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

Station:

KNKX

Date/Time:

21 SEP 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 69 69 SE 5 3173 3900 0 Blue 0
6 AM Fri 71 71 SE 5 3173 3900 0 Blue 0
7 AM Fri 70 70 SE 5 3173 3900 0 Blue 0
8 AM Fri 76 76 E 3 3509 3900 0 Blue 0
9 AM Fri 78 80 SE 3 4364 3900 0 Blue 4
10 AM Fri 78 81 S 2 4757 3934 34 Blue 5
11 AM Fri 78 82 SW 5 5469 4146 246 Blue 6
12 Noon Fri 79 84 W 7 7364 4740 840 Blue 8
1 PM Fri 79 85 W 8 8888 5457 1557 Blue 9
2 PM Fri 79 84 W 8 7364 4740 840 Blue 8
3 PM Fri 79 83 W 9 5970 4358 458 Blue 7
4 PM Fri 79 81 W 9 4757 3934 34 Blue 5
5 PM Fri 78 79 W 8 4151 3900 0 Blue 3
6 PM Fri 75 75 W 6 3371 3900 0 Blue 0
7 PM Fri 74 74 NW 3 3242 3900 0 Blue 0
8 PM Fri 74 74 N 5 3242 3900 0 Blue 0
9 PM Fri 75 75 N 6 3371 3900 0 Blue 0
10 PM Fri 75 75 N 5 3371 3900 0 Blue 0
11 PM Fri 74 74 N 5 3242 3900 0 Blue 0
12 Midnight Sat 74 74 N 3 3242 3900 0 Blue 0
1 AM Sat 75 75 N 3 3371 3900 0 Blue 0
2 AM Sat 75 75 NE 3 3371 3900 0 Blue 0
3 AM Sat 75 75 NE 3 3371 3900 0 Blue 0
4 AM Sat 75 75 NE 3 3371 3900 0 Blue 0
5 AM Sat 74 74 E 5 3242 3900 0 Blue 0
6 AM Sat 76 76 E 5 3509 3900 0 Blue 0
7 AM Sat 75 75 E 5 3371 3900 0 Blue 0
8 AM Sat 81 81 E 5 4757 3934 34 Blue 5
9 AM Sat 83 84 SE 3 7364 4740 840 Blue 8
10 AM Sat 83 86 S 2 9313 5904 2004 Blue 10
11 AM Sat 83 87 SW 6 9731 6894 2994 Blue 11
12 Noon Sat 84 89 SW 8 10523 9235 5335 Blue 13
1 PM Sat 84 90 SW 9 10862 9648 5748 Blue 14
2 PM Sat 84 89 W 10 10523 9235 5335 Blue 13
3 PM Sat 84 88 W 10 10141 8813 4913 Blue 12
4 PM Sat 82 84 W 10 7364 4740 840 Blue 8
5 PM Sat 81 82 W 9 5469 4146 246 Blue 6
6 PM Sat 74 74 W 7 3242 3900 0 Blue 0
7 PM Sat 72 72 W 5 3173 3900 0 Blue 0
8 PM Sat 71 71 NW 3 3173 3900 0 Blue 0
9 PM Sat 73 73 NW 3 3173 3900 0 Blue 0
10 PM Sat 73 73 NW 3 3173 3900 0 Blue 0
11 PM Sat 72 72 NW 5 3173 3900 0 Blue 0
12 Midnight Sun 72 72 NW 5 3173 3900 0 Blue 0
1 AM Sun 73 73 N 5 3173 3900 0 Blue 0
2 AM Sun 72 72 N 5 3173 3900 0 Blue 0
3 AM Sun 74 74 N 6 3242 3900 0 Blue 0
4 AM Sun 74 74 NW 6 3242 3900 0 Blue 0
5 AM Sun 71 71 NW 7 3173 3900 0 Blue 0
6 AM Sun 73 73 NW 6 3173 3900 0 Blue 0
7 AM Sun 72 72 NW 6 3173 3900 0 Blue 0
8 AM Sun 76 76 NW 3 3509 3900 0 Blue 0
9 AM Sun 78 79 W 3 4151 3900 0 Blue 3
10 AM Sun 78 81 W 6 4757 3934 34 Blue 5
11 AM Sun 78 83 W 8 5970 4358 458 Blue 7
12 Noon Sun 79 85 W 9 8888 5457 1557 Blue 9
1 PM Sun 79 85 W 10 8888 5457 1557 Blue 9
2 PM Sun 79 85 W 13 8888 5457 1557 Blue 9
3 PM Sun 79 83 W 12 5970 4358 458 Blue 7
4 PM Sun 78 80 W 10 4364 3900 0 Blue 4
5 PM Sun 76 77 W 9 3723 3900 0 Blue 1
6 PM Sun 70 70 W 7 3173 3900 0 Blue 0
7 PM Sun 68 68 W 5 3173 3900 0 Blue 0
8 PM Sun 67 67 W 3 3173 3900 0 Blue 0
9 PM Sun 68 68 SW 2 3173 3900 0 Blue 0
10 PM Sun 68 68 SW 3 3173 3900 0 Blue 0
11 PM Sun 68 68 SW 2 3173 3900 0 Blue 0
12 Midnight Mon 68 68 SW 2 3173 3900 0 Blue 0
1 AM Mon 69 69 SW 2 3173 3900 0 Blue 0
2 AM Mon 68 68 SW 2 3173 3900 0 Blue 0
