Detailed Predictions for: Chelan
Launch Altitude (f): 3820
LZ Altitude (f): 1200
Sounding

Station:

 KGEG

Date/Time:

 N/A

Temp/Wind data from:

NOAA Digital Forecast

Time
(Local)		 High
Temp
Puddle
Temp
Wind
 (mph)		 Thermal
Ceiling
(ft)		 Soaring
Ceiling
(ft)		 Above
Launch
(ft)		 Thermal
Type		 Thermal
Index
(F)
12 Midnight Mon 54 54 NNW 5 N/A N/A N/A N/A N/A
1 AM Mon 54 54 NNW 5 N/A N/A N/A N/A N/A
2 AM Mon 52 52 NW 6 N/A N/A N/A N/A N/A
3 AM Mon 51 51 NW 6 N/A N/A N/A N/A N/A
4 AM Mon 48 48 NW 6 N/A N/A N/A N/A N/A
5 AM Mon 46 46 WNW 7 N/A N/A N/A N/A N/A
6 AM Mon 45 45 WNW 7 N/A N/A N/A N/A N/A
7 AM Mon 45 45 WNW 7 N/A N/A N/A N/A N/A
8 AM Mon 49 49 WNW 5 N/A N/A N/A N/A N/A
9 AM Mon 54 55 WNW 5 N/A N/A N/A N/A N/A
10 AM Mon 61 63 WNW 5 N/A N/A N/A N/A N/A
11 AM Mon 68 71 E 2 N/A N/A N/A N/A N/A
12 Noon Mon 73 76 E 2 N/A N/A N/A N/A N/A
1 PM Mon 76 80 E 2 N/A N/A N/A N/A N/A
2 PM Mon 79 82 ESE 4 N/A N/A N/A N/A N/A
3 PM Mon 80 83 ESE 4 N/A N/A N/A N/A N/A
4 PM Mon 80 82 ESE 4 N/A N/A N/A N/A N/A
5 PM Mon 79 80 NNE 4 N/A N/A N/A N/A N/A
6 PM Mon 76 76 NNE 4 N/A N/A N/A N/A N/A
7 PM Mon 71 71 NNE 4 N/A N/A N/A N/A N/A
8 PM Mon 66 66 NNE 4 N/A N/A N/A N/A N/A
9 PM Mon 64 64 NNE 4 N/A N/A N/A N/A N/A
10 PM Mon 63 63 NNE 4 N/A N/A N/A N/A N/A
11 PM Mon 62 62 WNW 6 N/A N/A N/A N/A N/A
12 Midnight Tue 60 60 WNW 6 N/A N/A N/A N/A N/A
1 AM Tue 59 59 WNW 6 N/A N/A N/A N/A N/A
2 AM Tue 58 58 WNW 6 N/A N/A N/A N/A N/A
3 AM Tue 56 56 WNW 6 N/A N/A N/A N/A N/A
4 AM Tue 55 55 WNW 6 N/A N/A N/A N/A N/A
5 AM Tue 53 53 WNW 7 N/A N/A N/A N/A N/A
6 AM Tue 52 52 WNW 7 N/A N/A N/A N/A N/A
7 AM Tue 52 52 WNW 7 N/A N/A N/A N/A N/A
8 AM Tue 55 55 WNW 7 N/A N/A N/A N/A N/A
9 AM Tue 60 61 WNW 7 N/A N/A N/A N/A N/A
10 AM Tue 66 68 WNW 7 N/A N/A N/A N/A N/A
11 AM Tue 72 75 WNW 13 N/A N/A N/A N/A N/A
12 Noon Tue 76 80 WNW 13 N/A N/A N/A N/A N/A
1 PM Tue 79 83 WNW 13 N/A N/A N/A N/A N/A
2 PM Tue 81 85 WNW 13 N/A N/A N/A N/A N/A
3 PM Tue 82 85 WNW 13 N/A N/A N/A N/A N/A
4 PM Tue 82 84 WNW 13 N/A N/A N/A N/A N/A
5 PM Tue 81 82 WNW 13 N/A N/A N/A N/A N/A
