Detailed Predictions for: Weaver Bally
Launch Altitude (f): 6900
LZ Altitude (f): 1480
Sounding

Station:

KOAK

Date/Time:

23 SEP 2017

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 Sat 44 44 NE 9 5851 6900 0 Blue 0
6 AM Sat 44 44 NE 9 5851 6900 0 Blue 0
7 AM Sat 46 46 NE 9 6912 6900 0 Blue 2
8 AM Sat 47 47 NE 8 7497 6900 0 Blue 3
9 AM Sat 49 50 NE 8 9448 7442 542 Blue 6
10 AM Sat 52 54 NE 8 10626 9933 3033 White 10
11 AM Sat 54 56 NE 2 11052 10691 3791 White 12
12 Noon Sat 57 60 NE 2 11896 11896 4996 White 16
1 PM Sat 59 63 NE 2 12525 12525 5625 White 19
2 PM Sat 61 64 NW 2 12734 12679 5779 White 20
3 PM Sat 63 66 NW 2 13151 12956 6056 White 22
4 PM Sat 64 66 NW 2 13151 12956 6056 White 22
5 PM Sat 64 65 NW 7 12942 12811 5911 White 21
6 PM Sat 63 63 NW 7 12525 12525 5625 White 19
7 PM Sat 62 62 NW 7 12315 12315 5415 White 18
8 PM Sat 60 60 NE 2 11896 11896 4996 White 16
9 PM Sat 58 58 NE 2 11476 11476 4576 White 14
10 PM Sat 55 55 NE 2 10839 10324 3424 White 11
11 PM Sat 54 54 NE 3 10626 9933 3033 White 10
12 Midnight Sun 52 52 NE 3 10197 8806 1906 White 8
1 AM Sun 51 51 NE 3 9981 8185 1285 White 7
2 AM Sun 50 50 NE 3 9448 7442 542 Blue 6
3 AM Sun 50 50 NE 3 9448 7442 542 Blue 6
4 AM Sun 50 50 NE 3 9448 7442 542 Blue 6
5 AM Sun 51 51 NE 3 9981 8185 1285 White 7
6 AM Sun 52 52 NE 3 10197 8806 1906 White 8
7 AM Sun 53 53 NE 3 10412 9346 2446 White 9
8 AM Sun 54 54 NE 3 10626 9933 3033 White 10
9 AM Sun 56 57 NE 3 11264 11107 4207 White 13
10 AM Sun 58 60 NE 3 11896 11896 4996 White 16
11 AM Sun 60 63 SE 3 12525 12525 5625 White 19
12 Noon Sun 63 67 SE 3 13359 13107 6207 White 23
1 PM Sun 65 69 SE 3 13773 13507 6607 White 25
2 PM Sun 67 71 SW 5 14185 14185 7285 White 27
3 PM Sun 69 72 SW 5 14391 14391 7491 White 28
4 PM Sun 70 72 SW 5 14391 14391 7491 White 28
5 PM Sun 70 71 W 5 14185 14185 7285 White 27
6 PM Sun 69 69 W 5 13773 13507 6607 White 25
7 PM Sun 67 67 W 5 13359 13107 6207 White 23
8 PM Sun 65 65 W 5 12942 12811 5911 White 21
9 PM Sun 62 62 W 5 12315 12315 5415 White 18
10 PM Sun 60 60 W 5 11896 11896 4996 White 16
11 PM Sun 57 57 NE 7 11264 11107 4207 White 13
12 Midnight Mon 55 55 NE 7 10839 10324 3424 White 11
1 AM Mon 54 54 NE 7 10626 9933 3033 White 10
2 AM Mon 53 53 NE 7 10412 9346 2446 White 9
3 AM Mon 52 52 NE 7 10197 8806 1906 White 8
4 AM Mon 52 52 NE 7 10197 8806 1906 White 8
5 AM Mon 53 53 NE 6 10412 9346 2446 White 9
6 AM Mon 54 54 NE 6 10626 9933 3033 White 10
7 AM Mon 55 55 NE 6 10839 10324 3424 White 11
8 AM Mon 57 57 NE 6 11264 11107 4207 White 13
9 AM Mon 59 59 NE 6 11686 11686 4786 White 15
10 AM Mon 61 63 NE 6 12525 12525 5625 White 19
11 AM Mon 63 66 N 5 13151 12956 6056 White 22
12 Noon Mon 66 70 N 5 13979 13915 7015 White 26
1 PM Mon 68 73 N 5 14596 14596 7696 White 29
2 PM Mon 70 74 N 5 14801 14801 7901 White 30
3 PM Mon 71 75 N 5 15005 15005 8105 White 31
4 PM Mon 72 74 N 5 14801 14801 7901 White 30
5 PM Mon 72 73 N 8 14596 14596 7696 White 29
6 PM Mon 71 71 N 8 14185 14185 7285 White 27
7 PM Mon 69 69 N 8 13773 13507 6607 White 25
8 PM Mon 67 67 N 8 13359 13107 6207 White 23
9 PM Mon 65 65 N 8 12942 12811 5911 White 21
10 PM Mon 63 63 N 8 12525 12525 5625 White 19
11 PM Mon 60 60 NE 12 11896 11896 4996 White 16
12 Midnight Tue 58 58 NE 12 11476 11476 4576 White 14
1 AM Tue 57 57 NE 12 11264 11107 4207 White 13
2 AM Tue 56 56 NE 12 11052 10691 3791 White 12
3 AM Tue 55 55 NE 12 10839 10324 3424 White 11
