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

Station:

KOAK

Date/Time:

17 JAN 2018

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)
4 AM Wed 40 40 S 6 5112 6900 0 Blue 0
5 AM Wed 39 39 S 6 5112 6900 0 Blue 0
6 AM Wed 40 40 S 6 5112 6900 0 Blue 0
7 AM Wed 39 39 SE 8 5112 6900 0 Blue 0
8 AM Wed 39 39 SE 8 5112 6900 0 Blue 0
9 AM Wed 39 39 SE 8 5112 6900 0 Blue 0
10 AM Wed 40 40 SE 10 5112 6900 0 Blue 0
11 AM Wed 41 41 SE 10 5112 6900 0 Blue 0
12 Noon Wed 42 42 SE 10 5112 6900 0 Blue 0
1 PM Wed 43 43 S 9 5112 6900 0 Blue 0
2 PM Wed 44 44 S 9 5112 6900 0 Blue 0
3 PM Wed 45 45 S 9 5112 6900 0 Blue 0
4 PM Wed 45 45 SE 12 5112 6900 0 Blue 0
5 PM Wed 45 45 SE 12 5112 6900 0 Blue 0
6 PM Wed 45 45 SE 12 5112 6900 0 Blue 0
7 PM Wed 44 44 SE 12 5112 6900 0 Blue 0
8 PM Wed 44 44 SE 12 5112 6900 0 Blue 0
9 PM Wed 43 43 SE 12 5112 6900 0 Blue 0
10 PM Wed 43 43 S 13 5112 6900 0 Blue 0
11 PM Wed 43 43 S 13 5112 6900 0 Blue 0
12 Midnight Thu 43 43 S 13 5112 6900 0 Blue 0
1 AM Thu 44 44 S 18 5112 6900 0 Blue 0
2 AM Thu 44 44 S 18 5112 6900 0 Blue 0
3 AM Thu 44 44 S 18 5112 6900 0 Blue 0
4 AM Thu 43 43 S 13 5112 6900 0 Blue 0
5 AM Thu 42 42 S 13 5112 6900 0 Blue 0
6 AM Thu 40 40 S 13 5112 6900 0 Blue 0
7 AM Thu 39 39 S 13 5112 6900 0 Blue 0
8 AM Thu 37 37 S 13 5112 6900 0 Blue 0
9 AM Thu 35 35 S 13 5112 6900 0 Blue 0
10 AM Thu 34 34 SW 10 5112 6900 0 Blue 0
11 AM Thu 34 34 SW 10 5112 6900 0 Blue 0
12 Noon Thu 34 34 SW 10 5112 6900 0 Blue 0
1 PM Thu 35 35 SW 10 5112 6900 0 Blue 0
2 PM Thu 35 35 SW 10 5112 6900 0 Blue 0
3 PM Thu 36 36 SW 10 5112 6900 0 Blue 0
4 PM Thu 36 36 W 10 5112 6900 0 Blue 0
5 PM Thu 36 36 W 10 5112 6900 0 Blue 0
6 PM Thu 36 36 W 10 5112 6900 0 Blue 0
7 PM Thu 35 35 W 10 5112 6900 0 Blue 0
8 PM Thu 34 34 W 10 5112 6900 0 Blue 0
9 PM Thu 33 33 W 10 5112 6900 0 Blue 0
10 PM Thu 32 32 S 8 5112 6900 0 Blue 0
11 PM Thu 31 31 S 8 5112 6900 0 Blue 0
12 Midnight Fri 30 30 S 8 5112 6900 0 Blue 0
1 AM Fri 30 30 S 8 5112 6900 0 Blue 0
2 AM Fri 29 29 S 8 5112 6900 0 Blue 0
3 AM Fri 29 29 S 8 5112 6900 0 Blue 0
4 AM Fri 28 28 W 8 5112 6900 0 Blue 0
5 AM Fri 28 28 W 8 5112 6900 0 Blue 0
6 AM Fri 27 27 W 8 5112 6900 0 Blue 0
7 AM Fri 26 26 W 8 5112 6900 0 Blue 0
8 AM Fri 26 26 W 8 5112 6900 0 Blue 0
9 AM Fri 26 26 W 8 5112 6900 0 Blue 0
10 AM Fri 26 26 SW 7 5112 6900 0 Blue 0
11 AM Fri 27 27 SW 7 5112 6900 0 Blue 0
12 Noon Fri 28 28 SW 7 5112 6900 0 Blue 0
1 PM Fri 29 29 SW 7 5112 6900 0 Blue 0
2 PM Fri 31 31 SW 7 5112 6900 0 Blue 0
3 PM Fri 32 32 SW 7 5112 6900 0 Blue 0
4 PM Fri 33 33 W 6 5112 6900 0 Blue 0
5 PM Fri 33 33 W 6 5112 6900 0 Blue 0
6 PM Fri 33 33 W 6 5112 6900 0 Blue 0
7 PM Fri 33 33 W 6 5112 6900 0 Blue 0
8 PM Fri 32 32 W 6 5112 6900 0 Blue 0
9 PM Fri 31 31 W 6 5112 6900 0 Blue 0
10 PM Fri 31 31 W 5 5112 6900 0 Blue 0
11 PM Fri 30 30 W 5 5112 6900 0 Blue 0
12 Midnight Sat 30 30 W 5 5112 6900 0 Blue 0
1 AM Sat 29 29 W 5 5112 6900 0 Blue 0
2 AM Sat 29 29 W 5 5112 6900 0 Blue 0
