Detailed Predictions for: Mt Crested Butte
Launch Altitude (f): 11500
LZ Altitude (f): 8700
Sounding

Station:

KGJT

Date/Time:

21 JUL 2018

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)
6 AM Sat 50 50 E 3 8366 11500 0 Blue 0
7 AM Sat 53 53 E 2 8366 11500 0 Blue 0
8 AM Sat 58 60 S 2 8366 11500 0 Blue 0
9 AM Sat 62 65 SW 3 9191 11500 0 Blue 0
10 AM Sat 67 71 W 5 16293 11500 0 White 4
11 AM Sat 70 75 W 6 17150 17150 5650 White 8
12 Noon Sat 72 76 W 7 17364 17364 5864 White 9
1 PM Sat 73 77 W 8 17577 17577 6077 White 10
2 PM Sat 73 76 W 9 17364 17364 5864 White 9
3 PM Sat 73 75 W 8 17150 17150 5650 White 8
4 PM Sat 73 74 W 9 16937 16477 4977 White 7
5 PM Sat 72 72 W 8 16508 14338 2838 White 5
6 PM Sat 70 70 W 7 16076 11500 0 White 3
7 PM Sat 66 66 W 7 9779 11500 0 Blue 0
8 PM Sat 62 62 SW 6 8366 11500 0 Blue 0
9 PM Sat 58 58 W 5 8366 11500 0 Blue 0
10 PM Sat 56 56 E 5 8366 11500 0 Blue 0
11 PM Sat 55 55 NE 5 8366 11500 0 Blue 0
12 Midnight Sun 55 55 NE 3 8366 11500 0 Blue 0
1 AM Sun 54 54 E 3 8366 11500 0 Blue 0
2 AM Sun 54 54 NE 3 8366 11500 0 Blue 0
3 AM Sun 53 53 NE 3 8366 11500 0 Blue 0
4 AM Sun 51 51 NE 3 8366 11500 0 Blue 0
5 AM Sun 50 50 N 3 8366 11500 0 Blue 0
6 AM Sun 50 50 N 3 8366 11500 0 Blue 0
7 AM Sun 53 53 N 3 8366 11500 0 Blue 0
8 AM Sun 58 59 W 3 8366 11500 0 Blue 0
9 AM Sun 64 66 W 3 9779 11500 0 Blue 0
10 AM Sun 68 70 W 5 16076 11500 0 White 3
11 AM Sun 72 74 W 5 16937 16477 4977 White 7
12 Noon Sun 74 76 W 6 17364 17364 5864 White 9
1 PM Sun 75 77 W 7 17577 17577 6077 White 10
2 PM Sun 75 77 W 7 17577 17577 6077 White 10
3 PM Sun 75 76 W 8 17364 17364 5864 White 9
4 PM Sun 74 75 NW 8 17150 17150 5650 White 8
5 PM Sun 73 73 NW 8 16723 15866 4366 White 6
6 PM Sun 71 71 NW 8 16293 11500 0 White 4
7 PM Sun 67 67 N 7 10348 11500 0 Blue 0
8 PM Sun 64 64 N 5 8583 11500 0 Blue 0
9 PM Sun 60 60 NE 3 8366 11500 0 Blue 0
10 PM Sun 58 58 NE 3 8366 11500 0 Blue 0
11 PM Sun 56 56 NE 3 8366 11500 0 Blue 0
12 Midnight Mon 55 55 E 3 8366 11500 0 Blue 0
1 AM Mon 54 54 E 3 8366 11500 0 Blue 0
2 AM Mon 53 53 E 3 8366 11500 0 Blue 0
3 AM Mon 51 51 E 3 8366 11500 0 Blue 0
4 AM Mon 49 49 E 3 8366 11500 0 Blue 0
5 AM Mon 48 48 E 5 8366 11500 0 Blue 0
6 AM Mon 48 48 E 5 8366 11500 0 Blue 0
7 AM Mon 52 52 E 5 8366 11500 0 Blue 0
8 AM Mon 57 57 SE 3 8366 11500 0 Blue 0
9 AM Mon 62 62 SE 3 8366 11500 0 Blue 0
10 AM Mon 67 68 S 3 10955 11500 0 Blue 1
11 AM Mon 70 71 SW 5 16293 11500 0 White 4
12 Noon Mon 72 73 W 5 16723 15866 4366 White 6
1 PM Mon 72 73 W 5 16723 15866 4366 White 6
2 PM Mon 73 73 W 6 16723 15866 4366 White 6
3 PM Mon 72 72 W 6 16508 14338 2838 White 5
4 PM Mon 71 71 NW 6 16293 11500 0 White 4
5 PM Mon 70 70 N 6 16076 11500 0 White 3
6 PM Mon 68 68 N 6 10955 11500 0 Blue 1
7 PM Mon 65 65 N 6 9191 11500 0 Blue 0
8 PM Mon 62 62 E 5 8366 11500 0 Blue 0
9 PM Mon 59 59 SE 5 8366 11500 0 Blue 0
10 PM Mon 57 57 SE 5 8366 11500 0 Blue 0
11 PM Mon 55 55 SE 5 8366 11500 0 Blue 0
12 Midnight Tue 53 53 E 5 8366 11500 0 Blue 0
1 AM Tue 52 52 SE 5 8366 11500 0 Blue 0
2 AM Tue 51 51 SE 5 8366 11500 0 Blue 0
3 AM Tue 50 50 SE 5 8366 11500 0 Blue 0
