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

Station:

KTUS

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)
6 AM Wed 67 67 S 5 3412 5100 0 Blue 0
7 AM Wed 68 68 S 5 3412 5100 0 Blue 0
8 AM Wed 68 69 S 5 3412 5100 0 Blue 0
9 AM Wed 71 73 SE 6 4099 5100 0 Blue 0
10 AM Wed 74 78 S 7 9041 5100 0 Blue 3
11 AM Wed 76 82 S 10 12599 9541 4441 White 7
12 Noon Wed 79 85 S 13 13232 13232 8132 White 10
1 PM Wed 80 86 S 14 13444 13444 8344 White 11
2 PM Wed 82 87 S 15 13650 13650 8550 White 12
3 PM Wed 82 86 SW 15 13444 13444 8344 White 11
4 PM Wed 82 84 SW 16 13022 13022 7922 White 9
5 PM Wed 81 82 SW 16 12599 9541 4441 White 7
6 PM Wed 79 79 SW 15 9678 5372 272 Blue 4
7 PM Wed 76 76 SW 13 5429 5100 0 Blue 1
8 PM Wed 73 73 SW 10 4099 5100 0 Blue 0
9 PM Wed 72 72 SW 9 3614 5100 0 Blue 0
10 PM Wed 72 72 SW 9 3614 5100 0 Blue 0
11 PM Wed 71 71 SW 9 3412 5100 0 Blue 0
12 Midnight Thu 70 70 SW 10 3412 5100 0 Blue 0
1 AM Thu 70 70 SW 10 3412 5100 0 Blue 0
2 AM Thu 69 69 SW 10 3412 5100 0 Blue 0
3 AM Thu 69 69 SW 10 3412 5100 0 Blue 0
4 AM Thu 68 68 SW 9 3412 5100 0 Blue 0
5 AM Thu 67 67 S 8 3412 5100 0 Blue 0
6 AM Thu 66 66 S 8 3412 5100 0 Blue 0
7 AM Thu 66 66 S 7 3412 5100 0 Blue 0
8 AM Thu 66 67 S 7 3412 5100 0 Blue 0
9 AM Thu 69 71 S 9 3412 5100 0 Blue 0
10 AM Thu 72 76 S 12 5429 5100 0 Blue 1
11 AM Thu 74 79 S 14 9678 5372 272 Blue 4
12 Noon Thu 76 82 S 17 12599 9541 4441 White 7
1 PM Thu 78 84 S 20 13022 13022 7922 White 9
2 PM Thu 80 85 S 21 13232 13232 8132 White 10
3 PM Thu 81 85 S 21 13232 13232 8132 White 10
4 PM Thu 81 83 S 22 12811 12811 7711 White 8
5 PM Thu 79 80 SW 22 12176 7548 2448 White 5
6 PM Thu 77 77 SW 22 7697 5100 0 Blue 2
7 PM Thu 74 74 SW 20 4574 5100 0 Blue 0
8 PM Thu 72 72 SW 17 3614 5100 0 Blue 0
9 PM Thu 70 70 SW 15 3412 5100 0 Blue 0
10 PM Thu 69 69 SW 13 3412 5100 0 Blue 0
11 PM Thu 68 68 SW 12 3412 5100 0 Blue 0
12 Midnight Fri 68 68 SW 10 3412 5100 0 Blue 0
1 AM Fri 67 67 SW 9 3412 5100 0 Blue 0
2 AM Fri 66 66 S 8 3412 5100 0 Blue 0
3 AM Fri 65 65 S 8 3412 5100 0 Blue 0
4 AM Fri 64 64 S 7 3412 5100 0 Blue 0
5 AM Fri 63 63 S 6 3412 5100 0 Blue 0
6 AM Fri 62 62 S 5 3412 5100 0 Blue 0
7 AM Fri 62 62 S 6 3412 5100 0 Blue 0
8 AM Fri 63 64 S 6 3412 5100 0 Blue 0
9 AM Fri 65 67 S 7 3412 5100 0 Blue 0
10 AM Fri 68 72 S 9 3614 5100 0 Blue 0
11 AM Fri 70 76 S 10 5429 5100 0 Blue 1
12 Noon Fri 73 79 S 12 9678 5372 272 Blue 4
1 PM Fri 75 81 S 12 12388 8963 3863 White 6
2 PM Fri 76 81 S 13 12388 8963 3863 White 6
3 PM Fri 77 81 S 13 12388 8963 3863 White 6
4 PM Fri 77 79 SW 13 9678 5372 272 Blue 4
5 PM Fri 76 77 SW 12 7697 5100 0 Blue 2
6 PM Fri 74 74 SW 12 4574 5100 0 Blue 0
7 PM Fri 72 72 SW 10 3614 5100 0 Blue 0
8 PM Fri 69 69 SW 8 3412 5100 0 Blue 0
9 PM Fri 67 67 SW 7 3412 5100 0 Blue 0
10 PM Fri 66 66 SW 5 3412 5100 0 Blue 0
11 PM Fri 65 65 SW 3 3412 5100 0 Blue 0
12 Midnight Sat 65 65 SW 2 3412 5100 0 Blue 0
1 AM Sat 65 65 SW 1 3412 5100 0 Blue 0
2 AM Sat 64 64 SW 1 3412 5100 0 Blue 0
3 AM Sat 63 63 S 1 3412 5100 0 Blue 0
