Detailed Predictions for: BJ
Launch Lat, Long, Altitude (f): 48.8605, -122.126, 582
LZ Altitude (f): 180
Sounding

Station:

 KOTX

Date/Time:

 25 APR 2024

Temp/Wind data from:

NOAA Digital Forecast

Site Forecasts
Time
(Local)		 High
Temp
Puddle
Temp
Wind
 (mph)		 Wind
 Gust		 Thermal
Ceiling
(ft)		 Soaring
Ceiling
(ft)		 Above
Launch
(ft)		 Thermal
Type		 Thermal
Index
(F)
12 Midnight Thu 43 43 S 1 1 1263 1263 681 White 0
1 AM Thu 42 42 S 1 1 0 582 0 Blue 0
2 AM Thu 41 41 SE 1 1 0 582 0 Blue 0
3 AM Thu 41 41 S 4 6 0 582 0 Blue 0
4 AM Thu 41 41 SSE 4 6 0 582 0 Blue 0
5 AM Thu 40 40 ENE 3 4 0 582 0 Blue 0
6 AM Thu 42 42 ENE 3 4 0 582 0 Blue 0
7 AM Thu 41 41 ENE 3 4 0 582 0 Blue 0
8 AM Thu 42 42 S 5 8 0 582 0 Blue 0
9 AM Thu 45 45 S 5 8 1263 1263 681 White 0
10 AM Thu 45 45 S 5 8 1263 1263 681 White 0
11 AM Thu 46 46 S 11 16 1263 1263 681 White 0
12 Noon Thu 49 49 S 11 16 1263 1263 681 White 0
1 PM Thu 50 50 S 11 16 1263 582 0 White 0
2 PM Thu 49 49 S 12 17 1263 1263 681 White 0
3 PM Thu 49 49 S 12 17 1263 1263 681 White 0
4 PM Thu 50 50 S 12 17 1263 582 0 White 0
5 PM Thu 49 49 S 12 17 1263 1263 681 White 0
6 PM Thu 49 49 S 12 17 1263 1263 681 White 0
7 PM Thu 48 48 S 12 17 1263 1263 681 White 0
8 PM Thu 45 45 S 9 13 1263 1263 681 White 0
9 PM Thu 45 45 S 9 13 1263 1263 681 White 0
10 PM Thu 43 43 S 9 13 1263 1263 681 White 0
11 PM Thu 43 43 S 9 12 1263 1263 681 White 0
12 Midnight Fri 44 44 S 9 12 1263 1263 681 White 0
1 AM Fri 43 43 S 9 12 1263 1263 681 White 0
2 AM Fri 42 42 S 8 11 0 582 0 Blue 0
3 AM Fri 43 43 S 8 11 1263 1263 681 White 0
4 AM Fri 42 42 S 8 11 0 582 0 Blue 0
5 AM Fri 42 42 S 6 9 0 582 0 Blue 0
6 AM Fri 42 42 S 6 9 0 582 0 Blue 0
7 AM Fri 42 42 S 6 9 0 582 0 Blue 0
8 AM Fri 43 43 S 5 9 1263 1263 681 White 0
9 AM Fri 45 45 S 5 9 1263 1263 681 White 0
10 AM Fri 47 47 S 5 9 1263 1263 681 White 0
11 AM Fri 48 48 SSW 5 8 1263 1263 681 White 0
12 Noon Fri 49 49 SSW 5 8 1263 1263 681 White 0
1 PM Fri 51 51 SSW 5 8 1263 582 0 White 0
2 PM Fri 52 52 W 4 6 1263 582 0 White 0
3 PM Fri 52 52 W 4 6 1263 582 0 White 0
4 PM Fri 52 52 W 4 6 1263 582 0 White 0
5 PM Fri 52 52 SSW 5 8 1263 582 0 White 0
6 PM Fri 50 50 SSW 5 8 1263 582 0 White 0
7 PM Fri 49 49 SSW 5 8 1263 1263 681 White 0
8 PM Fri 47 47 SW 3 4 1263 1263 681 White 0
