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

Station:

KMFR

Date/Time:

25 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 Mon 49 49 NE 9 5007 6900 0 Blue 0
6 AM Mon 50 50 NE 9 5007 6900 0 Blue 0
7 AM Mon 51 51 NE 9 5007 6900 0 Blue 0
8 AM Mon 53 53 NE 8 6587 6900 0 Blue 1
9 AM Mon 56 56 NE 8 8030 6900 0 Blue 4
10 AM Mon 58 59 NE 8 8676 7979 1079 Blue 7
11 AM Mon 61 64 NE 3 9611 8935 2035 Blue 12
12 Noon Mon 64 68 NE 3 11003 9764 2864 Blue 16
1 PM Mon 66 70 NE 3 11452 10729 3829 Blue 18
2 PM Mon 68 72 NW 2 12468 11117 4217 Blue 20
3 PM Mon 70 73 NW 2 13228 11372 4472 Blue 21
4 PM Mon 71 73 NW 2 13228 11372 4472 Blue 21
5 PM Mon 71 72 NW 7 12468 11117 4217 Blue 20
6 PM Mon 70 70 NW 7 11452 10729 3829 Blue 18
7 PM Mon 67 67 NW 7 10785 9586 2686 Blue 15
8 PM Mon 65 65 N 9 9790 9176 2276 Blue 13
9 PM Mon 62 62 N 9 9215 8661 1761 Blue 10
10 PM Mon 58 58 N 9 8539 7389 489 Blue 6
11 PM Mon 56 56 NE 12 8030 6900 0 Blue 4
12 Midnight Tue 53 53 NE 12 6587 6900 0 Blue 1
1 AM Tue 52 52 NE 12 6337 6900 0 Blue 0
2 AM Tue 51 51 E 8 5007 6900 0 Blue 0
3 AM Tue 50 50 E 8 5007 6900 0 Blue 0
4 AM Tue 50 50 E 8 5007 6900 0 Blue 0
5 AM Tue 51 51 NE 9 5007 6900 0 Blue 0
6 AM Tue 52 52 NE 9 6337 6900 0 Blue 0
7 AM Tue 53 53 NE 9 6587 6900 0 Blue 1
8 AM Tue 55 55 NE 10 7430 6900 0 Blue 3
9 AM Tue 57 58 NE 10 8539 7389 489 Blue 6
10 AM Tue 60 62 NE 10 9215 8661 1761 Blue 10
11 AM Tue 63 66 E 13 10058 9408 2508 Blue 14
12 Noon Tue 66 70 E 13 11452 10729 3829 Blue 18
1 PM Tue 69 74 E 13 13937 11742 4842 Blue 22
2 PM Tue 71 76 E 9 15045 13037 6137 White 24
3 PM Tue 73 77 E 9 15251 13741 6841 White 25
4 PM Tue 75 77 E 9 15251 13741 6841 White 25
5 PM Tue 75 76 E 10 15045 13037 6137 White 24
6 PM Tue 74 74 E 10 13937 11742 4842 Blue 22
7 PM Tue 72 72 E 10 12468 11117 4217 Blue 20
8 PM Tue 70 70 E 10 11452 10729 3829 Blue 18
9 PM Tue 67 67 E 10 10785 9586 2686 Blue 15
10 PM Tue 63 63 E 10 9432 8798 1898 Blue 11
11 PM Tue 60 60 E 15 8814 8388 1488 Blue 8
12 Midnight Wed 58 58 E 15 8539 7389 489 Blue 6
1 AM Wed 55 55 E 15 7430 6900 0 Blue 3
2 AM Wed 54 54 E 15 6806 6900 0 Blue 2
3 AM Wed 52 52 E 15 6337 6900 0 Blue 0
4 AM Wed 52 52 E 15 6337 6900 0 Blue 0
5 AM Wed 52 52 E 16 6337 6900 0 Blue 0
6 AM Wed 53 53 E 16 6587 6900 0 Blue 1
7 AM Wed 55 55 E 16 7430 6900 0 Blue 3
8 AM Wed 56 56 E 16 8030 6900 0 Blue 4
9 AM Wed 59 60 E 16 8814 8388 1488 Blue 8
10 AM Wed 61 63 E 16 9432 8798 1898 Blue 11
11 AM Wed 64 67 E 7 10785 9586 2686 Blue 15
12 Noon Wed 67 71 E 7 11820 10977 4077 Blue 19
1 PM Wed 70 74 E 7 13937 11742 4842 Blue 22
2 PM Wed 72 76 E 7 15045 13037 6137 White 24
3 PM Wed 74 77 E 7 15251 13741 6841 White 25
4 PM Wed 75 77 E 7 15251 13741 6841 White 25
5 PM Wed 75 76 E 6 15045 13037 6137 White 24
6 PM Wed 74 74 E 6 13937 11742 4842 Blue 22
7 PM Wed 72 72 E 6 12468 11117 4217 Blue 20
8 PM Wed 69 69 E 6 11144 9942 3042 Blue 17
9 PM Wed 66 66 E 6 10058 9408 2508 Blue 14
10 PM Wed 63 63 E 6 9432 8798 1898 Blue 11
11 PM Wed 61 61 SE 5 8951 8525 1625 Blue 9
12 Midnight Thu 58 58 SE 5 8539 7389 489 Blue 6
1 AM Thu 56 56 SE 5 8030 6900 0 Blue 4
2 AM Thu 55 55 SE 5 7430 6900 0 Blue 3
3 AM Thu 54 54 SE 5 6806 6900 0 Blue 2
