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

Station:

KMFR

Date/Time:

20 AUG 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 Tue 57 57 SE 6 4961 6900 0 Blue 0
6 AM Tue 58 58 SE 6 4961 6900 0 Blue 0
7 AM Tue 59 59 SE 6 4961 6900 0 Blue 0
8 AM Tue 60 60 SE 5 4961 6900 0 Blue 0
9 AM Tue 62 63 SE 5 5173 6900 0 Blue 0
10 AM Tue 64 67 SE 5 6673 6900 0 Blue 3
11 AM Tue 67 72 S 10 8438 8073 1173 Blue 8
12 Noon Tue 69 75 S 10 9524 8426 1526 Blue 11
1 PM Tue 71 78 S 10 11322 9490 2590 Blue 14
2 PM Tue 72 79 S 10 11859 10053 3153 Blue 15
3 PM Tue 73 79 S 10 11859 10053 3153 Blue 15
4 PM Tue 74 78 S 10 11322 9490 2590 Blue 14
5 PM Tue 74 76 SW 9 10160 8569 1669 Blue 12
6 PM Tue 73 74 SW 9 8882 8308 1408 Blue 10
7 PM Tue 72 72 SW 9 8438 8073 1173 Blue 8
8 PM Tue 70 70 W 8 8201 6900 0 Blue 6
9 PM Tue 68 68 W 8 7608 6900 0 Blue 4
10 PM Tue 66 66 W 8 6173 6900 0 Blue 2
11 PM Tue 64 64 W 6 5389 6900 0 Blue 0
12 Midnight Wed 62 62 W 6 4961 6900 0 Blue 0
1 AM Wed 61 61 W 6 4961 6900 0 Blue 0
2 AM Wed 60 60 W 6 4961 6900 0 Blue 0
3 AM Wed 59 59 W 6 4961 6900 0 Blue 0
4 AM Wed 59 59 W 6 4961 6900 0 Blue 0
5 AM Wed 59 59 NW 2 4961 6900 0 Blue 0
6 AM Wed 61 61 NW 2 4961 6900 0 Blue 0
7 AM Wed 62 62 NW 2 4961 6900 0 Blue 0
8 AM Wed 64 64 NW 3 5389 6900 0 Blue 0
9 AM Wed 67 68 NW 3 7608 6900 0 Blue 4
10 AM Wed 69 71 NW 3 8320 7545 645 Blue 7
11 AM Wed 71 73 W 8 8598 8191 1291 Blue 9
12 Noon Wed 72 75 W 8 9524 8426 1526 Blue 11
1 PM Wed 73 77 W 8 11179 8851 1951 Blue 13
2 PM Wed 74 77 W 10 11179 8851 1951 Blue 13
3 PM Wed 74 77 W 10 11179 8851 1951 Blue 13
4 PM Wed 74 76 W 10 10160 8569 1669 Blue 12
5 PM Wed 73 74 W 14 8882 8308 1408 Blue 10
6 PM Wed 72 72 W 14 8438 8073 1173 Blue 8
7 PM Wed 71 71 W 14 8320 7545 645 Blue 7
8 PM Wed 70 70 W 14 8201 6900 0 Blue 6
9 PM Wed 68 68 W 14 7608 6900 0 Blue 4
10 PM Wed 67 67 W 14 6673 6900 0 Blue 3
11 PM Wed 65 65 N 12 5824 6900 0 Blue 1
12 Midnight Thu 64 64 N 12 5389 6900 0 Blue 0
1 AM Thu 62 62 N 12 4961 6900 0 Blue 0
2 AM Thu 61 61 N 12 4961 6900 0 Blue 0
3 AM Thu 60 60 N 12 4961 6900 0 Blue 0
4 AM Thu 60 60 N 12 4961 6900 0 Blue 0
5 AM Thu 60 60 N 7 4961 6900 0 Blue 0
6 AM Thu 61 61 N 7 4961 6900 0 Blue 0
7 AM Thu 62 62 N 7 4961 6900 0 Blue 0
8 AM Thu 63 63 N 7 5173 6900 0 Blue 0
9 AM Thu 65 66 N 7 6173 6900 0 Blue 2
10 AM Thu 67 70 N 7 8201 6900 0 Blue 6
11 AM Thu 69 73 NW 3 8598 8191 1291 Blue 9
12 Noon Thu 71 77 NW 3 11179 8851 1951 Blue 13
1 PM Thu 74 80 NW 3 12773 11153 4253 Blue 16
2 PM Thu 76 82 NW 3 13203 11749 4849 Blue 18
3 PM Thu 78 83 NW 3 13408 12721 5821 Blue 19
4 PM Thu 79 83 NW 3 13408 12721 5821 Blue 19
5 PM Thu 79 81 NW 5 12988 11291 4391 Blue 17
6 PM Thu 78 79 NW 5 11859 10053 3153 Blue 15
7 PM Thu 77 77 NW 5 11179 8851 1951 Blue 13
8 PM Thu 75 75 NW 5 9524 8426 1526 Blue 11
9 PM Thu 73 73 NW 5 8598 8191 1291 Blue 9
10 PM Thu 70 70 NW 5 8201 6900 0 Blue 6
11 PM Thu 68 68 N 6 7608 6900 0 Blue 4
12 Midnight Fri 65 65 N 6 5824 6900 0 Blue 1
1 AM Fri 64 64 N 6 5389 6900 0 Blue 0
2 AM Fri 62 62 N 6 4961 6900 0 Blue 0
3 AM Fri 61 61 N 6 4961 6900 0 Blue 0
