Detailed Predictions for: Humbolt
Launch Altitude (f): 5100
LZ Altitude (f): 2100
Sounding

Station:

KTUS

Date/Time:

20 AUG 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)
6 AM Tue 74 74 N 7 4534 5100 0 Blue 0
7 AM Tue 76 76 N 7 4534 5100 0 Blue 0
8 AM Tue 75 76 NE 7 4534 5100 0 Blue 0
9 AM Tue 80 83 NE 7 4534 5100 0 Blue 0
10 AM Tue 83 88 E 5 8413 5837 737 Blue 4
11 AM Tue 86 93 S 3 15968 11014 5914 Blue 9
12 Noon Tue 88 96 SW 3 17012 15795 10695 Blue 12
1 PM Tue 90 98 SW 5 18346 16483 11383 Blue 14
2 PM Tue 91 98 SW 7 18346 16483 11383 Blue 14
3 PM Tue 92 97 SW 9 18182 16264 11164 Blue 13
4 PM Tue 93 96 SW 10 17012 15795 10695 Blue 12
5 PM Tue 93 94 SW 12 16362 13615 8515 Blue 10
6 PM Tue 91 91 SW 12 13841 8323 3223 Blue 7
7 PM Tue 89 89 W 12 9819 6582 1482 Blue 5
8 PM Tue 85 85 W 12 5861 5100 0 Blue 1
9 PM Tue 83 83 W 12 4534 5100 0 Blue 0
10 PM Tue 82 82 W 10 4534 5100 0 Blue 0
11 PM Tue 81 81 N 9 4534 5100 0 Blue 0
12 Midnight Wed 80 80 N 8 4534 5100 0 Blue 0
1 AM Wed 79 79 N 8 4534 5100 0 Blue 0
2 AM Wed 78 78 N 7 4534 5100 0 Blue 0
3 AM Wed 78 78 N 6 4534 5100 0 Blue 0
4 AM Wed 77 77 N 6 4534 5100 0 Blue 0
5 AM Wed 76 76 N 6 4534 5100 0 Blue 0
6 AM Wed 76 76 N 6 4534 5100 0 Blue 0
7 AM Wed 76 76 N 6 4534 5100 0 Blue 0
8 AM Wed 78 79 NE 6 4534 5100 0 Blue 0
9 AM Wed 81 84 NE 6 5049 5100 0 Blue 0
10 AM Wed 84 89 E 6 9819 6582 1482 Blue 5
11 AM Wed 86 93 SE 7 15968 11014 5914 Blue 9
12 Noon Wed 89 97 S 9 18182 16264 11164 Blue 13
1 PM Wed 90 98 S 10 18346 16483 11383 Blue 14
2 PM Wed 91 98 S 12 18346 16483 11383 Blue 14
3 PM Wed 92 97 SW 13 18182 16264 11164 Blue 13
4 PM Wed 93 96 SW 14 17012 15795 10695 Blue 12
5 PM Wed 92 93 SW 15 15968 11014 5914 Blue 9
6 PM Wed 91 91 SW 15 13841 8323 3223 Blue 7
7 PM Wed 88 88 SW 15 8413 5837 737 Blue 4
8 PM Wed 85 85 SW 14 5861 5100 0 Blue 1
9 PM Wed 82 82 SW 13 4534 5100 0 Blue 0
10 PM Wed 81 81 SW 13 4534 5100 0 Blue 0
11 PM Wed 80 80 SW 12 4534 5100 0 Blue 0
12 Midnight Thu 80 80 SW 10 4534 5100 0 Blue 0
1 AM Thu 79 79 SW 10 4534 5100 0 Blue 0
2 AM Thu 78 78 SW 10 4534 5100 0 Blue 0
3 AM Thu 76 76 S 10 4534 5100 0 Blue 0
4 AM Thu 75 75 S 9 4534 5100 0 Blue 0
5 AM Thu 73 73 S 9 4534 5100 0 Blue 0
6 AM Thu 73 73 S 9 4534 5100 0 Blue 0
7 AM Thu 73 73 S 9 4534 5100 0 Blue 0
8 AM Thu 74 75 S 9 4534 5100 0 Blue 0
9 AM Thu 76 79 S 9 4534 5100 0 Blue 0
10 AM Thu 78 83 S 9 4534 5100 0 Blue 0
11 AM Thu 81 88 S 9 8413 5837 737 Blue 4
12 Noon Thu 83 91 S 9 13841 8323 3223 Blue 7
1 PM Thu 85 93 S 9 15968 11014 5914 Blue 9
2 PM Thu 87 94 S 10 16362 13615 8515 Blue 10
3 PM Thu 88 93 SW 12 15968 11014 5914 Blue 9
4 PM Thu 89 92 SW 12 15337 9577 4477 Blue 8
5 PM Thu 88 89 SW 13 9819 6582 1482 Blue 5
6 PM Thu 87 87 SW 14 7542 5100 0 Blue 3
7 PM Thu 85 85 SW 14 5861 5100 0 Blue 1
8 PM Thu 82 82 SW 14 4534 5100 0 Blue 0
9 PM Thu 80 80 SW 15 4534 5100 0 Blue 0
10 PM Thu 79 79 SW 15 4534 5100 0 Blue 0
11 PM Thu 78 78 SW 14 4534 5100 0 Blue 0
12 Midnight Fri 78 78 SW 14 4534 5100 0 Blue 0
1 AM Fri 77 77 SW 13 4534 5100 0 Blue 0
2 AM Fri 76 76 S 12 4534 5100 0 Blue 0