4 AM Sat 62 62 S 1 3412 5100 0 Blue 0
5 AM Sat 61 61 SE 1 3412 5100 0 Blue 0
6 AM Sat 61 61 SE 2 3412 5100 0 Blue 0
7 AM Sat 61 61 SE 3 3412 5100 0 Blue 0
8 AM Sat 63 64 SE 5 3412 5100 0 Blue 0
9 AM Sat 65 67 S 6 3412 5100 0 Blue 0
10 AM Sat 68 72 S 7 3614 5100 0 Blue 0
11 AM Sat 71 76 S 8 5429 5100 0 Blue 1
12 Noon Sat 74 80 S 9 12176 7548 2448 White 5
1 PM Sat 76 82 S 9 12599 9541 4441 White 7
2 PM Sat 77 82 S 10 12599 9541 4441 White 7
3 PM Sat 78 82 S 10 12599 9541 4441 White 7
4 PM Sat 78 80 SW 10 12176 7548 2448 White 5
5 PM Sat 78 79 SW 10 9678 5372 272 Blue 4
6 PM Sat 76 76 SW 9 5429 5100 0 Blue 1
7 PM Sat 73 73 SW 8 4099 5100 0 Blue 0
8 PM Sat 70 70 W 7 3412 5100 0 Blue 0
9 PM Sat 67 67 W 5 3412 5100 0 Blue 0
10 PM Sat 66 66 W 3 3412 5100 0 Blue 0
11 PM Sat 65 65 NW 2 3412 5100 0 Blue 0
12 Midnight Sun 65 65 NW 1 3412 5100 0 Blue 0
1 AM Sun 65 65 NW 0 3412 5100 0 Blue 0
2 AM Sun 64 64 N 0 3412 5100 0 Blue 0
3 AM Sun 63 63 N 0 3412 5100 0 Blue 0
4 AM Sun 62 62 N 0 3412 5100 0 Blue 0
5 AM Sun 61 61 N 1 3412 5100 0 Blue 0
6 AM Sun 61 61 N 1 3412 5100 0 Blue 0
7 AM Sun 62 62 NE 2 3412 5100 0 Blue 0
8 AM Sun 63 64 E 2 3412 5100 0 Blue 0
9 AM Sun 65 67 E 3 3412 5100 0 Blue 0
10 AM Sun 68 72 SE 3 3614 5100 0 Blue 0
11 AM Sun 71 76 S 5 5429 5100 0 Blue 1
12 Noon Sun 74 80 S 6 12176 7548 2448 White 5
1 PM Sun 76 82 S 7 12599 9541 4441 White 7
2 PM Sun 78 83 S 8 12811 12811 7711 White 8
3 PM Sun 79 82 S 10 12599 9541 4441 White 7
4 PM Sun 79 81 S 12 12388 8963 3863 White 6
5 PM Sun 78 78 SW 13 9041 5100 0 Blue 3
6 PM Sun 76 76 SW 13 5429 5100 0 Blue 1
7 PM Sun 73 73 SW 13 4099 5100 0 Blue 0
8 PM Sun 70 70 SW 12 3412 5100 0 Blue 0
9 PM Sun 68 68 SW 10 3412 5100 0 Blue 0
10 PM Sun 67 67 SW 9 3412 5100 0 Blue 0
11 PM Sun 66 66 SW 8 3412 5100 0 Blue 0
12 Midnight Mon 66 66 SW 8 3412 5100 0 Blue 0
1 AM Mon 66 66 SW 7 3412 5100 0 Blue 0
2 AM Mon 65 65 S 7 3412 5100 0 Blue 0
3 AM Mon 65 65 S 7 3412 5100 0 Blue 0
4 AM Mon 65 65 S 7 3412 5100 0 Blue 0
5 AM Mon 64 64 S 7 3412 5100 0 Blue 0
6 AM Mon 64 64 SE 8 3412 5100 0 Blue 0
7 AM Mon 64 64 SE 9 3412 5100 0 Blue 0
8 AM Mon 64 64 S 12 3412 5100 0 Blue 0
9 AM Mon 65 66 S 13 3412 5100 0 Blue 0
10 AM Mon 67 68 S 15 3412 5100 0 Blue 0
11 AM Mon 69 71 S 17 3412 5100 0 Blue 0
12 Noon Mon 71 74 S 18 4574 5100 0 Blue 0
1 PM Mon 73 75 S 20 5007 5100 0 Blue 0
2 PM Mon 74 76 S 21 5429 5100 0 Blue 1
3 PM Mon 75 76 S 22 5429 5100 0 Blue 1
4 PM Mon 75 75 S 23 5007 5100 0 Blue 0
5 PM Mon 74 74 S 23 4574 5100 0 Blue 0
6 PM Mon 73 73 S 22 4099 5100 0 Blue 0
7 PM Mon 70 70 S 21 3412 5100 0 Blue 0
8 PM Mon 68 68 S 20 3412 5100 0 Blue 0
9 PM Mon 66 66 S 17 3412 5100 0 Blue 0
10 PM Mon 65 65 S 15 3412 5100 0 Blue 0
11 PM Mon 65 65 S 13 3412 5100 0 Blue 0
12 Midnight Tue 65 65 SE 10 3412 5100 0 Blue 0
1 AM Tue 64 64 SE 9 3412 5100 0 Blue 0
2 AM Tue 64 64 SE 8 3412 5100 0 Blue 0
3 AM Tue 63 63 E 7 3412 5100 0 Blue 0
4 AM Tue 62 62 E 7 3412 5100 0 Blue 0
5 AM Tue 62 62 NE 7 3412 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