9 PM Fri 46 46 SW 3 4 1263 1263 681 White 0
10 PM Fri 44 44 SW 3 4 1263 1263 681 White 0
11 PM Fri 43 43 S 4 6 1263 1263 681 White 0
12 Midnight Sat 43 43 S 4 6 1263 1263 681 White 0
1 AM Sat 43 43 S 4 6 1263 1263 681 White 0
2 AM Sat 43 43 S 3 4 1263 1263 681 White 0
3 AM Sat 43 43 S 3 4 1263 1263 681 White 0
4 AM Sat 42 42 S 3 4 0 582 0 Blue 0
5 AM Sat 42 42 S 4 6 0 582 0 Blue 0
6 AM Sat 42 42 S 4 6 0 582 0 Blue 0
7 AM Sat 43 43 S 4 6 1263 1263 681 White 0
8 AM Sat 43 43 S 5 8 1263 1263 681 White 0
9 AM Sat 44 44 S 5 8 1263 1263 681 White 0
10 AM Sat 45 45 S 5 8 1263 1263 681 White 0
11 AM Sat 46 46 SSW 9 12 1263 1263 681 White 0
12 Noon Sat 47 47 SSW 9 12 1263 1263 681 White 0
1 PM Sat 49 49 SSW 9 12 1263 1263 681 White 0
2 PM Sat 50 50 SSW 8 11 1263 582 0 White 0
3 PM Sat 50 50 SSW 8 11 1263 582 0 White 0
4 PM Sat 49 49 SSW 8 11 1263 1263 681 White 0
5 PM Sat 49 49 SW 9 12 1263 1263 681 White 0
6 PM Sat 47 47 SW 9 12 1263 1263 681 White 0
7 PM Sat 46 46 SW 9 12 1263 1263 681 White 0
8 PM Sat 44 44 S 8 11 1263 1263 681 White 0
9 PM Sat 43 43 S 8 11 1263 1263 681 White 0
10 PM Sat 43 43 S 8 11 1263 1263 681 White 0
11 PM Sat 42 42 SSE 9 12 0 582 0 Blue 0
12 Midnight Sun 42 42 SSE 9 12 0 582 0 Blue 0
1 AM Sun 41 41 SSE 9 12 0 582 0 Blue 0
2 AM Sun 41 41 SSE 9 12 0 582 0 Blue 0
3 AM Sun 41 41 SSE 9 12 0 582 0 Blue 0
4 AM Sun 41 41 SSE 9 12 0 582 0 Blue 0
5 AM Sun 41 41 SSE 10 14 0 582 0 Blue 0
6 AM Sun 41 41 SSE 10 14 0 582 0 Blue 0
7 AM Sun 42 42 SSE 10 14 0 582 0 Blue 0
8 AM Sun 42 42 S 10 14 0 582 0 Blue 0
9 AM Sun 43 43 S 10 14 1263 1263 681 White 0
10 AM Sun 45 45 S 10 14 1263 1263 681 White 0
11 AM Sun 46 46 SSW 11 16 1263 1263 681 White 0
12 Noon Sun 47 47 SSW 11 16 1263 1263 681 White 0
1 PM Sun 47 47 SSW 11 16 1263 1263 681 White 0
2 PM Sun 48 48 SSW 11 16 1263 1263 681 White 0
3 PM Sun 48 48 SSW 11 16 1263 1263 681 White 0
4 PM Sun 48 48 SSW 11 16 1263 1263 681 White 0
5 PM Sun 48 48 SSW 11 16 1263 1263 681 White 0
6 PM Sun 46 46 SSW 11 16 1263 1263 681 White 0
7 PM Sun 43 43 SSW 11 16 1263 1263 681 White 0
8 PM Sun 41 41 SSW 12 17 0 582 0 Blue 0
9 PM Sun 40 40 SSW 12 17 0 582 0 Blue 0
10 PM Sun 39 39 SSW 12 17 0 582 0 Blue 0
11 PM Sun 38 38 SSW 10 14 0 582 0 Blue 0
12 Midnight Mon 37 37 SSW 10 14 0 582 0 Blue 0
1 AM Mon 37 37 SSW 10 14 0 582 0 Blue 0
