Detailed Predictions for: BJ
Launch Altitude (f): 582
LZ Altitude (f): 180
Sounding

Station:

KOTX

Date/Time:

18 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)
4 AM Thu 43 43 S 16 2706 2581 1999 Blue 8
5 AM Thu 42 42 S 16 2664 2539 1957 Blue 7
6 AM Thu 42 42 S 16 2664 2539 1957 Blue 7
7 AM Thu 41 41 S 18 2622 2498 1916 Blue 6
8 AM Thu 42 42 S 18 2664 2539 1957 Blue 7
9 AM Thu 42 42 S 18 2664 2539 1957 Blue 7
10 AM Thu 43 43 S 21 2706 2581 1999 Blue 8
11 AM Thu 43 43 S 21 2706 2581 1999 Blue 8
12 Noon Thu 43 43 S 21 2706 2581 1999 Blue 8
1 PM Thu 43 43 S 18 2706 2581 1999 Blue 8
2 PM Thu 43 43 S 18 2706 2581 1999 Blue 8
3 PM Thu 43 43 S 18 2706 2581 1999 Blue 8
4 PM Thu 42 42 S 18 2664 2539 1957 Blue 7
5 PM Thu 42 42 S 18 2664 2539 1957 Blue 7
6 PM Thu 41 41 S 18 2622 2498 1916 Blue 6
7 PM Thu 41 41 S 18 2622 2498 1916 Blue 6
8 PM Thu 39 39 S 18 2539 2415 1833 Blue 4
9 PM Thu 40 40 S 18 2581 2456 1874 Blue 5
10 PM Thu 40 40 S 17 2581 2456 1874 Blue 5
11 PM Thu 39 39 S 17 2539 2415 1833 Blue 4
12 Midnight Fri 39 39 S 17 2539 2415 1833 Blue 4
1 AM Fri 39 39 S 14 2539 2415 1833 Blue 4
2 AM Fri 38 38 S 14 2498 2398 1816 Blue 3
3 AM Fri 39 39 S 14 2539 2415 1833 Blue 4
4 AM Fri 40 40 S 13 2581 2456 1874 Blue 5
5 AM Fri 39 39 S 13 2539 2415 1833 Blue 4
6 AM Fri 39 39 S 13 2539 2415 1833 Blue 4
7 AM Fri 38 38 S 12 2498 2398 1816 Blue 3
8 AM Fri 39 39 S 12 2539 2415 1833 Blue 4
9 AM Fri 40 40 S 12 2581 2456 1874 Blue 5
10 AM Fri 40 40 S 13 2581 2456 1874 Blue 5
11 AM Fri 40 40 S 13 2581 2456 1874 Blue 5
12 Noon Fri 41 41 S 13 2622 2498 1916 Blue 6
1 PM Fri 41 41 S 15 2622 2498 1916 Blue 6
2 PM Fri 41 41 S 15 2622 2498 1916 Blue 6
3 PM Fri 41 41 S 15 2622 2498 1916 Blue 6
4 PM Fri 40 40 S 13 2581 2456 1874 Blue 5
5 PM Fri 40 40 S 13 2581 2456 1874 Blue 5
6 PM Fri 39 39 S 13 2539 2415 1833 Blue 4
7 PM Fri 39 39 S 12 2539 2415 1833 Blue 4
8 PM Fri 37 37 S 12 2456 2398 1816 Blue 2
9 PM Fri 38 38 S 12 2498 2398 1816 Blue 3
10 PM Fri 38 38 S 12 2498 2398 1816 Blue 3
11 PM Fri 37 37 S 12 2456 2398 1816 Blue 2
12 Midnight Sat 37 37 S 12 2456 2398 1816 Blue 2
1 AM Sat 37 37 S 13 2456 2398 1816 Blue 2
2 AM Sat 36 36 S 13 2415 2398 1816 Blue 1
3 AM Sat 37 37 S 13 2456 2398 1816 Blue 2
4 AM Sat 38 38 S 14 2498 2398 1816 Blue 3
5 AM Sat 37 37 S 14 2456 2398 1816 Blue 2
6 AM Sat 37 37 S 14 2456 2398 1816 Blue 2
7 AM Sat 36 36 S 10 2415 2398 1816 Blue 1
8 AM Sat 38 38 S 10 2498 2398 1816 Blue 3
9 AM Sat 38 38 S 10 2498 2398 1816 Blue 3
10 AM Sat 39 39 SW 9 2539 2415 1833 Blue 4
11 AM Sat 39 39 SW 9 2539 2415 1833 Blue 4
12 Noon Sat 40 40 SW 9 2581 2456 1874 Blue 5
1 PM Sat 40 40 S 10 2581 2456 1874 Blue 5
2 PM Sat 40 40 S 10 2581 2456 1874 Blue 5
3 PM Sat 40 40 S 10 2581 2456 1874 Blue 5
4 PM Sat 40 40 S 10 2581 2456 1874 Blue 5
5 PM Sat 39 39 S 10 2539 2415 1833 Blue 4
6 PM Sat 39 39 S 10 2539 2415 1833 Blue 4
7 PM Sat 39 39 S 10 2539 2415 1833 Blue 4
8 PM Sat 38 38 S 10 2498 2398 1816 Blue 3
9 PM Sat 38 38 S 10 2498 2398 1816 Blue 3
10 PM Sat 38 38 S 17 2498 2398 1816 Blue 3
11 PM Sat 37 37 S 17 2456 2398 1816 Blue 2
12 Midnight Sun 37 37 S 17 2456 2398 1816 Blue 2
1 AM Sun 37 37 S 17 2456 2398 1816 Blue 2