4 AM Fri 61 61 N 6 4961 6900 0 Blue 0
5 AM Fri 61 61 E 6 4961 6900 0 Blue 0
6 AM Fri 62 62 E 6 4961 6900 0 Blue 0
7 AM Fri 64 64 E 6 5389 6900 0 Blue 0
8 AM Fri 65 65 E 6 5824 6900 0 Blue 1
9 AM Fri 67 68 E 6 7608 6900 0 Blue 4
10 AM Fri 70 73 E 6 8598 8191 1291 Blue 9
11 AM Fri 72 77 S 8 11179 8851 1951 Blue 13
12 Noon Fri 74 80 S 8 12773 11153 4253 Blue 16
1 PM Fri 76 83 S 8 13408 12721 5821 Blue 19
2 PM Fri 77 84 S 8 14019 12935 6035 White 20
3 PM Fri 78 84 S 8 14019 12935 6035 White 20
4 PM Fri 79 83 S 8 13408 12721 5821 Blue 19
5 PM Fri 79 81 SW 8 12988 11291 4391 Blue 17
6 PM Fri 78 79 SW 8 11859 10053 3153 Blue 15
7 PM Fri 76 76 SW 8 10160 8569 1669 Blue 12
8 PM Fri 74 74 SW 8 8882 8308 1408 Blue 10
9 PM Fri 72 72 SW 8 8438 8073 1173 Blue 8
10 PM Fri 69 69 SW 8 8083 6900 0 Blue 5
11 PM Fri 67 67 NW 5 6673 6900 0 Blue 3
12 Midnight Sat 65 65 NW 5 5824 6900 0 Blue 1
1 AM Sat 63 63 NW 5 5173 6900 0 Blue 0
2 AM Sat 62 62 NW 5 4961 6900 0 Blue 0
3 AM Sat 61 61 NW 5 4961 6900 0 Blue 0
4 AM Sat 61 61 NW 5 4961 6900 0 Blue 0
5 AM Sat 61 61 NE 5 4961 6900 0 Blue 0
6 AM Sat 62 62 NE 5 4961 6900 0 Blue 0
7 AM Sat 64 64 NE 5 5389 6900 0 Blue 0
8 AM Sat 65 65 NE 5 5824 6900 0 Blue 1
9 AM Sat 68 69 NE 5 8083 6900 0 Blue 5
10 AM Sat 70 73 NE 5 8598 8191 1291 Blue 9
11 AM Sat 72 77 S 5 11179 8851 1951 Blue 13
12 Noon Sat 75 81 S 5 12988 11291 4391 Blue 17
1 PM Sat 77 84 S 5 14019 12935 6035 White 20
2 PM Sat 78 85 S 5 14229 13148 6248 White 21
3 PM Sat 79 85 S 5 14229 13148 6248 White 21
4 PM Sat 80 84 S 5 14019 12935 6035 White 20
5 PM Sat 80 83 W 9 13408 12721 5821 Blue 19
6 PM Sat 79 80 W 9 12773 11153 4253 Blue 16
7 PM Sat 77 77 W 9 11179 8851 1951 Blue 13
8 PM Sat 75 75 W 9 9524 8426 1526 Blue 11
9 PM Sat 73 73 W 9 8598 8191 1291 Blue 9
10 PM Sat 71 71 W 9 8320 7545 645 Blue 7
11 PM Sat 68 68 NW 5 7608 6900 0 Blue 4
12 Midnight Sun 66 66 NW 5 6173 6900 0 Blue 2
1 AM Sun 64 64 NW 5 5389 6900 0 Blue 0
2 AM Sun 63 63 NW 5 5173 6900 0 Blue 0
3 AM Sun 62 62 NW 5 4961 6900 0 Blue 0
4 AM Sun 61 61 NW 5 4961 6900 0 Blue 0
5 AM Sun 61 61 N 5 4961 6900 0 Blue 0
6 AM Sun 62 62 N 5 4961 6900 0 Blue 0
7 AM Sun 63 63 N 5 5173 6900 0 Blue 0
8 AM Sun 65 65 N 5 5824 6900 0 Blue 1
9 AM Sun 67 68 N 5 7608 6900 0 Blue 4
10 AM Sun 70 73 N 5 8598 8191 1291 Blue 9
11 AM Sun 72 77 S 3 11179 8851 1951 Blue 13
12 Noon Sun 74 80 S 3 12773 11153 4253 Blue 16
1 PM Sun 76 83 S 3 13408 12721 5821 Blue 19
2 PM Sun 78 85 S 3 14229 13148 6248 White 21
3 PM Sun 79 85 S 3 14229 13148 6248 White 21
4 PM Sun 80 84 S 3 14019 12935 6035 White 20
5 PM Sun 80 83 W 7 13408 12721 5821 Blue 19
6 PM Sun 79 80 W 7 12773 11153 4253 Blue 16
7 PM Sun 78 78 W 7 11322 9490 2590 Blue 14
8 PM Sun 76 76 W 7 10160 8569 1669 Blue 12
9 PM Sun 74 74 W 7 8882 8308 1408 Blue 10
10 PM Sun 72 72 W 7 8438 8073 1173 Blue 8
11 PM Sun 69 69 N 5 8083 6900 0 Blue 5
12 Midnight Mon 67 67 N 5 6673 6900 0 Blue 3
1 AM Mon 65 65 N 5 5824 6900 0 Blue 1
2 AM Mon 63 63 N 5 5173 6900 0 Blue 0
3 AM Mon 62 62 N 5 4961 6900 0 Blue 0
4 AM Mon 61 61 N 5 4961 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