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

Station:

KVBG

Date/Time:

20 NOV 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)
4 AM Mon 37 37 SW 21 5886 9082 0 Blue 0
5 AM Mon 36 36 SW 21 5886 9082 0 Blue 0
6 AM Mon 36 36 SW 21 5886 9082 0 Blue 0
7 AM Mon 37 37 SW 23 5886 9082 0 Blue 0
8 AM Mon 40 40 SW 23 6766 9082 0 Blue 0
9 AM Mon 43 43 SW 23 7703 9082 0 Blue 0
10 AM Mon 46 46 W 14 8620 9082 0 Blue 0
11 AM Mon 47 47 W 14 8921 9082 0 Blue 0
12 Noon Mon 48 48 W 14 9221 9082 0 Blue 0
1 PM Mon 48 48 W 18 9221 9082 0 Blue 0
2 PM Mon 48 48 W 18 9221 9082 0 Blue 0
3 PM Mon 47 47 W 18 8921 9082 0 Blue 0
4 PM Mon 45 45 W 9 8316 9082 0 Blue 0
5 PM Mon 44 44 W 9 8011 9082 0 Blue 0
6 PM Mon 42 42 W 9 7393 9082 0 Blue 0
7 PM Mon 40 40 W 8 6766 9082 0 Blue 0
8 PM Mon 39 39 W 8 6448 9082 0 Blue 0
9 PM Mon 38 38 W 8 6129 9082 0 Blue 0
10 PM Mon 38 38 SW 6 6129 9082 0 Blue 0
11 PM Mon 38 38 SW 6 6129 9082 0 Blue 0
12 Midnight Tue 37 37 SW 6 5886 9082 0 Blue 0
1 AM Tue 37 37 SW 6 5886 9082 0 Blue 0
2 AM Tue 37 37 SW 6 5886 9082 0 Blue 0
3 AM Tue 37 37 SW 6 5886 9082 0 Blue 0
4 AM Tue 37 37 SW 8 5886 9082 0 Blue 0
5 AM Tue 36 36 SW 8 5886 9082 0 Blue 0
6 AM Tue 36 36 SW 8 5886 9082 0 Blue 0
7 AM Tue 38 38 SW 8 6129 9082 0 Blue 0
8 AM Tue 42 42 SW 8 7393 9082 0 Blue 0
9 AM Tue 47 47 SW 8 8921 9082 0 Blue 0
10 AM Tue 51 52 SW 5 10404 9515 433 Blue 1
11 AM Tue 54 55 SW 5 11694 10392 1310 Blue 4
12 Noon Tue 55 56 SW 5 12201 10687 1605 Blue 5
1 PM Tue 55 56 SW 5 12201 10687 1605 Blue 5
2 PM Tue 55 56 SW 5 12201 10687 1605 Blue 5
3 PM Tue 54 54 SW 5 11174 10099 1017 Blue 3
4 PM Tue 53 53 W 7 10702 9808 726 Blue 2
5 PM Tue 50 50 W 7 9814 9082 0 Blue 0
6 PM Tue 47 47 W 7 8921 9082 0 Blue 0
7 PM Tue 44 44 W 7 8011 9082 0 Blue 0
8 PM Tue 42 42 W 7 7393 9082 0 Blue 0
9 PM Tue 41 41 W 7 7080 9082 0 Blue 0
10 PM Tue 41 41 SW 6 7080 9082 0 Blue 0
11 PM Tue 40 40 SW 6 6766 9082 0 Blue 0
12 Midnight Wed 40 40 SW 6 6766 9082 0 Blue 0
1 AM Wed 39 39 SW 6 6448 9082 0 Blue 0
2 AM Wed 39 39 SW 6 6448 9082 0 Blue 0
3 AM Wed 38 38 SW 6 6129 9082 0 Blue 0
4 AM Wed 38 38 SW 5 6129 9082 0 Blue 0
5 AM Wed 36 36 SW 5 5886 9082 0 Blue 0
6 AM Wed 36 36 SW 5 5886 9082 0 Blue 0
7 AM Wed 38 38 SW 5 6129 9082 0 Blue 0
8 AM Wed 42 42 SW 5 7393 9082 0 Blue 0
9 AM Wed 49 50 SW 5 9814 9082 0 Blue 0
10 AM Wed 54 55 S 5 11694 10392 1310 Blue 4
11 AM Wed 57 59 S 5 14437 12152 3070 Blue 7
12 Noon Wed 58 60 S 5 14571 12727 3645 Blue 8
1 PM Wed 58 60 S 5 14571 12727 3645 Blue 8
2 PM Wed 58 59 S 5 14437 12152 3070 Blue 7
3 PM Wed 56 56 S 5 12201 10687 1605 Blue 5
4 PM Wed 54 54 SW 5 11174 10099 1017 Blue 3
5 PM Wed 51 51 SW 5 10108 9220 138 Blue 0
6 PM Wed 46 46 SW 5 8620 9082 0 Blue 0
7 PM Wed 42 42 SW 5 7393 9082 0 Blue 0
8 PM Wed 40 40 SW 5 6766 9082 0 Blue 0
9 PM Wed 38 38 SW 5 6129 9082 0 Blue 0
10 PM Wed 38 38 S 5 6129 9082 0 Blue 0
11 PM Wed 38 38 S 5 6129 9082 0 Blue 0
12 Midnight Thu 37 37 S 5 5886 9082 0 Blue 0
1 AM Thu 37 37 S 5 5886 9082 0 Blue 0
2 AM Thu 36 36 S 5 5886 9082 0 Blue 0