2 AM Sun 37 37 S 17 2456 2398 1816 Blue 2
3 AM Sun 38 38 S 17 2498 2398 1816 Blue 3
4 AM Sun 38 38 S 21 2498 2398 1816 Blue 3
5 AM Sun 38 38 S 21 2498 2398 1816 Blue 3
6 AM Sun 38 38 S 21 2498 2398 1816 Blue 3
7 AM Sun 37 37 S 21 2456 2398 1816 Blue 2
8 AM Sun 38 38 S 21 2498 2398 1816 Blue 3
9 AM Sun 39 39 S 21 2539 2415 1833 Blue 4
10 AM Sun 39 39 S 23 2539 2415 1833 Blue 4
11 AM Sun 39 39 S 23 2539 2415 1833 Blue 4
12 Noon Sun 40 40 S 23 2581 2456 1874 Blue 5
1 PM Sun 40 40 S 23 2581 2456 1874 Blue 5
2 PM Sun 40 40 S 23 2581 2456 1874 Blue 5
3 PM Sun 40 40 S 23 2581 2456 1874 Blue 5
4 PM Sun 39 39 S 9 2539 2415 1833 Blue 4
5 PM Sun 39 39 S 9 2539 2415 1833 Blue 4
6 PM Sun 38 38 S 9 2498 2398 1816 Blue 3
7 PM Sun 38 38 S 9 2498 2398 1816 Blue 3
8 PM Sun 36 36 S 9 2415 2398 1816 Blue 1
9 PM Sun 37 37 S 9 2456 2398 1816 Blue 2
10 PM Sun 37 37 S 8 2456 2398 1816 Blue 2
11 PM Sun 36 36 S 8 2415 2398 1816 Blue 1
12 Midnight Mon 36 36 S 8 2415 2398 1816 Blue 1
1 AM Mon 36 36 S 8 2415 2398 1816 Blue 1
2 AM Mon 35 35 S 8 0 2398 1816 Blue 0
3 AM Mon 36 36 S 8 2415 2398 1816 Blue 1
4 AM Mon 37 37 S 12 2456 2398 1816 Blue 2
5 AM Mon 36 36 S 12 2415 2398 1816 Blue 1
6 AM Mon 36 36 S 12 2415 2398 1816 Blue 1
7 AM Mon 35 35 S 12 0 2398 1816 Blue 0
8 AM Mon 37 37 S 12 2456 2398 1816 Blue 2
9 AM Mon 37 37 S 12 2456 2398 1816 Blue 2
10 AM Mon 38 38 SW 9 2498 2398 1816 Blue 3
11 AM Mon 38 38 SW 9 2498 2398 1816 Blue 3
12 Noon Mon 39 39 SW 9 2539 2415 1833 Blue 4
1 PM Mon 39 39 SW 9 2539 2415 1833 Blue 4
2 PM Mon 39 39 SW 9 2539 2415 1833 Blue 4
3 PM Mon 39 39 SW 9 2539 2415 1833 Blue 4
4 PM Mon 38 38 SW 10 2498 2398 1816 Blue 3
5 PM Mon 37 37 SW 10 2456 2398 1816 Blue 2
6 PM Mon 37 37 SW 10 2456 2398 1816 Blue 2
7 PM Mon 36 36 SW 10 2415 2398 1816 Blue 1
8 PM Mon 34 34 SW 10 0 2398 1816 Blue 0
9 PM Mon 36 36 SW 10 2415 2398 1816 Blue 1
10 PM Mon 35 35 SE 3 0 2398 1816 Blue 0
11 PM Mon 34 34 SE 3 0 2398 1816 Blue 0
12 Midnight Tue 34 34 SE 3 0 2398 1816 Blue 0
1 AM Tue 34 34 SE 3 0 2398 1816 Blue 0
2 AM Tue 33 33 SE 3 0 2398 1816 Blue 0
3 AM Tue 35 35 SE 3 0 2398 1816 Blue 0
4 AM Tue 35 35 E 6 0 2398 1816 Blue 0
5 AM Tue 34 34 E 6 0 2398 1816 Blue 0
6 AM Tue 35 35 E 6 0 2398 1816 Blue 0
7 AM Tue 33 33 E 6 0 2398 1816 Blue 0
8 AM Tue 35 35 E 6 0 2398 1816 Blue 0
9 AM Tue 36 36 E 6 2415 2398 1816 Blue 1
10 AM Tue 36 36 E 7 2415 2398 1816 Blue 1
11 AM Tue 37 37 E 7 2456 2398 1816 Blue 2
12 Noon Tue 37 37 E 7 2456 2398 1816 Blue 2
1 PM Tue 38 38 E 7 2498 2398 1816 Blue 3
2 PM Tue 38 38 E 7 2498 2398 1816 Blue 3
3 PM Tue 38 38 E 7 2498 2398 1816 Blue 3
4 PM Tue 37 37 SE 9 2456 2398 1816 Blue 2
5 PM Tue 37 37 SE 9 2456 2398 1816 Blue 2
6 PM Tue 36 36 SE 9 2415 2398 1816 Blue 1
7 PM Tue 36 36 SE 9 2415 2398 1816 Blue 1
8 PM Tue 34 34 SE 9 0 2398 1816 Blue 0
9 PM Tue 35 35 SE 9 0 2398 1816 Blue 0
10 PM Tue 35 35 SE 15 0 2398 1816 Blue 0
11 PM Tue 34 34 SE 15 0 2398 1816 Blue 0
12 Midnight Wed 34 34 SE 15 0 2398 1816 Blue 0
1 AM Wed 34 34 SE 15 0 2398 1816 Blue 0
2 AM Wed 33 33 SE 15 0 2398 1816 Blue 0
3 AM Wed 34 34 SE 15 0 2398 1816 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