Detailed Predictions for: The Y
Launch Altitude (f): 4900
LZ Altitude (f): 3150
Sounding

Station:

KTUS

Date/Time:

17 JAN 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)
5 AM Wed 47 47 NE 6 3316 4900 0 Blue 0
6 AM Wed 46 46 NE 7 3110 4900 0 Blue 0
7 AM Wed 46 46 NE 7 3110 4900 0 Blue 0
8 AM Wed 47 47 NE 8 3316 4900 0 Blue 0
9 AM Wed 51 51 NE 7 4137 4900 0 Blue 0
10 AM Wed 56 57 N 6 5317 4900 0 Blue 1
11 AM Wed 61 63 N 5 6370 5835 935 Blue 7
12 Noon Wed 64 66 NW 5 6893 6357 1457 Blue 10
1 PM Wed 65 68 NW 5 7908 6704 1804 Blue 12
2 PM Wed 66 68 NW 5 7908 6704 1804 Blue 12
3 PM Wed 66 67 NW 6 7339 6531 1631 Blue 11
4 PM Wed 66 66 W 6 6893 6357 1457 Blue 10
5 PM Wed 65 65 W 6 6719 6183 1283 Blue 9
6 PM Wed 62 62 NW 7 6195 5660 760 Blue 6
7 PM Wed 59 59 NW 8 5669 5135 235 Blue 3
8 PM Wed 56 56 N 10 5141 4900 0 Blue 0
9 PM Wed 55 55 N 10 4950 4900 0 Blue 0
10 PM Wed 53 53 NE 10 4544 4900 0 Blue 0
11 PM Wed 53 53 NE 10 4544 4900 0 Blue 0
12 Midnight Thu 52 52 NE 10 4341 4900 0 Blue 0
1 AM Thu 52 52 NE 10 4341 4900 0 Blue 0
2 AM Thu 52 52 NE 10 4341 4900 0 Blue 0
3 AM Thu 51 51 NE 9 4137 4900 0 Blue 0
4 AM Thu 50 50 NE 8 3932 4900 0 Blue 0
5 AM Thu 49 49 NE 8 3727 4900 0 Blue 0
6 AM Thu 48 48 E 8 3522 4900 0 Blue 0
7 AM Thu 48 48 E 8 3522 4900 0 Blue 0
8 AM Thu 49 49 E 8 3727 4900 0 Blue 0
9 AM Thu 53 53 E 6 4544 4900 0 Blue 0
10 AM Thu 58 59 SE 3 5669 5135 235 Blue 3
11 AM Thu 62 63 SE 3 6370 5835 935 Blue 7
12 Noon Thu 65 67 S 3 7339 6531 1631 Blue 11
1 PM Thu 66 68 SW 5 7908 6704 1804 Blue 12
2 PM Thu 67 69 SW 6 9259 6877 1977 Blue 13
3 PM Thu 67 68 SW 6 7908 6704 1804 Blue 12
4 PM Thu 67 67 SW 6 7339 6531 1631 Blue 11
5 PM Thu 66 66 SW 6 6893 6357 1457 Blue 10
6 PM Thu 63 63 SW 5 6370 5835 935 Blue 7
7 PM Thu 60 60 S 3 5844 5311 411 Blue 4
8 PM Thu 57 57 S 5 5317 4900 0 Blue 1
9 PM Thu 55 55 S 5 4950 4900 0 Blue 0
10 PM Thu 54 54 SE 5 4747 4900 0 Blue 0
11 PM Thu 54 54 SE 6 4747 4900 0 Blue 0
12 Midnight Fri 53 53 SE 6 4544 4900 0 Blue 0
1 AM Fri 53 53 SE 6 4544 4900 0 Blue 0
2 AM Fri 53 53 SE 7 4544 4900 0 Blue 0
3 AM Fri 52 52 SE 7 4341 4900 0 Blue 0
4 AM Fri 51 51 SE 7 4137 4900 0 Blue 0
5 AM Fri 50 50 SE 8 3932 4900 0 Blue 0
6 AM Fri 49 49 SE 8 3727 4900 0 Blue 0
7 AM Fri 49 49 SE 8 3727 4900 0 Blue 0
8 AM Fri 50 50 SE 9 3932 4900 0 Blue 0
9 AM Fri 55 55 SE 10 4950 4900 0 Blue 0
10 AM Fri 59 60 SE 12 5844 5311 411 Blue 4
11 AM Fri 62 63 SE 14 6370 5835 935 Blue 7
12 Noon Fri 64 65 S 14 6719 6183 1283 Blue 9
1 PM Fri 64 65 S 14 6719 6183 1283 Blue 9
2 PM Fri 64 65 S 15 6719 6183 1283 Blue 9
3 PM Fri 64 65 S 15 6719 6183 1283 Blue 9
4 PM Fri 63 63 S 16 6370 5835 935 Blue 7
5 PM Fri 61 61 S 16 6020 5486 586 Blue 5
6 PM Fri 59 59 S 15 5669 5135 235 Blue 3
7 PM Fri 57 57 S 15 5317 4900 0 Blue 1
8 PM Fri 55 55 S 14 4950 4900 0 Blue 0
9 PM Fri 54 54 S 13 4747 4900 0 Blue 0
10 PM Fri 54 54 S 13 4747 4900 0 Blue 0
11 PM Fri 54 54 S 12 4747 4900 0 Blue 0
12 Midnight Sat 54 54 SW 12 4747 4900 0 Blue 0
1 AM Sat 53 53 SW 10 4544 4900 0 Blue 0
