366 3900 0 Blue 0
10 PM Fri 69 69 NW 2 3366 3900 0 Blue 0
11 PM Fri 68 68 NW 2 3366 3900 0 Blue 0
12 Midnight Sat 68 68 NW 2 3366 3900 0 Blue 0
1 AM Sat 68 68 NW 1 3366 3900 0 Blue 0
2 AM Sat 68 68 N 1 3366 3900 0 Blue 0
3 AM Sat 68 68 N 1 3366 3900 0 Blue 0
4 AM Sat 68 68 N 1 3366 3900 0 Blue 0
5 AM Sat 68 68 N 1 3366 3900 0 Blue 0
6 AM Sat 69 69 N 1 3366 3900 0 Blue 0
7 AM Sat 70 70 N 1 3366 3900 0 Blue 0
8 AM Sat 71 72 W 1 3577 3900 0 Blue 0
9 AM Sat 73 75 W 2 4361 3900 0 Blue 1
10 AM Sat 74 78 W 2 5017 4356 456 Blue 4
11 AM Sat 75 80 W 7 5585 4677 777 Blue 6
12 Noon Sat 77 83 W 7 6425 5567 1667 Blue 9
1 PM Sat 78 85 W 8 6830 6123 2223 Blue 11
2 PM Sat 78 84 W 10 6685 5846 1946 Blue 10
3 PM Sat 78 83 W 10 6425 5567 1667 Blue 9
4 PM Sat 77 81 W 10 5867 5003 1103 Blue 7
5 PM Sat 75 77 W 9 4684 4149 249 Blue 3
6 PM Sat 73 73 W 8 3867 3900 0 Blue 0
7 PM Sat 72 72 W 8 3577 3900 0 Blue 0
8 PM Sat 70 70 W 5 3366 3900 0 Blue 0
9 PM Sat 69 69 NW 3 3366 3900 0 Blue 0
10 PM Sat 69 69 NW 3 3366 3900 0 Blue 0
11 PM Sat 69 69 NW 3 3366 3900 0 Blue 0
12 Midnight Sun 69 69 NW 3 3366 3900 0 Blue 0
1 AM Sun 70 70 N 3 3366 3900 0 Blue 0
2 AM Sun 70 70 N 3 3366 3900 0 Blue 0
3 AM Sun 70 70 N 5 3366 3900 0 Blue 0
4 AM Sun 70 70 N 5 3366 3900 0 Blue 0
5 AM Sun 70 70 N 6 3366 3900 0 Blue 0
6 AM Sun 72 72 N 6 3577 3900 0 Blue 0
7 AM Sun 74 74 N 3 4156 3900 0 Blue 0
8 AM Sun 75 76 NW 2 4523 3900 0 Blue 2
9 AM Sun 77 79 NW 3 5302 4517 617 Blue 5
10 AM Sun 78 82 NW 3 6147 5286 1386 Blue 8
11 AM Sun 79 85 W 7 6830 6123 2223 Blue 11
12 Noon Sun 81 88 W 8 8435 6815 2915 Blue 14
1 PM Sun 83 91 W 8 9523 8334 4434 Blue 17
2 PM Sun 83 90 W 10 9186 7683 3783 Blue 16
3 PM Sun 84 90 W 10 9186 7683 3783 Blue 16
4 PM Sun 82 86 W 9 7078 6399 2499 Blue 12
5 PM Sun 80 82 W 8 6147 5286 1386 Blue 8
6 PM Sun 79 80 W 7 5585 4677 777 Blue 6
7 PM Sun 77 77 NW 5 4684 4149 249 Blue 3
8 PM Sun 76 76 NW 3 4523 3900 0 Blue 2
9 PM Sun 76 76 NW 5 4523 3900 0 Blue 2
10 PM Sun 75 75 NW 5 4361 3900 0 Blue 1
11 PM Sun 75 75 NW 6 4361 3900 0 Blue 1
12 Midnight Mon 75 75 NW 6 4361 3900 0 Blue 1
1 AM Mon 76 76 NW 6 4523 3900 0 Blue 2
2 AM Mon 76 76 NW 6 4523 3900 0 Blue 2
3 AM Mon 75 75 NW 6 4361 3900 0 Blue 1
4 AM Mon 74 74 N 6 4156 3900 0 Blue 0
5 AM Mon 75 75 N 6 4361 3900 0 Blue 1
6 AM Mon 78 78 N 6 5017 4356 456 Blue 4
7 AM Mon 83 83 N 6 6425 5567 1667 Blue 9
8 AM Mon 88 89 N 3 8845 6998 3098 Blue 15
9 AM Mon 90 92 N 3 9859 8786 4886 Blue 18
10 AM Mon 90 94 N 3 10555 9459 5559 Blue 19
11 AM Mon 90 96 SW 6 11684 10133 6233 White 21
12 Noon Mon 90 97 SW 6 11893 10475 6575 White 22
1 PM Mon 91 99 SW 6 12312 11170 7270 White 24
2 PM Mon 91 98 W 9 12104 10825 6925 White 23
3 PM Mon 92 98 W 9 12104 10825 6925 White 23