4 AM Tue 55 55 NE 12 10839 10324 3424 White 11
5 AM Tue 56 56 NE 10 11052 10691 3791 White 12
6 AM Tue 57 57 NE 10 11264 11107 4207 White 13
7 AM Tue 58 58 NE 10 11476 11476 4576 White 14
8 AM Tue 60 60 NE 10 11896 11896 4996 White 16
9 AM Tue 63 64 NE 10 12734 12679 5779 White 20
10 AM Tue 65 67 NE 10 13359 13107 6207 White 23
11 AM Tue 68 71 NE 5 14185 14185 7285 White 27
12 Noon Tue 70 74 NE 5 14801 14801 7901 White 30
1 PM Tue 72 77 NE 5 15413 15413 8513 White 33
2 PM Tue 74 79 NE 5 15817 15817 8917 White 35
3 PM Tue 75 79 NE 5 15817 15817 8917 White 35
4 PM Tue 76 78 NE 5 15617 15617 8717 White 34
5 PM Tue 76 77 E 5 15413 15413 8513 White 33
6 PM Tue 75 75 E 5 15005 15005 8105 White 31
7 PM Tue 73 73 E 5 14596 14596 7696 White 29
8 PM Tue 71 71 E 5 14185 14185 7285 White 27
9 PM Tue 68 68 E 5 13566 13258 6358 White 24
10 PM Tue 65 65 E 5 12942 12811 5911 White 21
11 PM Tue 62 62 E 5 12315 12315 5415 White 18
12 Midnight Wed 60 60 E 5 11896 11896 4996 White 16
1 AM Wed 58 58 E 5 11476 11476 4576 White 14
2 AM Wed 57 57 E 5 11264 11107 4207 White 13
3 AM Wed 56 56 E 5 11052 10691 3791 White 12
4 AM Wed 56 56 E 5 11052 10691 3791 White 12
5 AM Wed 56 56 E 6 11052 10691 3791 White 12
6 AM Wed 57 57 E 6 11264 11107 4207 White 13
7 AM Wed 58 58 E 6 11476 11476 4576 White 14
8 AM Wed 60 60 E 6 11896 11896 4996 White 16
9 AM Wed 62 63 E 6 12525 12525 5625 White 19
10 AM Wed 64 66 E 6 13151 12956 6056 White 22
11 AM Wed 67 69 E 5 13773 13507 6607 White 25
12 Noon Wed 69 72 E 5 14391 14391 7491 White 28
1 PM Wed 71 75 E 5 15005 15005 8105 White 31
2 PM Wed 74 78 E 5 15617 15617 8717 White 34
3 PM Wed 75 78 E 5 15617 15617 8717 White 34
4 PM Wed 76 78 E 5 15617 15617 8717 White 34
5 PM Wed 76 77 SE 2 15413 15413 8513 White 33
6 PM Wed 75 75 SE 2 15005 15005 8105 White 31
7 PM Wed 73 73 SE 2 14596 14596 7696 White 29
8 PM Wed 71 71 SE 2 14185 14185 7285 White 27
9 PM Wed 68 68 SE 2 13566 13258 6358 White 24
10 PM Wed 66 66 SE 2 13151 12956 6056 White 22
11 PM Wed 63 63 E 3 12525 12525 5625 White 19
12 Midnight Thu 61 61 E 3 12106 12106 5206 White 17
1 AM Thu 59 59 E 3 11686 11686 4786 White 15
2 AM Thu 58 58 E 3 11476 11476 4576 White 14
3 AM Thu 57 57 E 3 11264 11107 4207 White 13
4 AM Thu 57 57 E 3 11264 11107 4207 White 13
5 AM Thu 57 57 E 2 11264 11107 4207 White 13
6 AM Thu 58 58 E 2 11476 11476 4576 White 14
7 AM Thu 60 60 E 2 11896 11896 4996 White 16
8 AM Thu 62 62 E 2 12315 12315 5415 White 18
9 AM Thu 64 64 E 2 12734 12679 5779 White 20
10 AM Thu 66 67 E 2 13359 13107 6207 White 23
11 AM Thu 69 72 SE 2 14391 14391 7491 White 28
12 Noon Thu 71 75 SE 2 15005 15005 8105 White 31
1 PM Thu 73 77 SE 2 15413 15413 8513 White 33
2 PM Thu 75 79 SE 2 15817 15817 8917 White 35
3 PM Thu 76 79 SE 2 15817 15817 8917 White 35
4 PM Thu 76 78 SE 2 15617 15617 8717 White 34
5 PM Thu 76 77 SW 3 15413 15413 8513 White 33
6 PM Thu 74 74 SW 3 14801 14801 7901 White 30
7 PM Thu 72 72 SW 3 14391 14391 7491 White 28
8 PM Thu 70 70 SW 3 13979 13915 7015 White 26
9 PM Thu 67 67 SW 3 13359 13107 6207 White 23
10 PM Thu 65 65 SW 3 12942 12811 5911 White 21
11 PM Thu 62 62 SW 2 12315 12315 5415 White 18
12 Midnight Fri 60 60 SW 2 11896 11896 4996 White 16
1 AM Fri 59 59 SW 2 11686 11686 4786 White 15
2 AM Fri 58 58 SW 2 11476 11476 4576 White 14
3 AM Fri 57 57 SW 2 11264 11107 4207 White 13
4 AM Fri 57 57 SW 2 11264 11107 4207 White 13

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