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

Station:

 KOAK

Date/Time:

 4 FEB 2012

Temp/Wind data from:

NOAA Digital Forecast

Time
(Local)		 High
Temp
Puddle
Temp
Wind
 (mph)		 Thermal
Ceiling
(ft)		 Soaring
Ceiling
(ft)		 Above
Launch
(ft)		 Thermal
Type		 Thermal
Index
(F)
4 AM Sat 36 36 SE 6 4633 6900 0 Blue 0
5 AM Sat 36 36 SE 6 4633 6900 0 Blue 0
6 AM Sat 36 36 SE 6 4633 6900 0 Blue 0
7 AM Sat 36 36 SE 7 4633 6900 0 Blue 0
8 AM Sat 38 38 SE 7 4642 6900 0 Blue 0
9 AM Sat 39 39 SE 7 4828 6900 0 Blue 0
10 AM Sat 41 42 SE 7 5385 6900 0 Blue 0
11 AM Sat 44 45 SE 7 5939 6900 0 Blue 0
12 Noon Sat 45 47 SE 7 6343 6900 0 Blue 1
1 PM Sat 46 48 SE 7 6532 6900 0 Blue 2
2 PM Sat 45 46 SE 7 6123 6900 0 Blue 0
3 PM Sat 43 44 SE 7 5755 6900 0 Blue 0
4 PM Sat 41 41 SE 7 5200 6900 0 Blue 0
5 PM Sat 38 38 SE 7 4642 6900 0 Blue 0
6 PM Sat 36 36 SE 7 4633 6900 0 Blue 0
7 PM Sat 34 34 SE 7 4633 6900 0 Blue 0
8 PM Sat 34 34 SE 7 4633 6900 0 Blue 0
9 PM Sat 34 34 SE 7 4633 6900 0 Blue 0
10 PM Sat 35 35 SE 6 4633 6900 0 Blue 0
11 PM Sat 35 35 SE 6 4633 6900 0 Blue 0
12 Midnight Sun 35 35 SE 6 4633 6900 0 Blue 0
1 AM Sun 35 35 SE 5 4633 6900 0 Blue 0
2 AM Sun 35 35 SE 5 4633 6900 0 Blue 0
3 AM Sun 36 36 SE 5 4633 6900 0 Blue 0
4 AM Sun 36 36 E 5 4633 6900 0 Blue 0
5 AM Sun 36 36 E 5 4633 6900 0 Blue 0
6 AM Sun 37 37 E 5 4633 6900 0 Blue 0
7 AM Sun 38 38 E 5 4642 6900 0 Blue 0
8 AM Sun 40 40 E 5 5014 6900 0 Blue 0
9 AM Sun 42 42 E 5 5385 6900 0 Blue 0
10 AM Sun 45 46 E 6 6123 6900 0 Blue 0
11 AM Sun 47 48 E 6 6532 6900 0 Blue 2
12 Noon Sun 48 50 E 6 6735 6900 0 Blue 4
1 PM Sun 48 49 E 7 6633 6900 0 Blue 3
2 PM Sun 47 48 E 7 6532 6900 0 Blue 2
3 PM Sun 45 45 E 7 5939 6900 0 Blue 0
4 PM Sun 43 43 E 7 5570 6900 0 Blue 0
5 PM Sun 40 40 E 7 5014 6900 0 Blue 0
6 PM Sun 37 37 E 7 4633 6900 0 Blue 0
7 PM Sun 35 35 E 7 4633 6900 0 Blue 0
8 PM Sun 35 35 E 7 4633 6900 0 Blue 0
9 PM Sun 35 35 E 7 4633 6900 0 Blue 0
10 PM Sun 36 36 SE 7 4633 6900 0 Blue 0
11 PM Sun 37 37 SE 7 4633 6900 0 Blue 0
12 Midnight Mon 37 37 SE 7 4633 6900 0 Blue 0
1 AM Mon 38 38 SE 7 4642 6900 0 Blue 0
2 AM Mon 37 37 SE 7 4633 6900 0 Blue 0
3 AM Mon 37 37 SE 7 4633 6900 0 Blue 0
4 AM Mon 37 37 SE 5 4633 6900 0 Blue 0
5 AM Mon 37 37 SE 5 4633 6900 0 Blue 0
6 AM Mon 37 37 SE 5 4633 6900 0 Blue 0
7 AM Mon 38 38 SE 5 4642 6900 0 Blue 0
8 AM Mon 39 39 SE 5 4828 6900 0 Blue 0
9 AM Mon 41 41 SE 5 5200 6900 0 Blue 0
10 AM Mon 42 42 SE 12 5385 6900 0 Blue 0
11 AM Mon 44 45 SE 12 5939 6900 0 Blue 0
12 Noon Mon 45 46 SE 12 6123 6900 0 Blue 0
1 PM Mon 45 46 SE 12 6123 6900 0 Blue 0
2 PM Mon 44 45 SE 12 5939 6900 0 Blue 0
3 PM Mon 43 43 SE 12 5570 6900 0 Blue 0
4 PM Mon 41 41 SE 14 5200 6900 0 Blue 0
5 PM Mon 40 40 SE 14 5014 6900 0 Blue 0
6 PM Mon 39 39 SE 14 4828 6900 0 Blue 0
7 PM Mon 38 38 SE 14 4642 6900 0 Blue 0
8 PM Mon 38 38 SE 14 4642 6900 0 Blue 0
9 PM Mon 39 39 SE 14 4828 6900 0 Blue 0
10 PM Mon 39 39 SE 14 4828 6900 0 Blue 0
11 PM Mon 40 40 SE 14 5014 6900 0 Blue 0
12 Midnight Tue 40 40 SE 14 5014 6900 0 Blue 0
