Detailed Predictions for: McGee Creek
Launch Altitude (f): 9082
LZ Altitude (f): 7122
Sounding

Station:

KVBG

Date/Time:

25 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 Sun 53 53 W 5 9085 9085 3 Blue 0
6 AM Sun 55 55 W 5 9085 9085 3 Blue 0
7 AM Sun 58 58 W 5 10147 9085 3 Blue 1
8 AM Sun 62 62 N 5 11421 11132 2050 Blue 5
9 AM Sun 66 68 N 5 12961 11564 2482 Blue 11
10 AM Sun 70 73 N 5 14010 13354 4272 Blue 16
11 AM Sun 73 78 W 7 17019 14808 5726 Blue 21
12 Noon Sun 75 81 W 7 18715 16888 7806 White 24
1 PM Sun 77 84 W 7 19363 18373 9291 White 27
2 PM Sun 78 85 W 8 19574 18919 9837 White 28
3 PM Sun 78 83 W 8 19147 17884 8802 White 26
4 PM Sun 78 82 W 8 18931 17393 8311 White 25
5 PM Sun 77 79 W 13 17529 15616 6534 Blue 22
6 PM Sun 75 75 W 13 14964 13771 4689 Blue 18
7 PM Sun 72 72 W 13 13802 13145 4063 Blue 15
8 PM Sun 69 69 SW 12 13172 11664 2582 Blue 12
9 PM Sun 66 66 SW 12 11690 11467 2385 Blue 9
10 PM Sun 63 63 SW 12 11471 11318 2236 Blue 6
11 PM Sun 60 60 NW 5 11322 9085 3 Blue 3
12 Midnight Mon 58 58 NW 5 10147 9085 3 Blue 1
1 AM Mon 56 56 NW 5 9085 9085 3 Blue 0
2 AM Mon 54 54 NW 5 9085 9085 3 Blue 0
3 AM Mon 53 53 NW 5 9085 9085 3 Blue 0
4 AM Mon 52 52 NW 5 9085 9085 3 Blue 0
5 AM Mon 52 52 NW 3 9085 9085 3 Blue 0
6 AM Mon 54 54 NW 3 9085 9085 3 Blue 0
7 AM Mon 57 57 NW 3 9085 9085 3 Blue 0
8 AM Mon 60 60 S 3 11322 9085 3 Blue 3
9 AM Mon 65 67 S 3 12735 11516 2434 Blue 10
10 AM Mon 69 73 S 3 14010 13354 4272 Blue 16
11 AM Mon 73 78 E 7 17019 14808 5726 Blue 21
12 Noon Mon 75 81 E 7 18715 16888 7806 White 24
1 PM Mon 77 84 E 7 19363 18373 9291 White 27
2 PM Mon 78 84 E 8 19363 18373 9291 White 27
3 PM Mon 79 84 E 8 19363 18373 9291 White 27
4 PM Mon 80 84 E 8 19363 18373 9291 White 27
5 PM Mon 79 80 W 9 18025 16367 7285 Blue 23
6 PM Mon 77 77 W 9 16492 14185 5103 Blue 20
7 PM Mon 73 73 W 9 14010 13354 4272 Blue 16
8 PM Mon 70 70 W 9 13382 12627 3545 Blue 13
9 PM Mon 67 67 W 9 12735 11516 2434 Blue 10
10 PM Mon 64 64 W 9 11519 11368 2286 Blue 7
11 PM Mon 61 61 NW 7 11371 10132 1050 Blue 4
12 Midnight Tue 59 59 NW 7 11246 9085 3 Blue 2
1 AM Tue 57 57 NW 7 9085 9085 3 Blue 0
2 AM Tue 55 55 NW 7 9085 9085 3 Blue 0
3 AM Tue 54 54 NW 7 9085 9085 3 Blue 0
4 AM Tue 53 53 NW 7 9085 9085 3 Blue 0
5 AM Tue 53 53 N 5 9085 9085 3 Blue 0
6 AM Tue 55 55 N 5 9085 9085 3 Blue 0
7 AM Tue 58 58 N 5 10147 9085 3 Blue 1
8 AM Tue 62 62 N 5 11421 11132 2050 Blue 5
9 AM Tue 66 67 N 5 12735 11516 2434 Blue 10
10 AM Tue 70 73 N 5 14010 13354 4272 Blue 16
11 AM Tue 73 78 E 8 17019 14808 5726 Blue 21
12 Noon Tue 75 81 E 8 18715 16888 7806 White 24
1 PM Tue 76 82 E 8 18931 17393 8311 White 25
2 PM Tue 77 83 E 8 19147 17884 8802 White 26
3 PM Tue 77 82 E 8 18931 17393 8311 White 25
4 PM Tue 77 80 E 8 18025 16367 7285 Blue 23
5 PM Tue 76 77 S 9 16492 14185 5103 Blue 20
6 PM Tue 74 74 S 9 14219 13563 4481 Blue 17
7 PM Tue 71 71 S 9 13592 12935 3853 Blue 14
8 PM Tue 68 68 S 9 12961 11564 2482 Blue 11
9 PM Tue 64 64 S 9 11519 11368 2286 Blue 7
10 PM Tue 61 61 S 9 11371 10132 1050 Blue 4
11 PM Tue 59 59 SW 7 11246 9085 3 Blue 2
12 Midnight Wed 58 58 SW 7 10147 9085 3 Blue 1
1 AM Wed 57 57 SW 7 9085 9085 3 Blue 0
2 AM Wed 56 56 SW 7 9085 9085 3 Blue 0
