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

Station:

KNKX

Date/Time:

23 SEP 2017

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 Sat 44 44 W 2 3422 3900 0 Blue 0
6 AM Sat 45 45 SW 2 3422 3900 0 Blue 0
7 AM Sat 44 44 SW 2 3422 3900 0 Blue 0
8 AM Sat 46 46 SW 2 3422 3900 0 Blue 0
9 AM Sat 51 52 SW 2 3422 3900 0 Blue 0
10 AM Sat 54 56 SW 3 4438 3900 0 Blue 1
11 AM Sat 57 61 W 7 5703 4944 1044 Blue 6
12 Noon Sat 60 64 W 8 6868 5674 1774 Blue 9
1 PM Sat 61 66 W 8 7619 6447 2547 Blue 11
2 PM Sat 61 65 W 10 7246 6063 2163 Blue 10
3 PM Sat 61 64 W 12 6868 5674 1774 Blue 9
4 PM Sat 61 63 W 12 6485 5314 1414 Blue 8
5 PM Sat 60 60 W 10 5328 4825 925 Blue 5
6 PM Sat 57 57 W 9 4830 3900 0 Blue 2
7 PM Sat 54 54 W 8 3499 3900 0 Blue 0
8 PM Sat 53 53 NW 6 3422 3900 0 Blue 0
9 PM Sat 53 53 NW 6 3422 3900 0 Blue 0
10 PM Sat 52 52 NW 6 3422 3900 0 Blue 0
11 PM Sat 53 53 N 8 3422 3900 0 Blue 0
12 Midnight Sun 52 52 N 9 3422 3900 0 Blue 0
1 AM Sun 52 52 N 9 3422 3900 0 Blue 0
2 AM Sun 52 52 NE 12 3422 3900 0 Blue 0
3 AM Sun 52 52 NE 12 3422 3900 0 Blue 0
4 AM Sun 52 52 NE 10 3422 3900 0 Blue 0
5 AM Sun 51 51 NE 12 3422 3900 0 Blue 0
6 AM Sun 52 52 NE 12 3422 3900 0 Blue 0
7 AM Sun 51 51 NE 12 3422 3900 0 Blue 0
8 AM Sun 54 54 E 12 3499 3900 0 Blue 0
9 AM Sun 59 61 E 10 5703 4944 1044 Blue 6
10 AM Sun 63 66 E 9 7619 6447 2547 Blue 11
11 AM Sun 66 71 SE 3 9503 8311 4411 Blue 16
12 Noon Sun 70 76 SE 2 10683 9933 6033 Blue 21
1 PM Sun 71 77 S 2 10948 10161 6261 White 22
2 PM Sun 71 76 W 6 10683 9933 6033 Blue 21
3 PM Sun 71 75 W 8 10437 9694 5794 Blue 20
4 PM Sun 71 73 W 8 9984 9214 5314 Blue 18
5 PM Sun 70 71 W 14 9503 8311 4411 Blue 16
6 PM Sun 65 65 W 13 7246 6063 2163 Blue 10
7 PM Sun 60 60 W 12 5328 4825 925 Blue 5
8 PM Sun 60 60 N 5 5328 4825 925 Blue 5
9 PM Sun 59 59 N 5 5100 4430 530 Blue 4
10 PM Sun 58 58 N 6 4950 3929 29 Blue 3
11 PM Sun 58 58 NE 12 4950 3929 29 Blue 3
12 Midnight Mon 58 58 NE 10 4950 3929 29 Blue 3
1 AM Mon 58 58 NE 12 4950 3929 29 Blue 3
2 AM Mon 57 57 NE 16 4830 3900 0 Blue 2
3 AM Mon 57 57 NE 15 4830 3900 0 Blue 2
4 AM Mon 57 57 NE 15 4830 3900 0 Blue 2
5 AM Mon 56 56 NE 14 4438 3900 0 Blue 1
6 AM Mon 57 57 NE 14 4830 3900 0 Blue 2
7 AM Mon 56 56 NE 14 4438 3900 0 Blue 1
8 AM Mon 59 59 NE 14 5100 4430 530 Blue 4
9 AM Mon 63 64 NE 14 6868 5674 1774 Blue 9
10 AM Mon 66 69 NE 14 9017 7568 3668 Blue 14
11 AM Mon 70 75 N 10 10437 9694 5794 Blue 20
12 Noon Mon 73 79 N 10 11367 10617 6717 White 24
1 PM Mon 74 80 N 10 11575 10887 6987 White 25
2 PM Mon 74 79 NW 5 11367 10617 6717 White 24
3 PM Mon 74 78 NW 5 11157 10385 6485 White 23
4 PM Mon 74 76 NW 5 10683 9933 6033 Blue 21
5 PM Mon 72 73 NW 9 9984 9214 5314 Blue 18
6 PM Mon 67 67 NW 9 7986 6826 2926 Blue 12
7 PM Mon 62 62 NW 9 6097 5087 1187 Blue 7
8 PM Mon 61 61 N 3 5703 4944 1044 Blue 6
9 PM Mon 60 60 N 3 5328 4825 925 Blue 5
10 PM Mon 59 59 N 3 5100 4430 530 Blue 4
11 PM Mon 60 60 NE 9 5328 4825 925 Blue 5
12 Midnight Tue 59 59 NE 9 5100 4430 530 Blue 4
1 AM Tue 59 59 NE 9 5100 4430 530 Blue 4
2 AM Tue 59 59 N 9 5100 4430 530 Blue 4
3 AM Tue 58 58 N 9 4950 3929 29 Blue 3
4 AM Tue 58 58 N 9 4950 3929 29 Blue 3
5 AM Tue 57 57 E 13 4830 3900 0 Blue 2
