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

Station:

KNKX

Date/Time:

21 JUL 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 Sun 65 65 NE 2 3094 3900 0 Blue 0
6 AM Sun 69 69 NE 2 3094 3900 0 Blue 0
7 AM Sun 69 69 NE 2 3094 3900 0 Blue 0
8 AM Sun 76 77 NE 2 4276 3900 0 Blue 4
9 AM Sun 78 81 E 2 4810 4405 505 Blue 8
10 AM Sun 78 83 W 3 5076 4671 771 Blue 10
11 AM Sun 80 85 SW 6 5341 4937 1037 Blue 12
12 Noon Sun 81 88 W 8 5819 5333 1433 Blue 15
1 PM Sun 81 88 W 8 5819 5333 1433 Blue 15
2 PM Sun 81 87 W 9 5606 5201 1301 Blue 14
3 PM Sun 82 87 W 9 5606 5201 1301 Blue 14
4 PM Sun 81 85 W 9 5341 4937 1037 Blue 12
5 PM Sun 80 82 W 8 4943 4538 638 Blue 9
6 PM Sun 78 79 W 6 4543 4139 239 Blue 6
7 PM Sun 76 76 W 5 4142 3900 0 Blue 3
8 PM Sun 72 72 W 1 3492 3900 0 Blue 0
9 PM Sun 70 70 NW 2 3094 3900 0 Blue 0
10 PM Sun 69 69 N 2 3094 3900 0 Blue 0
11 PM Sun 69 69 N 2 3094 3900 0 Blue 0
12 Midnight Mon 71 71 N 2 3224 3900 0 Blue 0
1 AM Mon 69 69 N 2 3094 3900 0 Blue 0
2 AM Mon 70 70 NE 2 3094 3900 0 Blue 0
3 AM Mon 70 70 E 2 3094 3900 0 Blue 0
4 AM Mon 70 70 E 2 3094 3900 0 Blue 0
5 AM Mon 69 69 SE 2 3094 3900 0 Blue 0
6 AM Mon 72 72 SE 2 3492 3900 0 Blue 0
7 AM Mon 72 72 S 2 3492 3900 0 Blue 0
8 AM Mon 77 78 S 2 4409 4006 106 Blue 5
9 AM Mon 79 81 S 3 4810 4405 505 Blue 8
10 AM Mon 79 82 SW 5 4943 4538 638 Blue 9
11 AM Mon 80 84 SW 6 5208 4804 904 Blue 11
12 Noon Mon 81 86 SW 8 5473 5069 1169 Blue 13
1 PM Mon 81 86 W 9 5473 5069 1169 Blue 13
2 PM Mon 81 86 W 9 5473 5069 1169 Blue 13
3 PM Mon 82 86 W 9 5473 5069 1169 Blue 13
4 PM Mon 81 84 SW 9 5208 4804 904 Blue 11
5 PM Mon 80 81 SW 8 4810 4405 505 Blue 8
6 PM Mon 79 79 SW 7 4543 4139 239 Blue 6
7 PM Mon 77 77 W 5 4276 3900 0 Blue 4
8 PM Mon 74 74 W 3 3875 3900 0 Blue 1
9 PM Mon 72 72 W 2 3492 3900 0 Blue 0
10 PM Mon 71 71 W 2 3224 3900 0 Blue 0
11 PM Mon 71 71 W 2 3224 3900 0 Blue 0
12 Midnight Tue 73 73 NW 2 3741 3900 0 Blue 0
1 AM Tue 71 71 N 2 3224 3900 0 Blue 0
2 AM Tue 72 72 N 2 3492 3900 0 Blue 0
3 AM Tue 72 72 N 3 3492 3900 0 Blue 0
4 AM Tue 72 72 NE 3 3492 3900 0 Blue 0
5 AM Tue 71 71 NE 3 3224 3900 0 Blue 0
6 AM Tue 74 74 NE 2 3875 3900 0 Blue 1
7 AM Tue 74 74 NE 2 3875 3900 0 Blue 1
8 AM Tue 80 80 NE 2 4676 4272 372 Blue 7
9 AM Tue 82 84 N 2 5208 4804 904 Blue 11
10 AM Tue 82 85 NW 5 5341 4937 1037 Blue 12
11 AM Tue 83 86 W 6 5473 5069 1169 Blue 13
12 Noon Tue 84 88 W 8 5819 5333 1433 Blue 15
1 PM Tue 84 88 W 9 5819 5333 1433 Blue 15
2 PM Tue 84 88 W 10 5819 5333 1433 Blue 15
3 PM Tue 85 88 W 9 5819 5333 1433 Blue 15
4 PM Tue 84 86 NW 9 5473 5069 1169 Blue 13
5 PM Tue 83 84 NW 7 5208 4804 904 Blue 11
6 PM Tue 82 82 NW 6 4943 4538 638 Blue 9
7 PM Tue 79 79 NW 3 4543 4139 239 Blue 6
8 PM Tue 76 76 NW 2 4142 3900 0 Blue 3
9 PM Tue 74 74 NW 1 3875 3900 0 Blue 1
10 PM Tue 73 73 NW 1 3741 3900 0 Blue 0
11 PM Tue 73 73 NW 2 3741 3900 0 Blue 0
12 Midnight Wed 75 75 N 2 4009 3900 0 Blue 2
1 AM Wed 73 73 N 2 3741 3900 0 Blue 0
2 AM Wed 74 74 N 3 3875 3900 0 Blue 1
3 AM Wed 74 74 NE 5 3875 3900 0 Blue 1