3 AM Fri 75 75 SE 10 4534 5100 0 Blue 0
4 AM Fri 74 74 E 9 4534 5100 0 Blue 0
5 AM Fri 73 73 E 8 4534 5100 0 Blue 0
6 AM Fri 73 73 NE 8 4534 5100 0 Blue 0
7 AM Fri 73 73 NE 7 4534 5100 0 Blue 0
8 AM Fri 73 74 E 7 4534 5100 0 Blue 0
9 AM Fri 74 76 SE 7 4534 5100 0 Blue 0
10 AM Fri 76 80 SE 7 4534 5100 0 Blue 0
11 AM Fri 79 85 S 7 5861 5100 0 Blue 1
12 Noon Fri 81 88 S 8 8413 5837 737 Blue 4
1 PM Fri 83 90 S 8 11277 7468 2368 Blue 6
2 PM Fri 84 90 S 9 11277 7468 2368 Blue 6
3 PM Fri 84 89 SW 9 9819 6582 1482 Blue 5
4 PM Fri 84 87 SW 10 7542 5100 0 Blue 3
5 PM Fri 84 85 SW 10 5861 5100 0 Blue 1
6 PM Fri 83 83 SW 12 4534 5100 0 Blue 0
7 PM Fri 81 81 SW 12 4534 5100 0 Blue 0
8 PM Fri 79 79 SW 10 4534 5100 0 Blue 0
9 PM Fri 77 77 SW 10 4534 5100 0 Blue 0
10 PM Fri 76 76 SW 10 4534 5100 0 Blue 0
11 PM Fri 75 75 SW 10 4534 5100 0 Blue 0
12 Midnight Sat 75 75 SW 9 4534 5100 0 Blue 0
1 AM Sat 75 75 SW 9 4534 5100 0 Blue 0
2 AM Sat 74 74 W 8 4534 5100 0 Blue 0
3 AM Sat 74 74 NW 8 4534 5100 0 Blue 0
4 AM Sat 73 73 NW 8 4534 5100 0 Blue 0
5 AM Sat 73 73 N 7 4534 5100 0 Blue 0
6 AM Sat 72 72 N 7 4534 5100 0 Blue 0
7 AM Sat 71 71 N 7 4534 5100 0 Blue 0
8 AM Sat 71 72 NW 7 4534 5100 0 Blue 0
9 AM Sat 72 75 NW 7 4534 5100 0 Blue 0
10 AM Sat 74 78 W 8 4534 5100 0 Blue 0
11 AM Sat 77 83 SW 8 4534 5100 0 Blue 0
12 Noon Sat 80 87 SW 9 7542 5100 0 Blue 3
1 PM Sat 82 89 SW 10 9819 6582 1482 Blue 5
2 PM Sat 83 90 SW 12 11277 7468 2368 Blue 6
3 PM Sat 84 89 SW 13 9819 6582 1482 Blue 5
4 PM Sat 85 88 SW 14 8413 5837 737 Blue 4
5 PM Sat 85 86 SW 15 6622 5100 0 Blue 2
6 PM Sat 84 84 SW 16 5049 5100 0 Blue 0
7 PM Sat 82 82 SW 16 4534 5100 0 Blue 0
8 PM Sat 79 79 SW 15 4534 5100 0 Blue 0
9 PM Sat 77 77 SW 14 4534 5100 0 Blue 0
10 PM Sat 76 76 SW 13 4534 5100 0 Blue 0
11 PM Sat 76 76 S 12 4534 5100 0 Blue 0
12 Midnight Sun 76 76 S 12 4534 5100 0 Blue 0
1 AM Sun 76 76 SW 10 4534 5100 0 Blue 0
2 AM Sun 76 76 W 9 4534 5100 0 Blue 0
3 AM Sun 75 75 W 8 4534 5100 0 Blue 0
4 AM Sun 74 74 NW 8 4534 5100 0 Blue 0
5 AM Sun 73 73 N 7 4534 5100 0 Blue 0
6 AM Sun 72 72 N 7 4534 5100 0 Blue 0
7 AM Sun 72 72 N 7 4534 5100 0 Blue 0
8 AM Sun 73 74 NW 7 4534 5100 0 Blue 0
9 AM Sun 74 76 W 7 4534 5100 0 Blue 0
10 AM Sun 75 78 W 8 4534 5100 0 Blue 0
11 AM Sun 77 82 SW 8 4534 5100 0 Blue 0
12 Noon Sun 79 84 SW 9 5049 5100 0 Blue 0
1 PM Sun 82 87 SW 9 7542 5100 0 Blue 3
2 PM Sun 83 87 SW 10 7542 5100 0 Blue 3
3 PM Sun 85 88 SW 12 8413 5837 737 Blue 4
4 PM Sun 86 88 SW 13 8413 5837 737 Blue 4
5 PM Sun 86 86 SW 14 6622 5100 0 Blue 2
6 PM Sun 85 85 SW 14 5861 5100 0 Blue 1
7 PM Sun 83 83 SW 14 4534 5100 0 Blue 0
8 PM Sun 80 80 W 14 4534 5100 0 Blue 0
9 PM Sun 78 78 W 14 4534 5100 0 Blue 0
10 PM Sun 77 77 W 13 4534 5100 0 Blue 0
11 PM Sun 77 77 W 13 4534 5100 0 Blue 0
12 Midnight Mon 77 77 W 12 4534 5100 0 Blue 0
1 AM Mon 77 77 W 10 4534 5100 0 Blue 0
2 AM Mon 76 76 SW 10 4534 5100 0 Blue 0
3 AM Mon 75 75 SW 9 4534 5100 0 Blue 0
4 AM Mon 74 74 S 8 4534 5100 0 Blue 0
5 AM Mon 73 73 S 8 4534 5100 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

Supported By: Alan Crouse ac_soaring@yahoo.com