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

Station:

KVBG

Date/Time:

12Z 23 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 Sat 31 31 NW 17 7001 9085 0 Blue 0
6 AM Sat 30 30 NW 17 7001 9085 0 Blue 0
7 AM Sat 30 30 NW 17 7001 9085 0 Blue 0
8 AM Sat 35 35 NW 18 7001 9085 0 Blue 0
9 AM Sat 38 39 N 20 8256 9085 0 Blue 3
10 AM Sat 40 42 N 21 8877 9085 0 Blue 6
11 AM Sat 48 51 N 20 11134 10500 1415 Blue 15
12 Noon Sat 49 53 N 18 11526 10924 1839 Blue 17
1 PM Sat 50 54 N 17 11722 11109 2024 Blue 18
2 PM Sat 51 55 N 16 11917 11305 2220 Blue 19
3 PM Sat 52 55 N 15 11917 11305 2220 Blue 19
4 PM Sat 52 54 N 15 11722 11109 2024 Blue 18
5 PM Sat 44 44 N 16 9310 9085 0 Blue 8
6 PM Sat 43 43 N 16 9089 9085 0 Blue 7
7 PM Sat 41 41 NW 16 8670 9085 0 Blue 5
8 PM Sat 39 39 NW 17 8256 9085 0 Blue 3
9 PM Sat 37 37 NW 20 7843 9085 0 Blue 1
10 PM Sat 36 36 NW 22 7460 9085 0 Blue 0
11 PM Sat 35 35 NW 20 7001 9085 0 Blue 0
12 Midnight Sun 34 34 NW 21 7001 9085 0 Blue 0
1 AM Sun 35 35 NW 18 7001 9085 0 Blue 0
2 AM Sun 34 34 NW 16 7001 9085 0 Blue 0
3 AM Sun 34 34 NW 15 7001 9085 0 Blue 0
4 AM Sun 33 33 NW 13 7001 9085 0 Blue 0
5 AM Sun 33 33 NW 12 7001 9085 0 Blue 0
6 AM Sun 32 32 NW 13 7001 9085 0 Blue 0
7 AM Sun 32 32 NW 14 7001 9085 0 Blue 0
8 AM Sun 38 38 NW 14 8048 9085 0 Blue 2
9 AM Sun 42 43 N 13 9089 9085 0 Blue 7
10 AM Sun 45 48 N 12 10522 9553 468 Blue 12
11 AM Sun 55 59 N 10 13323 12075 2990 Blue 23
12 Noon Sun 57 62 N 10 15137 13206 4121 Blue 26
1 PM Sun 59 64 N 10 16076 14383 5298 White 28
2 PM Sun 60 65 N 10 16291 14983 5898 White 29
3 PM Sun 60 64 N 10 16076 14383 5298 White 28
4 PM Sun 61 63 N 9 15705 13784 4699 Blue 27
5 PM Sun 51 52 N 9 11330 10716 1631 Blue 16
6 PM Sun 50 50 N 9 10944 10282 1197 Blue 14
7 PM Sun 46 46 N 10 10084 9085 0 Blue 10
8 PM Sun 44 44 N 12 9310 9085 0 Blue 8
9 PM Sun 42 42 N 13 8877 9085 0 Blue 6
10 PM Sun 40 40 N 14 8463 9085 0 Blue 4
11 PM Sun 39 39 N 15 8256 9085 0 Blue 3
12 Midnight Mon 38 38 N 15 8048 9085 0 Blue 2
1 AM Mon 39 39 N 15 8256 9085 0 Blue 3
2 AM Mon 38 38 N 15 8048 9085 0 Blue 2
3 AM Mon 37 37 N 15 7843 9085 0 Blue 1
4 AM Mon 37 37 NW 15 7843 9085 0 Blue 1
5 AM Mon 36 36 NW 15 7460 9085 0 Blue 0
6 AM Mon 35 35 NW 14 7001 9085 0 Blue 0
7 AM Mon 35 35 NW 14 7001 9085 0 Blue 0
8 AM Mon 41 41 N 13 8670 9085 0 Blue 5
9 AM Mon 44 45 N 13 9593 9085 0 Blue 9
10 AM Mon 47 49 N 14 10741 10064 979 Blue 13
11 AM Mon 57 61 N 14 14530 12597 3512 Blue 25
12 Noon Mon 58 63 N 14 15705 13784 4699 Blue 27
1 PM Mon 60 65 N 14 16291 14983 5898 White 29
2 PM Mon 61 66 N 14 16506 15559 6474 White 30
3 PM Mon 61 64 N 13 16076 14383 5298 White 28
4 PM Mon 62 64 N 13 16076 14383 5298 White 28
5 PM Mon 53 54 N 12 11722 11109 2024 Blue 18
6 PM Mon 52 52 N 10 11330 10716 1631 Blue 16
7 PM Mon 48 48 N 10 10522 9553 468 Blue 12
8 PM Mon 46 46 N 10 10084 9085 0 Blue 10
9 PM Mon 44 44 NW 10 9310 9085 0 Blue 8
10 PM Mon 42 42 NW 12 8877 9085 0 Blue 6
11 PM Mon 41 41 NW 12 8670 9085 0 Blue 5
12 Midnight Tue 41 41 NW 12 8670 9085 0 Blue 5
1 AM Tue 41 41 NW 13 8670 9085 0 Blue 5
2 AM Tue 41 41 NW 13 8670 9085 0 Blue 5
3 AM Tue 40 40 NW 13 8463 9085 0 Blue 4
4 AM Tue 40 40 NW 12 8463 9085 0 Blue 4