3 AM Sat 28 28 W 5 5112 6900 0 Blue 0
4 AM Sat 28 28 NW 3 5112 6900 0 Blue 0
5 AM Sat 28 28 NW 3 5112 6900 0 Blue 0
6 AM Sat 27 27 NW 3 5112 6900 0 Blue 0
7 AM Sat 27 27 NW 3 5112 6900 0 Blue 0
8 AM Sat 27 27 NW 3 5112 6900 0 Blue 0
9 AM Sat 27 27 NW 3 5112 6900 0 Blue 0
10 AM Sat 28 28 S 5 5112 6900 0 Blue 0
11 AM Sat 29 29 S 5 5112 6900 0 Blue 0
12 Noon Sat 30 30 S 5 5112 6900 0 Blue 0
1 PM Sat 31 31 S 5 5112 6900 0 Blue 0
2 PM Sat 33 33 S 5 5112 6900 0 Blue 0
3 PM Sat 34 34 S 5 5112 6900 0 Blue 0
4 PM Sat 35 35 S 7 5112 6900 0 Blue 0
5 PM Sat 35 35 S 7 5112 6900 0 Blue 0
6 PM Sat 35 35 S 7 5112 6900 0 Blue 0
7 PM Sat 35 35 S 7 5112 6900 0 Blue 0
8 PM Sat 35 35 S 7 5112 6900 0 Blue 0
9 PM Sat 34 34 S 7 5112 6900 0 Blue 0
10 PM Sat 34 34 S 8 5112 6900 0 Blue 0
11 PM Sat 34 34 S 8 5112 6900 0 Blue 0
12 Midnight Sun 34 34 S 8 5112 6900 0 Blue 0
1 AM Sun 34 34 S 8 5112 6900 0 Blue 0
2 AM Sun 34 34 S 8 5112 6900 0 Blue 0
3 AM Sun 34 34 S 8 5112 6900 0 Blue 0
4 AM Sun 34 34 S 12 5112 6900 0 Blue 0
5 AM Sun 33 33 S 12 5112 6900 0 Blue 0
6 AM Sun 33 33 S 12 5112 6900 0 Blue 0
7 AM Sun 32 32 S 12 5112 6900 0 Blue 0
8 AM Sun 32 32 S 12 5112 6900 0 Blue 0
9 AM Sun 32 32 S 12 5112 6900 0 Blue 0
10 AM Sun 32 32 S 8 5112 6900 0 Blue 0
11 AM Sun 32 32 S 8 5112 6900 0 Blue 0
12 Noon Sun 33 33 S 8 5112 6900 0 Blue 0
1 PM Sun 33 33 S 8 5112 6900 0 Blue 0
2 PM Sun 34 34 S 8 5112 6900 0 Blue 0
3 PM Sun 35 35 S 8 5112 6900 0 Blue 0
4 PM Sun 35 35 S 7 5112 6900 0 Blue 0
5 PM Sun 36 36 S 7 5112 6900 0 Blue 0
6 PM Sun 36 36 S 7 5112 6900 0 Blue 0
7 PM Sun 36 36 S 7 5112 6900 0 Blue 0
8 PM Sun 36 36 S 7 5112 6900 0 Blue 0
9 PM Sun 36 36 S 7 5112 6900 0 Blue 0
10 PM Sun 35 35 S 5 5112 6900 0 Blue 0
11 PM Sun 35 35 S 5 5112 6900 0 Blue 0
12 Midnight Mon 34 34 S 5 5112 6900 0 Blue 0
1 AM Mon 33 33 S 5 5112 6900 0 Blue 0
2 AM Mon 32 32 S 5 5112 6900 0 Blue 0
3 AM Mon 32 32 S 5 5112 6900 0 Blue 0
4 AM Mon 31 31 W 6 5112 6900 0 Blue 0
5 AM Mon 31 31 W 6 5112 6900 0 Blue 0
6 AM Mon 31 31 W 6 5112 6900 0 Blue 0
7 AM Mon 31 31 W 6 5112 6900 0 Blue 0
8 AM Mon 31 31 W 6 5112 6900 0 Blue 0
9 AM Mon 32 32 W 6 5112 6900 0 Blue 0
10 AM Mon 33 33 W 6 5112 6900 0 Blue 0
11 AM Mon 33 33 W 6 5112 6900 0 Blue 0
12 Noon Mon 34 34 W 6 5112 6900 0 Blue 0
1 PM Mon 34 34 W 6 5112 6900 0 Blue 0
2 PM Mon 35 35 W 6 5112 6900 0 Blue 0
3 PM Mon 35 35 W 6 5112 6900 0 Blue 0
4 PM Mon 35 35 SW 3 5112 6900 0 Blue 0
5 PM Mon 35 35 SW 3 5112 6900 0 Blue 0
6 PM Mon 34 34 SW 3 5112 6900 0 Blue 0
7 PM Mon 33 33 SW 3 5112 6900 0 Blue 0
8 PM Mon 33 33 SW 3 5112 6900 0 Blue 0
9 PM Mon 32 32 SW 3 5112 6900 0 Blue 0
10 PM Mon 32 32 E 2 5112 6900 0 Blue 0
11 PM Mon 32 32 E 2 5112 6900 0 Blue 0
12 Midnight Tue 32 32 E 2 5112 6900 0 Blue 0
1 AM Tue 32 32 E 2 5112 6900 0 Blue 0
2 AM Tue 33 33 E 2 5112 6900 0 Blue 0
3 AM Tue 33 33 E 2 5112 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 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