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

Station:

KOTX

Date/Time:

18 OCT 2019

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 Fri 42 42 S 12 1266 1266 684 White 0
6 AM Fri 43 43 S 12 1266 1266 684 White 0
7 AM Fri 42 42 S 12 1266 1266 684 White 0
8 AM Fri 43 43 S 10 1266 1266 684 White 0
9 AM Fri 44 44 S 10 1266 1266 684 White 0
10 AM Fri 45 45 S 10 1266 1266 684 White 0
11 AM Fri 45 45 S 13 1266 1266 684 White 0
12 Noon Fri 48 48 S 13 1266 1266 684 White 0
1 PM Fri 49 49 S 13 1275 1275 693 White 0
2 PM Fri 48 48 S 14 1266 1266 684 White 0
3 PM Fri 47 47 S 14 1266 1266 684 White 0
4 PM Fri 47 47 S 14 1266 1266 684 White 0
5 PM Fri 47 47 S 9 1266 1266 684 White 0
6 PM Fri 47 47 S 9 1266 1266 684 White 0
7 PM Fri 44 44 S 9 1266 1266 684 White 0
8 PM Fri 43 43 S 6 1266 1266 684 White 0
9 PM Fri 44 44 S 6 1266 1266 684 White 0
10 PM Fri 42 42 S 6 1266 1266 684 White 0
11 PM Fri 42 42 SE 12 1266 1266 684 White 0
12 Midnight Sat 43 43 SE 12 1266 1266 684 White 0
1 AM Sat 41 41 SE 12 1266 1266 684 White 0
2 AM Sat 41 41 S 7 1266 1266 684 White 0
3 AM Sat 42 42 S 7 1266 1266 684 White 0
4 AM Sat 41 41 S 7 1266 1266 684 White 0
5 AM Sat 41 41 S 9 1266 1266 684 White 0
6 AM Sat 42 42 S 9 1266 1266 684 White 0
7 AM Sat 41 41 S 9 1266 1266 684 White 0
8 AM Sat 42 42 SE 9 1266 1266 684 White 0
9 AM Sat 43 43 SE 9 1266 1266 684 White 0
10 AM Sat 44 44 SE 9 1266 1266 684 White 0
11 AM Sat 44 44 S 10 1266 1266 684 White 0
12 Noon Sat 47 47 S 10 1266 1266 684 White 0
1 PM Sat 48 48 S 10 1266 1266 684 White 0
2 PM Sat 47 47 SW 7 1266 1266 684 White 0
3 PM Sat 46 46 SW 7 1266 1266 684 White 0
4 PM Sat 46 46 SW 7 1266 1266 684 White 0
5 PM Sat 46 46 S 7 1266 1266 684 White 0
6 PM Sat 46 46 S 7 1266 1266 684 White 0
7 PM Sat 43 43 S 7 1266 1266 684 White 0
8 PM Sat 42 42 SW 7 1266 1266 684 White 0
9 PM Sat 43 43 SW 7 1266 1266 684 White 0
10 PM Sat 41 41 SW 7 1266 1266 684 White 0
11 PM Sat 41 41 S 6 1266 1266 684 White 0
12 Midnight Sun 42 42 S 6 1266 1266 684 White 0
1 AM Sun 40 40 S 6 0 582 0 Blue 0
2 AM Sun 40 40 S 5 0 582 0 Blue 0
3 AM Sun 41 41 S 5 1266 1266 684 White 0
4 AM Sun 40 40 S 5 0 582 0 Blue 0
5 AM Sun 40 40 SE 3 0 582 0 Blue 0
6 AM Sun 42 42 SE 3 1266 1266 684 White 0
7 AM Sun 41 41 SE 3 1266 1266 684 White 0
8 AM Sun 41 41 SE 6 1266 1266 684 White 0
9 AM Sun 43 43 SE 6 1266 1266 684 White 0
10 AM Sun 43 43 SE 6 1266 1266 684 White 0
11 AM Sun 44 44 S 6 1266 1266 684 White 0
12 Noon Sun 48 48 S 6 1266 1266 684 White 0
1 PM Sun 49 49 S 6 1275 1275 693 White 0
2 PM Sun 48 48 SE 7 1266 1266 684 White 0
3 PM Sun 48 48 SE 7 1266 1266 684 White 0
4 PM Sun 47 47 SE 7 1266 1266 684 White 0
5 PM Sun 47 47 SE 7 1266 1266 684 White 0
6 PM Sun 47 47 SE 7 1266 1266 684 White 0
7 PM Sun 45 45 SE 7 1266 1266 684 White 0
8 PM Sun 44 44 SE 7 1266 1266 684 White 0
9 PM Sun 44 44 SE 7 1266 1266 684 White 0
10 PM Sun 43 43 SE 7 1266 1266 684 White 0
11 PM Sun 43 43 S 5 1266 1266 684 White 0
12 Midnight Mon 43 43 S 5 1266 1266 684 White 0
1 AM Mon 42 42 S 5 1266 1266 684 White 0
2 AM Mon 42 42 S 5 1266 1266 684 White 0
