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

Station:

 KTUS

Date/Time:

 3 SEP 2010

Temp/Wind data from:

NOAA Digital Forecast

Time
(Local)		 High
Temp
Puddle
Temp
Wind
 (mph)		 Thermal
Ceiling
(ft)		 Soaring
Ceiling
(ft)		 Above
Launch
(ft)		 Thermal
Type		 Thermal
Index
(F)
6 AM Fri 72 72 NE 2 4383 5100 0 Blue 0
7 AM Fri 71 71 NE 2 4383 5100 0 Blue 0
8 AM Fri 70 71 NE 2 4383 5100 0 Blue 0
9 AM Fri 75 77 E 6 4383 5100 0 Blue 0
10 AM Fri 79 83 E 6 5363 5100 0 Blue 0
11 AM Fri 82 88 E 6 9695 6943 1843 Blue 5
12 Noon Fri 84 90 SE 10 17583 8550 3450 Blue 7
1 PM Fri 86 92 SE 10 17693 16559 11459 Blue 9
2 PM Fri 88 93 SE 10 17775 17554 12454 Blue 10
3 PM Fri 91 95 S 12 17940 17671 12571 Blue 12
4 PM Fri 92 94 S 12 17858 17622 12522 Blue 11
5 PM Fri 91 92 S 12 17693 16559 11459 Blue 9
6 PM Fri 89 89 S 7 16720 7668 2568 Blue 6
7 PM Fri 87 87 S 7 8676 6173 1073 Blue 4
8 PM Fri 84 84 S 7 6207 5100 0 Blue 1
9 PM Fri 81 81 SE 6 4383 5100 0 Blue 0
10 PM Fri 80 80 SE 6 4383 5100 0 Blue 0
11 PM Fri 78 78 SE 6 4383 5100 0 Blue 0
12 Midnight Sat 77 77 E 6 4383 5100 0 Blue 0
1 AM Sat 76 76 E 6 4383 5100 0 Blue 0
2 AM Sat 75 75 E 6 4383 5100 0 Blue 0
3 AM Sat 73 73 E 6 4383 5100 0 Blue 0
4 AM Sat 72 72 E 6 4383 5100 0 Blue 0
5 AM Sat 72 72 E 6 4383 5100 0 Blue 0
6 AM Sat 71 71 SE 6 4383 5100 0 Blue 0
7 AM Sat 71 71 SE 6 4383 5100 0 Blue 0
8 AM Sat 70 71 SE 6 4383 5100 0 Blue 0
9 AM Sat 75 77 SE 6 4383 5100 0 Blue 0
10 AM Sat 78 81 SE 6 4383 5100 0 Blue 0
11 AM Sat 81 86 SE 6 7731 5349 249 Blue 3
12 Noon Sat 84 90 S 6 17583 8550 3450 Blue 7
1 PM Sat 85 91 S 6 17646 9552 4452 Blue 8
2 PM Sat 87 92 S 6 17693 16559 11459 Blue 9
3 PM Sat 90 94 S 7 17858 17622 12522 Blue 11
4 PM Sat 91 93 S 7 17775 17554 12454 Blue 10
5 PM Sat 90 91 S 7 17646 9552 4452 Blue 8
6 PM Sat 88 88 SW 8 9695 6943 1843 Blue 5
7 PM Sat 86 86 SW 8 7731 5349 249 Blue 3
8 PM Sat 83 83 SW 8 5363 5100 0 Blue 0
9 PM Sat 80 80 SW 8 4383 5100 0 Blue 0
10 PM Sat 80 80 SW 8 4383 5100 0 Blue 0
11 PM Sat 77 77 SW 8 4383 5100 0 Blue 0
12 Midnight Sun 76 76 S 5 4383 5100 0 Blue 0
1 AM Sun 75 75 S 5 4383 5100 0 Blue 0
2 AM Sun 75 75 S 5 4383 5100 0 Blue 0
3 AM Sun 73 73 S 5 4383 5100 0 Blue 0
4 AM Sun 72 72 S 5 4383 5100 0 Blue 0
5 AM Sun 72 72 S 5 4383 5100 0 Blue 0
6 AM Sun 71 71 S 3 4383 5100 0 Blue 0
7 AM Sun 71 71 S 3 4383 5100 0 Blue 0
8 AM Sun 70 71 S 3 4383 5100 0 Blue 0
9 AM Sun 74 76 S 3 4383 5100 0 Blue 0
10 AM Sun 77 81 S 3 4383 5100 0 Blue 0
11 AM Sun 80 85 S 3 6993 5100 0 Blue 2
12 Noon Sun 82 88 S 9 9695 6943 1843 Blue 5
1 PM Sun 83 89 S 9 16720 7668 2568 Blue 6
2 PM Sun 85 90 S 9 17583 8550 3450 Blue 7
3 PM Sun 87 91 S 9 17646 9552 4452 Blue 8
4 PM Sun 88 90 S 9 17583 8550 3450 Blue 7
5 PM Sun 87 88 S 9 9695 6943 1843 Blue 5
6 PM Sun 86 86 SW 14 7731 5349 249 Blue 3
7 PM Sun 83 83 SW 14 5363 5100 0 Blue 0
8 PM Sun 81 81 SW 14 4383 5100 0 Blue 0
9 PM Sun 78 78 SW 14 4383 5100 0 Blue 0
10 PM Sun 77 77 SW 14 4383 5100 0 Blue 0
11 PM Sun 75 75 SW 14 4383 5100 0 Blue 0
12 Midnight Mon 74 74 S 10 4383 5100 0 Blue 0