3 AM Mon 69 69 SW 2 3173 3900 0 Blue 0
4 AM Mon 70 70 SW 2 3173 3900 0 Blue 0
5 AM Mon 67 67 NW 8 3173 3900 0 Blue 0
6 AM Mon 69 69 NW 8 3173 3900 0 Blue 0
7 AM Mon 68 68 NW 8 3173 3900 0 Blue 0
8 AM Mon 74 74 N 5 3242 3900 0 Blue 0
9 AM Mon 76 78 N 5 3937 3900 0 Blue 2
10 AM Mon 76 79 N 5 4151 3900 0 Blue 3
11 AM Mon 76 81 W 7 4757 3934 34 Blue 5
12 Noon Mon 77 83 W 7 5970 4358 458 Blue 7
1 PM Mon 78 84 W 7 7364 4740 840 Blue 8
2 PM Mon 78 84 W 13 7364 4740 840 Blue 8
3 PM Mon 77 81 W 13 4757 3934 34 Blue 5
4 PM Mon 76 79 W 13 4151 3900 0 Blue 3
5 PM Mon 75 76 W 9 3509 3900 0 Blue 0
6 PM Mon 69 69 W 9 3173 3900 0 Blue 0
7 PM Mon 68 68 W 9 3173 3900 0 Blue 0
8 PM Mon 67 67 NW 5 3173 3900 0 Blue 0
9 PM Mon 68 68 NW 5 3173 3900 0 Blue 0
10 PM Mon 68 68 NW 5 3173 3900 0 Blue 0
11 PM Mon 68 68 N 6 3173 3900 0 Blue 0
12 Midnight Tue 68 68 N 6 3173 3900 0 Blue 0
1 AM Tue 68 68 N 6 3173 3900 0 Blue 0
2 AM Tue 68 68 N 5 3173 3900 0 Blue 0
3 AM Tue 69 69 N 5 3173 3900 0 Blue 0
4 AM Tue 69 69 N 5 3173 3900 0 Blue 0
5 AM Tue 67 67 NE 5 3173 3900 0 Blue 0
6 AM Tue 70 70 NE 5 3173 3900 0 Blue 0
7 AM Tue 68 68 NE 5 3173 3900 0 Blue 0
8 AM Tue 74 74 E 10 3242 3900 0 Blue 0
9 AM Tue 77 79 E 10 4151 3900 0 Blue 3
10 AM Tue 77 80 E 10 4364 3900 0 Blue 4
11 AM Tue 77 82 SE 5 5469 4146 246 Blue 6
12 Noon Tue 78 84 SE 5 7364 4740 840 Blue 8
1 PM Tue 79 85 SE 5 8888 5457 1557 Blue 9
2 PM Tue 79 85 W 6 8888 5457 1557 Blue 9
3 PM Tue 78 82 W 6 5469 4146 246 Blue 6
4 PM Tue 77 79 W 6 4151 3900 0 Blue 3
5 PM Tue 76 77 W 7 3723 3900 0 Blue 1
6 PM Tue 71 71 W 7 3173 3900 0 Blue 0
7 PM Tue 70 70 W 7 3173 3900 0 Blue 0
8 PM Tue 69 69 N 3 3173 3900 0 Blue 0
9 PM Tue 70 70 N 3 3173 3900 0 Blue 0
10 PM Tue 70 70 N 3 3173 3900 0 Blue 0
11 PM Tue 70 70 NE 3 3173 3900 0 Blue 0
12 Midnight Wed 70 70 NE 3 3173 3900 0 Blue 0
1 AM Wed 70 70 NE 3 3173 3900 0 Blue 0
2 AM Wed 70 70 NE 5 3173 3900 0 Blue 0
3 AM Wed 71 71 NE 5 3173 3900 0 Blue 0
4 AM Wed 71 71 NE 5 3173 3900 0 Blue 0
5 AM Wed 69 69 NE 5 3173 3900 0 Blue 0
6 AM Wed 71 71 NE 5 3173 3900 0 Blue 0
7 AM Wed 70 70 NE 5 3173 3900 0 Blue 0
8 AM Wed 76 76 E 7 3509 3900 0 Blue 0
9 AM Wed 78 79 E 7 4151 3900 0 Blue 3
10 AM Wed 78 81 E 7 4757 3934 34 Blue 5
11 AM Wed 78 83 S 3 5970 4358 458 Blue 7
12 Noon Wed 79 85 S 3 8888 5457 1557 Blue 9
1 PM Wed 80 86 S 3 9313 5904 2004 Blue 10
2 PM Wed 80 85 W 8 8888 5457 1557 Blue 9
3 PM Wed 79 83 W 8 5970 4358 458 Blue 7
4 PM Wed 78 80 W 8 4364 3900 0 Blue 4
5 PM Wed 77 78 W 7 3937 3900 0 Blue 2
6 PM Wed 71 71 W 7 3173 3900 0 Blue 0
7 PM Wed 70 70 W 7 3173 3900 0 Blue 0
8 PM Wed 69 69 N 2 3173 3900 0 Blue 0
9 PM Wed 70 70 N 2 3173 3900 0 Blue 0
10 PM Wed 70 70 N 2 3173 3900 0 Blue 0
11 PM Wed 70 70 N 5 3173 3900 0 Blue 0
12 Midnight Thu 70 70 N 5 3173 3900 0 Blue 0
1 AM Thu 70 70 N 5 3173 3900 0 Blue 0
2 AM Thu 70 70 N 3 3173 3900 0 Blue 0
3 AM Thu 71 71 N 3 3173 3900 0 Blue 0
4 AM Thu 71 71 N 3 3173 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