Detailed Predictions for: Walts
Launch Altitude (f): 9085
LZ Altitude (f): 3640
Sounding

Station:

KVBG

Date/Time:

17 SEP 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 45 45 NW 13 6673 9085 0 Blue 0
6 AM Tue 49 49 NW 12 6757 9085 0 Blue 0
7 AM Tue 45 45 NW 10 6673 9085 0 Blue 0
8 AM Tue 50 50 NW 9 6925 9085 0 Blue 0
9 AM Tue 52 53 N 9 7428 9085 0 Blue 0
10 AM Tue 54 57 NE 10 8303 9085 0 Blue 2
11 AM Tue 56 60 E 12 9636 9085 0 Blue 5
12 Noon Tue 59 64 E 13 12276 10102 1017 Blue 9
1 PM Tue 61 67 SE 14 13261 12173 3088 Blue 12
2 PM Tue 62 68 SE 15 13423 12786 3701 Blue 13
3 PM Tue 63 67 SE 16 13261 12173 3088 Blue 12
4 PM Tue 63 66 SE 17 13099 11506 2421 Blue 11
5 PM Tue 63 64 SE 17 12276 10102 1017 Blue 9
6 PM Tue 61 61 SE 16 10146 9085 0 Blue 6
7 PM Tue 57 57 S 14 8303 9085 0 Blue 2
8 PM Tue 54 54 S 12 7596 9085 0 Blue 0
9 PM Tue 53 53 S 10 7428 9085 0 Blue 0
10 PM Tue 53 53 SW 9 7428 9085 0 Blue 0
11 PM Tue 52 52 W 9 7261 9085 0 Blue 0
12 Midnight Wed 51 51 W 9 7093 9085 0 Blue 0
1 AM Wed 52 52 W 10 7261 9085 0 Blue 0
2 AM Wed 52 52 W 10 7261 9085 0 Blue 0
3 AM Wed 51 51 W 10 7093 9085 0 Blue 0
4 AM Wed 50 50 W 12 6925 9085 0 Blue 0
5 AM Wed 50 50 W 12 6925 9085 0 Blue 0
6 AM Wed 48 48 W 10 6673 9085 0 Blue 0
7 AM Wed 49 49 W 10 6757 9085 0 Blue 0
8 AM Wed 54 54 W 9 7596 9085 0 Blue 0
9 AM Wed 57 58 SW 9 8582 9085 0 Blue 3
10 AM Wed 59 62 S 8 10884 9085 0 Blue 7
11 AM Wed 61 66 SE 9 13099 11506 2421 Blue 11
12 Noon Wed 64 70 SE 12 13755 13230 4145 Blue 15
1 PM Wed 65 71 SE 13 14053 13391 4306 Blue 16
2 PM Wed 66 72 SE 15 14467 13552 4467 Blue 17
3 PM Wed 67 71 S 15 14053 13391 4306 Blue 16
4 PM Wed 67 70 SW 15 13755 13230 4145 Blue 15
5 PM Wed 65 66 SW 15 13099 11506 2421 Blue 11
6 PM Wed 62 62 SW 16 10884 9085 0 Blue 7
7 PM Wed 57 57 W 17 8303 9085 0 Blue 2
8 PM Wed 53 53 W 18 7428 9085 0 Blue 0
9 PM Wed 51 51 W 17 7093 9085 0 Blue 0
10 PM Wed 50 50 W 16 6925 9085 0 Blue 0
11 PM Wed 50 50 W 15 6925 9085 0 Blue 0
12 Midnight Thu 50 50 W 15 6925 9085 0 Blue 0
1 AM Thu 49 49 W 14 6757 9085 0 Blue 0
2 AM Thu 48 48 W 14 6673 9085 0 Blue 0
3 AM Thu 47 47 W 14 6673 9085 0 Blue 0
4 AM Thu 46 46 W 13 6673 9085 0 Blue 0
5 AM Thu 46 46 W 13 6673 9085 0 Blue 0
6 AM Thu 47 47 W 12 6673 9085 0 Blue 0
7 AM Thu 48 48 W 10 6673 9085 0 Blue 0
8 AM Thu 50 50 W 9 6925 9085 0 Blue 0
9 AM Thu 52 53 SW 9 7428 9085 0 Blue 0
10 AM Thu 54 57 SE 10 8303 9085 0 Blue 2
11 AM Thu 56 61 E 12 10146 9085 0 Blue 6
12 Noon Thu 57 63 SE 12 11599 9600 515 Blue 8
1 PM Thu 59 65 SW 13 12892 10803 1718 Blue 10
2 PM Thu 60 66 W 13 13099 11506 2421 Blue 11
3 PM Thu 61 65 W 13 12892 10803 1718 Blue 10
4 PM Thu 61 64 W 13 12276 10102 1017 Blue 9
5 PM Thu 59 60 NW 13 9636 9085 0 Blue 5
6 PM Thu 56 56 NW 14 8023 9085 0 Blue 1
7 PM Thu 52 52 N 15 7261 9085 0 Blue 0
8 PM Thu 49 49 N 15 6757 9085 0 Blue 0
9 PM Thu 47 47 N 15 6673 9085 0 Blue 0
10 PM Thu 46 46 NW 14 6673 9085 0 Blue 0
11 PM Thu 45 45 NW 13 6673 9085 0 Blue 0
12 Midnight Fri 45 45 NW 13 6673 9085 0 Blue 0
1 AM Fri 46 46 NW 13 6673 9085 0 Blue 0
2 AM Fri 45 45 NW 13 6673 9085 0 Blue 0
3 AM Fri 44 44 NW 13 6673 9085 0 Blue 0