1 AM Mon 73 73 S 10 4383 5100 0 Blue 0
2 AM Mon 72 72 S 10 4383 5100 0 Blue 0
3 AM Mon 71 71 S 10 4383 5100 0 Blue 0
4 AM Mon 70 70 S 10 4383 5100 0 Blue 0
5 AM Mon 69 69 S 10 4383 5100 0 Blue 0
6 AM Mon 69 69 S 5 4383 5100 0 Blue 0
7 AM Mon 69 69 S 5 4383 5100 0 Blue 0
8 AM Mon 68 69 S 5 4383 5100 0 Blue 0
9 AM Mon 71 73 S 5 4383 5100 0 Blue 0
10 AM Mon 74 78 S 5 4383 5100 0 Blue 0
11 AM Mon 77 82 S 5 4513 5100 0 Blue 0
12 Noon Mon 78 84 S 7 6207 5100 0 Blue 1
1 PM Mon 80 86 S 7 7731 5349 249 Blue 3
2 PM Mon 81 86 S 7 7731 5349 249 Blue 3
3 PM Mon 83 87 S 7 8676 6173 1073 Blue 4
4 PM Mon 84 86 S 7 7731 5349 249 Blue 3
5 PM Mon 83 84 S 7 6207 5100 0 Blue 1
6 PM Mon 82 82 SW 9 4513 5100 0 Blue 0
7 PM Mon 80 80 SW 9 4383 5100 0 Blue 0
8 PM Mon 77 77 SW 9 4383 5100 0 Blue 0
9 PM Mon 74 74 SW 9 4383 5100 0 Blue 0
10 PM Mon 74 74 SW 9 4383 5100 0 Blue 0
11 PM Mon 72 72 SW 9 4383 5100 0 Blue 0
12 Midnight Tue 71 71 S 7 4383 5100 0 Blue 0
1 AM Tue 70 70 S 7 4383 5100 0 Blue 0
2 AM Tue 69 69 S 7 4383 5100 0 Blue 0
3 AM Tue 68 68 S 7 4383 5100 0 Blue 0
4 AM Tue 67 67 S 7 4383 5100 0 Blue 0
5 AM Tue 66 66 S 7 4383 5100 0 Blue 0
6 AM Tue 66 66 SE 5 4383 5100 0 Blue 0
7 AM Tue 65 65 SE 5 4383 5100 0 Blue 0
8 AM Tue 65 66 SE 5 4383 5100 0 Blue 0
9 AM Tue 69 71 SE 5 4383 5100 0 Blue 0
10 AM Tue 72 76 SE 5 4383 5100 0 Blue 0
11 AM Tue 74 79 SE 5 4383 5100 0 Blue 0
12 Noon Tue 76 82 S 8 4513 5100 0 Blue 0
1 PM Tue 77 83 S 8 5363 5100 0 Blue 0
2 PM Tue 79 84 S 8 6207 5100 0 Blue 1
3 PM Tue 81 85 S 8 6993 5100 0 Blue 2
4 PM Tue 82 84 S 8 6207 5100 0 Blue 1
5 PM Tue 81 82 S 8 4513 5100 0 Blue 0
6 PM Tue 80 80 S 10 4383 5100 0 Blue 0
7 PM Tue 78 78 S 10 4383 5100 0 Blue 0
8 PM Tue 75 75 S 10 4383 5100 0 Blue 0
9 PM Tue 73 73 S 10 4383 5100 0 Blue 0
10 PM Tue 72 72 S 10 4383 5100 0 Blue 0
11 PM Tue 70 70 S 10 4383 5100 0 Blue 0
12 Midnight Wed 69 69 S 8 4383 5100 0 Blue 0
1 AM Wed 69 69 S 8 4383 5100 0 Blue 0
2 AM Wed 68 68 S 8 4383 5100 0 Blue 0
3 AM Wed 67 67 S 8 4383 5100 0 Blue 0
4 AM Wed 66 66 S 8 4383 5100 0 Blue 0
5 AM Wed 65 65 S 8 4383 5100 0 Blue 0
6 AM Wed 65 65 SE 6 4383 5100 0 Blue 0
7 AM Wed 64 64 SE 6 4383 5100 0 Blue 0
8 AM Wed 64 65 SE 6 4383 5100 0 Blue 0
9 AM Wed 68 71 SE 6 4383 5100 0 Blue 0
10 AM Wed 71 76 SE 6 4383 5100 0 Blue 0
11 AM Wed 74 80 SE 6 4383 5100 0 Blue 0
12 Noon Wed 76 82 S 9 4513 5100 0 Blue 0
1 PM Wed 77 83 S 9 5363 5100 0 Blue 0
2 PM Wed 79 84 S 9 6207 5100 0 Blue 1
3 PM Wed 81 85 S 9 6993 5100 0 Blue 2
4 PM Wed 82 84 S 9 6207 5100 0 Blue 1
5 PM Wed 81 82 S 9 4513 5100 0 Blue 0
6 PM Wed 80 80 SW 12 4383 5100 0 Blue 0
7 PM Wed 78 78 SW 12 4383 5100 0 Blue 0
8 PM Wed 75 75 SW 12 4383 5100 0 Blue 0
9 PM Wed 72 72 SW 12 4383 5100 0 Blue 0
10 PM Wed 72 72 SW 12 4383 5100 0 Blue 0
11 PM Wed 70 70 SW 12 4383 5100 0 Blue 0
12 Midnight Thu 69 69 S 10 4383 5100 0 Blue 0
1 AM Thu 68 68 S 10 4383 5100 0 Blue 0
2 AM Thu 67 67 S 10 4383 5100 0 Blue 0
3 AM Thu 66 66 S 10 4383 5100 0 Blue 0
4 AM Thu 65 65 S 10 4383 5100 0 Blue 0
5 AM Thu 64 64 S 10 4383 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