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

Station:

KTUS

Date/Time:

12Z 23 SEP 2017

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 Sat 56 56 S 7 4744 5100 0 Blue 0
7 AM Sat 56 56 S 8 4744 5100 0 Blue 0
8 AM Sat 59 59 S 9 4744 5100 0 Blue 0
9 AM Sat 61 63 S 9 7184 5100 0 Blue 3
10 AM Sat 62 66 S 10 9208 7151 2051 Blue 6
11 AM Sat 65 70 S 12 10466 9546 4446 Blue 10
12 Noon Sat 67 73 S 12 11157 10428 5328 Blue 13
1 PM Sat 68 74 S 13 11341 10817 5717 Blue 14
2 PM Sat 70 75 SW 13 11732 10971 5871 Blue 15
3 PM Sat 70 74 SW 14 11341 10817 5717 Blue 14
4 PM Sat 69 71 SW 14 10848 9934 4834 Blue 11
5 PM Sat 69 69 SW 14 10258 9153 4053 Blue 9
6 PM Sat 70 70 SW 14 10466 9546 4446 Blue 10
7 PM Sat 68 68 SW 13 10049 8387 3287 Blue 8
8 PM Sat 65 65 W 12 8506 6733 1633 Blue 5
9 PM Sat 63 63 W 10 7184 5100 0 Blue 3
10 PM Sat 62 62 W 9 6758 5100 0 Blue 2
11 PM Sat 60 60 W 8 4766 5100 0 Blue 0
12 Midnight Sun 59 59 W 7 4744 5100 0 Blue 0
1 AM Sun 57 57 NW 6 4744 5100 0 Blue 0
2 AM Sun 55 55 NW 6 4744 5100 0 Blue 0
3 AM Sun 55 55 NW 5 4744 5100 0 Blue 0
4 AM Sun 54 54 NW 5 4744 5100 0 Blue 0
5 AM Sun 53 53 N 5 4744 5100 0 Blue 0
6 AM Sun 52 52 N 3 4744 5100 0 Blue 0
7 AM Sun 52 52 NW 3 4744 5100 0 Blue 0
8 AM Sun 56 57 NW 3 4744 5100 0 Blue 0
9 AM Sun 60 62 W 3 6758 5100 0 Blue 2
10 AM Sun 61 65 W 3 8506 6733 1633 Blue 5
11 AM Sun 64 69 SW 3 10258 9153 4053 Blue 9
12 Noon Sun 67 73 SW 3 11157 10428 5328 Blue 13
1 PM Sun 69 75 SW 5 11732 10971 5871 Blue 15
2 PM Sun 71 76 SW 5 12120 11125 6025 Blue 16
3 PM Sun 72 76 SW 6 12120 11125 6025 Blue 16
4 PM Sun 70 72 SW 7 11002 10221 5121 Blue 12
5 PM Sun 70 70 W 7 10466 9546 4446 Blue 10
6 PM Sun 72 72 W 7 11002 10221 5121 Blue 12
7 PM Sun 70 70 W 7 10466 9546 4446 Blue 10
8 PM Sun 67 67 W 7 9606 7588 2488 Blue 7
9 PM Sun 65 65 NW 6 8506 6733 1633 Blue 5
10 PM Sun 64 64 N 5 7627 5776 676 Blue 4
11 PM Sun 62 62 N 5 6758 5100 0 Blue 2
12 Midnight Mon 61 61 N 3 5808 5100 0 Blue 1
1 AM Mon 59 59 N 3 4744 5100 0 Blue 0
2 AM Mon 57 57 N 5 4744 5100 0 Blue 0
3 AM Mon 57 57 NE 5 4744 5100 0 Blue 0
4 AM Mon 56 56 NE 6 4744 5100 0 Blue 0
5 AM Mon 55 55 NE 6 4744 5100 0 Blue 0
6 AM Mon 54 54 NE 6 4744 5100 0 Blue 0
7 AM Mon 54 54 NE 6 4744 5100 0 Blue 0
8 AM Mon 58 59 NE 5 4744 5100 0 Blue 0
9 AM Mon 62 64 NE 3 7627 5776 676 Blue 4
10 AM Mon 63 67 NE 2 9606 7588 2488 Blue 7
11 AM Mon 66 71 NE 2 10848 9934 4834 Blue 11
12 Noon Mon 69 75 NE 1 11732 10971 5871 Blue 15
1 PM Mon 71 77 N 2 12507 11279 6179 Blue 17
2 PM Mon 73 78 N 2 12888 11645 6545 Blue 18
3 PM Mon 74 77 NW 3 12507 11279 6179 Blue 17
4 PM Mon 72 74 NW 5 11341 10817 5717 Blue 14
5 PM Mon 72 72 W 5 11002 10221 5121 Blue 12
6 PM Mon 74 74 W 6 11341 10817 5717 Blue 14
7 PM Mon 72 72 W 6 11002 10221 5121 Blue 12
8 PM Mon 69 69 NW 7 10258 9153 4053 Blue 9
9 PM Mon 68 68 N 7 10049 8387 3287 Blue 8
10 PM Mon 67 67 N 7 9606 7588 2488 Blue 7
11 PM Mon 65 65 NE 7 8506 6733 1633 Blue 5
12 Midnight Tue 64 64 NE 7 7627 5776 676 Blue 4
1 AM Tue 62 62 NE 7 6758 5100 0 Blue 2
2 AM Tue 61 61 NE 7 5808 5100 0 Blue 1
3 AM Tue 61 61 NE 7 5808 5100 0 Blue 1
4 AM Tue 60 60 NE 7 4766 5100 0 Blue 0
5 AM Tue 59 59 NE 7 4744 5100 0 Blue 0
