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

Station:

KTUS

Date/Time:

27 MAY 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 Sun 57 57 E 1 4823 5100 0 Blue 0
7 AM Sun 55 56 E 1 4823 5100 0 Blue 0
8 AM Sun 65 67 E 2 6715 5300 200 Blue 5
9 AM Sun 66 70 E 3 7603 6699 1599 Blue 8
10 AM Sun 68 74 E 5 8923 7918 2818 Blue 12
11 AM Sun 71 79 S 6 10155 9494 4394 Blue 17
12 Noon Sun 73 82 S 8 10817 10120 5020 Blue 20
1 PM Sun 74 83 S 9 11421 10337 5237 Blue 21
2 PM Sun 74 82 SW 10 10817 10120 5020 Blue 20
3 PM Sun 76 82 SW 12 10817 10120 5020 Blue 20
4 PM Sun 76 80 SW 13 10376 9712 4612 Blue 18
5 PM Sun 76 78 SW 12 9950 9190 4090 Blue 16
6 PM Sun 77 77 SW 12 9744 8883 3783 Blue 15
7 PM Sun 75 75 SW 10 9233 8260 3160 Blue 13
8 PM Sun 74 74 SW 9 8923 7918 2818 Blue 12
9 PM Sun 70 70 SW 8 7603 6699 1599 Blue 8
10 PM Sun 69 69 W 8 7251 6419 1319 Blue 7
11 PM Sun 68 68 W 7 6971 5869 769 Blue 6
12 Midnight Mon 67 67 W 6 6715 5300 200 Blue 5
1 AM Mon 66 66 W 6 6447 5106 6 Blue 4
2 AM Mon 65 65 W 5 5887 5100 0 Blue 3
3 AM Mon 64 64 W 5 5309 5100 0 Blue 2
4 AM Mon 63 63 NW 3 5108 5100 0 Blue 1
5 AM Mon 62 62 NW 3 4922 5100 0 Blue 0
6 AM Mon 61 61 NW 2 4823 5100 0 Blue 0
7 AM Mon 62 63 N 2 5108 5100 0 Blue 1
8 AM Mon 69 71 NE 3 7952 6953 1853 Blue 9
9 AM Mon 70 74 NE 3 8923 7918 2818 Blue 12
10 AM Mon 73 79 E 5 10155 9494 4394 Blue 17
11 AM Mon 76 84 S 5 12027 10556 5456 Blue 22
12 Noon Mon 78 87 SW 6 13709 11890 6790 Blue 25
1 PM Mon 79 88 SW 7 14232 12465 7365 Blue 26
2 PM Mon 80 88 SW 9 14232 12465 7365 Blue 26
3 PM Mon 81 87 SW 10 13709 11890 6790 Blue 25
4 PM Mon 82 86 SW 12 13169 11290 6190 Blue 24
5 PM Mon 82 84 SW 13 12027 10556 5456 Blue 22
6 PM Mon 82 82 SW 14 10817 10120 5020 Blue 20
7 PM Mon 80 80 SW 14 10376 9712 4612 Blue 18
8 PM Mon 78 78 SW 13 9950 9190 4090 Blue 16
9 PM Mon 76 76 SW 12 9538 8573 3473 Blue 14
10 PM Mon 75 75 W 10 9233 8260 3160 Blue 13
11 PM Mon 73 73 W 8 8611 7573 2473 Blue 11
12 Midnight Tue 72 72 W 7 8296 7224 2124 Blue 10
1 AM Tue 71 71 W 7 7952 6953 1853 Blue 9
2 AM Tue 70 70 NW 6 7603 6699 1599 Blue 8
3 AM Tue 69 69 N 6 7251 6419 1319 Blue 7
4 AM Tue 67 67 N 6 6715 5300 200 Blue 5
5 AM Tue 66 66 N 6 6447 5106 6 Blue 4
6 AM Tue 66 66 N 6 6447 5106 6 Blue 4
7 AM Tue 68 68 N 5 6971 5869 769 Blue 6
8 AM Tue 71 73 N 5 8611 7573 2473 Blue 11
9 AM Tue 75 78 N 3 9950 9190 4090 Blue 16
10 AM Tue 79 84 N 3 12027 10556 5456 Blue 22
11 AM Tue 81 87 W 5 13709 11890 6790 Blue 25
12 Noon Tue 84 91 SW 6 16233 14074 8974 Blue 29
1 PM Tue 85 91 SW 7 16233 14074 8974 Blue 29
2 PM Tue 86 92 SW 9 17454 14577 9477 Blue 30
3 PM Tue 86 90 SW 10 15233 13555 8455 Blue 28
4 PM Tue 87 90 SW 13 15233 13555 8455 Blue 28
5 PM Tue 87 88 SW 14 14232 12465 7365 Blue 26
6 PM Tue 86 86 SW 14 13169 11290 6190 Blue 24
7 PM Tue 85 85 SW 14 12609 10775 5675 Blue 23
8 PM Tue 82 82 SW 13 10817 10120 5020 Blue 20
9 PM Tue 80 80 SW 12 10376 9712 4612 Blue 18
10 PM Tue 77 77 SW 10 9744 8883 3783 Blue 15
11 PM Tue 76 76 SW 10 9538 8573 3473 Blue 14
12 Midnight Wed 75 75 SW 9 9233 8260 3160 Blue 13
1 AM Wed 74 74 W 8 8923 7918 2818 Blue 12
2 AM Wed 73 73 W 6 8611 7573 2473 Blue 11
3 AM Wed 72 72 W 5 8296 7224 2124 Blue 10
4 AM Wed 70 70 W 5 7603 6699 1599 Blue 8