2 AM Sat 52 52 W 10 4341 4900 0 Blue 0
3 AM Sat 50 50 W 10 3932 4900 0 Blue 0
4 AM Sat 48 48 W 10 3522 4900 0 Blue 0
5 AM Sat 46 46 W 12 3110 4900 0 Blue 0
6 AM Sat 45 45 W 12 2933 4900 0 Blue 0
7 AM Sat 44 44 W 12 2933 4900 0 Blue 0
8 AM Sat 44 44 W 10 2933 4900 0 Blue 0
9 AM Sat 44 44 W 9 2933 4900 0 Blue 0
10 AM Sat 44 44 W 9 2933 4900 0 Blue 0
11 AM Sat 45 46 W 9 3110 4900 0 Blue 0
12 Noon Sat 46 47 W 10 3316 4900 0 Blue 0
1 PM Sat 47 48 W 13 3522 4900 0 Blue 0
2 PM Sat 47 48 W 15 3522 4900 0 Blue 0
3 PM Sat 47 48 W 17 3522 4900 0 Blue 0
4 PM Sat 46 46 W 20 3110 4900 0 Blue 0
5 PM Sat 46 46 W 22 3110 4900 0 Blue 0
6 PM Sat 46 46 W 20 3110 4900 0 Blue 0
7 PM Sat 45 45 W 18 2933 4900 0 Blue 0
8 PM Sat 45 45 W 17 2933 4900 0 Blue 0
9 PM Sat 45 45 W 16 2933 4900 0 Blue 0
10 PM Sat 44 44 W 14 2933 4900 0 Blue 0
11 PM Sat 44 44 NW 13 2933 4900 0 Blue 0
12 Midnight Sun 43 43 NW 12 2933 4900 0 Blue 0
1 AM Sun 42 42 NW 12 2933 4900 0 Blue 0
2 AM Sun 41 41 NW 12 2933 4900 0 Blue 0
3 AM Sun 40 40 NW 12 2933 4900 0 Blue 0
4 AM Sun 39 39 NW 12 2933 4900 0 Blue 0
5 AM Sun 37 37 NW 13 2933 4900 0 Blue 0
6 AM Sun 36 36 NW 13 2933 4900 0 Blue 0
7 AM Sun 36 36 NW 12 2933 4900 0 Blue 0
8 AM Sun 37 37 N 10 2933 4900 0 Blue 0
9 AM Sun 40 40 N 10 2933 4900 0 Blue 0
10 AM Sun 43 44 N 10 2933 4900 0 Blue 0
11 AM Sun 47 49 N 9 3727 4900 0 Blue 0
12 Noon Sun 49 51 N 9 4137 4900 0 Blue 0
1 PM Sun 51 54 NW 8 4747 4900 0 Blue 0
2 PM Sun 52 54 NW 9 4747 4900 0 Blue 0
3 PM Sun 53 54 NW 9 4747 4900 0 Blue 0
4 PM Sun 53 53 NW 9 4544 4900 0 Blue 0
5 PM Sun 52 52 NW 9 4341 4900 0 Blue 0
6 PM Sun 50 50 NW 8 3932 4900 0 Blue 0
7 PM Sun 47 47 NW 8 3316 4900 0 Blue 0
8 PM Sun 45 45 NW 7 2933 4900 0 Blue 0
9 PM Sun 44 44 NW 6 2933 4900 0 Blue 0
10 PM Sun 43 43 N 6 2933 4900 0 Blue 0
11 PM Sun 43 43 N 6 2933 4900 0 Blue 0
12 Midnight Mon 42 42 N 5 2933 4900 0 Blue 0
1 AM Mon 41 41 NE 6 2933 4900 0 Blue 0
2 AM Mon 41 41 NE 6 2933 4900 0 Blue 0
3 AM Mon 40 40 NE 6 2933 4900 0 Blue 0
4 AM Mon 40 40 NE 6 2933 4900 0 Blue 0
5 AM Mon 40 40 NE 6 2933 4900 0 Blue 0
6 AM Mon 39 39 NE 6 2933 4900 0 Blue 0
7 AM Mon 39 39 E 6 2933 4900 0 Blue 0
8 AM Mon 41 41 E 6 2933 4900 0 Blue 0
9 AM Mon 44 44 SE 6 2933 4900 0 Blue 0
10 AM Mon 49 50 SE 6 3932 4900 0 Blue 0
11 AM Mon 53 54 S 6 4747 4900 0 Blue 0
12 Noon Mon 56 58 SW 6 5493 4945 45 Blue 2
1 PM Mon 57 59 SW 6 5669 5135 235 Blue 3
2 PM Mon 58 59 W 6 5669 5135 235 Blue 3
3 PM Mon 58 59 W 6 5669 5135 235 Blue 3
4 PM Mon 58 58 W 6 5493 4945 45 Blue 2
5 PM Mon 57 57 W 6 5317 4900 0 Blue 1
6 PM Mon 54 54 W 7 4747 4900 0 Blue 0
7 PM Mon 52 52 W 7 4341 4900 0 Blue 0
8 PM Mon 50 50 NW 7 3932 4900 0 Blue 0
9 PM Mon 48 48 NW 7 3522 4900 0 Blue 0
10 PM Mon 47 47 NW 7 3316 4900 0 Blue 0
11 PM Mon 46 46 N 7 3110 4900 0 Blue 0
12 Midnight Tue 46 46 N 7 3110 4900 0 Blue 0
1 AM Tue 45 45 N 7 2933 4900 0 Blue 0
2 AM Tue 45 45 N 7 2933 4900 0 Blue 0
3 AM Tue 44 44 N 7 2933 4900 0 Blue 0
4 AM Tue 43 43 N 7 2933 4900 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