Detailed Predictions for: Weaver Bally
Launch Lat, Long, Altitude (f): 40.796231, -123.00509, 6900
LZ Altitude (f): 1480
Sounding

Station:

 KOAK

Date/Time:

 21 SEP 2021

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 Tue 58 58 ENE 19 28 5151 6900 0 Blue 0
1 AM Tue 58 58 ENE 19 28 5151 6900 0 Blue 0
2 AM Tue 58 58 ENE 13 18 5151 6900 0 Blue 0
3 AM Tue 58 58 ENE 13 18 5151 6900 0 Blue 0
4 AM Tue 58 58 ENE 13 18 5151 6900 0 Blue 0
5 AM Tue 58 58 ENE 9 11 5151 6900 0 Blue 0
6 AM Tue 60 60 ENE 9 11 5151 6900 0 Blue 0
7 AM Tue 58 58 ENE 9 11 5151 6900 0 Blue 0
8 AM Tue 58 58 E 5 8 5151 6900 0 Blue 0
9 AM Tue 61 62 E 5 8 5151 6900 0 Blue 0
10 AM Tue 62 64 E 5 8 5151 6900 0 Blue 0
11 AM Tue 64 67 ESE 8 10 5151 6900 0 Blue 0
12 Noon Tue 67 71 ESE 8 10 5803 6900 0 Blue 0
1 PM Tue 69 73 ESE 8 10 6918 6900 0 Blue 0
2 PM Tue 72 76 SE 8 10 7587 6900 0 Blue 3
3 PM Tue 73 76 SE 8 10 7587 6900 0 Blue 3
4 PM Tue 73 75 SE 8 10 7348 6900 0 Blue 2
5 PM Tue 73 74 S 5 8 7138 6900 0 Blue 1
6 PM Tue 71 71 S 5 8 5803 6900 0 Blue 0
7 PM Tue 67 67 S 5 8 5151 6900 0 Blue 0
8 PM Tue 64 64 SW 1 1 5151 6900 0 Blue 0
9 PM Tue 66 66 SW 1 1 5151 6900 0 Blue 0
10 PM Tue 64 64 SW 1 1 5151 6900 0 Blue 0
11 PM Tue 63 63 S 2 3 5151 6900 0 Blue 0
12 Midnight Wed 63 63 S 2 3 5151 6900 0 Blue 0
1 AM Wed 62 62 S 2 3 5151 6900 0 Blue 0
2 AM Wed 60 60 S 3 4 5151 6900 0 Blue 0
3 AM Wed 59 59 S 3 4 5151 6900 0 Blue 0
4 AM Wed 59 59 S 3 4 5151 6900 0 Blue 0
5 AM Wed 59 59 SSE 3 4 5151 6900 0 Blue 0
6 AM Wed 60 60 SSE 3 4 5151 6900 0 Blue 0
7 AM Wed 58 58 SSE 3 4 5151 6900 0 Blue 0
8 AM Wed 58 58 SW 4 5 5151 6900 0 Blue 0
9 AM Wed 60 60 SW 4 5 5151 6900 0 Blue 0
10 AM Wed 60 61 SW 4 5 5151 6900 0 Blue 0
11 AM Wed 61 64 W 8 10 5151 6900 0 Blue 0
12 Noon Wed 64 68 W 8 10 5151 6900 0 Blue 0
1 PM Wed 66 70 W 8 10 5218 6900 0 Blue 0
2 PM Wed 67 71 W 11 14 5803 6900 0 Blue 0
3 PM Wed 68 72 W 11 14 6370 6900 0 Blue 0
4 PM Wed 68 70 W 11 14 5218 6900 0 Blue 0
5 PM Wed 67 68 W 8 10 5151 6900 0 Blue 0
6 PM Wed 66 66 W 8 10 5151 6900 0 Blue 0
7 PM Wed 64 64 W 8 10 5151 6900 0 Blue 0
