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

Station:

KNKX

Date/Time:

18 SEP 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 58 58 SE 3 3123 3900 0 Blue 0
6 AM Wed 59 59 SE 3 3123 3900 0 Blue 0
7 AM Wed 61 61 SE 3 3123 3900 0 Blue 0
8 AM Wed 63 63 SE 2 3123 3900 0 Blue 0
9 AM Wed 65 66 SE 3 3484 3900 0 Blue 0
10 AM Wed 66 69 S 5 4190 3900 0 Blue 2
11 AM Wed 68 73 SW 8 5086 4444 544 Blue 6
12 Noon Wed 70 76 SW 9 5404 5081 1181 Blue 9
1 PM Wed 72 78 SW 10 5910 5292 1392 Blue 11
2 PM Wed 71 77 SW 13 5576 5186 1286 Blue 10
3 PM Wed 71 75 SW 13 5298 4948 1048 Blue 8
4 PM Wed 69 72 W 13 4957 4183 283 Blue 5
5 PM Wed 66 67 W 12 3659 3900 0 Blue 0
6 PM Wed 64 64 W 9 3198 3900 0 Blue 0
7 PM Wed 62 62 W 6 3123 3900 0 Blue 0
8 PM Wed 61 61 SW 3 3123 3900 0 Blue 0
9 PM Wed 60 60 S 3 3123 3900 0 Blue 0
10 PM Wed 59 59 SE 3 3123 3900 0 Blue 0
11 PM Wed 59 59 SE 3 3123 3900 0 Blue 0
12 Midnight Thu 58 58 S 3 3123 3900 0 Blue 0
1 AM Thu 58 58 SE 3 3123 3900 0 Blue 0
2 AM Thu 57 57 SE 3 3123 3900 0 Blue 0
3 AM Thu 56 56 SE 3 3123 3900 0 Blue 0
4 AM Thu 54 54 S 3 3123 3900 0 Blue 0
5 AM Thu 54 54 S 3 3123 3900 0 Blue 0
6 AM Thu 54 54 S 3 3123 3900 0 Blue 0
7 AM Thu 56 56 S 3 3123 3900 0 Blue 0
8 AM Thu 58 58 S 3 3123 3900 0 Blue 0
9 AM Thu 59 60 S 6 3123 3900 0 Blue 0
10 AM Thu 61 64 SW 8 3198 3900 0 Blue 0
11 AM Thu 63 68 SW 10 3925 3900 0 Blue 1
12 Noon Thu 65 71 SW 13 4715 3921 21 Blue 4
1 PM Thu 66 72 SW 15 4957 4183 283 Blue 5
2 PM Thu 66 72 W 16 4957 4183 283 Blue 5
3 PM Thu 66 70 W 16 4453 3900 0 Blue 3
4 PM Thu 65 68 W 15 3925 3900 0 Blue 1
5 PM Thu 62 63 W 14 3123 3900 0 Blue 0
6 PM Thu 59 59 SW 12 3123 3900 0 Blue 0
7 PM Thu 56 56 SW 8 3123 3900 0 Blue 0
8 PM Thu 54 54 SW 6 3123 3900 0 Blue 0
9 PM Thu 54 54 SW 5 3123 3900 0 Blue 0
10 PM Thu 54 54 S 5 3123 3900 0 Blue 0
11 PM Thu 54 54 SE 5 3123 3900 0 Blue 0
12 Midnight Fri 54 54 SE 5 3123 3900 0 Blue 0
1 AM Fri 54 54 E 3 3123 3900 0 Blue 0
2 AM Fri 53 53 NE 3 3123 3900 0 Blue 0
3 AM Fri 52 52 NE 3 3123 3900 0 Blue 0
4 AM Fri 52 52 N 5 3123 3900 0 Blue 0
5 AM Fri 52 52 N 5 3123 3900 0 Blue 0
6 AM Fri 54 54 N 3 3123 3900 0 Blue 0
7 AM Fri 56 56 N 3 3123 3900 0 Blue 0
8 AM Fri 58 58 N 3 3123 3900 0 Blue 0
9 AM Fri 60 62 N 5 3123 3900 0 Blue 0
10 AM Fri 62 65 W 6 3341 3900 0 Blue 0
11 AM Fri 66 71 W 7 4715 3921 21 Blue 4
12 Noon Fri 69 75 W 8 5298 4948 1048 Blue 8
1 PM Fri 72 78 W 9 5910 5292 1392 Blue 11
2 PM Fri 73 79 W 10 6369 5397 1497 Blue 12
3 PM Fri 73 77 W 10 5576 5186 1286 Blue 10
4 PM Fri 70 73 W 10 5086 4444 544 Blue 6
5 PM Fri 66 67 W 9 3659 3900 0 Blue 0
6 PM Fri 63 63 NW 7 3123 3900 0 Blue 0
7 PM Fri 61 61 NW 5 3123 3900 0 Blue 0
8 PM Fri 60 60 NW 2 3123 3900 0 Blue 0
9 PM Fri 60 60 N 2 3123 3900 0 Blue 0
10 PM Fri 60 60 N 2 3123 3900 0 Blue 0
11 PM Fri 60 60 N 3 3123 3900 0 Blue 0
12 Midnight Sat 61 61 N 3 3123 3900 0 Blue 0
1 AM Sat 61 61 N 3 3123 3900 0 Blue 0
2 AM Sat 61 61 N 3 3123 3900 0 Blue 0
3 AM Sat 61 61 N 3 3123 3900 0 Blue 0
4 AM Sat 61 61 NE 3 3123 3900 0 Blue 0