4 PM Mon 93 97 W 9 11893 10475 6575 White 22
5 PM Mon 92 94 W 10 10555 9459 5559 Blue 19
6 PM Mon 90 91 W 10 9523 8334 4434 Blue 17
7 PM Mon 85 85 W 10 6830 6123 2223 Blue 11
8 PM Mon 82 82 W 5 6147 5286 1386 Blue 8
9 PM Mon 80 80 W 5 5585 4677 777 Blue 6
10 PM Mon 79 79 W 5 5302 4517 617 Blue 5
11 PM Mon 79 79 NW 5 5302 4517 617 Blue 5
12 Midnight Tue 80 80 NW 5 5585 4677 777 Blue 6
1 AM Tue 81 81 NW 5 5867 5003 1103 Blue 7
2 AM Tue 81 81 NW 7 5867 5003 1103 Blue 7
3 AM Tue 80 80 NW 7 5585 4677 777 Blue 6
4 AM Tue 79 79 NW 7 5302 4517 617 Blue 5
5 AM Tue 80 80 N 6 5585 4677 777 Blue 6
6 AM Tue 83 83 N 6 6425 5567 1667 Blue 9
7 AM Tue 88 88 N 6 8435 6815 2915 Blue 14
8 AM Tue 91 92 NW 3 9859 8786 4886 Blue 18
9 AM Tue 92 95 NW 3 10908 9790 5890 Blue 20
10 AM Tue 91 95 NW 3 10908 9790 5890 Blue 20
11 AM Tue 91 97 W 7 11893 10475 6575 White 22
12 Noon Tue 92 99 W 7 12312 11170 7270 White 24
1 PM Tue 94 101 W 7 12728 12728 8828 White 26
2 PM Tue 96 103 W 10 13141 13141 9241 White 28
3 PM Tue 96 102 W 10 12935 12935 9035 White 27
4 PM Tue 95 99 W 10 12312 11170 7270 White 24
5 PM Tue 93 95 W 10 10908 9790 5890 Blue 20
6 PM Tue 91 92 W 10 9859 8786 4886 Blue 18
7 PM Tue 88 88 W 10 8435 6815 2915 Blue 14
8 PM Tue 86 86 W 5 7078 6399 2499 Blue 12
9 PM Tue 85 85 W 5 6830 6123 2223 Blue 11
10 PM Tue 84 84 W 5 6685 5846 1946 Blue 10
11 PM Tue 83 83 NW 5 6425 5567 1667 Blue 9
12 Midnight Wed 83 83 NW 5 6425 5567 1667 Blue 9
1 AM Wed 82 82 NW 5 6147 5286 1386 Blue 8
2 AM Wed 82 82 N 7 6147 5286 1386 Blue 8
3 AM Wed 81 81 N 7 5867 5003 1103 Blue 7
4 AM Wed 81 81 N 7 5867 5003 1103 Blue 7
5 AM Wed 82 82 N 7 6147 5286 1386 Blue 8
6 AM Wed 84 84 N 7 6685 5846 1946 Blue 10
7 AM Wed 86 86 N 7 7078 6399 2499 Blue 12
8 AM Wed 89 90 NW 5 9186 7683 3783 Blue 16
9 AM Wed 90 93 NW 5 10207 9124 5224 Blue 18
10 AM Wed 91 95 NW 5 10908 9790 5890 Blue 20
11 AM Wed 92 98 W 8 12104 10825 6925 White 23
12 Noon Wed 93 101 W 8 12728 12728 8828 White 26
1 PM Wed 94 102 W 8 12935 12935 9035 White 27
2 PM Wed 95 102 W 13 12935 12935 9035 White 27
3 PM Wed 94 100 W 13 12522 12322 8422 White 25
4 PM Wed 92 96 W 13 11684 10133 6233 White 21
5 PM Wed 90 92 W 9 9859 8786 4886 Blue 18
6 PM Wed 88 89 W 9 8845 6998 3098 Blue 15
7 PM Wed 86 86 W 9 7078 6399 2499 Blue 12
8 PM Wed 84 84 W 5 6685 5846 1946 Blue 10
9 PM Wed 82 82 W 5 6147 5286 1386 Blue 8
10 PM Wed 81 81 W 5 5867 5003 1103 Blue 7
11 PM Wed 80 80 NW 3 5585 4677 777 Blue 6
12 Midnight Thu 80 80 NW 3 5585 4677 777 Blue 6
1 AM Thu 81 81 NW 3 5867 5003 1103 Blue 7
2 AM Thu 81 81 N 6 5867 5003 1103 Blue 7
3 AM Thu 80 80 N 6 5585 4677 777 Blue 6
4 AM Thu 79 79 N 6 5302 4517 617 Blue 5

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