6 PM Tue 77 77 WNW 13 N/A N/A N/A N/A N/A
7 PM Tue 71 71 WNW 13 N/A N/A N/A N/A N/A
8 PM Tue 66 66 WNW 13 N/A N/A N/A N/A N/A
9 PM Tue 64 64 WNW 13 N/A N/A N/A N/A N/A
10 PM Tue 62 62 WNW 13 N/A N/A N/A N/A N/A
11 PM Tue 61 61 NNW 8 N/A N/A N/A N/A N/A
12 Midnight Wed 59 59 NNW 8 N/A N/A N/A N/A N/A
1 AM Wed 58 58 NNW 8 N/A N/A N/A N/A N/A
2 AM Wed 56 56 NNW 8 N/A N/A N/A N/A N/A
3 AM Wed 55 55 NNW 8 N/A N/A N/A N/A N/A
4 AM Wed 53 53 NNW 8 N/A N/A N/A N/A N/A
5 AM Wed 52 52 NW 5 N/A N/A N/A N/A N/A
6 AM Wed 50 50 NW 5 N/A N/A N/A N/A N/A
7 AM Wed 50 50 NW 5 N/A N/A N/A N/A N/A
8 AM Wed 53 53 NW 5 N/A N/A N/A N/A N/A
9 AM Wed 57 58 NW 5 N/A N/A N/A N/A N/A
10 AM Wed 62 64 NW 5 N/A N/A N/A N/A N/A
11 AM Wed 68 71 NE 6 N/A N/A N/A N/A N/A
12 Noon Wed 72 76 NE 6 N/A N/A N/A N/A N/A
1 PM Wed 74 78 NE 6 N/A N/A N/A N/A N/A
2 PM Wed 76 80 NE 6 N/A N/A N/A N/A N/A
3 PM Wed 77 80 NE 6 N/A N/A N/A N/A N/A
4 PM Wed 77 79 NE 6 N/A N/A N/A N/A N/A
5 PM Wed 76 77 ENE 4 N/A N/A N/A N/A N/A
6 PM Wed 73 73 ENE 4 N/A N/A N/A N/A N/A
7 PM Wed 67 67 ENE 4 N/A N/A N/A N/A N/A
8 PM Wed 62 62 ENE 4 N/A N/A N/A N/A N/A
9 PM Wed 60 60 ENE 4 N/A N/A N/A N/A N/A
10 PM Wed 58 58 ENE 4 N/A N/A N/A N/A N/A
11 PM Wed 57 57 NNW 4 N/A N/A N/A N/A N/A
12 Midnight Thu 56 56 NNW 4 N/A N/A N/A N/A N/A
1 AM Thu 55 55 NNW 4 N/A N/A N/A N/A N/A
2 AM Thu 53 53 NNW 4 N/A N/A N/A N/A N/A
3 AM Thu 52 52 NNW 4 N/A N/A N/A N/A N/A
4 AM Thu 50 50 NNW 4 N/A N/A N/A N/A N/A
5 AM Thu 49 49 NNW 4 N/A N/A N/A N/A N/A
6 AM Thu 47 47 NNW 4 N/A N/A N/A N/A N/A
7 AM Thu 47 47 NNW 4 N/A N/A N/A N/A N/A
8 AM Thu 51 51 NNW 4 N/A N/A N/A N/A N/A
9 AM Thu 56 57 NNW 4 N/A N/A N/A N/A N/A
10 AM Thu 62 64 NNW 4 N/A N/A N/A N/A N/A
11 AM Thu 70 74 SSE 5 N/A N/A N/A N/A N/A
12 Noon Thu 74 78 SSE 5 N/A N/A N/A N/A N/A
1 PM Thu 78 83 SSE 5 N/A N/A N/A N/A N/A
2 PM Thu 80 85 SSE 5 N/A N/A N/A N/A N/A
3 PM Thu 81 85 SSE 5 N/A N/A N/A N/A N/A
4 PM Thu 81 83 SSE 5 N/A N/A N/A N/A N/A
5 PM Thu 80 81 S 5 N/A N/A N/A N/A N/A
6 PM Thu 77 77 S 5 N/A N/A N/A N/A N/A
7 PM Thu 71 71 S 5 N/A N/A N/A N/A N/A
8 PM Thu 66 66 S 5 N/A N/A N/A N/A N/A
