Detailed Predictions for: Elk Mountain
Launch Lat, Long, Altitude (f): 39.2820, -122.93, 4000
LZ Altitude (f): 1600
Sounding

Station:

 KOAK

Date/Time UTC:

 260911/1200

Temp/Wind data from:

NOAA Digital Forecast

Site Forecasts
Time
(Local)		 High
Temp
Puddle
Temp
Wind
 (mph)		 Wind
 Gust		 Thermal
Ceiling
(ft)		 Soaring
Ceiling
(ft)		 Above
Launch
(ft)		 Thermal
Type		 Thermal
Index
(F)
12 Midnight Fri 72 72 NNW 5 9 2585 4000 0 Blue 0
1 AM Fri 72 72 NNW 5 9 2585 4000 0 Blue 0
2 AM Fri 71 71 NNW 5 9 2585 4000 0 Blue 0
3 AM Fri 71 71 NNW 5 9 2585 4000 0 Blue 0
4 AM Fri 69 69 NNW 5 9 2585 4000 0 Blue 0
5 AM Fri 69 69 NNW 5 9 2585 4000 0 Blue 0
6 AM Fri 68 68 NNW 5 9 2585 4000 0 Blue 0
7 AM Fri 67 67 NNW 5 9 2585 4000 0 Blue 0
8 AM Fri 69 69 NNW 4 6 2585 4000 0 Blue 0
9 AM Fri 73 74 NNW 4 6 2585 4000 0 Blue 0
10 AM Fri 78 80 NNW 4 6 3626 4000 0 Blue 1
11 AM Fri 81 85 W 8 12 4752 4048 48 Blue 6
12 Noon Fri 83 88 W 8 12 7766 4733 733 Blue 9
1 PM Fri 84 90 W 8 12 8216 6515 2515 Blue 11
2 PM Fri 86 92 W 10 16 9039 7864 3864 Blue 12
3 PM Fri 86 91 W 10 16 8570 7751 3751 Blue 11
4 PM Fri 86 89 W 10 16 7893 5744 1744 Blue 10
5 PM Fri 84 86 W 10 16 5932 4263 263 Blue 7
6 PM Fri 81 81 W 10 16 3841 4000 0 Blue 2
7 PM Fri 75 75 W 10 16 2585 4000 0 Blue 0
8 PM Fri 66 66 NW 5 9 2585 4000 0 Blue 0
9 PM Fri 65 65 NW 5 9 2585 4000 0 Blue 0
10 PM Fri 66 66 NW 5 9 2585 4000 0 Blue 0
11 PM Fri 67 67 NNW 6 10 2585 4000 0 Blue 0
12 Midnight Sat 66 66 NNW 6 10 2585 4000 0 Blue 0
1 AM Sat 66 66 NNW 6 10 2585 4000 0 Blue 0
2 AM Sat 65 65 NNW 6 10 2585 4000 0 Blue 0
3 AM Sat 64 64 NNW 6 10 2585 4000 0 Blue 0
4 AM Sat 63 63 NNW 6 10 2585 4000 0 Blue 0
5 AM Sat 63 63 NW 6 10 2585 4000 0 Blue 0
6 AM Sat 62 62 NW 6 10 2585 4000 0 Blue 0
7 AM Sat 61 61 NW 6 10 2585 4000 0 Blue 0
8 AM Sat 63 63 WNW 8 16 2585 4000 0 Blue 0
9 AM Sat 65 66 WNW 8 16 2585 4000 0 Blue 0
10 AM Sat 68 70 WNW 8 16 2585 4000 0 Blue 0
11 AM Sat 70 74 W 10 16 2585 4000 0 Blue 0
12 Noon Sat 70 75 W 10 16 2585 4000 0 Blue 0
1 PM Sat 72 77 W 10 16 2807 4000 0 Blue 0
2 PM Sat 72 77 W 12 19 2807 4000 0 Blue 0
3 PM Sat 72 76 W 12 19 2585 4000 0 Blue 0
4 PM Sat 72 75 W 12 19 2585 4000 0 Blue 0
5 PM Sat 68 69 W 13 21 2585 4000 0 Blue 0
6 PM Sat 65 65 W 13 21 2585 4000 0 Blue 0
7 PM Sat 59 59 W 13 21 2585 4000 0 Blue 0
