Detailed Predictions for: Mammoth
Launch Altitude (f): 10973
LZ Altitude (f): 7850
Sounding

Station:

KVBG

Date/Time:

21 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 Wed 49 49 N 3 5902 10973 0 Blue 0
6 AM Wed 51 51 N 3 5902 10973 0 Blue 0
7 AM Wed 54 54 N 3 5965 10973 0 Blue 0
8 AM Wed 56 56 NE 6 7648 10973 0 Blue 0
9 AM Wed 59 61 NE 6 11160 10973 0 Blue 1
10 AM Wed 62 65 NE 6 13588 11772 799 Blue 5
11 AM Wed 65 70 S 7 16001 14517 3544 Blue 10
12 Noon Wed 68 74 S 7 17746 16357 5384 Blue 14
1 PM Wed 70 77 S 7 19036 17640 6667 Blue 17
2 PM Wed 71 77 SW 9 19036 17640 6667 Blue 17
3 PM Wed 70 75 SW 9 18176 16793 5820 Blue 15
4 PM Wed 68 72 SW 9 16891 15458 4485 Blue 12
5 PM Wed 66 68 SW 14 15071 13529 2556 Blue 8
6 PM Wed 64 64 SW 14 13032 11133 160 Blue 4
7 PM Wed 62 62 SW 14 11810 10973 0 Blue 2
8 PM Wed 60 60 SW 7 10477 10973 0 Blue 0
9 PM Wed 58 58 SW 7 9129 10973 0 Blue 0
10 PM Wed 57 57 SW 7 8409 10973 0 Blue 0
11 PM Wed 56 56 SW 7 7648 10973 0 Blue 0
12 Midnight Thu 56 56 SW 7 7648 10973 0 Blue 0
1 AM Thu 55 55 SW 7 6837 10973 0 Blue 0
2 AM Thu 55 55 SW 5 6837 10973 0 Blue 0
3 AM Thu 53 53 SW 5 5902 10973 0 Blue 0
4 AM Thu 52 52 SW 5 5902 10973 0 Blue 0
5 AM Thu 51 51 NE 8 5902 10973 0 Blue 0
6 AM Thu 53 53 NE 8 5902 10973 0 Blue 0
7 AM Thu 56 56 NE 8 7648 10973 0 Blue 0
8 AM Thu 59 59 W 9 9815 10973 0 Blue 0
9 AM Thu 62 63 W 9 12433 10973 0 Blue 3
10 AM Thu 64 67 W 9 14590 12975 2002 Blue 7
11 AM Thu 67 72 SW 9 16891 15458 4485 Blue 12
12 Noon Thu 70 76 SW 9 18610 17220 6247 Blue 16
1 PM Thu 73 80 SW 9 20738 18911 7938 Blue 20
2 PM Thu 75 81 SW 10 21318 19325 8352 Blue 21
3 PM Thu 75 80 SW 10 20738 18911 7938 Blue 20
4 PM Thu 74 78 SW 10 19492 18059 7086 Blue 18
5 PM Thu 71 73 NW 10 17323 15912 4939 Blue 13
6 PM Thu 68 69 NW 10 15541 14030 3057 Blue 9
7 PM Thu 65 65 NW 10 13588 11772 799 Blue 5
8 PM Thu 62 62 NW 10 11810 10973 0 Blue 2
9 PM Thu 60 60 NW 10 10477 10973 0 Blue 0
10 PM Thu 59 59 NW 10 9815 10973 0 Blue 0
11 PM Thu 58 58 NE 7 9129 10973 0 Blue 0
12 Midnight Fri 58 58 NE 7 9129 10973 0 Blue 0
1 AM Fri 58 58 NE 7 9129 10973 0 Blue 0
2 AM Fri 57 57 NE 7 8409 10973 0 Blue 0
3 AM Fri 55 55 NE 7 6837 10973 0 Blue 0
4 AM Fri 53 53 NE 7 5902 10973 0 Blue 0
5 AM Fri 52 52 E 7 5902 10973 0 Blue 0
6 AM Fri 52 52 E 7 5902 10973 0 Blue 0
7 AM Fri 54 54 E 7 5965 10973 0 Blue 0
8 AM Fri 57 57 E 7 8409 10973 0 Blue 0
9 AM Fri 59 61 E 7 11160 10973 0 Blue 1
10 AM Fri 61 64 E 7 13032 11133 160 Blue 4
11 AM Fri 63 68 SW 12 15071 13529 2556 Blue 8
12 Noon Fri 66 72 SW 12 16891 15458 4485 Blue 12
1 PM Fri 69 76 SW 12 18610 17220 6247 Blue 16
2 PM Fri 71 77 SW 12 19036 17640 6667 Blue 17
3 PM Fri 71 76 SW 12 18610 17220 6247 Blue 16
4 PM Fri 70 74 SW 12 17746 16357 5384 Blue 14
5 PM Fri 67 69 SW 13 15541 14030 3057 Blue 9
6 PM Fri 64 64 SW 13 13032 11133 160 Blue 4
7 PM Fri 60 60 SW 13 10477 10973 0 Blue 0
8 PM Fri 58 58 SW 13 9129 10973 0 Blue 0
9 PM Fri 56 56 SW 13 7648 10973 0 Blue 0
10 PM Fri 56 56 SW 13 7648 10973 0 Blue 0
11 PM Fri 56 56 S 8 7648 10973 0 Blue 0
12 Midnight Sat 56 56 S 8 7648 10973 0 Blue 0
1 AM Sat 56 56 S 8 7648 10973 0 Blue 0
2 AM Sat 55 55 S 8 6837 10973 0 Blue 0