9 PM Thu 64 64 S 5 N/A N/A N/A N/A N/A
10 PM Thu 62 62 S 5 N/A N/A N/A N/A N/A
11 PM Thu 61 61 WNW 5 N/A N/A N/A N/A N/A
12 Midnight Fri 60 60 WNW 5 N/A N/A N/A N/A N/A
1 AM Fri 59 59 WNW 5 N/A N/A N/A N/A N/A
2 AM Fri 57 57 WNW 5 N/A N/A N/A N/A N/A
3 AM Fri 56 56 WNW 5 N/A N/A N/A N/A N/A
4 AM Fri 54 54 WNW 5 N/A N/A N/A N/A N/A
5 AM Fri 53 53 WNW 5 N/A N/A N/A N/A N/A
6 AM Fri 51 51 WNW 5 N/A N/A N/A N/A N/A
7 AM Fri 51 51 WNW 5 N/A N/A N/A N/A N/A
8 AM Fri 54 54 WNW 5 N/A N/A N/A N/A N/A
9 AM Fri 59 60 WNW 5 N/A N/A N/A N/A N/A
10 AM Fri 65 67 WNW 5 N/A N/A N/A N/A N/A
11 AM Fri 71 74 W 10 N/A N/A N/A N/A N/A
12 Noon Fri 75 79 W 10 N/A N/A N/A N/A N/A
1 PM Fri 78 82 W 10 N/A N/A N/A N/A N/A
2 PM Fri 80 84 W 10 N/A N/A N/A N/A N/A
3 PM Fri 81 84 W 10 N/A N/A N/A N/A N/A
4 PM Fri 81 83 W 10 N/A N/A N/A N/A N/A
5 PM Fri 80 81 W 12 N/A N/A N/A N/A N/A
6 PM Fri 76 76 W 12 N/A N/A N/A N/A N/A
7 PM Fri 71 71 W 12 N/A N/A N/A N/A N/A
8 PM Fri 66 66 W 12 N/A N/A N/A N/A N/A
9 PM Fri 64 64 W 12 N/A N/A N/A N/A N/A
10 PM Fri 62 62 W 12 N/A N/A N/A N/A N/A
11 PM Fri 61 61 WNW 7 N/A N/A N/A N/A N/A
12 Midnight Sat 59 59 WNW 7 N/A N/A N/A N/A N/A
1 AM Sat 58 58 WNW 7 N/A N/A N/A N/A N/A
2 AM Sat 56 56 WNW 7 N/A N/A N/A N/A N/A
3 AM Sat 55 55 WNW 7 N/A N/A N/A N/A N/A
4 AM Sat 53 53 WNW 7 N/A N/A N/A N/A N/A
5 AM Sat 52 52 WNW 7 N/A N/A N/A N/A N/A
6 AM Sat 50 50 WNW 7 N/A N/A N/A N/A N/A
7 AM Sat 50 50 WNW 7 N/A N/A N/A N/A N/A
8 AM Sat 53 53 WNW 7 N/A N/A N/A N/A N/A
9 AM Sat 58 59 WNW 7 N/A N/A N/A N/A N/A
10 AM Sat 63 65 WNW 7 N/A N/A N/A N/A N/A
11 AM Sat 69 72 NNW 5 N/A N/A N/A N/A N/A
12 Noon Sat 73 76 NNW 5 N/A N/A N/A N/A N/A
1 PM Sat 76 80 NNW 5 N/A N/A N/A N/A N/A
2 PM Sat 78 81 NNW 5 N/A N/A N/A N/A N/A
3 PM Sat 79 82 NNW 5 N/A N/A N/A N/A N/A
4 PM Sat 79 81 NNW 5 N/A N/A N/A N/A N/A

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 Weather Channel website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the Weather Channel 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 Weather Channel 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