3 AM Mon 43 43 S 5 1266 1266 684 White 0
4 AM Mon 42 42 S 5 1266 1266 684 White 0
5 AM Mon 42 42 S 6 1266 1266 684 White 0
6 AM Mon 44 44 S 6 1266 1266 684 White 0
7 AM Mon 43 43 S 6 1266 1266 684 White 0
8 AM Mon 43 43 S 6 1266 1266 684 White 0
9 AM Mon 45 45 S 6 1266 1266 684 White 0
10 AM Mon 46 46 S 6 1266 1266 684 White 0
11 AM Mon 47 47 S 8 1266 1266 684 White 0
12 Noon Mon 51 51 S 8 1710 1710 1128 White 0
1 PM Mon 52 52 S 8 1926 1926 1344 White 0
2 PM Mon 51 51 S 8 1710 1710 1128 White 0
3 PM Mon 51 51 S 8 1710 1710 1128 White 0
4 PM Mon 50 50 S 8 1493 1493 911 White 0
5 PM Mon 50 50 SE 9 1493 1493 911 White 0
6 PM Mon 50 50 SE 9 1493 1493 911 White 0
7 PM Mon 48 48 SE 9 1266 1266 684 White 0
8 PM Mon 47 47 SE 9 1266 1266 684 White 0
9 PM Mon 47 47 SE 9 1266 1266 684 White 0
10 PM Mon 46 46 SE 9 1266 1266 684 White 0
11 PM Mon 46 46 S 8 1266 1266 684 White 0
12 Midnight Tue 46 46 S 8 1266 1266 684 White 0
1 AM Tue 45 45 S 8 1266 1266 684 White 0
2 AM Tue 45 45 S 8 1266 1266 684 White 0
3 AM Tue 46 46 S 8 1266 1266 684 White 0
4 AM Tue 45 45 S 8 1266 1266 684 White 0
5 AM Tue 45 45 S 8 1266 1266 684 White 0
6 AM Tue 46 46 S 8 1266 1266 684 White 0
7 AM Tue 45 45 S 8 1266 1266 684 White 0
8 AM Tue 46 46 S 8 1266 1266 684 White 0
9 AM Tue 47 47 S 8 1266 1266 684 White 0
10 AM Tue 48 48 S 8 1266 1266 684 White 0
11 AM Tue 49 49 SW 8 1275 1275 693 White 0
12 Noon Tue 52 52 SW 8 1926 1926 1344 White 0
1 PM Tue 53 53 SW 8 2143 2143 1561 White 0
2 PM Tue 51 51 SW 8 1710 1710 1128 White 0
3 PM Tue 50 50 SW 8 1493 1493 911 White 0
4 PM Tue 50 50 SW 8 1493 1493 911 White 0
5 PM Tue 49 49 S 8 1275 1275 693 White 0
6 PM Tue 49 49 S 8 1275 1275 693 White 0
7 PM Tue 46 46 S 8 1266 1266 684 White 0
8 PM Tue 45 45 S 8 1266 1266 684 White 0
9 PM Tue 45 45 S 8 1266 1266 684 White 0
10 PM Tue 43 43 S 8 1266 1266 684 White 0
11 PM Tue 43 43 S 6 1266 1266 684 White 0
12 Midnight Wed 44 44 S 6 1266 1266 684 White 0
1 AM Wed 42 42 S 6 1266 1266 684 White 0
2 AM Wed 41 41 S 6 1266 1266 684 White 0
3 AM Wed 43 43 S 6 1266 1266 684 White 0
4 AM Wed 41 41 S 6 1266 1266 684 White 0
5 AM Wed 41 41 S 3 1266 1266 684 White 0
6 AM Wed 43 43 S 3 1266 1266 684 White 0
7 AM Wed 42 42 S 3 1266 1266 684 White 0
8 AM Wed 42 42 S 3 1266 1266 684 White 0
9 AM Wed 44 44 S 3 1266 1266 684 White 0
10 AM Wed 45 45 S 3 1266 1266 684 White 0
11 AM Wed 46 46 NW 5 1266 1266 684 White 0
12 Noon Wed 50 50 NW 5 1493 1493 911 White 0
1 PM Wed 51 51 NW 5 1710 1710 1128 White 0
2 PM Wed 49 49 NW 5 1275 1275 693 White 0
3 PM Wed 48 48 NW 5 1266 1266 684 White 0
4 PM Wed 47 47 NW 5 1266 1266 684 White 0
5 PM Wed 46 46 E 5 1266 1266 684 White 0
6 PM Wed 46 46 E 5 1266 1266 684 White 0
7 PM Wed 42 42 E 5 1266 1266 684 White 0
8 PM Wed 41 41 E 5 1266 1266 684 White 0
9 PM Wed 41 41 E 5 1266 1266 684 White 0
10 PM Wed 39 39 E 5 0 582 0 Blue 0
11 PM Wed 38 38 E 3 0 582 0 Blue 0
12 Midnight Thu 39 39 E 3 0 582 0 Blue 0
1 AM Thu 37 37 E 3 0 582 0 Blue 0
2 AM Thu 36 36 E 3 0 582 0 Blue 0
3 AM Thu 38 38 E 3 0 582 0 Blue 0
4 AM Thu 36 36 E 3 0 582 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