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

Station:

KTUS

Date/Time:

18 SEP 2018

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 76 76 SW 2 3615 5100 0 Blue 0
7 AM Tue 79 79 SW 2 5924 5100 0 Blue 2
8 AM Tue 78 79 S 3 5924 5100 0 Blue 2
9 AM Tue 80 82 S 3 7727 5913 813 Blue 5
10 AM Tue 81 85 S 5 9592 7665 2565 Blue 8
11 AM Tue 82 88 S 6 12410 9529 4429 White 11
12 Noon Tue 83 89 S 7 12621 10800 5700 White 12
1 PM Tue 85 91 SW 9 13043 13043 7943 White 14
2 PM Tue 86 91 SW 10 13043 13043 7943 White 14
3 PM Tue 86 90 SW 12 12833 12833 7733 White 13
4 PM Tue 86 88 SW 13 12410 9529 4429 White 11
5 PM Tue 86 86 SW 14 11021 8341 3241 Blue 9
6 PM Tue 84 84 SW 14 9051 6952 1852 Blue 7
7 PM Tue 82 82 SW 13 7727 5913 813 Blue 5
8 PM Tue 80 80 W 12 6248 5263 163 Blue 3
9 PM Tue 79 79 W 10 5924 5100 0 Blue 2
10 PM Tue 78 78 W 9 5597 5100 0 Blue 1
11 PM Tue 78 78 W 9 5597 5100 0 Blue 1
12 Midnight Wed 77 77 W 8 5267 5100 0 Blue 0
1 AM Wed 76 76 W 8 3615 5100 0 Blue 0
2 AM Wed 76 76 SW 8 3615 5100 0 Blue 0
3 AM Wed 75 75 SW 8 3615 5100 0 Blue 0
4 AM Wed 73 73 SW 8 3615 5100 0 Blue 0
5 AM Wed 72 72 SW 9 3615 5100 0 Blue 0
6 AM Wed 72 72 SW 9 3615 5100 0 Blue 0
7 AM Wed 70 70 SW 9 3615 5100 0 Blue 0
8 AM Wed 70 70 SW 9 3615 5100 0 Blue 0
9 AM Wed 71 71 SW 9 3615 5100 0 Blue 0
10 AM Wed 70 71 SW 9 3615 5100 0 Blue 0
11 AM Wed 69 70 S 9 3615 5100 0 Blue 0
12 Noon Wed 71 72 S 9 3615 5100 0 Blue 0
1 PM Wed 71 72 S 9 3615 5100 0 Blue 0
2 PM Wed 72 73 S 8 3615 5100 0 Blue 0
3 PM Wed 72 73 S 8 3615 5100 0 Blue 0
4 PM Wed 73 73 S 8 3615 5100 0 Blue 0
5 PM Wed 73 73 SW 8 3615 5100 0 Blue 0
6 PM Wed 72 72 SW 7 3615 5100 0 Blue 0
7 PM Wed 71 71 SW 7 3615 5100 0 Blue 0
8 PM Wed 70 70 SW 6 3615 5100 0 Blue 0
9 PM Wed 69 69 SW 6 3615 5100 0 Blue 0
10 PM Wed 69 69 SW 6 3615 5100 0 Blue 0
11 PM Wed 70 70 SW 7 3615 5100 0 Blue 0
12 Midnight Thu 70 70 W 7 3615 5100 0 Blue 0
1 AM Thu 70 70 W 7 3615 5100 0 Blue 0
2 AM Thu 70 70 W 6 3615 5100 0 Blue 0
3 AM Thu 69 69 W 5 3615 5100 0 Blue 0
4 AM Thu 68 68 W 5 3615 5100 0 Blue 0
5 AM Thu 68 68 NW 3 3615 5100 0 Blue 0
6 AM Thu 67 67 NW 3 3615 5100 0 Blue 0
7 AM Thu 67 67 NW 3 3615 5100 0 Blue 0
8 AM Thu 67 67 NW 3 3615 5100 0 Blue 0
9 AM Thu 68 69 NW 3 3615 5100 0 Blue 0
10 AM Thu 70 73 NW 3 3615 5100 0 Blue 0
11 AM Thu 72 76 W 3 3615 5100 0 Blue 0
12 Noon Thu 74 78 W 3 5597 5100 0 Blue 1
1 PM Thu 76 80 W 5 6248 5263 163 Blue 3
2 PM Thu 78 82 SW 7 7727 5913 813 Blue 5
3 PM Thu 79 82 SW 8 7727 5913 813 Blue 5
4 PM Thu 80 81 SW 8 7001 5589 489 Blue 4
5 PM Thu 80 80 SW 8 6248 5263 163 Blue 3
6 PM Thu 79 79 SW 7 5924 5100 0 Blue 2
7 PM Thu 77 77 SW 7 5267 5100 0 Blue 0
8 PM Thu 75 75 W 7 3615 5100 0 Blue 0
9 PM Thu 74 74 W 7 3615 5100 0 Blue 0
10 PM Thu 73 73 SW 7 3615 5100 0 Blue 0
11 PM Thu 73 73 SW 6 3615 5100 0 Blue 0
12 Midnight Fri 73 73 SW 6 3615 5100 0 Blue 0
1 AM Fri 72 72 W 5 3615 5100 0 Blue 0
2 AM Fri 72 72 W 3 3615 5100 0 Blue 0
3 AM Fri 71 71 W 3 3615 5100 0 Blue 0
4 AM Fri 70 70 NW 3 3615 5100 0 Blue 0