3 AM Sat 54 54 S 8 5965 10973 0 Blue 0
4 AM Sat 53 53 S 8 5902 10973 0 Blue 0
5 AM Sat 52 52 S 6 5902 10973 0 Blue 0
6 AM Sat 53 53 S 6 5902 10973 0 Blue 0
7 AM Sat 55 55 S 6 6837 10973 0 Blue 0
8 AM Sat 57 57 S 6 8409 10973 0 Blue 0
9 AM Sat 60 62 S 6 11810 10973 0 Blue 2
10 AM Sat 62 66 S 6 14096 12385 1412 Blue 6
11 AM Sat 64 69 SW 9 15541 14030 3057 Blue 9
12 Noon Sat 65 72 SW 9 16891 15458 4485 Blue 12
1 PM Sat 66 73 SW 9 17323 15912 4939 Blue 13
2 PM Sat 66 73 SW 9 17323 15912 4939 Blue 13
3 PM Sat 67 73 SW 9 17323 15912 4939 Blue 13
4 PM Sat 68 72 SW 9 16891 15458 4485 Blue 12
5 PM Sat 66 68 SW 14 15071 13529 2556 Blue 8
6 PM Sat 63 64 SW 14 13032 11133 160 Blue 4
7 PM Sat 59 59 SW 14 9815 10973 0 Blue 0
8 PM Sat 56 56 SW 14 7648 10973 0 Blue 0
9 PM Sat 55 55 SW 14 6837 10973 0 Blue 0
10 PM Sat 55 55 SW 14 6837 10973 0 Blue 0
11 PM Sat 56 56 SW 6 7648 10973 0 Blue 0
12 Midnight Sun 56 56 SW 6 7648 10973 0 Blue 0
1 AM Sun 56 56 SW 6 7648 10973 0 Blue 0
2 AM Sun 55 55 SW 6 6837 10973 0 Blue 0
3 AM Sun 53 53 SW 6 5902 10973 0 Blue 0
4 AM Sun 52 52 SW 6 5902 10973 0 Blue 0
5 AM Sun 51 51 SW 6 5902 10973 0 Blue 0
6 AM Sun 52 52 SW 6 5902 10973 0 Blue 0
7 AM Sun 54 54 SW 6 5965 10973 0 Blue 0
8 AM Sun 56 56 SW 6 7648 10973 0 Blue 0
9 AM Sun 59 61 SW 6 11160 10973 0 Blue 1
10 AM Sun 62 66 SW 6 14096 12385 1412 Blue 6
11 AM Sun 64 70 SW 9 16001 14517 3544 Blue 10
12 Noon Sun 66 73 SW 9 17323 15912 4939 Blue 13
1 PM Sun 67 74 SW 9 17746 16357 5384 Blue 14
2 PM Sun 68 75 SW 9 18176 16793 5820 Blue 15
3 PM Sun 68 74 SW 9 17746 16357 5384 Blue 14
4 PM Sun 68 72 SW 9 16891 15458 4485 Blue 12
5 PM Sun 67 69 SW 14 15541 14030 3057 Blue 9
6 PM Sun 65 65 SW 14 13588 11772 799 Blue 5
7 PM Sun 62 62 SW 14 11810 10973 0 Blue 2
8 PM Sun 60 60 SW 14 10477 10973 0 Blue 0
9 PM Sun 58 58 SW 14 9129 10973 0 Blue 0
10 PM Sun 57 57 SW 14 8409 10973 0 Blue 0
11 PM Sun 56 56 SW 7 7648 10973 0 Blue 0
12 Midnight Mon 57 57 SW 7 8409 10973 0 Blue 0
1 AM Mon 58 58 SW 7 9129 10973 0 Blue 0
2 AM Mon 58 58 SW 7 9129 10973 0 Blue 0
3 AM Mon 55 55 SW 7 6837 10973 0 Blue 0
4 AM Mon 53 53 SW 7 5902 10973 0 Blue 0
5 AM Mon 51 51 SW 7 5902 10973 0 Blue 0
6 AM Mon 53 53 SW 7 5902 10973 0 Blue 0
7 AM Mon 56 56 SW 7 7648 10973 0 Blue 0
8 AM Mon 59 59 SW 7 9815 10973 0 Blue 0
9 AM Mon 61 63 SW 7 12433 10973 0 Blue 3
10 AM Mon 62 66 SW 7 14096 12385 1412 Blue 6
11 AM Mon 64 69 SW 7 15541 14030 3057 Blue 9
12 Noon Mon 66 72 SW 7 16891 15458 4485 Blue 12
1 PM Mon 68 75 SW 7 18176 16793 5820 Blue 15
2 PM Mon 69 75 SW 7 18176 16793 5820 Blue 15
3 PM Mon 69 74 SW 7 17746 16357 5384 Blue 14
4 PM Mon 68 72 SW 7 16891 15458 4485 Blue 12
5 PM Mon 67 69 SW 10 15541 14030 3057 Blue 9
6 PM Mon 64 64 SW 10 13032 11133 160 Blue 4
7 PM Mon 62 62 SW 10 11810 10973 0 Blue 2
8 PM Mon 59 59 SW 10 9815 10973 0 Blue 0
9 PM Mon 57 57 SW 10 8409 10973 0 Blue 0
10 PM Mon 56 56 SW 10 7648 10973 0 Blue 0
11 PM Mon 56 56 N 8 7648 10973 0 Blue 0
12 Midnight Tue 57 57 N 8 8409 10973 0 Blue 0
1 AM Tue 58 58 N 8 9129 10973 0 Blue 0
2 AM Tue 58 58 N 8 9129 10973 0 Blue 0
3 AM Tue 56 56 N 8 7648 10973 0 Blue 0
4 AM Tue 54 54 N 8 5965 10973 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