6 AM Tue 58 58 NE 6 4744 5100 0 Blue 0
7 AM Tue 58 58 NE 7 4744 5100 0 Blue 0
8 AM Tue 62 63 E 7 7184 5100 0 Blue 3
9 AM Tue 65 67 E 7 9606 7588 2488 Blue 7
10 AM Tue 67 71 E 7 10848 9934 4834 Blue 11
11 AM Tue 70 75 SE 7 11732 10971 5871 Blue 15
12 Noon Tue 72 78 SE 7 12888 11645 6545 Blue 18
1 PM Tue 74 80 SE 7 13960 12410 7310 Blue 20
2 PM Tue 76 81 S 7 14244 12788 7688 White 21
3 PM Tue 77 81 S 7 14244 12788 7688 White 21
4 PM Tue 76 78 S 7 12888 11645 6545 Blue 18
5 PM Tue 75 75 SW 7 11732 10971 5871 Blue 15
6 PM Tue 77 77 SW 7 12507 11279 6179 Blue 17
7 PM Tue 75 75 SW 7 11732 10971 5871 Blue 15
8 PM Tue 72 72 S 7 11002 10221 5121 Blue 12
9 PM Tue 70 70 S 7 10466 9546 4446 Blue 10
10 PM Tue 69 69 S 7 10258 9153 4053 Blue 9
11 PM Tue 67 67 S 7 9606 7588 2488 Blue 7
12 Midnight Wed 66 66 S 6 9208 7151 2051 Blue 6
1 AM Wed 64 64 SE 6 7627 5776 676 Blue 4
2 AM Wed 62 62 SE 6 6758 5100 0 Blue 2
3 AM Wed 62 62 SE 6 6758 5100 0 Blue 2
4 AM Wed 61 61 SE 6 5808 5100 0 Blue 1
5 AM Wed 60 60 E 6 4766 5100 0 Blue 0
6 AM Wed 59 59 E 5 4744 5100 0 Blue 0
7 AM Wed 59 59 E 5 4744 5100 0 Blue 0
8 AM Wed 63 63 E 5 7184 5100 0 Blue 3
9 AM Wed 67 69 E 5 10258 9153 4053 Blue 9
10 AM Wed 68 71 E 5 10848 9934 4834 Blue 11
11 AM Wed 71 76 E 5 12120 11125 6025 Blue 16
12 Noon Wed 74 79 E 5 13307 12027 6927 Blue 19
1 PM Wed 76 81 E 5 14244 12788 7688 White 21
2 PM Wed 78 82 E 5 14453 13186 8086 White 22
3 PM Wed 79 82 E 5 14453 13186 8086 White 22
4 PM Wed 77 78 E 5 12888 11645 6545 Blue 18
5 PM Wed 77 77 E 5 12507 11279 6179 Blue 17
6 PM Wed 79 79 E 5 13307 12027 6927 Blue 19
7 PM Wed 77 77 E 6 12507 11279 6179 Blue 17
8 PM Wed 74 74 E 7 11341 10817 5717 Blue 14
9 PM Wed 72 72 E 8 11002 10221 5121 Blue 12
10 PM Wed 72 72 E 9 11002 10221 5121 Blue 12
11 PM Wed 70 70 E 10 10466 9546 4446 Blue 10
12 Midnight Thu 68 68 E 10 10049 8387 3287 Blue 8
1 AM Thu 67 67 E 12 9606 7588 2488 Blue 7
2 AM Thu 65 65 E 13 8506 6733 1633 Blue 5
3 AM Thu 65 65 E 14 8506 6733 1633 Blue 5
4 AM Thu 64 64 E 14 7627 5776 676 Blue 4
5 AM Thu 63 63 E 15 7184 5100 0 Blue 3
6 AM Thu 62 62 E 15 6758 5100 0 Blue 2
7 AM Thu 62 62 E 14 6758 5100 0 Blue 2
8 AM Thu 65 65 E 13 8506 6733 1633 Blue 5
9 AM Thu 69 70 E 12 10466 9546 4446 Blue 10
10 AM Thu 70 73 E 10 11157 10428 5328 Blue 13
11 AM Thu 73 77 E 9 12507 11279 6179 Blue 17
12 Noon Thu 75 79 E 8 13307 12027 6927 Blue 19
1 PM Thu 76 80 E 7 13960 12410 7310 Blue 20
2 PM Thu 79 83 E 6 14660 13722 8622 White 23
3 PM Thu 79 82 E 5 14453 13186 8086 White 22
4 PM Thu 78 79 E 3 13307 12027 6927 Blue 19
5 PM Thu 77 77 E 2 12507 11279 6179 Blue 17
6 PM Thu 79 79 E 1 13307 12027 6927 Blue 19
7 PM Thu 77 77 E 2 12507 11279 6179 Blue 17
8 PM Thu 74 74 E 2 11341 10817 5717 Blue 14
9 PM Thu 73 73 E 3 11157 10428 5328 Blue 13
10 PM Thu 72 72 E 3 11002 10221 5121 Blue 12
11 PM Thu 70 70 E 5 10466 9546 4446 Blue 10
12 Midnight Fri 69 69 E 6 10258 9153 4053 Blue 9
1 AM Fri 67 67 E 7 9606 7588 2488 Blue 7
2 AM Fri 66 66 E 8 9208 7151 2051 Blue 6
3 AM Fri 66 66 E 9 9208 7151 2051 Blue 6
4 AM Fri 65 65 E 10 8506 6733 1633 Blue 5
5 AM Fri 64 64 E 12 7627 5776 676 Blue 4

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