1 AM Tue 40 40 SE 14 5014 6900 0 Blue 0
2 AM Tue 39 39 SE 14 4828 6900 0 Blue 0
3 AM Tue 38 38 SE 14 4642 6900 0 Blue 0
4 AM Tue 38 38 SE 17 4642 6900 0 Blue 0
5 AM Tue 37 37 SE 17 4633 6900 0 Blue 0
6 AM Tue 37 37 SE 17 4633 6900 0 Blue 0
7 AM Tue 37 37 SE 17 4633 6900 0 Blue 0
8 AM Tue 37 37 SE 17 4633 6900 0 Blue 0
9 AM Tue 37 37 SE 17 4633 6900 0 Blue 0
10 AM Tue 38 38 SE 13 4642 6900 0 Blue 0
11 AM Tue 38 38 SE 13 4642 6900 0 Blue 0
12 Noon Tue 38 38 SE 13 4642 6900 0 Blue 0
1 PM Tue 37 37 SE 13 4633 6900 0 Blue 0
2 PM Tue 37 37 SE 13 4633 6900 0 Blue 0
3 PM Tue 36 36 SE 13 4633 6900 0 Blue 0
4 PM Tue 35 35 E 2 4633 6900 0 Blue 0
5 PM Tue 34 34 E 2 4633 6900 0 Blue 0
6 PM Tue 33 33 E 2 4633 6900 0 Blue 0
7 PM Tue 32 32 E 2 4633 6900 0 Blue 0
8 PM Tue 31 31 E 2 4633 6900 0 Blue 0
9 PM Tue 31 31 E 2 4633 6900 0 Blue 0
10 PM Tue 30 30 NE 3 4633 6900 0 Blue 0
11 PM Tue 30 30 NE 3 4633 6900 0 Blue 0
12 Midnight Wed 31 31 NE 3 4633 6900 0 Blue 0
1 AM Wed 31 31 NE 3 4633 6900 0 Blue 0
2 AM Wed 32 32 NE 3 4633 6900 0 Blue 0
3 AM Wed 33 33 NE 3 4633 6900 0 Blue 0
4 AM Wed 34 34 N 3 4633 6900 0 Blue 0
5 AM Wed 35 35 N 3 4633 6900 0 Blue 0
6 AM Wed 36 36 N 3 4633 6900 0 Blue 0
7 AM Wed 37 37 N 3 4633 6900 0 Blue 0
8 AM Wed 38 38 N 3 4642 6900 0 Blue 0
9 AM Wed 39 39 N 3 4828 6900 0 Blue 0
10 AM Wed 41 42 N 5 5385 6900 0 Blue 0
11 AM Wed 42 43 N 5 5570 6900 0 Blue 0
12 Noon Wed 44 45 N 5 5939 6900 0 Blue 0
1 PM Wed 46 47 N 5 6343 6900 0 Blue 1
2 PM Wed 48 49 N 5 6633 6900 0 Blue 3
3 PM Wed 49 49 N 5 6633 6900 0 Blue 3
4 PM Wed 49 49 NW 1 6633 6900 0 Blue 3
5 PM Wed 48 48 NW 1 6532 6900 0 Blue 2
6 PM Wed 47 47 NW 1 6343 6900 0 Blue 1
7 PM Wed 45 45 NW 1 5939 6900 0 Blue 0
8 PM Wed 42 42 NW 1 5385 6900 0 Blue 0
9 PM Wed 40 40 NW 1 5014 6900 0 Blue 0
10 PM Wed 39 39 NE 2 4828 6900 0 Blue 0
11 PM Wed 38 38 NE 2 4642 6900 0 Blue 0
12 Midnight Thu 38 38 NE 2 4642 6900 0 Blue 0
1 AM Thu 38 38 NE 2 4642 6900 0 Blue 0
2 AM Thu 38 38 NE 2 4642 6900 0 Blue 0
3 AM Thu 39 39 NE 2 4828 6900 0 Blue 0
4 AM Thu 40 40 N 5 5014 6900 0 Blue 0
5 AM Thu 42 42 N 5 5385 6900 0 Blue 0
6 AM Thu 44 44 N 5 5755 6900 0 Blue 0
7 AM Thu 47 47 N 5 6343 6900 0 Blue 1
8 AM Thu 49 49 N 5 6633 6900 0 Blue 3
9 AM Thu 51 51 N 5 6838 6900 0 Blue 5
10 AM Thu 52 53 NE 2 7129 6900 0 Blue 7
11 AM Thu 53 55 NE 2 7419 6975 75 Blue 9
12 Noon Thu 53 55 NE 2 7419 6975 75 Blue 9
1 PM Thu 53 55 NE 2 7419 6975 75 Blue 9
2 PM Thu 53 54 NE 2 7274 6900 0 Blue 8
3 PM Thu 52 53 NE 2 7129 6900 0 Blue 7
4 PM Thu 50 50 SW 1 6735 6900 0 Blue 4
5 PM Thu 49 49 SW 1 6633 6900 0 Blue 3
6 PM Thu 47 47 SW 1 6343 6900 0 Blue 1
7 PM Thu 45 45 SW 1 5939 6900 0 Blue 0
8 PM Thu 43 43 SW 1 5570 6900 0 Blue 0
9 PM Thu 41 41 SW 1 5200 6900 0 Blue 0
10 PM Thu 39 39 SE 3 4828 6900 0 Blue 0
11 PM Thu 38 38 SE 3 4642 6900 0 Blue 0
12 Midnight Fri 37 37 SE 3 4633 6900 0 Blue 0
1 AM Fri 36 36 SE 3 4633 6900 0 Blue 0
2 AM Fri 36 36 SE 3 4633 6900 0 Blue 0
3 AM Fri 36 36 SE 3 4633 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