8 PM Sat 53 53 WNW 16 25 2585 4000 0 Blue 0
9 PM Sat 51 51 WNW 16 25 2585 4000 0 Blue 0
10 PM Sat 51 51 WNW 16 25 2585 4000 0 Blue 0
11 PM Sat 52 52 WNW 13 21 2585 4000 0 Blue 0
12 Midnight Sun 51 51 WNW 13 21 2585 4000 0 Blue 0
1 AM Sun 51 51 WNW 13 21 2585 4000 0 Blue 0
2 AM Sun 50 50 NW 11 18 2585 4000 0 Blue 0
3 AM Sun 49 49 NW 11 18 2585 4000 0 Blue 0
4 AM Sun 48 48 NW 11 18 2585 4000 0 Blue 0
5 AM Sun 48 48 NNW 8 12 2585 4000 0 Blue 0
6 AM Sun 47 47 NNW 8 12 2585 4000 0 Blue 0
7 AM Sun 48 48 NNW 8 12 2585 4000 0 Blue 0
8 AM Sun 50 50 NNW 6 10 2585 4000 0 Blue 0
9 AM Sun 55 56 NNW 6 10 2585 4000 0 Blue 0
10 AM Sun 61 63 NNW 6 10 2585 4000 0 Blue 0
11 AM Sun 66 70 W 5 9 2585 4000 0 Blue 0
12 Noon Sun 69 74 W 5 9 2585 4000 0 Blue 0
1 PM Sun 71 77 W 5 9 2807 4000 0 Blue 0
2 PM Sun 72 78 W 8 12 3096 4000 0 Blue 0
3 PM Sun 73 78 W 8 12 3096 4000 0 Blue 0
4 PM Sun 73 76 W 8 12 2585 4000 0 Blue 0
5 PM Sun 71 73 W 6 17 2585 4000 0 Blue 0
6 PM Sun 66 66 W 6 17 2585 4000 0 Blue 0
7 PM Sun 61 61 W 6 17 2585 4000 0 Blue 0
8 PM Sun 57 57 NW 3 10 2585 4000 0 Blue 0
9 PM Sun 56 56 NW 3 10 2585 4000 0 Blue 0
10 PM Sun 57 57 NW 3 10 2585 4000 0 Blue 0
11 PM Sun 58 58 NNW 4 10 2585 4000 0 Blue 0
12 Midnight Mon 58 58 NNW 4 10 2585 4000 0 Blue 0
1 AM Mon 58 58 NNW 4 10 2585 4000 0 Blue 0
2 AM Mon 58 58 N 4 8 2585 4000 0 Blue 0
3 AM Mon 57 57 N 4 8 2585 4000 0 Blue 0
4 AM Mon 57 57 N 4 8 2585 4000 0 Blue 0
5 AM Mon 56 56 N 3 6 2585 4000 0 Blue 0
6 AM Mon 56 56 N 3 6 2585 4000 0 Blue 0
7 AM Mon 57 57 N 3 6 2585 4000 0 Blue 0
8 AM Mon 59 59 NNE 3 5 2585 4000 0 Blue 0
9 AM Mon 63 64 NNE 3 5 2585 4000 0 Blue 0
10 AM Mon 69 71 NNE 3 5 2585 4000 0 Blue 0
11 AM Mon 74 78 SW 3 5 3096 4000 0 Blue 0
12 Noon Mon 77 82 SW 3 5 4057 4000 0 Blue 3
1 PM Mon 79 85 SW 3 5 4752 4048 48 Blue 6
2 PM Mon 79 84 WSW 5 12 4465 4000 0 Blue 5
3 PM Mon 81 86 WSW 5 12 5932 4263 263 Blue 7
4 PM Mon 81 84 WSW 5 12 4465 4000 0 Blue 5
5 PM Mon 78 80 W 6 14 3626 4000 0 Blue 1
6 PM Mon 71 71 W 6 14 2585 4000 0 Blue 0
7 PM Mon 65 65 W 6 14 2585 4000 0 Blue 0
8 PM Mon 61 61 WNW 4 8 2585 4000 0 Blue 0
9 PM Mon 60 60 WNW 4 8 2585 4000 0 Blue 0
10 PM Mon 61 61 WNW 4 8 2585 4000 0 Blue 0
11 PM Mon 62 62 N 4 8 2585 4000 0 Blue 0
12 Midnight Tue 62 62 N 4 8 2585 4000 0 Blue 0
1 AM Tue 61 61 N 4 8 2585 4000 0 Blue 0
