Detailed Predictions for: McGee Creek
Launch Altitude (f): 9082
LZ Altitude (f): 7122
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 47 47 NW 2 5902 9082 0 Blue 0
6 AM Wed 53 53 NW 2 5902 9082 0 Blue 0
7 AM Wed 56 56 NW 2 5902 9082 0 Blue 0
8 AM Wed 59 59 N 2 7026 9082 0 Blue 0
9 AM Wed 63 65 N 2 11258 9257 175 Blue 1
10 AM Wed 66 69 N 2 13639 11843 2761 Blue 5
11 AM Wed 69 74 E 5 16019 14543 5461 Blue 10
12 Noon Wed 71 77 E 5 17326 15921 6839 Blue 13
1 PM Wed 73 80 E 5 18599 17214 8132 Blue 16
2 PM Wed 74 80 S 5 18599 17214 8132 Blue 16
3 PM Wed 75 80 S 5 18599 17214 8132 Blue 16
4 PM Wed 74 78 S 5 17745 16361 7279 Blue 14
5 PM Wed 73 75 SW 10 16464 15013 5931 Blue 11
6 PM Wed 71 71 SW 10 14626 13026 3944 Blue 7
7 PM Wed 68 68 SW 10 13097 11216 2134 Blue 4
8 PM Wed 65 65 W 8 11258 9257 175 Blue 1
9 PM Wed 63 63 W 8 9931 9082 0 Blue 0
10 PM Wed 60 60 W 8 7814 9082 0 Blue 0
11 PM Wed 59 59 SW 6 7026 9082 0 Blue 0
12 Midnight Thu 57 57 SW 6 5902 9082 0 Blue 0
1 AM Thu 55 55 SW 6 5902 9082 0 Blue 0
2 AM Thu 54 54 W 2 5902 9082 0 Blue 0
3 AM Thu 52 52 W 2 5902 9082 0 Blue 0
4 AM Thu 50 50 W 2 5902 9082 0 Blue 0
5 AM Thu 50 50 N 3 5902 9082 0 Blue 0
6 AM Thu 52 52 N 3 5902 9082 0 Blue 0
7 AM Thu 56 56 N 3 5902 9082 0 Blue 0
8 AM Thu 60 60 NW 5 7814 9082 0 Blue 0
9 AM Thu 64 65 NW 5 11258 9257 175 Blue 1
10 AM Thu 67 70 NW 5 14139 12446 3364 Blue 6
11 AM Thu 70 75 SE 5 16464 15013 5931 Blue 11
12 Noon Thu 73 79 SE 5 18169 16792 7710 Blue 15
1 PM Thu 75 82 SE 5 19460 18043 8961 Blue 18
2 PM Thu 77 83 SW 6 20092 18468 9386 Blue 19
3 PM Thu 77 82 SW 6 19460 18043 8961 Blue 18
4 PM Thu 77 81 SW 6 19020 17629 8547 Blue 17
5 PM Thu 76 78 W 9 17745 16361 7279 Blue 14
6 PM Thu 73 74 W 9 16019 14543 5461 Blue 10
7 PM Thu 70 70 W 9 14139 12446 3364 Blue 6
8 PM Thu 67 67 W 9 12508 10560 1478 Blue 3
9 PM Thu 63 63 W 9 9931 9082 0 Blue 0
10 PM Thu 60 60 W 9 7814 9082 0 Blue 0
11 PM Thu 57 57 N 3 5902 9082 0 Blue 0
12 Midnight Fri 55 55 N 3 5902 9082 0 Blue 0
1 AM Fri 54 54 N 3 5902 9082 0 Blue 0
2 AM Fri 52 52 N 3 5902 9082 0 Blue 0
3 AM Fri 50 50 N 3 5902 9082 0 Blue 0
4 AM Fri 48 48 N 3 5902 9082 0 Blue 0
5 AM Fri 48 48 SE 3 5902 9082 0 Blue 0
6 AM Fri 50 50 SE 3 5902 9082 0 Blue 0
7 AM Fri 54 54 SE 3 5902 9082 0 Blue 0
8 AM Fri 58 58 SE 3 6182 9082 0 Blue 0
9 AM Fri 63 65 SE 3 11258 9257 175 Blue 1
10 AM Fri 67 70 SE 3 14139 12446 3364 Blue 6
11 AM Fri 70 75 SE 8 16464 15013 5931 Blue 11
12 Noon Fri 73 79 SE 8 18169 16792 7710 Blue 15
1 PM Fri 75 82 SE 8 19460 18043 8961 Blue 18
2 PM Fri 76 82 SE 8 19460 18043 8961 Blue 18
3 PM Fri 77 82 SE 8 19460 18043 8961 Blue 18
4 PM Fri 76 80 SE 8 18599 17214 8132 Blue 16
5 PM Fri 75 77 SW 9 17326 15921 6839 Blue 13
6 PM Fri 72 72 SW 9 15102 13568 4486 Blue 8
7 PM Fri 69 69 SW 9 13639 11843 2761 Blue 5
8 PM Fri 66 66 SW 9 11896 9915 833 Blue 2
9 PM Fri 63 63 SW 9 9931 9082 0 Blue 0
10 PM Fri 60 60 SW 9 7814 9082 0 Blue 0
11 PM Fri 58 58 SW 5 6182 9082 0 Blue 0
12 Midnight Sat 57 57 SW 5 5902 9082 0 Blue 0
1 AM Sat 56 56 SW 5 5902 9082 0 Blue 0
2 AM Sat 54 54 SW 5 5902 9082 0 Blue 0
3 AM Sat 52 52 SW 5 5902 9082 0 Blue 0
