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

Station:

KOAK

Date/Time:

26 MAY 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 Sun 40 40 NW 3 8021 6900 0 Blue 4
6 AM Sun 40 40 NW 3 8021 6900 0 Blue 4
7 AM Sun 40 40 NW 3 8021 6900 0 Blue 4
8 AM Sun 40 40 N 3 8021 6900 0 Blue 4
9 AM Sun 41 41 N 3 8344 7196 296 Blue 5
10 AM Sun 41 42 N 3 8586 7646 746 White 6
11 AM Sun 43 46 SE 3 9473 9102 2202 White 10
12 Noon Sun 46 50 SE 3 10334 10334 3434 White 14
1 PM Sun 48 52 SE 3 10758 10758 3858 White 16
2 PM Sun 49 51 SE 2 10546 10546 3646 White 15
3 PM Sun 51 52 SE 2 10758 10758 3858 White 16
4 PM Sun 51 52 SE 2 10758 10758 3858 White 16
5 PM Sun 51 51 SW 3 10546 10546 3646 White 15
6 PM Sun 51 51 SW 3 10546 10546 3646 White 15
7 PM Sun 51 51 SW 3 10546 10546 3646 White 15
8 PM Sun 50 50 W 5 10334 10334 3434 White 14
9 PM Sun 50 50 W 5 10334 10334 3434 White 14
10 PM Sun 49 49 W 5 10121 10121 3221 White 13
11 PM Sun 47 47 NW 2 9693 9613 2713 White 11
12 Midnight Mon 47 47 NW 2 9693 9613 2713 White 11
1 AM Mon 47 47 NW 2 9693 9613 2713 White 11
2 AM Mon 46 46 NW 2 9473 9102 2202 White 10
3 AM Mon 45 45 NW 2 9251 8629 1729 White 9
4 AM Mon 45 45 NW 2 9251 8629 1729 White 9
5 AM Mon 44 44 NW 2 9029 8312 1412 White 8
6 AM Mon 45 45 NW 2 9251 8629 1729 White 9
7 AM Mon 46 46 NW 2 9473 9102 2202 White 10
8 AM Mon 47 47 W 3 9693 9613 2713 White 11
9 AM Mon 47 48 W 3 9907 9907 3007 White 12
10 AM Mon 48 50 W 3 10334 10334 3434 White 14
11 AM Mon 51 54 W 7 11182 11182 4282 White 18
12 Noon Mon 53 56 W 7 11573 11339 4439 Blue 20
1 PM Mon 55 58 W 7 11870 11481 4581 Blue 22
2 PM Mon 57 59 W 9 12138 11557 4657 Blue 23
3 PM Mon 57 58 W 9 11870 11481 4581 Blue 22
4 PM Mon 57 58 W 9 11870 11481 4581 Blue 22
5 PM Mon 57 58 W 9 11870 11481 4581 Blue 22
6 PM Mon 56 56 W 9 11573 11339 4439 Blue 20
7 PM Mon 55 55 W 9 11394 11295 4395 White 19
8 PM Mon 54 54 W 9 11182 11182 4282 White 18
9 PM Mon 53 53 W 9 10970 10970 4070 White 17
10 PM Mon 52 52 W 9 10758 10758 3858 White 16
11 PM Mon 51 51 NW 6 10546 10546 3646 White 15
12 Midnight Tue 50 50 NW 6 10334 10334 3434 White 14
1 AM Tue 49 49 NW 6 10121 10121 3221 White 13
2 AM Tue 48 48 NW 6 9907 9907 3007 White 12
3 AM Tue 46 46 NW 6 9473 9102 2202 White 10
4 AM Tue 45 45 NW 6 9251 8629 1729 White 9
5 AM Tue 44 44 N 7 9029 8312 1412 White 8
6 AM Tue 45 45 N 7 9251 8629 1729 White 9
7 AM Tue 47 47 N 7 9693 9613 2713 White 11
8 AM Tue 49 50 N 7 10334 10334 3434 White 14
9 AM Tue 51 53 N 7 10970 10970 4070 White 17
10 AM Tue 53 57 N 7 11650 11404 4504 Blue 21
11 AM Tue 55 60 NW 8 12404 11634 4734 Blue 24
12 Noon Tue 58 64 NW 8 13287 12602 5702 White 28
1 PM Tue 60 66 NW 8 13698 13698 6798 White 30
2 PM Tue 62 67 NW 8 13902 13902 7002 White 31
3 PM Tue 64 68 NW 8 14106 14106 7206 White 32
4 PM Tue 64 67 NW 8 13902 13902 7002 White 31
5 PM Tue 63 65 NW 9 13492 12863 5963 White 29
6 PM Tue 62 63 NW 9 13082 12340 5440 White 27
7 PM Tue 61 61 NW 9 12662 11810 4910 White 25
8 PM Tue 59 59 NW 9 12138 11557 4657 Blue 23
9 PM Tue 57 57 NW 9 11650 11404 4504 Blue 21
10 PM Tue 55 55 NW 9 11394 11295 4395 White 19
11 PM Tue 53 53 NW 7 10970 10970 4070 White 17
12 Midnight Wed 52 52 NW 7 10758 10758 3858 White 16
1 AM Wed 51 51 NW 7 10546 10546 3646 White 15
2 AM Wed 50 50 NW 7 10334 10334 3434 White 14
3 AM Wed 49 49 NW 7 10121 10121 3221 White 13
4 AM Wed 48 48 NW 7 9907 9907 3007 White 12