5 AM Sat 62 62 NE 3 3123 3900 0 Blue 0
6 AM Sat 64 64 NE 3 3198 3900 0 Blue 0
7 AM Sat 67 67 NE 3 3659 3900 0 Blue 0
8 AM Sat 70 70 E 6 4453 3900 0 Blue 3
9 AM Sat 72 73 E 6 5086 4444 544 Blue 6
10 AM Sat 73 76 E 6 5404 5081 1181 Blue 9
11 AM Sat 75 80 E 7 6911 5553 1653 Blue 13
12 Noon Sat 77 83 E 7 8448 6853 2953 Blue 16
1 PM Sat 78 84 E 7 8854 7372 3472 Blue 17
2 PM Sat 78 84 SE 8 8854 7372 3472 Blue 17
3 PM Sat 78 82 SE 8 7949 6319 2419 Blue 15
4 PM Sat 75 78 SE 8 5910 5292 1392 Blue 11
5 PM Sat 72 73 W 8 5086 4444 544 Blue 6
6 PM Sat 69 69 W 8 4190 3900 0 Blue 2
7 PM Sat 66 66 W 8 3484 3900 0 Blue 0
8 PM Sat 64 64 E 2 3198 3900 0 Blue 0
9 PM Sat 64 64 E 2 3198 3900 0 Blue 0
10 PM Sat 65 65 E 2 3341 3900 0 Blue 0
11 PM Sat 66 66 SE 3 3484 3900 0 Blue 0
12 Midnight Sun 67 67 SE 3 3659 3900 0 Blue 0
1 AM Sun 67 67 SE 3 3659 3900 0 Blue 0
2 AM Sun 67 67 SE 5 3659 3900 0 Blue 0
3 AM Sun 66 66 SE 5 3484 3900 0 Blue 0
4 AM Sun 65 65 SE 5 3341 3900 0 Blue 0
5 AM Sun 66 66 SE 7 3484 3900 0 Blue 0
6 AM Sun 68 68 SE 7 3925 3900 0 Blue 1
7 AM Sun 72 72 SE 7 4957 4183 283 Blue 5
8 AM Sun 76 76 SE 7 5404 5081 1181 Blue 9
9 AM Sun 78 79 SE 7 6369 5397 1497 Blue 12
10 AM Sun 78 81 SE 7 7438 5884 1984 Blue 14
11 AM Sun 78 82 SW 8 7949 6319 2419 Blue 15
12 Noon Sun 79 84 SW 8 8854 7372 3472 Blue 17
1 PM Sun 78 83 SW 8 8448 6853 2953 Blue 16
2 PM Sun 78 83 SW 13 8448 6853 2953 Blue 16
3 PM Sun 77 81 SW 13 7438 5884 1984 Blue 14
4 PM Sun 76 78 SW 13 5910 5292 1392 Blue 11
5 PM Sun 74 75 SW 12 5298 4948 1048 Blue 8
6 PM Sun 73 73 SW 12 5086 4444 544 Blue 6
7 PM Sun 71 71 SW 12 4715 3921 21 Blue 4
8 PM Sun 70 70 SW 2 4453 3900 0 Blue 3
9 PM Sun 69 69 SW 2 4190 3900 0 Blue 2
10 PM Sun 68 68 SW 2 3925 3900 0 Blue 1
11 PM Sun 68 68 S 3 3925 3900 0 Blue 1
12 Midnight Mon 67 67 S 3 3659 3900 0 Blue 0
1 AM Mon 65 65 S 3 3341 3900 0 Blue 0
2 AM Mon 64 64 S 5 3198 3900 0 Blue 0
3 AM Mon 63 63 S 5 3123 3900 0 Blue 0
4 AM Mon 62 62 S 5 3123 3900 0 Blue 0
5 AM Mon 62 62 S 5 3123 3900 0 Blue 0
6 AM Mon 61 61 S 5 3123 3900 0 Blue 0
7 AM Mon 60 60 S 5 3123 3900 0 Blue 0
8 AM Mon 60 60 S 8 3123 3900 0 Blue 0
9 AM Mon 61 62 S 8 3123 3900 0 Blue 0
10 AM Mon 62 65 S 8 3341 3900 0 Blue 0
11 AM Mon 65 69 SW 13 4190 3900 0 Blue 2
12 Noon Mon 68 73 SW 13 5086 4444 544 Blue 6
1 PM Mon 70 75 SW 13 5298 4948 1048 Blue 8
2 PM Mon 72 76 SW 16 5404 5081 1181 Blue 9
3 PM Mon 71 74 SW 16 5192 4704 804 Blue 7
4 PM Mon 71 73 SW 16 5086 4444 544 Blue 6
5 PM Mon 69 70 SW 14 4453 3900 0 Blue 3
6 PM Mon 66 66 SW 14 3484 3900 0 Blue 0
7 PM Mon 64 64 SW 14 3198 3900 0 Blue 0
8 PM Mon 62 62 SW 6 3123 3900 0 Blue 0
9 PM Mon 60 60 SW 6 3123 3900 0 Blue 0
10 PM Mon 60 60 SW 6 3123 3900 0 Blue 0
11 PM Mon 60 60 S 5 3123 3900 0 Blue 0
12 Midnight Tue 60 60 S 5 3123 3900 0 Blue 0
1 AM Tue 60 60 S 5 3123 3900 0 Blue 0
2 AM Tue 59 59 S 6 3123 3900 0 Blue 0
3 AM Tue 58 58 S 6 3123 3900 0 Blue 0
4 AM Tue 58 58 S 6 3123 3900 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