8 PM Wed 62 62 N 5 8 5151 6900 0 Blue 0
9 PM Wed 61 61 N 5 8 5151 6900 0 Blue 0
10 PM Wed 61 61 N 5 8 5151 6900 0 Blue 0
11 PM Wed 60 60 NE 4 5 5151 6900 0 Blue 0
12 Midnight Thu 59 59 NE 4 5 5151 6900 0 Blue 0
1 AM Thu 58 58 NE 4 5 5151 6900 0 Blue 0
2 AM Thu 57 57 ENE 9 11 5151 6900 0 Blue 0
3 AM Thu 57 57 ENE 9 11 5151 6900 0 Blue 0
4 AM Thu 57 57 ENE 9 11 5151 6900 0 Blue 0
5 AM Thu 56 56 NE 12 16 5151 6900 0 Blue 0
6 AM Thu 56 56 NE 12 16 5151 6900 0 Blue 0
7 AM Thu 56 56 NE 12 16 5151 6900 0 Blue 0
8 AM Thu 56 56 ENE 9 11 5151 6900 0 Blue 0
9 AM Thu 58 58 ENE 9 11 5151 6900 0 Blue 0
10 AM Thu 60 61 ENE 9 11 5151 6900 0 Blue 0
11 AM Thu 63 66 ENE 6 9 5151 6900 0 Blue 0
12 Noon Thu 65 69 ENE 6 9 5151 6900 0 Blue 0
1 PM Thu 68 72 ENE 6 9 6370 6900 0 Blue 0
2 PM Thu 70 74 E 12 16 7138 6900 0 Blue 1
3 PM Thu 71 74 E 12 16 7138 6900 0 Blue 1
4 PM Thu 72 74 E 12 16 7138 6900 0 Blue 1
5 PM Thu 72 73 E 12 16 6918 6900 0 Blue 0
6 PM Thu 70 70 E 12 16 5218 6900 0 Blue 0
7 PM Thu 69 69 E 12 16 5151 6900 0 Blue 0
8 PM Thu 67 67 ENE 8 10 5151 6900 0 Blue 0
9 PM Thu 67 67 ENE 8 10 5151 6900 0 Blue 0
10 PM Thu 67 67 ENE 8 10 5151 6900 0 Blue 0
11 PM Thu 67 67 NE 6 9 5151 6900 0 Blue 0
12 Midnight Fri 67 67 NE 6 9 5151 6900 0 Blue 0
1 AM Fri 65 65 NE 6 9 5151 6900 0 Blue 0
2 AM Fri 64 64 NE 6 9 5151 6900 0 Blue 0
3 AM Fri 63 63 NE 6 9 5151 6900 0 Blue 0
4 AM Fri 61 61 NE 6 9 5151 6900 0 Blue 0
5 AM Fri 61 61 NE 6 9 5151 6900 0 Blue 0
6 AM Fri 60 60 NE 6 9 5151 6900 0 Blue 0
7 AM Fri 60 60 NE 6 9 5151 6900 0 Blue 0
8 AM Fri 61 61 NE 6 9 5151 6900 0 Blue 0
9 AM Fri 62 63 NE 6 9 5151 6900 0 Blue 0
10 AM Fri 64 66 NE 6 9 5151 6900 0 Blue 0
11 AM Fri 66 69 SE 4 5 5151 6900 0 Blue 0
12 Noon Fri 69 73 SE 4 5 6918 6900 0 Blue 0
1 PM Fri 72 77 SE 4 5 7842 7126 226 Blue 4
2 PM Fri 74 79 SE 4 5 8104 7569 669 Blue 6
3 PM Fri 75 79 SE 4 5 8104 7569 669 Blue 6
4 PM Fri 75 78 SE 4 5 7980 7335 435 Blue 5
5 PM Fri 74 75 SW 3 4 7348 6900 0 Blue 2
6 PM Fri 72 72 SW 3 4 6370 6900 0 Blue 0
7 PM Fri 69 69 SW 3 4 5151 6900 0 Blue 0
8 PM Fri 67 67 SW 3 4 5151 6900 0 Blue 0
9 PM Fri 66 66 SW 3 4 5151 6900 0 Blue 0