4 AM Tue 48 48 SE 5 8366 11500 0 Blue 0
5 AM Tue 47 47 E 3 8366 11500 0 Blue 0
6 AM Tue 48 48 E 3 8366 11500 0 Blue 0
7 AM Tue 50 50 E 3 8366 11500 0 Blue 0
8 AM Tue 53 54 NE 3 8366 11500 0 Blue 0
9 AM Tue 57 58 N 3 8366 11500 0 Blue 0
10 AM Tue 62 64 N 3 8583 11500 0 Blue 0
11 AM Tue 66 68 NW 3 10955 11500 0 Blue 1
12 Noon Tue 69 72 NW 3 16508 14338 2838 White 5
1 PM Tue 71 73 NW 3 16723 15866 4366 White 6
2 PM Tue 72 74 NW 5 16937 16477 4977 White 7
3 PM Tue 72 73 NW 5 16723 15866 4366 White 6
4 PM Tue 72 73 NW 6 16723 15866 4366 White 6
5 PM Tue 70 70 NW 6 16076 11500 0 White 3
6 PM Tue 68 68 NW 6 10955 11500 0 Blue 1
7 PM Tue 66 66 NW 6 9779 11500 0 Blue 0
8 PM Tue 64 64 NW 6 8583 11500 0 Blue 0
9 PM Tue 62 62 NW 6 8366 11500 0 Blue 0
10 PM Tue 59 59 NW 6 8366 11500 0 Blue 0
11 PM Tue 56 56 NW 6 8366 11500 0 Blue 0
12 Midnight Wed 54 54 SE 3 8366 11500 0 Blue 0
1 AM Wed 52 52 SE 3 8366 11500 0 Blue 0
2 AM Wed 49 49 SE 3 8366 11500 0 Blue 0
3 AM Wed 48 48 SE 3 8366 11500 0 Blue 0
4 AM Wed 47 47 SE 3 8366 11500 0 Blue 0
5 AM Wed 48 48 SE 3 8366 11500 0 Blue 0
6 AM Wed 49 49 NE 3 8366 11500 0 Blue 0
7 AM Wed 52 52 NE 3 8366 11500 0 Blue 0
8 AM Wed 56 57 NE 3 8366 11500 0 Blue 0
9 AM Wed 60 62 NE 3 8366 11500 0 Blue 0
10 AM Wed 65 68 NE 3 10955 11500 0 Blue 1
11 AM Wed 69 73 NE 3 16723 15866 4366 White 6
12 Noon Wed 72 75 NW 5 17150 17150 5650 White 8
1 PM Wed 74 77 NW 5 17577 17577 6077 White 10
2 PM Wed 74 76 NW 5 17364 17364 5864 White 9
3 PM Wed 74 76 NW 5 17364 17364 5864 White 9
4 PM Wed 73 74 NW 5 16937 16477 4977 White 7
5 PM Wed 71 71 NW 5 16293 11500 0 White 4
6 PM Wed 69 69 NW 7 14765 11500 0 Blue 2
7 PM Wed 66 66 NW 7 9779 11500 0 Blue 0
8 PM Wed 64 64 NW 7 8583 11500 0 Blue 0
9 PM Wed 61 61 NW 7 8366 11500 0 Blue 0
10 PM Wed 59 59 NW 7 8366 11500 0 Blue 0
11 PM Wed 56 56 NW 7 8366 11500 0 Blue 0
12 Midnight Thu 54 54 SE 2 8366 11500 0 Blue 0
1 AM Thu 51 51 SE 2 8366 11500 0 Blue 0
2 AM Thu 49 49 SE 2 8366 11500 0 Blue 0
3 AM Thu 48 48 SE 2 8366 11500 0 Blue 0
4 AM Thu 47 47 SE 2 8366 11500 0 Blue 0
5 AM Thu 48 48 SE 2 8366 11500 0 Blue 0
6 AM Thu 49 49 NE 3 8366 11500 0 Blue 0
7 AM Thu 52 52 NE 3 8366 11500 0 Blue 0
8 AM Thu 55 56 NE 3 8366 11500 0 Blue 0
9 AM Thu 60 62 NE 3 8366 11500 0 Blue 0
10 AM Thu 64 67 NE 3 10348 11500 0 Blue 0
11 AM Thu 68 72 NE 3 16508 14338 2838 White 5
12 Noon Thu 71 73 NW 6 16723 15866 4366 White 6
1 PM Thu 73 75 NW 6 17150 17150 5650 White 8
2 PM Thu 74 76 NW 6 17364 17364 5864 White 9
3 PM Thu 74 75 NW 6 17150 17150 5650 White 8
4 PM Thu 73 74 NW 6 16937 16477 4977 White 7
5 PM Thu 71 71 NW 6 16293 11500 0 White 4
6 PM Thu 69 69 W 8 14765 11500 0 Blue 2
7 PM Thu 67 67 W 8 10348 11500 0 Blue 0
8 PM Thu 64 64 W 8 8583 11500 0 Blue 0
9 PM Thu 62 62 W 8 8366 11500 0 Blue 0
10 PM Thu 59 59 W 8 8366 11500 0 Blue 0
11 PM Thu 56 56 W 8 8366 11500 0 Blue 0
12 Midnight Fri 54 54 NE 3 8366 11500 0 Blue 0
1 AM Fri 51 51 NE 3 8366 11500 0 Blue 0
2 AM Fri 49 49 NE 3 8366 11500 0 Blue 0
3 AM Fri 47 47 NE 3 8366 11500 0 Blue 0
4 AM Fri 46 46 NE 3 8366 11500 0 Blue 0
5 AM Fri 47 47 NE 3 8366 11500 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