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

Station:

KVBG

Date/Time:

18 AUG 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)
5 AM Sat 50 50 E 3 9770 10973 0 Blue 0
6 AM Sat 53 53 E 3 9770 10973 0 Blue 0
7 AM Sat 56 56 E 3 11188 10973 0 Blue 1
8 AM Sat 58 59 E 3 12979 11160 187 Blue 4
9 AM Sat 61 63 E 3 14492 13218 2245 Blue 8
10 AM Sat 62 66 E 3 15665 14434 3461 Blue 11
11 AM Sat 64 69 E 5 16576 15594 4621 White 14
12 Noon Sat 64 71 E 5 17013 16340 5367 White 16
1 PM Sat 65 72 E 5 17232 16706 5733 White 17
2 PM Sat 66 73 SW 6 17450 17059 6086 White 18
3 PM Sat 67 73 SW 6 17450 17059 6086 White 18
4 PM Sat 68 72 SW 6 17232 16706 5733 White 17
5 PM Sat 68 70 W 7 16794 15969 4996 White 15
6 PM Sat 67 68 W 7 16356 15213 4240 White 13
7 PM Sat 65 65 W 7 15280 14035 3062 Blue 10
8 PM Sat 62 62 N 8 14089 12956 1983 Blue 7
9 PM Sat 60 60 N 8 13263 11835 862 Blue 5
10 PM Sat 58 58 N 8 12531 10973 0 Blue 3
11 PM Sat 57 57 NE 7 11876 10973 0 Blue 2
12 Midnight Sun 56 56 NE 7 11188 10973 0 Blue 1
1 AM Sun 55 55 NE 7 10448 10973 0 Blue 0
2 AM Sun 53 53 NE 7 9770 10973 0 Blue 0
3 AM Sun 52 52 NE 7 9770 10973 0 Blue 0
4 AM Sun 50 50 NE 7 9770 10973 0 Blue 0
5 AM Sun 50 50 SE 6 9770 10973 0 Blue 0
6 AM Sun 52 52 SE 6 9770 10973 0 Blue 0
7 AM Sun 56 56 SE 6 11188 10973 0 Blue 1
8 AM Sun 59 60 SE 6 13263 11835 862 Blue 5
9 AM Sun 62 64 SE 6 14889 13630 2657 Blue 9
10 AM Sun 63 67 SE 6 16044 14826 3853 Blue 12
11 AM Sun 64 69 S 8 16576 15594 4621 White 14
12 Noon Sun 65 71 S 8 17013 16340 5367 White 16
1 PM Sun 65 72 S 8 17232 16706 5733 White 17
2 PM Sun 66 72 SW 10 17232 16706 5733 White 17
3 PM Sun 66 71 SW 10 17013 16340 5367 White 16
4 PM Sun 67 71 SW 10 17013 16340 5367 White 16
5 PM Sun 67 69 SW 13 16576 15594 4621 White 14
6 PM Sun 65 65 SW 13 15280 14035 3062 Blue 10
7 PM Sun 63 63 SW 13 14492 13218 2245 Blue 8
8 PM Sun 61 61 SW 13 13680 12478 1505 Blue 6
9 PM Sun 59 59 SW 13 12979 11160 187 Blue 4
10 PM Sun 58 58 SW 13 12531 10973 0 Blue 3
11 PM Sun 57 57 SW 7 11876 10973 0 Blue 2
12 Midnight Mon 56 56 SW 7 11188 10973 0 Blue 1
1 AM Mon 55 55 SW 7 10448 10973 0 Blue 0
2 AM Mon 53 53 SW 7 9770 10973 0 Blue 0
3 AM Mon 52 52 SW 7 9770 10973 0 Blue 0
4 AM Mon 50 50 SW 7 9770 10973 0 Blue 0
5 AM Mon 50 50 SW 8 9770 10973 0 Blue 0
6 AM Mon 52 52 SW 8 9770 10973 0 Blue 0
7 AM Mon 56 56 SW 8 11188 10973 0 Blue 1
8 AM Mon 59 59 SW 8 12979 11160 187 Blue 4
9 AM Mon 62 64 SW 8 14889 13630 2657 Blue 9
10 AM Mon 64 68 SW 8 16356 15213 4240 White 13
11 AM Mon 65 70 SW 16 16794 15969 4996 White 15
12 Noon Mon 65 71 SW 16 17013 16340 5367 White 16
1 PM Mon 64 70 SW 16 16794 15969 4996 White 15
2 PM Mon 65 71 SW 16 17013 16340 5367 White 16
3 PM Mon 65 70 SW 16 16794 15969 4996 White 15
4 PM Mon 66 69 SW 16 16576 15594 4621 White 14
5 PM Mon 66 68 SW 16 16356 15213 4240 White 13
6 PM Mon 64 65 SW 16 15280 14035 3062 Blue 10
7 PM Mon 62 62 SW 16 14089 12956 1983 Blue 7
8 PM Mon 60 60 SW 16 13263 11835 862 Blue 5
9 PM Mon 58 58 SW 16 12531 10973 0 Blue 3
10 PM Mon 56 56 SW 16 11188 10973 0 Blue 1
11 PM Mon 55 55 S 10 10448 10973 0 Blue 0
12 Midnight Tue 54 54 S 10 9883 10973 0 Blue 0
1 AM Tue 53 53 S 10 9770 10973 0 Blue 0
2 AM Tue 52 52 S 10 9770 10973 0 Blue 0