4 AM Wed 74 74 E 6 3875 3900 0 Blue 1
5 AM Wed 73 73 E 6 3741 3900 0 Blue 0
6 AM Wed 75 75 E 6 4009 3900 0 Blue 2
7 AM Wed 76 76 E 6 4142 3900 0 Blue 3
8 AM Wed 80 81 E 13 4810 4405 505 Blue 8
9 AM Wed 81 83 E 13 5076 4671 771 Blue 10
10 AM Wed 82 85 E 13 5341 4937 1037 Blue 12
11 AM Wed 82 85 SW 6 5341 4937 1037 Blue 12
12 Noon Wed 83 87 SW 6 5606 5201 1301 Blue 14
1 PM Wed 84 88 SW 6 5819 5333 1433 Blue 15
2 PM Wed 83 87 NW 9 5606 5201 1301 Blue 14
3 PM Wed 84 87 NW 9 5606 5201 1301 Blue 14
4 PM Wed 83 85 NW 9 5341 4937 1037 Blue 12
5 PM Wed 82 83 SW 8 5076 4671 771 Blue 10
6 PM Wed 81 81 SW 8 4810 4405 505 Blue 8
7 PM Wed 79 79 SW 8 4543 4139 239 Blue 6
8 PM Wed 76 76 SW 2 4142 3900 0 Blue 3
9 PM Wed 74 74 SW 2 3875 3900 0 Blue 1
10 PM Wed 74 74 SW 2 3875 3900 0 Blue 1
11 PM Wed 74 74 NW 2 3875 3900 0 Blue 1
12 Midnight Thu 76 76 NW 2 4142 3900 0 Blue 3
1 AM Thu 74 74 NW 2 3875 3900 0 Blue 1
2 AM Thu 74 74 NW 2 3875 3900 0 Blue 1
3 AM Thu 75 75 NW 2 4009 3900 0 Blue 2
4 AM Thu 74 74 NW 2 3875 3900 0 Blue 1
5 AM Thu 74 74 W 2 3875 3900 0 Blue 1
6 AM Thu 76 76 W 2 4142 3900 0 Blue 3
7 AM Thu 77 77 W 2 4276 3900 0 Blue 4
8 AM Thu 81 82 NW 2 4943 4538 638 Blue 9
9 AM Thu 82 84 NW 2 5208 4804 904 Blue 11
10 AM Thu 82 85 NW 2 5341 4937 1037 Blue 12
11 AM Thu 83 88 W 7 5819 5333 1433 Blue 15
12 Noon Thu 84 90 W 7 6361 5597 1697 Blue 17
1 PM Thu 84 90 W 7 6361 5597 1697 Blue 17
2 PM Thu 84 90 W 10 6361 5597 1697 Blue 17
3 PM Thu 85 90 W 10 6361 5597 1697 Blue 17
4 PM Thu 84 87 W 10 5606 5201 1301 Blue 14
5 PM Thu 83 85 W 10 5341 4937 1037 Blue 12
6 PM Thu 81 82 W 10 4943 4538 638 Blue 9
7 PM Thu 78 78 W 10 4409 4006 106 Blue 5
8 PM Thu 74 74 W 3 3875 3900 0 Blue 1
9 PM Thu 72 72 W 3 3492 3900 0 Blue 0
10 PM Thu 71 71 W 3 3224 3900 0 Blue 0
11 PM Thu 71 71 NW 2 3224 3900 0 Blue 0
12 Midnight Fri 73 73 NW 2 3741 3900 0 Blue 0
1 AM Fri 71 71 NW 2 3224 3900 0 Blue 0
2 AM Fri 72 72 W 2 3492 3900 0 Blue 0
3 AM Fri 72 72 W 2 3492 3900 0 Blue 0
4 AM Fri 72 72 W 2 3492 3900 0 Blue 0
5 AM Fri 71 71 N 2 3224 3900 0 Blue 0
6 AM Fri 74 74 N 2 3875 3900 0 Blue 1
7 AM Fri 74 74 N 2 3875 3900 0 Blue 1
8 AM Fri 78 79 NW 2 4543 4139 239 Blue 6
9 AM Fri 80 82 NW 2 4943 4538 638 Blue 9
10 AM Fri 80 84 NW 2 5208 4804 904 Blue 11
11 AM Fri 81 87 W 7 5606 5201 1301 Blue 14
12 Noon Fri 82 89 W 7 6091 5465 1565 Blue 16
1 PM Fri 82 90 W 7 6361 5597 1697 Blue 17
2 PM Fri 82 89 W 12 6091 5465 1565 Blue 16
3 PM Fri 83 89 W 12 6091 5465 1565 Blue 16
4 PM Fri 82 86 W 12 5473 5069 1169 Blue 13
5 PM Fri 81 83 W 10 5076 4671 771 Blue 10
6 PM Fri 80 81 W 10 4810 4405 505 Blue 8
7 PM Fri 77 77 W 10 4276 3900 0 Blue 4
8 PM Fri 73 73 NW 5 3741 3900 0 Blue 0
9 PM Fri 71 71 NW 5 3224 3900 0 Blue 0
10 PM Fri 70 70 NW 5 3094 3900 0 Blue 0
11 PM Fri 70 70 NW 2 3094 3900 0 Blue 0
12 Midnight Sat 72 72 NW 2 3492 3900 0 Blue 0
1 AM Sat 70 70 NW 2 3094 3900 0 Blue 0
2 AM Sat 71 71 NW 3 3224 3900 0 Blue 0
3 AM Sat 71 71 NW 3 3224 3900 0 Blue 0
4 AM Sat 71 71 NW 3 3224 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