10 PM Fri 66 66 SW 3 4 5151 6900 0 Blue 0
11 PM Fri 66 66 NNE 1 1 5151 6900 0 Blue 0
12 Midnight Sat 65 65 NNE 1 1 5151 6900 0 Blue 0
1 AM Sat 64 64 NNE 1 1 5151 6900 0 Blue 0
2 AM Sat 62 62 NNE 1 1 5151 6900 0 Blue 0
3 AM Sat 62 62 NNE 1 1 5151 6900 0 Blue 0
4 AM Sat 61 61 NNE 1 1 5151 6900 0 Blue 0
5 AM Sat 60 60 NNE 3 4 5151 6900 0 Blue 0
6 AM Sat 59 59 NNE 3 4 5151 6900 0 Blue 0
7 AM Sat 59 59 NNE 3 4 5151 6900 0 Blue 0
8 AM Sat 59 59 NNE 3 4 5151 6900 0 Blue 0
9 AM Sat 60 60 NNE 3 4 5151 6900 0 Blue 0
10 AM Sat 62 64 NNE 3 4 5151 6900 0 Blue 0
11 AM Sat 64 67 W 2 3 5151 6900 0 Blue 0
12 Noon Sat 67 71 W 2 3 5803 6900 0 Blue 0
1 PM Sat 70 75 W 2 3 7348 6900 0 Blue 2
2 PM Sat 72 76 W 2 3 7587 6900 0 Blue 3
3 PM Sat 73 77 W 2 3 7842 7126 226 Blue 4
4 PM Sat 73 75 W 2 3 7348 6900 0 Blue 2
5 PM Sat 72 73 W 6 9 6918 6900 0 Blue 0
6 PM Sat 69 69 W 6 9 5151 6900 0 Blue 0
7 PM Sat 67 67 W 6 9 5151 6900 0 Blue 0
8 PM Sat 64 64 W 6 9 5151 6900 0 Blue 0
9 PM Sat 64 64 W 6 9 5151 6900 0 Blue 0
10 PM Sat 63 63 W 6 9 5151 6900 0 Blue 0
11 PM Sat 63 63 NNW 4 5 5151 6900 0 Blue 0
12 Midnight Sun 62 62 NNW 4 5 5151 6900 0 Blue 0
1 AM Sun 61 61 NNW 4 5 5151 6900 0 Blue 0
2 AM Sun 59 59 NNW 4 5 5151 6900 0 Blue 0
3 AM Sun 59 59 NNW 4 5 5151 6900 0 Blue 0
4 AM Sun 59 59 NNW 4 5 5151 6900 0 Blue 0
5 AM Sun 58 58 NE 3 4 5151 6900 0 Blue 0
6 AM Sun 58 58 NE 3 4 5151 6900 0 Blue 0
7 AM Sun 57 57 NE 3 4 5151 6900 0 Blue 0
8 AM Sun 57 57 NE 3 4 5151 6900 0 Blue 0
9 AM Sun 58 58 NE 3 4 5151 6900 0 Blue 0
10 AM Sun 60 61 NE 3 4 5151 6900 0 Blue 0
11 AM Sun 62 65 S 3 4 5151 6900 0 Blue 0
12 Noon Sun 64 68 S 3 4 5151 6900 0 Blue 0
1 PM Sun 67 71 S 3 4 5803 6900 0 Blue 0
2 PM Sun 69 73 S 3 4 6918 6900 0 Blue 0
3 PM Sun 70 73 S 3 4 6918 6900 0 Blue 0
4 PM Sun 70 72 S 3 4 6370 6900 0 Blue 0
5 PM Sun 69 70 W 4 5 5218 6900 0 Blue 0
6 PM Sun 67 67 W 4 5 5151 6900 0 Blue 0
7 PM Sun 65 65 W 4 5 5151 6900 0 Blue 0
8 PM Sun 63 63 W 4 5 5151 6900 0 Blue 0
9 PM Sun 62 62 W 4 5 5151 6900 0 Blue 0
10 PM Sun 61 61 W 4 5 5151 6900 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]