5 AM Tue 39 39 NW 12 8256 9085 0 Blue 3
6 AM Tue 38 38 NW 12 8048 9085 0 Blue 2
7 AM Tue 38 38 N 12 8048 9085 0 Blue 2
8 AM Tue 44 44 N 12 9310 9085 0 Blue 8
9 AM Tue 48 49 N 12 10741 10064 979 Blue 13
10 AM Tue 50 53 N 12 11526 10924 1839 Blue 17
11 AM Tue 60 64 N 12 16076 14383 5298 White 28
12 Noon Tue 62 67 NE 12 16719 16115 7030 White 31
1 PM Tue 64 70 NE 12 17343 17070 7985 White 34
2 PM Tue 65 70 NE 12 17343 17070 7985 White 34
3 PM Tue 65 69 NE 12 17136 16899 7814 White 33
4 PM Tue 66 68 NE 12 16928 16727 7642 White 32
5 PM Tue 57 58 NE 12 12708 11888 2803 Blue 22
6 PM Tue 56 56 NE 10 12104 11499 2414 Blue 20
7 PM Tue 52 52 N 9 11330 10716 1631 Blue 16
8 PM Tue 50 50 N 8 10944 10282 1197 Blue 14
9 PM Tue 48 48 N 7 10522 9553 468 Blue 12
10 PM Tue 46 46 N 6 10084 9085 0 Blue 10
11 PM Tue 45 45 N 5 9593 9085 0 Blue 9
12 Midnight Wed 45 45 N 5 9593 9085 0 Blue 9
1 AM Wed 45 45 NW 6 9593 9085 0 Blue 9
2 AM Wed 45 45 NW 6 9593 9085 0 Blue 9
3 AM Wed 44 44 NW 7 9310 9085 0 Blue 8
4 AM Wed 44 44 NW 8 9310 9085 0 Blue 8
5 AM Wed 43 43 NW 9 9089 9085 0 Blue 7
6 AM Wed 42 42 NW 10 8877 9085 0 Blue 6
7 AM Wed 42 42 N 10 8877 9085 0 Blue 6
8 AM Wed 48 48 N 12 10522 9553 468 Blue 12
9 AM Wed 51 52 N 12 11330 10716 1631 Blue 16
10 AM Wed 53 56 N 12 12104 11499 2414 Blue 20
11 AM Wed 63 67 N 12 16719 16115 7030 White 31
12 Noon Wed 64 69 N 12 17136 16899 7814 White 33
1 PM Wed 66 72 NE 10 17757 17413 8328 White 36
2 PM Wed 67 72 NE 10 17757 17413 8328 White 36
3 PM Wed 67 71 NE 9 17551 17242 8157 White 35
4 PM Wed 68 70 NE 9 17343 17070 7985 White 34
5 PM Wed 59 60 NE 8 13908 12255 3170 Blue 24
6 PM Wed 58 58 NE 8 12708 11888 2803 Blue 22
7 PM Wed 54 54 N 7 11722 11109 2024 Blue 18
8 PM Wed 52 52 N 7 11330 10716 1631 Blue 16
9 PM Wed 50 50 NW 7 10944 10282 1197 Blue 14
10 PM Wed 48 48 NW 7 10522 9553 468 Blue 12
11 PM Wed 47 47 NW 7 10303 9296 211 Blue 11
12 Midnight Thu 47 47 NW 7 10303 9296 211 Blue 11
1 AM Thu 47 47 NW 7 10303 9296 211 Blue 11
2 AM Thu 47 47 NW 7 10303 9296 211 Blue 11
3 AM Thu 46 46 NW 8 10084 9085 0 Blue 10
4 AM Thu 46 46 NW 8 10084 9085 0 Blue 10
5 AM Thu 45 45 NW 8 9593 9085 0 Blue 9
6 AM Thu 44 44 NW 8 9310 9085 0 Blue 8
7 AM Thu 44 44 N 8 9310 9085 0 Blue 8
8 AM Thu 50 50 N 8 10944 10282 1197 Blue 14
9 AM Thu 53 54 N 8 11722 11109 2024 Blue 18
10 AM Thu 55 58 NE 8 12708 11888 2803 Blue 22
11 AM Thu 65 69 NE 8 17136 16899 7814 White 33
12 Noon Thu 66 71 NE 8 17551 17242 8157 White 35
1 PM Thu 68 73 E 8 17962 17583 8498 White 37
2 PM Thu 69 74 E 8 18167 17802 8717 White 38
3 PM Thu 69 73 E 7 17962 17583 8498 White 37
4 PM Thu 70 72 E 7 17757 17413 8328 White 36
5 PM Thu 60 61 E 7 14530 12597 3512 Blue 25
6 PM Thu 59 59 E 7 13323 12075 2990 Blue 23
7 PM Thu 56 56 SE 6 12104 11499 2414 Blue 20
8 PM Thu 53 53 S 6 11526 10924 1839 Blue 17
9 PM Thu 51 51 SW 6 11134 10500 1415 Blue 15
10 PM Thu 50 50 W 6 10944 10282 1197 Blue 14
11 PM Thu 48 48 W 6 10522 9553 468 Blue 12
12 Midnight Fri 48 48 W 6 10522 9553 468 Blue 12
1 AM Fri 48 48 W 7 10522 9553 468 Blue 12
2 AM Fri 48 48 W 8 10522 9553 468 Blue 12
3 AM Fri 47 47 W 8 10303 9296 211 Blue 11
4 AM Fri 47 47 W 9 10303 9296 211 Blue 11

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