5 AM Fri 69 69 N 5 3615 5100 0 Blue 0
6 AM Fri 69 69 NE 5 3615 5100 0 Blue 0
7 AM Fri 69 69 N 5 3615 5100 0 Blue 0
8 AM Fri 70 70 N 5 3615 5100 0 Blue 0
9 AM Fri 71 72 NW 5 3615 5100 0 Blue 0
10 AM Fri 73 76 W 3 3615 5100 0 Blue 0
11 AM Fri 75 79 SW 3 5924 5100 0 Blue 2
12 Noon Fri 77 81 SW 3 7001 5589 489 Blue 4
1 PM Fri 79 83 SW 3 8414 6234 1134 Blue 6
2 PM Fri 80 83 SW 5 8414 6234 1134 Blue 6
3 PM Fri 81 83 SW 6 8414 6234 1134 Blue 6
4 PM Fri 82 83 SW 6 8414 6234 1134 Blue 6
5 PM Fri 82 82 W 7 7727 5913 813 Blue 5
6 PM Fri 81 81 W 7 7001 5589 489 Blue 4
7 PM Fri 79 79 W 7 5924 5100 0 Blue 2
8 PM Fri 78 78 W 7 5597 5100 0 Blue 1
9 PM Fri 76 76 W 7 3615 5100 0 Blue 0
10 PM Fri 75 75 SW 6 3615 5100 0 Blue 0
11 PM Fri 75 75 SW 6 3615 5100 0 Blue 0
12 Midnight Sat 74 74 SW 6 3615 5100 0 Blue 0
1 AM Sat 73 73 W 6 3615 5100 0 Blue 0
2 AM Sat 72 72 W 6 3615 5100 0 Blue 0
3 AM Sat 71 71 NW 6 3615 5100 0 Blue 0
4 AM Sat 70 70 NW 6 3615 5100 0 Blue 0
5 AM Sat 69 69 N 6 3615 5100 0 Blue 0
6 AM Sat 69 69 N 6 3615 5100 0 Blue 0
7 AM Sat 70 70 NW 6 3615 5100 0 Blue 0
8 AM Sat 71 71 NW 5 3615 5100 0 Blue 0
9 AM Sat 72 73 W 5 3615 5100 0 Blue 0
10 AM Sat 74 77 SW 3 5267 5100 0 Blue 0
11 AM Sat 77 81 S 3 7001 5589 489 Blue 4
12 Noon Sat 79 83 S 3 8414 6234 1134 Blue 6
1 PM Sat 80 84 S 5 9051 6952 1852 Blue 7
2 PM Sat 82 86 S 5 11021 8341 3241 Blue 9
3 PM Sat 83 86 S 6 11021 8341 3241 Blue 9
4 PM Sat 84 85 SW 7 9592 7665 2565 Blue 8
5 PM Sat 84 84 SW 8 9051 6952 1852 Blue 7
6 PM Sat 83 83 SW 8 8414 6234 1134 Blue 6
7 PM Sat 81 81 SW 8 7001 5589 489 Blue 4
8 PM Sat 79 79 W 7 5924 5100 0 Blue 2
9 PM Sat 77 77 W 7 5267 5100 0 Blue 0
10 PM Sat 76 76 W 6 3615 5100 0 Blue 0
11 PM Sat 75 75 W 5 3615 5100 0 Blue 0
12 Midnight Sun 75 75 W 5 3615 5100 0 Blue 0
1 AM Sun 74 74 W 5 3615 5100 0 Blue 0
2 AM Sun 74 74 NW 5 3615 5100 0 Blue 0
3 AM Sun 73 73 NW 5 3615 5100 0 Blue 0
4 AM Sun 72 72 N 6 3615 5100 0 Blue 0
5 AM Sun 71 71 N 6 3615 5100 0 Blue 0
6 AM Sun 70 70 N 6 3615 5100 0 Blue 0
7 AM Sun 71 71 NE 6 3615 5100 0 Blue 0
8 AM Sun 72 72 E 6 3615 5100 0 Blue 0
9 AM Sun 73 75 E 5 3615 5100 0 Blue 0
10 AM Sun 75 78 SE 5 5597 5100 0 Blue 1
11 AM Sun 78 82 S 5 7727 5913 813 Blue 5
12 Noon Sun 80 85 S 5 9592 7665 2565 Blue 8
1 PM Sun 82 87 S 5 12198 8929 3829 White 10
2 PM Sun 83 87 SW 6 12198 8929 3829 White 10
3 PM Sun 84 87 SW 7 12198 8929 3829 White 10
4 PM Sun 84 86 SW 7 11021 8341 3241 Blue 9
5 PM Sun 84 84 SW 8 9051 6952 1852 Blue 7
6 PM Sun 83 83 SW 8 8414 6234 1134 Blue 6
7 PM Sun 81 81 SW 8 7001 5589 489 Blue 4
8 PM Sun 79 79 SW 8 5924 5100 0 Blue 2
9 PM Sun 78 78 W 7 5597 5100 0 Blue 1
10 PM Sun 76 76 W 7 3615 5100 0 Blue 0
11 PM Sun 76 76 W 6 3615 5100 0 Blue 0
12 Midnight Mon 75 75 W 6 3615 5100 0 Blue 0
1 AM Mon 75 75 W 6 3615 5100 0 Blue 0
2 AM Mon 74 74 SW 5 3615 5100 0 Blue 0
3 AM Mon 73 73 S 5 3615 5100 0 Blue 0
4 AM Mon 72 72 S 5 3615 5100 0 Blue 0
5 AM Mon 71 71 SE 5 3615 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