3 AM Tue 51 51 S 10 9770 10973 0 Blue 0
4 AM Tue 51 51 S 10 9770 10973 0 Blue 0
5 AM Tue 51 51 SW 9 9770 10973 0 Blue 0
6 AM Tue 53 53 SW 9 9770 10973 0 Blue 0
7 AM Tue 56 56 SW 9 11188 10973 0 Blue 1
8 AM Tue 58 58 SW 9 12531 10973 0 Blue 3
9 AM Tue 60 62 SW 9 14089 12956 1983 Blue 7
10 AM Tue 61 65 SW 9 15280 14035 3062 Blue 10
11 AM Tue 63 68 S 13 16356 15213 4240 White 13
12 Noon Tue 66 72 S 13 17232 16706 5733 White 17
1 PM Tue 68 75 S 13 17846 17361 6388 Blue 20
2 PM Tue 69 75 S 13 17846 17361 6388 Blue 20
3 PM Tue 68 73 S 13 17450 17059 6086 White 18
4 PM Tue 66 70 S 13 16794 15969 4996 White 15
5 PM Tue 63 65 S 14 15280 14035 3062 Blue 10
6 PM Tue 61 62 S 14 14089 12956 1983 Blue 7
7 PM Tue 59 59 S 14 12979 11160 187 Blue 4
8 PM Tue 58 58 S 14 12531 10973 0 Blue 3
9 PM Tue 57 57 S 14 11876 10973 0 Blue 2
10 PM Tue 56 56 S 14 11188 10973 0 Blue 1
11 PM Tue 55 55 S 10 10448 10973 0 Blue 0
12 Midnight Wed 54 54 S 10 9883 10973 0 Blue 0
1 AM Wed 54 54 S 10 9883 10973 0 Blue 0
2 AM Wed 53 53 S 10 9770 10973 0 Blue 0
3 AM Wed 52 52 S 10 9770 10973 0 Blue 0
4 AM Wed 51 51 S 10 9770 10973 0 Blue 0
5 AM Wed 51 51 S 9 9770 10973 0 Blue 0
6 AM Wed 53 53 S 9 9770 10973 0 Blue 0
7 AM Wed 55 55 S 9 10448 10973 0 Blue 0
8 AM Wed 58 58 S 9 12531 10973 0 Blue 3
9 AM Wed 60 62 S 9 14089 12956 1983 Blue 7
10 AM Wed 61 64 S 9 14889 13630 2657 Blue 9
11 AM Wed 63 68 S 12 16356 15213 4240 White 13
12 Noon Wed 65 71 S 12 17013 16340 5367 White 16
1 PM Wed 68 74 S 12 17665 17210 6237 White 19
2 PM Wed 69 75 S 12 17846 17361 6388 Blue 20
3 PM Wed 69 74 S 12 17665 17210 6237 White 19
4 PM Wed 67 71 S 12 17013 16340 5367 White 16
5 PM Wed 64 66 SW 10 15665 14434 3461 Blue 11
6 PM Wed 61 62 SW 10 14089 12956 1983 Blue 7
7 PM Wed 59 59 SW 10 12979 11160 187 Blue 4
8 PM Wed 57 57 SW 10 11876 10973 0 Blue 2
9 PM Wed 56 56 SW 10 11188 10973 0 Blue 1
10 PM Wed 56 56 SW 10 11188 10973 0 Blue 1
11 PM Wed 55 55 S 7 10448 10973 0 Blue 0
12 Midnight Thu 54 54 S 7 9883 10973 0 Blue 0
1 AM Thu 52 52 S 7 9770 10973 0 Blue 0
2 AM Thu 51 51 S 7 9770 10973 0 Blue 0
3 AM Thu 50 50 S 7 9770 10973 0 Blue 0
4 AM Thu 49 49 S 7 9770 10973 0 Blue 0
5 AM Thu 50 50 SW 7 9770 10973 0 Blue 0
6 AM Thu 52 52 SW 7 9770 10973 0 Blue 0
7 AM Thu 54 54 SW 7 9883 10973 0 Blue 0
8 AM Thu 57 57 SW 7 11876 10973 0 Blue 2
9 AM Thu 59 61 SW 7 13680 12478 1505 Blue 6
10 AM Thu 61 64 SW 7 14889 13630 2657 Blue 9
11 AM Thu 63 68 SW 9 16356 15213 4240 White 13
12 Noon Thu 66 72 SW 9 17232 16706 5733 White 17
1 PM Thu 68 74 SW 9 17665 17210 6237 White 19
2 PM Thu 69 75 SW 9 17846 17361 6388 Blue 20
3 PM Thu 68 73 SW 9 17450 17059 6086 White 18
4 PM Thu 66 69 SW 9 16576 15594 4621 White 14
5 PM Thu 63 65 SW 10 15280 14035 3062 Blue 10
6 PM Thu 61 62 SW 10 14089 12956 1983 Blue 7
7 PM Thu 59 59 SW 10 12979 11160 187 Blue 4
8 PM Thu 58 58 SW 10 12531 10973 0 Blue 3
9 PM Thu 57 57 SW 10 11876 10973 0 Blue 2
10 PM Thu 56 56 SW 10 11188 10973 0 Blue 1
11 PM Thu 56 56 SW 8 11188 10973 0 Blue 1
12 Midnight Fri 55 55 SW 8 10448 10973 0 Blue 0
1 AM Fri 53 53 SW 8 9770 10973 0 Blue 0
2 AM Fri 52 52 SW 8 9770 10973 0 Blue 0
3 AM Fri 51 51 SW 8 9770 10973 0 Blue 0
4 AM Fri 50 50 SW 8 9770 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