2 AM Tue 61 61 N 3 6 2585 4000 0 Blue 0
3 AM Tue 61 61 N 3 6 2585 4000 0 Blue 0
4 AM Tue 61 61 N 3 6 2585 4000 0 Blue 0
5 AM Tue 61 61 NNE 2 5 2585 4000 0 Blue 0
6 AM Tue 60 60 NNE 2 5 2585 4000 0 Blue 0
7 AM Tue 61 61 NNE 2 5 2585 4000 0 Blue 0
8 AM Tue 62 62 ENE 3 6 2585 4000 0 Blue 0
9 AM Tue 66 67 ENE 3 6 2585 4000 0 Blue 0
10 AM Tue 72 74 ENE 3 6 2585 4000 0 Blue 0
11 AM Tue 77 81 S 3 8 3841 4000 0 Blue 2
12 Noon Tue 80 85 S 3 8 4752 4048 48 Blue 6
1 PM Tue 81 87 S 3 8 6537 4455 455 Blue 8
2 PM Tue 82 87 SW 5 13 6537 4455 455 Blue 8
3 PM Tue 83 88 SW 5 13 7766 4733 733 Blue 9
4 PM Tue 82 85 SW 5 13 4752 4048 48 Blue 6
5 PM Tue 80 81 WSW 6 16 3841 4000 0 Blue 2
6 PM Tue 75 75 WSW 6 16 2585 4000 0 Blue 0
7 PM Tue 68 68 WSW 6 16 2585 4000 0 Blue 0
8 PM Tue 63 63 W 3 5 2585 4000 0 Blue 0
9 PM Tue 62 62 W 3 5 2585 4000 0 Blue 0
10 PM Tue 63 63 W 3 5 2585 4000 0 Blue 0
11 PM Tue 64 64 N 3 5 2585 4000 0 Blue 0
12 Midnight Wed 64 64 N 3 5 2585 4000 0 Blue 0
1 AM Wed 63 63 N 3 5 2585 4000 0 Blue 0
2 AM Wed 62 62 NE 2 5 2585 4000 0 Blue 0
3 AM Wed 61 61 NE 2 5 2585 4000 0 Blue 0
4 AM Wed 61 61 NE 2 5 2585 4000 0 Blue 0
5 AM Wed 61 61 ENE 2 5 2585 4000 0 Blue 0
6 AM Wed 61 61 ENE 2 5 2585 4000 0 Blue 0
7 AM Wed 62 62 ENE 2 5 2585 4000 0 Blue 0
8 AM Wed 64 64 ENE 2 5 2585 4000 0 Blue 0
9 AM Wed 67 68 ENE 2 5 2585 4000 0 Blue 0
10 AM Wed 71 73 ENE 2 5 2585 4000 0 Blue 0
11 AM Wed 75 79 S 4 9 3382 4000 0 Blue 0
12 Noon Wed 77 82 S 4 9 4057 4000 0 Blue 3
1 PM Wed 79 85 S 4 9 4752 4048 48 Blue 6
2 PM Wed 80 86 SSW 5 13 5932 4263 263 Blue 7
3 PM Wed 81 86 SSW 5 13 5932 4263 263 Blue 7
4 PM Wed 81 84 SSW 5 13 4465 4000 0 Blue 5
5 PM Wed 79 81 SW 6 14 3841 4000 0 Blue 2
6 PM Wed 74 74 SW 6 14 2585 4000 0 Blue 0
7 PM Wed 68 68 SW 6 14 2585 4000 0 Blue 0
8 PM Wed 63 63 W 3 5 2585 4000 0 Blue 0
9 PM Wed 62 62 W 3 5 2585 4000 0 Blue 0
10 PM Wed 62 62 W 3 5 2585 4000 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 or WeatherAPI.com website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the National Weather Service or WeatherAPI.com 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 or WeatherAPI.com website.

Wind Gust: This estimate is taken from the National Weather Service or WeatherAPI.com 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 [email protected]