4 AM Thu 54 54 SE 5 6806 6900 0 Blue 2
5 AM Thu 55 55 SE 5 7430 6900 0 Blue 3
6 AM Thu 56 56 SE 5 8030 6900 0 Blue 4
7 AM Thu 58 58 SE 5 8539 7389 489 Blue 6
8 AM Thu 60 60 SE 5 8814 8388 1488 Blue 8
9 AM Thu 63 63 SE 5 9432 8798 1898 Blue 11
10 AM Thu 66 68 SE 5 11003 9764 2864 Blue 16
11 AM Thu 68 71 SE 5 11820 10977 4077 Blue 19
12 Noon Thu 71 75 SE 5 14839 12284 5384 White 23
1 PM Thu 73 77 SE 5 15251 13741 6841 White 25
2 PM Thu 75 79 SE 5 15661 15661 8761 White 27
3 PM Thu 76 79 SE 5 15661 15661 8761 White 27
4 PM Thu 76 78 SE 5 15457 14834 7934 White 26
5 PM Thu 75 76 S 5 15045 13037 6137 White 24
6 PM Thu 74 74 S 5 13937 11742 4842 Blue 22
7 PM Thu 72 72 S 5 12468 11117 4217 Blue 20
8 PM Thu 69 69 S 5 11144 9942 3042 Blue 17
9 PM Thu 66 66 S 5 10058 9408 2508 Blue 14
10 PM Thu 63 63 S 5 9432 8798 1898 Blue 11
11 PM Thu 60 60 SW 2 8814 8388 1488 Blue 8
12 Midnight Fri 58 58 SW 2 8539 7389 489 Blue 6
1 AM Fri 57 57 SW 2 8402 6900 0 Blue 5
2 AM Fri 56 56 SW 2 8030 6900 0 Blue 4
3 AM Fri 55 55 SW 2 7430 6900 0 Blue 3
4 AM Fri 55 55 SW 2 7430 6900 0 Blue 3
5 AM Fri 56 56 E 3 8030 6900 0 Blue 4
6 AM Fri 57 57 E 3 8402 6900 0 Blue 5
7 AM Fri 58 58 E 3 8539 7389 489 Blue 6
8 AM Fri 60 60 E 3 8814 8388 1488 Blue 8
9 AM Fri 62 62 E 3 9215 8661 1761 Blue 10
10 AM Fri 64 65 E 3 9790 9176 2276 Blue 13
11 AM Fri 66 68 S 2 11003 9764 2864 Blue 16
12 Noon Fri 68 71 S 2 11820 10977 4077 Blue 19
1 PM Fri 70 74 S 2 13937 11742 4842 Blue 22
2 PM Fri 72 75 S 2 14839 12284 5384 White 23
3 PM Fri 73 76 S 2 15045 13037 6137 White 24
4 PM Fri 73 75 S 2 14839 12284 5384 White 23
5 PM Fri 72 73 SW 6 13228 11372 4472 Blue 21
6 PM Fri 71 71 SW 6 11820 10977 4077 Blue 19
7 PM Fri 69 69 SW 6 11144 9942 3042 Blue 17
8 PM Fri 67 67 SW 6 10785 9586 2686 Blue 15
9 PM Fri 65 65 SW 6 9790 9176 2276 Blue 13
10 PM Fri 62 62 SW 6 9215 8661 1761 Blue 10
11 PM Fri 60 60 W 3 8814 8388 1488 Blue 8
12 Midnight Sat 59 59 W 3 8676 7979 1079 Blue 7
1 AM Sat 57 57 W 3 8402 6900 0 Blue 5
2 AM Sat 56 56 W 3 8030 6900 0 Blue 4
3 AM Sat 56 56 W 3 8030 6900 0 Blue 4
4 AM Sat 56 56 W 3 8030 6900 0 Blue 4
5 AM Sat 57 57 NW 5 8402 6900 0 Blue 5
6 AM Sat 58 58 NW 5 8539 7389 489 Blue 6
7 AM Sat 59 59 NW 5 8676 7979 1079 Blue 7
8 AM Sat 61 61 NW 5 8951 8525 1625 Blue 9
9 AM Sat 63 63 NW 5 9432 8798 1898 Blue 11
10 AM Sat 65 67 NW 5 10785 9586 2686 Blue 15
11 AM Sat 67 70 N 3 11452 10729 3829 Blue 18
12 Noon Sat 69 73 N 3 13228 11372 4472 Blue 21
1 PM Sat 72 76 N 3 15045 13037 6137 White 24
2 PM Sat 73 77 N 3 15251 13741 6841 White 25
3 PM Sat 75 78 N 3 15457 14834 7934 White 26
4 PM Sat 75 77 N 3 15251 13741 6841 White 25
5 PM Sat 74 75 NW 5 14839 12284 5384 White 23
6 PM Sat 73 73 NW 5 13228 11372 4472 Blue 21
7 PM Sat 70 70 NW 5 11452 10729 3829 Blue 18
8 PM Sat 67 67 NW 5 10785 9586 2686 Blue 15
9 PM Sat 63 63 NW 5 9432 8798 1898 Blue 11
10 PM Sat 60 60 NW 5 8814 8388 1488 Blue 8
11 PM Sat 57 57 N 6 8402 6900 0 Blue 5
12 Midnight Sun 56 56 N 6 8030 6900 0 Blue 4
1 AM Sun 55 55 N 6 7430 6900 0 Blue 3
2 AM Sun 55 55 N 6 7430 6900 0 Blue 3
3 AM Sun 56 56 N 6 8030 6900 0 Blue 4
4 AM Sun 57 57 N 6 8402 6900 0 Blue 5

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