3 AM Thu 35 35 S 5 5886 9082 0 Blue 0
4 AM Thu 34 34 SW 7 5886 9082 0 Blue 0
5 AM Thu 34 34 SW 7 5886 9082 0 Blue 0
6 AM Thu 35 35 SW 7 5886 9082 0 Blue 0
7 AM Thu 38 38 SW 7 6129 9082 0 Blue 0
8 AM Thu 43 43 SW 7 7703 9082 0 Blue 0
9 AM Thu 48 48 SW 7 9221 9082 0 Blue 0
10 AM Thu 53 54 SW 8 11174 10099 1017 Blue 3
11 AM Thu 56 57 SW 8 12883 11140 2058 Blue 5
12 Noon Thu 58 59 SW 8 14437 12152 3070 Blue 7
1 PM Thu 58 59 SW 8 14437 12152 3070 Blue 7
2 PM Thu 58 59 SW 8 14437 12152 3070 Blue 7
3 PM Thu 56 56 SW 8 12201 10687 1605 Blue 5
4 PM Thu 54 54 SW 8 11174 10099 1017 Blue 3
5 PM Thu 51 51 SW 8 10108 9220 138 Blue 0
6 PM Thu 47 47 SW 8 8921 9082 0 Blue 0
7 PM Thu 44 44 SW 8 8011 9082 0 Blue 0
8 PM Thu 41 41 SW 8 7080 9082 0 Blue 0
9 PM Thu 40 40 SW 8 6766 9082 0 Blue 0
10 PM Thu 39 39 SW 8 6448 9082 0 Blue 0
11 PM Thu 39 39 SW 8 6448 9082 0 Blue 0
12 Midnight Fri 39 39 SW 8 6448 9082 0 Blue 0
1 AM Fri 38 38 SW 8 6129 9082 0 Blue 0
2 AM Fri 36 36 SW 8 5886 9082 0 Blue 0
3 AM Fri 35 35 SW 8 5886 9082 0 Blue 0
4 AM Fri 33 33 SW 10 5886 9082 0 Blue 0
5 AM Fri 33 33 SW 10 5886 9082 0 Blue 0
6 AM Fri 34 34 SW 10 5886 9082 0 Blue 0
7 AM Fri 37 37 SW 10 5886 9082 0 Blue 0
8 AM Fri 42 42 SW 10 7393 9082 0 Blue 0
9 AM Fri 48 48 SW 10 9221 9082 0 Blue 0
10 AM Fri 53 54 SW 8 11174 10099 1017 Blue 3
11 AM Fri 56 57 SW 8 12883 11140 2058 Blue 5
12 Noon Fri 58 59 SW 8 14437 12152 3070 Blue 7
1 PM Fri 58 59 SW 8 14437 12152 3070 Blue 7
2 PM Fri 57 58 SW 8 14090 11653 2571 Blue 6
3 PM Fri 55 55 SW 8 11694 10392 1310 Blue 4
4 PM Fri 53 53 SW 7 10702 9808 726 Blue 2
5 PM Fri 49 49 SW 7 9519 9082 0 Blue 0
6 PM Fri 46 46 SW 7 8620 9082 0 Blue 0
7 PM Fri 43 43 SW 7 7703 9082 0 Blue 0
8 PM Fri 39 39 SW 7 6448 9082 0 Blue 0
9 PM Fri 36 36 SW 7 5886 9082 0 Blue 0
10 PM Fri 35 35 SW 7 5886 9082 0 Blue 0
11 PM Fri 35 35 SW 7 5886 9082 0 Blue 0
12 Midnight Sat 36 36 SW 7 5886 9082 0 Blue 0
1 AM Sat 36 36 SW 7 5886 9082 0 Blue 0
2 AM Sat 35 35 SW 7 5886 9082 0 Blue 0
3 AM Sat 33 33 SW 7 5886 9082 0 Blue 0
4 AM Sat 32 32 SW 9 5886 9082 0 Blue 0
5 AM Sat 31 31 SW 9 5886 9082 0 Blue 0
6 AM Sat 32 32 SW 9 5886 9082 0 Blue 0
7 AM Sat 35 35 SW 9 5886 9082 0 Blue 0
8 AM Sat 39 39 SW 9 6448 9082 0 Blue 0
9 AM Sat 45 45 SW 9 8316 9082 0 Blue 0
10 AM Sat 50 51 S 15 10108 9220 138 Blue 0
11 AM Sat 53 54 S 15 11174 10099 1017 Blue 3
12 Noon Sat 54 55 S 15 11694 10392 1310 Blue 4
1 PM Sat 54 55 S 15 11694 10392 1310 Blue 4
2 PM Sat 53 54 S 15 11174 10099 1017 Blue 3
3 PM Sat 51 51 S 15 10108 9220 138 Blue 0
4 PM Sat 49 49 S 16 9519 9082 0 Blue 0
5 PM Sat 46 46 S 16 8620 9082 0 Blue 0
6 PM Sat 43 43 S 16 7703 9082 0 Blue 0
7 PM Sat 40 40 S 16 6766 9082 0 Blue 0
8 PM Sat 37 37 S 16 5886 9082 0 Blue 0
9 PM Sat 35 35 S 16 5886 9082 0 Blue 0
10 PM Sat 35 35 SW 16 5886 9082 0 Blue 0
11 PM Sat 34 34 SW 16 5886 9082 0 Blue 0
12 Midnight Sun 35 35 SW 16 5886 9082 0 Blue 0
1 AM Sun 35 35 SW 16 5886 9082 0 Blue 0
2 AM Sun 33 33 SW 16 5886 9082 0 Blue 0
3 AM Sun 32 32 SW 16 5886 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