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

Station:

KGJT

Date/Time:

25 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)
6 AM Mon 24 24 N 2 7146 11500 0 Blue 0
7 AM Mon 27 27 N 3 7146 11500 0 Blue 0
8 AM Mon 31 32 W 3 7146 11500 0 Blue 0
9 AM Mon 34 36 SW 5 7245 11500 0 Blue 0
10 AM Mon 38 41 S 5 15294 13424 1924 White 3
11 AM Mon 40 44 S 5 15932 15932 4432 White 6
12 Noon Mon 43 47 SW 6 16563 16563 5063 White 9
1 PM Mon 45 49 SW 7 16979 16979 5479 White 11
2 PM Mon 46 49 SW 8 16979 16979 5479 White 11
3 PM Mon 47 49 W 9 16979 16979 5479 White 11
4 PM Mon 47 48 W 9 16772 16772 5272 White 10
5 PM Mon 46 46 W 8 16353 16353 4853 White 8
6 PM Mon 43 43 W 8 15721 15721 4221 White 5
7 PM Mon 39 39 NW 7 14863 11500 0 White 1
8 PM Mon 35 35 NW 7 7146 11500 0 Blue 0
9 PM Mon 31 31 N 6 7146 11500 0 Blue 0
10 PM Mon 29 29 N 5 7146 11500 0 Blue 0
11 PM Mon 28 28 N 5 7146 11500 0 Blue 0
12 Midnight Tue 28 28 E 3 7146 11500 0 Blue 0
1 AM Tue 28 28 E 3 7146 11500 0 Blue 0
2 AM Tue 28 28 E 3 7146 11500 0 Blue 0
3 AM Tue 28 28 E 3 7146 11500 0 Blue 0
4 AM Tue 28 28 E 5 7146 11500 0 Blue 0
5 AM Tue 28 28 E 5 7146 11500 0 Blue 0
6 AM Tue 29 29 E 5 7146 11500 0 Blue 0
7 AM Tue 28 28 E 3 7146 11500 0 Blue 0
8 AM Tue 31 32 SE 3 7146 11500 0 Blue 0
9 AM Tue 34 36 SE 3 7245 11500 0 Blue 0
10 AM Tue 38 41 SE 5 15294 13424 1924 White 3
11 AM Tue 43 47 S 5 16563 16563 5063 White 9
12 Noon Tue 47 51 S 6 17392 17392 5892 White 13
1 PM Tue 50 54 SW 7 18008 18008 6508 White 16
2 PM Tue 52 55 SW 7 18212 18212 6712 White 17
3 PM Tue 53 55 SW 7 18212 18212 6712 White 17
4 PM Tue 52 52 W 7 17598 17598 6098 White 14
5 PM Tue 51 51 W 7 17392 17392 5892 White 13
6 PM Tue 48 48 W 6 16772 16772 5272 White 10
7 PM Tue 45 45 SW 5 16144 16144 4644 White 7
8 PM Tue 40 40 S 5 15080 11500 0 White 2
9 PM Tue 37 37 SE 3 8896 11500 0 Blue 0
10 PM Tue 34 34 SE 3 7146 11500 0 Blue 0
11 PM Tue 32 32 SE 3 7146 11500 0 Blue 0
12 Midnight Wed 32 32 SE 3 7146 11500 0 Blue 0
1 AM Wed 32 32 SE 3 7146 11500 0 Blue 0
2 AM Wed 32 32 SE 3 7146 11500 0 Blue 0
3 AM Wed 32 32 SE 3 7146 11500 0 Blue 0
4 AM Wed 33 33 SE 3 7146 11500 0 Blue 0
5 AM Wed 33 33 SE 3 7146 11500 0 Blue 0
6 AM Wed 33 33 SE 3 7146 11500 0 Blue 0
7 AM Wed 34 34 SE 3 7146 11500 0 Blue 0
8 AM Wed 34 34 SE 3 7146 11500 0 Blue 0
9 AM Wed 37 37 SE 3 8896 11500 0 Blue 0
10 AM Wed 40 40 SE 5 15080 11500 0 White 2
11 AM Wed 44 45 S 5 16144 16144 4644 White 7
12 Noon Wed 48 49 S 6 16979 16979 5479 White 11
1 PM Wed 51 52 S 6 17598 17598 6098 White 14
2 PM Wed 52 52 S 6 17598 17598 6098 White 14
3 PM Wed 52 52 S 6 17598 17598 6098 White 14
4 PM Wed 50 50 SE 6 17186 17186 5686 White 12
5 PM Wed 48 48 SE 5 16772 16772 5272 White 10
6 PM Wed 45 45 E 5 16144 16144 4644 White 7
7 PM Wed 43 43 E 5 15721 15721 4221 White 5
8 PM Wed 41 41 SE 5 15294 13424 1924 White 3
9 PM Wed 39 39 SE 5 14863 11500 0 White 1
10 PM Wed 38 38 SE 5 13935 11500 0 Blue 0
11 PM Wed 37 37 SE 5 8896 11500 0 Blue 0
12 Midnight Thu 36 36 SE 5 7245 11500 0 Blue 0
1 AM Thu 36 36 SE 5 7245 11500 0 Blue 0
2 AM Thu 36 36 SE 3 7245 11500 0 Blue 0
3 AM Thu 36 36 SE 3 7245 11500 0 Blue 0
4 AM Thu 35 35 SE 3 7146 11500 0 Blue 0
5 AM Thu 35 35 SE 5 7146 11500 0 Blue 0