6 AM Tue 58 58 E 13 4950 3929 29 Blue 3
7 AM Tue 57 57 E 13 4830 3900 0 Blue 2
8 AM Tue 60 60 E 15 5328 4825 925 Blue 5
9 AM Tue 64 65 E 15 7246 6063 2163 Blue 10
10 AM Tue 68 71 E 15 9503 8311 4411 Blue 16
11 AM Tue 70 74 E 3 10212 9455 5555 Blue 19
12 Noon Tue 74 79 E 3 11367 10617 6717 White 24
1 PM Tue 75 81 E 3 11783 11155 7255 White 26
2 PM Tue 76 81 W 8 11783 11155 7255 White 26
3 PM Tue 76 80 W 8 11575 10887 6987 White 25
4 PM Tue 75 77 W 8 10948 10161 6261 White 22
5 PM Tue 73 74 W 14 10212 9455 5555 Blue 19
6 PM Tue 68 68 W 14 8376 7199 3299 Blue 13
7 PM Tue 64 64 W 14 6868 5674 1774 Blue 9
8 PM Tue 63 63 NW 6 6485 5314 1414 Blue 8
9 PM Tue 62 62 NW 6 6097 5087 1187 Blue 7
10 PM Tue 61 61 NW 6 5703 4944 1044 Blue 6
11 PM Tue 61 61 N 6 5703 4944 1044 Blue 6
12 Midnight Wed 61 61 N 6 5703 4944 1044 Blue 6
1 AM Wed 61 61 N 6 5703 4944 1044 Blue 6
2 AM Wed 60 60 NE 13 5328 4825 925 Blue 5
3 AM Wed 60 60 NE 13 5328 4825 925 Blue 5
4 AM Wed 60 60 NE 13 5328 4825 925 Blue 5
5 AM Wed 59 59 NE 16 5100 4430 530 Blue 4
6 AM Wed 60 60 NE 16 5328 4825 925 Blue 5
7 AM Wed 59 59 NE 16 5100 4430 530 Blue 4
8 AM Wed 62 62 E 16 6097 5087 1187 Blue 7
9 AM Wed 67 68 E 16 8376 7199 3299 Blue 13
10 AM Wed 70 73 E 16 9984 9214 5314 Blue 18
11 AM Wed 73 78 E 13 11157 10385 6485 White 23
12 Noon Wed 77 83 E 13 12189 11685 7785 White 28
1 PM Wed 78 84 E 13 12389 12389 8489 White 29
2 PM Wed 79 84 E 8 12389 12389 8489 White 29
3 PM Wed 79 83 E 8 12189 11685 7785 White 28
4 PM Wed 78 80 E 8 11575 10887 6987 White 25
5 PM Wed 77 78 W 13 11157 10385 6485 White 23
6 PM Wed 72 72 W 13 9744 8956 5056 Blue 17
7 PM Wed 67 67 W 13 7986 6826 2926 Blue 12
8 PM Wed 66 66 NW 5 7619 6447 2547 Blue 11
9 PM Wed 66 66 NW 5 7619 6447 2547 Blue 11
10 PM Wed 65 65 NW 5 7246 6063 2163 Blue 10
11 PM Wed 65 65 N 9 7246 6063 2163 Blue 10
12 Midnight Thu 65 65 N 9 7246 6063 2163 Blue 10
1 AM Thu 65 65 N 9 7246 6063 2163 Blue 10
2 AM Thu 64 64 NE 17 6868 5674 1774 Blue 9
3 AM Thu 64 64 NE 17 6868 5674 1774 Blue 9
4 AM Thu 64 64 NE 17 6868 5674 1774 Blue 9
5 AM Thu 63 63 NE 15 6485 5314 1414 Blue 8
6 AM Thu 64 64 NE 15 6868 5674 1774 Blue 9
7 AM Thu 63 63 NE 15 6485 5314 1414 Blue 8
8 AM Thu 65 65 NE 16 7246 6063 2163 Blue 10
9 AM Thu 70 71 NE 16 9503 8311 4411 Blue 16
10 AM Thu 72 75 NE 16 10437 9694 5794 Blue 20
11 AM Thu 75 80 NE 12 11575 10887 6987 White 25
12 Noon Thu 78 84 NE 12 12389 12389 8489 White 29
1 PM Thu 79 85 NE 12 12590 12590 8690 White 30
2 PM Thu 80 85 N 8 12590 12590 8690 White 30
3 PM Thu 80 84 N 8 12389 12389 8489 White 29
4 PM Thu 79 81 N 8 11783 11155 7255 White 26
5 PM Thu 78 79 NW 14 11367 10617 6717 White 24
6 PM Thu 73 73 NW 14 9984 9214 5314 Blue 18
7 PM Thu 69 69 NW 14 9017 7568 3668 Blue 14
8 PM Thu 68 68 N 6 8376 7199 3299 Blue 13
9 PM Thu 68 68 N 6 8376 7199 3299 Blue 13
10 PM Thu 67 67 N 6 7986 6826 2926 Blue 12
11 PM Thu 67 67 N 9 7986 6826 2926 Blue 12
12 Midnight Fri 66 66 N 9 7619 6447 2547 Blue 11
1 AM Fri 67 67 N 9 7986 6826 2926 Blue 12
2 AM Fri 66 66 NE 15 7619 6447 2547 Blue 11
3 AM Fri 66 66 NE 15 7619 6447 2547 Blue 11
4 AM Fri 66 66 NE 15 7619 6447 2547 Blue 11

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