4 AM Fri 43 43 NW 13 6673 9085 0 Blue 0
5 AM Fri 43 43 NW 13 6673 9085 0 Blue 0
6 AM Fri 44 44 NW 12 6673 9085 0 Blue 0
7 AM Fri 46 46 N 12 6673 9085 0 Blue 0
8 AM Fri 48 48 N 10 6673 9085 0 Blue 0
9 AM Fri 50 51 N 9 7093 9085 0 Blue 0
10 AM Fri 52 55 NE 9 7763 9085 0 Blue 0
11 AM Fri 54 59 NE 9 9113 9085 0 Blue 4
12 Noon Fri 55 61 NE 12 10146 9085 0 Blue 6
1 PM Fri 57 63 E 13 11599 9600 515 Blue 8
2 PM Fri 59 65 E 15 12892 10803 1718 Blue 10
3 PM Fri 60 64 E 15 12276 10102 1017 Blue 9
4 PM Fri 61 64 SE 15 12276 10102 1017 Blue 9
5 PM Fri 60 61 SE 14 10146 9085 0 Blue 6
6 PM Fri 57 57 SE 14 8303 9085 0 Blue 2
7 PM Fri 54 54 SE 14 7596 9085 0 Blue 0
8 PM Fri 50 50 SE 14 6925 9085 0 Blue 0
9 PM Fri 49 49 S 13 6757 9085 0 Blue 0
10 PM Fri 48 48 SW 12 6673 9085 0 Blue 0
11 PM Fri 48 48 W 10 6673 9085 0 Blue 0
12 Midnight Sat 48 48 W 10 6673 9085 0 Blue 0
1 AM Sat 49 49 NW 10 6757 9085 0 Blue 0
2 AM Sat 48 48 NW 10 6673 9085 0 Blue 0
3 AM Sat 47 47 NW 10 6673 9085 0 Blue 0
4 AM Sat 46 46 NW 12 6673 9085 0 Blue 0
5 AM Sat 46 46 NW 12 6673 9085 0 Blue 0
6 AM Sat 47 47 NW 12 6673 9085 0 Blue 0
7 AM Sat 50 50 N 10 6925 9085 0 Blue 0
8 AM Sat 52 52 N 10 7261 9085 0 Blue 0
9 AM Sat 55 56 N 10 8023 9085 0 Blue 1
10 AM Sat 57 60 NE 12 9636 9085 0 Blue 5
11 AM Sat 59 64 E 13 12276 10102 1017 Blue 9
12 Noon Sat 60 66 E 14 13099 11506 2421 Blue 11
1 PM Sat 62 68 SE 15 13423 12786 3701 Blue 13
2 PM Sat 64 69 SE 16 13585 13068 3983 Blue 14
3 PM Sat 65 69 SE 16 13585 13068 3983 Blue 14
4 PM Sat 65 68 SE 16 13423 12786 3701 Blue 13
5 PM Sat 64 65 SE 16 12892 10803 1718 Blue 10
6 PM Sat 61 61 SE 16 10146 9085 0 Blue 6
7 PM Sat 57 57 SE 15 8303 9085 0 Blue 2
8 PM Sat 53 53 SE 14 7428 9085 0 Blue 0
9 PM Sat 51 51 S 13 7093 9085 0 Blue 0
10 PM Sat 50 50 SW 12 6925 9085 0 Blue 0
11 PM Sat 50 50 W 10 6925 9085 0 Blue 0
12 Midnight Sun 49 49 W 10 6757 9085 0 Blue 0
1 AM Sun 49 49 W 10 6757 9085 0 Blue 0
2 AM Sun 48 48 W 10 6673 9085 0 Blue 0
3 AM Sun 48 48 W 10 6673 9085 0 Blue 0
4 AM Sun 48 48 W 12 6673 9085 0 Blue 0
5 AM Sun 48 48 W 12 6673 9085 0 Blue 0
6 AM Sun 50 50 W 12 6925 9085 0 Blue 0
7 AM Sun 52 52 W 10 7261 9085 0 Blue 0
8 AM Sun 54 54 W 10 7596 9085 0 Blue 0
9 AM Sun 57 58 SW 12 8582 9085 0 Blue 3
10 AM Sun 59 62 S 13 10884 9085 0 Blue 7
11 AM Sun 62 66 SE 15 13099 11506 2421 Blue 11
12 Noon Sun 64 69 S 17 13585 13068 3983 Blue 14
1 PM Sun 66 71 S 21 14053 13391 4306 Blue 16
2 PM Sun 67 72 S 22 14467 13552 4467 Blue 17
3 PM Sun 68 72 S 22 14467 13552 4467 Blue 17
4 PM Sun 68 70 S 21 13755 13230 4145 Blue 15
5 PM Sun 66 67 S 20 13261 12173 3088 Blue 12
6 PM Sun 63 63 S 20 11599 9600 515 Blue 8
7 PM Sun 59 59 SW 18 9113 9085 0 Blue 4
8 PM Sun 55 55 W 18 7763 9085 0 Blue 0
9 PM Sun 53 53 W 17 7428 9085 0 Blue 0
10 PM Sun 53 53 W 16 7428 9085 0 Blue 0
11 PM Sun 53 53 W 15 7428 9085 0 Blue 0
12 Midnight Mon 53 53 W 15 7428 9085 0 Blue 0
1 AM Mon 53 53 W 15 7428 9085 0 Blue 0
2 AM Mon 52 52 W 15 7261 9085 0 Blue 0
3 AM Mon 51 51 W 16 7093 9085 0 Blue 0
4 AM Mon 51 51 W 17 7093 9085 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