6 AM Thu 35 35 E 5 7146 11500 0 Blue 0
7 AM Thu 37 37 SE 5 8896 11500 0 Blue 0
8 AM Thu 39 39 SE 6 14863 11500 0 White 1
9 AM Thu 42 42 SE 6 15508 15508 4008 White 4
10 AM Thu 45 45 S 6 16144 16144 4644 White 7
11 AM Thu 48 48 S 6 16772 16772 5272 White 10
12 Noon Thu 50 50 S 6 17186 17186 5686 White 12
1 PM Thu 51 51 S 6 17392 17392 5892 White 13
2 PM Thu 52 52 S 6 17598 17598 6098 White 14
3 PM Thu 51 51 S 7 17392 17392 5892 White 13
4 PM Thu 50 50 S 7 17186 17186 5686 White 12
5 PM Thu 49 49 S 7 16979 16979 5479 White 11
6 PM Thu 47 47 S 6 16563 16563 5063 White 9
7 PM Thu 45 45 S 6 16144 16144 4644 White 7
8 PM Thu 43 43 S 6 15721 15721 4221 White 5
9 PM Thu 41 41 S 6 15294 13424 1924 White 3
10 PM Thu 40 40 S 6 15080 11500 0 White 2
11 PM Thu 38 38 S 6 13935 11500 0 Blue 0
12 Midnight Fri 36 36 SE 3 7245 11500 0 Blue 0
1 AM Fri 35 35 SE 3 7146 11500 0 Blue 0
2 AM Fri 34 34 SE 3 7146 11500 0 Blue 0
3 AM Fri 34 34 SE 3 7146 11500 0 Blue 0
4 AM Fri 34 34 SE 3 7146 11500 0 Blue 0
5 AM Fri 35 35 SE 3 7146 11500 0 Blue 0
6 AM Fri 36 36 SE 3 7245 11500 0 Blue 0
7 AM Fri 38 38 SE 3 13935 11500 0 Blue 0
8 AM Fri 41 41 SE 3 15294 13424 1924 White 3
9 AM Fri 44 44 SE 3 15932 15932 4432 White 6
10 AM Fri 47 48 SE 3 16772 16772 5272 White 10
11 AM Fri 50 51 SE 3 17392 17392 5892 White 13
12 Noon Fri 52 53 S 6 17803 17803 6303 White 15
1 PM Fri 53 54 S 6 18008 18008 6508 White 16
2 PM Fri 54 55 S 6 18212 18212 6712 White 17
3 PM Fri 54 54 S 6 18008 18008 6508 White 16
4 PM Fri 54 54 S 6 18008 18008 6508 White 16
5 PM Fri 52 52 S 6 17598 17598 6098 White 14
6 PM Fri 51 51 SW 6 17392 17392 5892 White 13
7 PM Fri 49 49 SW 6 16979 16979 5479 White 11
8 PM Fri 47 47 SW 6 16563 16563 5063 White 9
9 PM Fri 45 45 SW 6 16144 16144 4644 White 7
10 PM Fri 42 42 SW 6 15508 15508 4008 White 4
11 PM Fri 40 40 SW 6 15080 11500 0 White 2
12 Midnight Sat 38 38 S 3 13935 11500 0 Blue 0
1 AM Sat 36 36 S 3 7245 11500 0 Blue 0
2 AM Sat 35 35 S 3 7146 11500 0 Blue 0
3 AM Sat 35 35 S 3 7146 11500 0 Blue 0
4 AM Sat 35 35 S 3 7146 11500 0 Blue 0
5 AM Sat 35 35 S 3 7146 11500 0 Blue 0
6 AM Sat 37 37 S 3 8896 11500 0 Blue 0
7 AM Sat 39 39 S 3 14863 11500 0 White 1
8 AM Sat 41 41 S 3 15294 13424 1924 White 3
9 AM Sat 44 45 S 3 16144 16144 4644 White 7
10 AM Sat 47 48 S 3 16772 16772 5272 White 10
11 AM Sat 50 52 S 3 17598 17598 6098 White 14
12 Noon Sat 52 54 W 7 18008 18008 6508 White 16
1 PM Sat 54 56 W 7 18445 18445 6945 White 18
2 PM Sat 55 57 W 7 18663 18663 7163 White 19
3 PM Sat 55 56 W 7 18445 18445 6945 White 18
4 PM Sat 55 55 W 7 18212 18212 6712 White 17
5 PM Sat 54 54 W 7 18008 18008 6508 White 16
6 PM Sat 52 52 NW 6 17598 17598 6098 White 14
7 PM Sat 50 50 NW 6 17186 17186 5686 White 12
8 PM Sat 48 48 NW 6 16772 16772 5272 White 10
9 PM Sat 45 45 NW 6 16144 16144 4644 White 7
10 PM Sat 42 42 NW 6 15508 15508 4008 White 4
11 PM Sat 39 39 NW 6 14863 11500 0 White 1
12 Midnight Sun 37 37 N 2 8896 11500 0 Blue 0
1 AM Sun 35 35 N 2 7146 11500 0 Blue 0
2 AM Sun 34 34 N 2 7146 11500 0 Blue 0
3 AM Sun 34 34 N 2 7146 11500 0 Blue 0
4 AM Sun 34 34 N 2 7146 11500 0 Blue 0
5 AM Sun 35 35 N 2 7146 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