5 AM Wed 68 68 SW 6 6971 5869 769 Blue 6
6 AM Wed 67 67 S 6 6715 5300 200 Blue 5
7 AM Wed 69 69 S 6 7251 6419 1319 Blue 7
8 AM Wed 72 74 S 7 8923 7918 2818 Blue 12
9 AM Wed 76 80 S 7 10376 9712 4612 Blue 18
10 AM Wed 79 85 S 8 12609 10775 5675 Blue 23
11 AM Wed 81 89 S 8 14740 13020 7920 Blue 27
12 Noon Wed 82 91 S 9 16233 14074 8974 Blue 29
1 PM Wed 84 92 S 10 17454 14577 9477 Blue 30
2 PM Wed 85 92 S 10 17454 14577 9477 Blue 30
3 PM Wed 85 91 S 12 16233 14074 8974 Blue 29
4 PM Wed 86 90 SW 13 15233 13555 8455 Blue 28
5 PM Wed 86 88 SW 13 14232 12465 7365 Blue 26
6 PM Wed 85 85 SW 13 12609 10775 5675 Blue 23
7 PM Wed 84 84 SW 13 12027 10556 5456 Blue 22
8 PM Wed 81 81 SW 12 10597 9916 4816 Blue 19
9 PM Wed 79 79 SW 10 10155 9494 4394 Blue 17
10 PM Wed 77 77 SW 9 9744 8883 3783 Blue 15
11 PM Wed 75 75 SW 9 9233 8260 3160 Blue 13
12 Midnight Thu 73 73 SW 8 8611 7573 2473 Blue 11
1 AM Thu 72 72 SW 7 8296 7224 2124 Blue 10
2 AM Thu 70 70 S 7 7603 6699 1599 Blue 8
3 AM Thu 69 69 S 7 7251 6419 1319 Blue 7
4 AM Thu 66 66 S 7 6447 5106 6 Blue 4
5 AM Thu 64 64 S 7 5309 5100 0 Blue 2
6 AM Thu 64 64 SE 8 5309 5100 0 Blue 2
7 AM Thu 66 66 SE 8 6447 5106 6 Blue 4
8 AM Thu 69 71 S 9 7952 6953 1853 Blue 9
9 AM Thu 72 76 S 10 9538 8573 3473 Blue 14
10 AM Thu 76 81 S 10 10597 9916 4816 Blue 19
11 AM Thu 78 85 S 12 12609 10775 5675 Blue 23
12 Noon Thu 80 87 S 13 13709 11890 6790 Blue 25
1 PM Thu 81 88 S 14 14232 12465 7365 Blue 26
2 PM Thu 82 88 S 15 14232 12465 7365 Blue 26
3 PM Thu 83 88 S 15 14232 12465 7365 Blue 26
4 PM Thu 84 87 S 16 13709 11890 6790 Blue 25
5 PM Thu 84 85 SW 16 12609 10775 5675 Blue 23
6 PM Thu 84 84 SW 16 12027 10556 5456 Blue 22
7 PM Thu 82 82 SW 16 10817 10120 5020 Blue 20
8 PM Thu 79 79 SW 15 10155 9494 4394 Blue 17
9 PM Thu 77 77 SW 14 9744 8883 3783 Blue 15
10 PM Thu 74 74 SW 12 8923 7918 2818 Blue 12
11 PM Thu 72 72 SW 10 8296 7224 2124 Blue 10
12 Midnight Fri 71 71 SW 9 7952 6953 1853 Blue 9
1 AM Fri 69 69 SW 8 7251 6419 1319 Blue 7
2 AM Fri 68 68 S 8 6971 5869 769 Blue 6
3 AM Fri 66 66 S 7 6447 5106 6 Blue 4
4 AM Fri 64 64 S 7 5309 5100 0 Blue 2
5 AM Fri 62 62 S 6 4922 5100 0 Blue 0
6 AM Fri 62 62 SE 6 4922 5100 0 Blue 0
7 AM Fri 64 64 S 7 5309 5100 0 Blue 2
8 AM Fri 67 69 S 7 7251 6419 1319 Blue 7
9 AM Fri 71 75 S 8 9233 8260 3160 Blue 13
10 AM Fri 75 81 S 9 10597 9916 4816 Blue 19
11 AM Fri 77 85 S 9 12609 10775 5675 Blue 23
12 Noon Fri 80 89 S 10 14740 13020 7920 Blue 27
1 PM Fri 81 90 S 12 15233 13555 8455 Blue 28
2 PM Fri 83 91 S 12 16233 14074 8974 Blue 29
3 PM Fri 84 90 SW 13 15233 13555 8455 Blue 28
4 PM Fri 84 88 SW 13 14232 12465 7365 Blue 26
5 PM Fri 84 86 SW 13 13169 11290 6190 Blue 24
6 PM Fri 83 83 SW 13 11421 10337 5237 Blue 21
7 PM Fri 81 81 SW 12 10597 9916 4816 Blue 19
8 PM Fri 78 78 W 10 9950 9190 4090 Blue 16
9 PM Fri 75 75 W 9 9233 8260 3160 Blue 13
10 PM Fri 73 73 NW 8 8611 7573 2473 Blue 11
11 PM Fri 71 71 NW 7 7952 6953 1853 Blue 9
12 Midnight Sat 69 69 N 6 7251 6419 1319 Blue 7
1 AM Sat 68 68 N 6 6971 5869 769 Blue 6
2 AM Sat 67 67 N 6 6715 5300 200 Blue 5
3 AM Sat 66 66 N 6 6447 5106 6 Blue 4
4 AM Sat 64 64 NE 6 5309 5100 0 Blue 2
5 AM Sat 63 63 NE 6 5108 5100 0 Blue 1

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