3 AM Wed 54 54 SW 7 9085 9085 3 Blue 0
4 AM Wed 53 53 SW 7 9085 9085 3 Blue 0
5 AM Wed 52 52 SW 5 9085 9085 3 Blue 0
6 AM Wed 54 54 SW 5 9085 9085 3 Blue 0
7 AM Wed 57 57 SW 5 9085 9085 3 Blue 0
8 AM Wed 61 61 SW 5 11371 10132 1050 Blue 4
9 AM Wed 65 67 SW 5 12735 11516 2434 Blue 10
10 AM Wed 69 72 SW 5 13802 13145 4063 Blue 15
11 AM Wed 72 75 S 9 14964 13771 4689 Blue 18
12 Noon Wed 73 77 S 9 16492 14185 5103 Blue 20
1 PM Wed 74 78 S 9 17019 14808 5726 Blue 21
2 PM Wed 74 78 S 9 17019 14808 5726 Blue 21
3 PM Wed 74 77 S 9 16492 14185 5103 Blue 20
4 PM Wed 74 76 S 9 15781 13978 4896 Blue 19
5 PM Wed 73 74 SW 13 14219 13563 4481 Blue 17
6 PM Wed 71 71 SW 13 13592 12935 3853 Blue 14
7 PM Wed 69 69 SW 13 13172 11664 2582 Blue 12
8 PM Wed 66 66 SW 13 11690 11467 2385 Blue 9
9 PM Wed 63 63 SW 13 11471 11318 2236 Blue 6
10 PM Wed 61 61 SW 13 11371 10132 1050 Blue 4
11 PM Wed 58 58 SW 6 10147 9085 3 Blue 1
12 Midnight Thu 56 56 SW 6 9085 9085 3 Blue 0
1 AM Thu 54 54 SW 6 9085 9085 3 Blue 0
2 AM Thu 52 52 SW 6 9085 9085 3 Blue 0
3 AM Thu 51 51 SW 6 9085 9085 3 Blue 0
4 AM Thu 50 50 SW 6 9085 9085 3 Blue 0
5 AM Thu 51 51 SW 3 9085 9085 3 Blue 0
6 AM Thu 53 53 SW 3 9085 9085 3 Blue 0
7 AM Thu 56 56 SW 3 9085 9085 3 Blue 0
8 AM Thu 59 59 SW 3 11246 9085 3 Blue 2
9 AM Thu 63 64 SW 3 11519 11368 2286 Blue 7
10 AM Thu 67 70 SW 3 13382 12627 3545 Blue 13
11 AM Thu 70 74 SW 9 14219 13563 4481 Blue 17
12 Noon Thu 72 77 SW 9 16492 14185 5103 Blue 20
1 PM Thu 74 79 SW 9 17529 15616 6534 Blue 22
2 PM Thu 75 80 SW 9 18025 16367 7285 Blue 23
3 PM Thu 75 79 SW 9 17529 15616 6534 Blue 22
4 PM Thu 74 77 SW 9 16492 14185 5103 Blue 20
5 PM Thu 73 74 SW 12 14219 13563 4481 Blue 17
6 PM Thu 70 70 SW 12 13382 12627 3545 Blue 13
7 PM Thu 68 68 SW 12 12961 11564 2482 Blue 11
8 PM Thu 65 65 SW 12 11568 11418 2336 Blue 8
9 PM Thu 62 62 SW 12 11421 11132 2050 Blue 5
10 PM Thu 60 60 SW 12 11322 9085 3 Blue 3
11 PM Thu 57 57 W 7 9085 9085 3 Blue 0
12 Midnight Fri 55 55 W 7 9085 9085 3 Blue 0
1 AM Fri 53 53 W 7 9085 9085 3 Blue 0
2 AM Fri 51 51 W 7 9085 9085 3 Blue 0
3 AM Fri 50 50 W 7 9085 9085 3 Blue 0
4 AM Fri 49 49 W 7 9085 9085 3 Blue 0
5 AM Fri 49 49 W 6 9085 9085 3 Blue 0
6 AM Fri 51 51 W 6 9085 9085 3 Blue 0
7 AM Fri 54 54 W 6 9085 9085 3 Blue 0
8 AM Fri 58 58 W 6 10147 9085 3 Blue 1
9 AM Fri 62 64 W 6 11519 11368 2286 Blue 7
10 AM Fri 67 71 W 6 13592 12935 3853 Blue 14
11 AM Fri 70 75 SW 8 14964 13771 4689 Blue 18
12 Noon Fri 73 79 SW 8 17529 15616 6534 Blue 22
1 PM Fri 76 83 SW 8 19147 17884 8802 White 26
2 PM Fri 77 83 SW 8 19147 17884 8802 White 26
3 PM Fri 77 82 SW 8 18931 17393 8311 White 25
4 PM Fri 76 80 SW 8 18025 16367 7285 Blue 23
5 PM Fri 75 77 SW 14 16492 14185 5103 Blue 20
6 PM Fri 72 72 SW 14 13802 13145 4063 Blue 15
7 PM Fri 69 69 SW 14 13172 11664 2582 Blue 12
8 PM Fri 66 66 SW 14 11690 11467 2385 Blue 9
9 PM Fri 64 64 SW 14 11519 11368 2286 Blue 7
10 PM Fri 61 61 SW 14 11371 10132 1050 Blue 4
11 PM Fri 59 59 W 7 11246 9085 3 Blue 2
12 Midnight Sat 57 57 W 7 9085 9085 3 Blue 0
1 AM Sat 54 54 W 7 9085 9085 3 Blue 0
2 AM Sat 52 52 W 7 9085 9085 3 Blue 0
3 AM Sat 51 51 W 7 9085 9085 3 Blue 0
4 AM Sat 50 50 W 7 9085 9085 3 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