2 AM Mon 36 36 S 10 14 0 582 0 Blue 0
3 AM Mon 36 36 S 10 14 0 582 0 Blue 0
4 AM Mon 36 36 S 10 14 0 582 0 Blue 0
5 AM Mon 36 36 S 9 13 0 582 0 Blue 0
6 AM Mon 36 36 S 9 13 0 582 0 Blue 0
7 AM Mon 37 37 S 9 13 0 582 0 Blue 0
8 AM Mon 37 37 S 9 13 0 582 0 Blue 0
9 AM Mon 39 39 S 9 13 0 582 0 Blue 0
10 AM Mon 41 41 S 9 13 0 582 0 Blue 0
11 AM Mon 43 43 SSW 10 16 1263 1263 681 White 0
12 Noon Mon 45 45 SSW 10 16 1263 1263 681 White 0
1 PM Mon 47 47 SSW 10 16 1263 1263 681 White 0
2 PM Mon 49 49 SW 10 16 1263 1263 681 White 0
3 PM Mon 49 49 SW 10 16 1263 1263 681 White 0
4 PM Mon 49 49 SW 10 16 1263 1263 681 White 0
5 PM Mon 49 49 SW 10 14 1263 1263 681 White 0
6 PM Mon 46 46 SW 10 14 1263 1263 681 White 0
7 PM Mon 44 44 SW 10 14 1263 1263 681 White 0
8 PM Mon 41 41 SSW 9 14 0 582 0 Blue 0
9 PM Mon 40 40 SSW 9 14 0 582 0 Blue 0
10 PM Mon 38 38 SSW 9 14 0 582 0 Blue 0
11 PM Mon 37 37 SSE 8 11 0 582 0 Blue 0
12 Midnight Tue 37 37 SSE 8 11 0 582 0 Blue 0
1 AM Tue 36 36 SSE 8 11 0 582 0 Blue 0
2 AM Tue 36 36 SE 6 11 0 582 0 Blue 0
3 AM Tue 36 36 SE 6 11 0 582 0 Blue 0
4 AM Tue 35 35 SE 6 11 0 582 0 Blue 0
5 AM Tue 35 35 ESE 6 11 0 582 0 Blue 0
6 AM Tue 36 36 ESE 6 11 0 582 0 Blue 0
7 AM Tue 37 37 ESE 6 11 0 582 0 Blue 0
8 AM Tue 38 38 ESE 8 11 0 582 0 Blue 0
9 AM Tue 41 41 ESE 8 11 0 582 0 Blue 0
10 AM Tue 43 43 ESE 8 11 1263 1263 681 White 0
11 AM Tue 46 47 S 9 13 1263 1263 681 White 0
12 Noon Tue 48 49 S 9 13 1263 1263 681 White 0
1 PM Tue 50 51 S 9 13 1263 582 0 White 0
2 PM Tue 52 53 SSW 10 14 1263 582 0 White 0
3 PM Tue 52 53 SSW 10 14 1263 582 0 White 0
4 PM Tue 51 51 SSW 10 14 1263 582 0 White 0
5 PM Tue 51 51 SW 9 13 1263 582 0 White 0
6 PM Tue 49 49 SW 9 13 1263 1263 681 White 0
7 PM Tue 46 46 SW 9 13 1263 1263 681 White 0
8 PM Tue 44 44 S 9 12 1263 1263 681 White 0
9 PM Tue 42 42 S 9 12 0 582 0 Blue 0
10 PM Tue 41 41 S 9 12 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 or WeatherAPI.com website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the National Weather Service or WeatherAPI.com 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 or WeatherAPI.com website.

Wind Gust: This estimate is taken from the National Weather Service or WeatherAPI.com 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 [email protected]