4 AM Sat 51 51 SW 5 5902 9082 0 Blue 0
5 AM Sat 51 51 S 3 5902 9082 0 Blue 0
6 AM Sat 53 53 S 3 5902 9082 0 Blue 0
7 AM Sat 56 56 S 3 5902 9082 0 Blue 0
8 AM Sat 59 59 S 3 7026 9082 0 Blue 0
9 AM Sat 62 64 S 3 10590 9082 0 Blue 0
10 AM Sat 65 69 S 3 13639 11843 2761 Blue 5
11 AM Sat 68 74 E 6 16019 14543 5461 Blue 10
12 Noon Sat 70 77 E 6 17326 15921 6839 Blue 13
1 PM Sat 73 80 E 6 18599 17214 8132 Blue 16
2 PM Sat 74 81 E 6 19020 17629 8547 Blue 17
3 PM Sat 74 80 E 6 18599 17214 8132 Blue 16
4 PM Sat 73 77 E 6 17326 15921 6839 Blue 13
5 PM Sat 72 74 S 10 16019 14543 5461 Blue 10
6 PM Sat 70 70 S 10 14139 12446 3364 Blue 6
7 PM Sat 68 68 S 10 13097 11216 2134 Blue 4
8 PM Sat 65 65 S 10 11258 9257 175 Blue 1
9 PM Sat 62 62 S 10 9260 9082 0 Blue 0
10 PM Sat 59 59 S 10 7026 9082 0 Blue 0
11 PM Sat 56 56 SW 3 5902 9082 0 Blue 0
12 Midnight Sun 54 54 SW 3 5902 9082 0 Blue 0
1 AM Sun 53 53 SW 3 5902 9082 0 Blue 0
2 AM Sun 52 52 SW 3 5902 9082 0 Blue 0
3 AM Sun 50 50 SW 3 5902 9082 0 Blue 0
4 AM Sun 48 48 SW 3 5902 9082 0 Blue 0
5 AM Sun 48 48 SW 3 5902 9082 0 Blue 0
6 AM Sun 50 50 SW 3 5902 9082 0 Blue 0
7 AM Sun 54 54 SW 3 5902 9082 0 Blue 0
8 AM Sun 58 58 SW 3 6182 9082 0 Blue 0
9 AM Sun 62 64 SW 3 10590 9082 0 Blue 0
10 AM Sun 66 70 SW 3 14139 12446 3364 Blue 6
11 AM Sun 69 75 E 6 16464 15013 5931 Blue 11
12 Noon Sun 72 79 E 6 18169 16792 7710 Blue 15
1 PM Sun 75 82 E 6 19460 18043 8961 Blue 18
2 PM Sun 76 83 E 6 20092 18468 9386 Blue 19
3 PM Sun 75 81 E 6 19020 17629 8547 Blue 17
4 PM Sun 73 77 E 6 17326 15921 6839 Blue 13
5 PM Sun 71 73 SW 10 15566 14062 4980 Blue 9
6 PM Sun 70 70 SW 10 14139 12446 3364 Blue 6
7 PM Sun 69 69 SW 10 13639 11843 2761 Blue 5
8 PM Sun 68 68 SW 10 13097 11216 2134 Blue 4
9 PM Sun 65 65 SW 10 11258 9257 175 Blue 1
10 PM Sun 61 61 SW 10 8556 9082 0 Blue 0
11 PM Sun 57 57 SW 2 5902 9082 0 Blue 0
12 Midnight Mon 55 55 SW 2 5902 9082 0 Blue 0
1 AM Mon 54 54 SW 2 5902 9082 0 Blue 0
2 AM Mon 52 52 SW 2 5902 9082 0 Blue 0
3 AM Mon 50 50 SW 2 5902 9082 0 Blue 0
4 AM Mon 48 48 SW 2 5902 9082 0 Blue 0
5 AM Mon 48 48 W 2 5902 9082 0 Blue 0
6 AM Mon 51 51 W 2 5902 9082 0 Blue 0
7 AM Mon 55 55 W 2 5902 9082 0 Blue 0
8 AM Mon 59 59 W 2 7026 9082 0 Blue 0
9 AM Mon 63 65 W 2 11258 9257 175 Blue 1
10 AM Mon 65 69 W 2 13639 11843 2761 Blue 5
11 AM Mon 68 73 E 5 15566 14062 4980 Blue 9
12 Noon Mon 71 77 E 5 17326 15921 6839 Blue 13
1 PM Mon 74 81 E 5 19020 17629 8547 Blue 17
2 PM Mon 76 82 E 5 19460 18043 8961 Blue 18
3 PM Mon 75 80 E 5 18599 17214 8132 Blue 16
4 PM Mon 73 77 E 5 17326 15921 6839 Blue 13
5 PM Mon 71 73 SW 7 15566 14062 4980 Blue 9
6 PM Mon 70 70 SW 7 14139 12446 3364 Blue 6
7 PM Mon 69 69 SW 7 13639 11843 2761 Blue 5
8 PM Mon 68 68 SW 7 13097 11216 2134 Blue 4
9 PM Mon 66 66 SW 7 11896 9915 833 Blue 2
10 PM Mon 63 63 SW 7 9931 9082 0 Blue 0
11 PM Mon 60 60 NW 1 7814 9082 0 Blue 0
12 Midnight Tue 57 57 NW 1 5902 9082 0 Blue 0
1 AM Tue 55 55 NW 1 5902 9082 0 Blue 0
2 AM Tue 54 54 NW 1 5902 9082 0 Blue 0
3 AM Tue 52 52 NW 1 5902 9082 0 Blue 0
4 AM Tue 51 51 NW 1 5902 9082 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