5 AM Wed 48 48 N 7 9907 9907 3007 White 12
6 AM Wed 49 49 N 7 10121 10121 3221 White 13
7 AM Wed 51 51 N 7 10546 10546 3646 White 15
8 AM Wed 53 54 N 7 11182 11182 4282 White 18
9 AM Wed 55 57 N 7 11650 11404 4504 Blue 21
10 AM Wed 58 61 N 7 12662 11810 4910 White 25
11 AM Wed 60 63 N 6 13082 12340 5440 White 27
12 Noon Wed 62 65 N 6 13492 12863 5963 White 29
1 PM Wed 64 68 N 6 14106 14106 7206 White 32
2 PM Wed 66 69 N 6 14310 14310 7410 White 33
3 PM Wed 66 69 N 6 14310 14310 7410 White 33
4 PM Wed 65 67 N 6 13902 13902 7002 White 31
5 PM Wed 65 66 W 7 13698 13698 6798 White 30
6 PM Wed 64 64 W 7 13287 12602 5702 White 28
7 PM Wed 63 63 W 7 13082 12340 5440 White 27
8 PM Wed 62 62 W 7 12873 12076 5176 White 26
9 PM Wed 60 60 W 7 12404 11634 4734 Blue 24
10 PM Wed 58 58 W 7 11870 11481 4581 Blue 22
11 PM Wed 56 56 NW 6 11573 11339 4439 Blue 20
12 Midnight Thu 55 55 NW 6 11394 11295 4395 White 19
1 AM Thu 54 54 NW 6 11182 11182 4282 White 18
2 AM Thu 53 53 NW 6 10970 10970 4070 White 17
3 AM Thu 52 52 NW 6 10758 10758 3858 White 16
4 AM Thu 51 51 NW 6 10546 10546 3646 White 15
5 AM Thu 51 51 N 5 10546 10546 3646 White 15
6 AM Thu 52 52 N 5 10758 10758 3858 White 16
7 AM Thu 54 54 N 5 11182 11182 4282 White 18
8 AM Thu 56 57 N 5 11650 11404 4504 Blue 21
9 AM Thu 57 59 N 5 12138 11557 4657 Blue 23
10 AM Thu 59 62 N 5 12873 12076 5176 White 26
11 AM Thu 61 64 W 5 13287 12602 5702 White 28
12 Noon Thu 63 66 W 5 13698 13698 6798 White 30
1 PM Thu 65 69 W 5 14310 14310 7410 White 33
2 PM Thu 67 70 W 5 14514 14514 7614 White 34
3 PM Thu 68 71 W 5 14717 14717 7817 White 35
4 PM Thu 67 69 W 5 14310 14310 7410 White 33
5 PM Thu 67 69 W 7 14310 14310 7410 White 33
6 PM Thu 65 66 W 7 13698 13698 6798 White 30
7 PM Thu 64 64 W 7 13287 12602 5702 White 28
8 PM Thu 61 61 W 7 12662 11810 4910 White 25
9 PM Thu 59 59 W 7 12138 11557 4657 Blue 23
10 PM Thu 57 57 W 7 11650 11404 4504 Blue 21
11 PM Thu 55 55 NW 5 11394 11295 4395 White 19
12 Midnight Fri 54 54 NW 5 11182 11182 4282 White 18
1 AM Fri 53 53 NW 5 10970 10970 4070 White 17
2 AM Fri 52 52 NW 5 10758 10758 3858 White 16
3 AM Fri 51 51 NW 5 10546 10546 3646 White 15
4 AM Fri 50 50 NW 5 10334 10334 3434 White 14
5 AM Fri 50 50 N 5 10334 10334 3434 White 14
6 AM Fri 51 51 N 5 10546 10546 3646 White 15
7 AM Fri 53 53 N 5 10970 10970 4070 White 17
8 AM Fri 55 56 N 5 11573 11339 4439 Blue 20
9 AM Fri 57 59 N 5 12138 11557 4657 Blue 23
10 AM Fri 58 62 N 5 12873 12076 5176 White 26
11 AM Fri 60 65 NW 6 13492 12863 5963 White 29
12 Noon Fri 62 67 NW 6 13902 13902 7002 White 31
1 PM Fri 65 71 NW 6 14717 14717 7817 White 35
2 PM Fri 68 74 NW 6 15325 15325 8425 White 38
3 PM Fri 69 74 NW 6 15325 15325 8425 White 38
4 PM Fri 68 71 NW 6 14717 14717 7817 White 35
5 PM Fri 68 70 W 8 14514 14514 7614 White 34
6 PM Fri 67 68 W 8 14106 14106 7206 White 32
7 PM Fri 66 66 W 8 13698 13698 6798 White 30
8 PM Fri 64 64 W 8 13287 12602 5702 White 28
9 PM Fri 62 62 W 8 12873 12076 5176 White 26
10 PM Fri 59 59 W 8 12138 11557 4657 Blue 23
11 PM Fri 57 57 N 6 11650 11404 4504 Blue 21
12 Midnight Sat 56 56 N 6 11573 11339 4439 Blue 20
1 AM Sat 55 55 N 6 11394 11295 4395 White 19
2 AM Sat 55 55 N 6 11394 11295 4395 White 19
3 AM Sat 53 53 N 6 10970 10970 4070 White 17
4 AM Sat 52 52 N 6 10758 10758 3858 White 16

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