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

Station:

 KOAK

Date/Time:

 N/A

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 Mon 74 74 N 6 9 N/A N/A N/A N/A N/A
1 AM Mon 75 75 N 6 9 N/A N/A N/A N/A N/A
2 AM Mon 75 75 N 6 9 N/A N/A N/A N/A N/A
3 AM Mon 75 75 N 6 9 N/A N/A N/A N/A N/A
4 AM Mon 74 74 N 6 9 N/A N/A N/A N/A N/A
5 AM Mon 74 74 N 8 9 N/A N/A N/A N/A N/A
6 AM Mon 73 73 N 8 9 N/A N/A N/A N/A N/A
7 AM Mon 72 72 N 8 9 N/A N/A N/A N/A N/A
8 AM Mon 74 74 N 6 9 N/A N/A N/A N/A N/A
9 AM Mon 78 78 N 6 9 N/A N/A N/A N/A N/A
10 AM Mon 85 86 N 6 9 N/A N/A N/A N/A N/A
11 AM Mon 88 91 WSW 4 11 N/A N/A N/A N/A N/A
12 Noon Mon 90 94 WSW 4 11 N/A N/A N/A N/A N/A
1 PM Mon 91 95 WSW 4 11 N/A N/A N/A N/A N/A
2 PM Mon 91 95 W 8 13 N/A N/A N/A N/A N/A
3 PM Mon 91 94 W 8 13 N/A N/A N/A N/A N/A
4 PM Mon 92 94 W 8 13 N/A N/A N/A N/A N/A
5 PM Mon 90 91 NW 8 14 N/A N/A N/A N/A N/A
6 PM Mon 86 86 NW 8 14 N/A N/A N/A N/A N/A
7 PM Mon 80 80 NW 8 14 N/A N/A N/A N/A N/A
8 PM Mon 73 73 N 9 12 N/A N/A N/A N/A N/A
9 PM Mon 74 74 N 9 12 N/A N/A N/A N/A N/A
10 PM Mon 73 73 N 9 12 N/A N/A N/A N/A N/A
11 PM Mon 73 73 N 8 11 N/A N/A N/A N/A N/A
12 Midnight Tue 72 72 N 8 11 N/A N/A N/A N/A N/A
1 AM Tue 72 72 N 8 11 N/A N/A N/A N/A N/A
2 AM Tue 72 72 N 6 10 N/A N/A N/A N/A N/A
3 AM Tue 71 71 N 6 10 N/A N/A N/A N/A N/A
4 AM Tue 70 70 N 6 10 N/A N/A N/A N/A N/A
5 AM Tue 70 70 N 6 10 N/A N/A N/A N/A N/A
6 AM Tue 68 68 N 6 10 N/A N/A N/A N/A N/A
7 AM Tue 69 69 N 6 10 N/A N/A N/A N/A N/A
8 AM Tue 70 70 N 5 8 N/A N/A N/A N/A N/A
9 AM Tue 74 74 N 5 8 N/A N/A N/A N/A N/A
10 AM Tue 81 83 N 5 8 N/A N/A N/A N/A N/A
11 AM Tue 84 87 W 4 8 N/A N/A N/A N/A N/A
12 Noon Tue 85 89 W 4 8 N/A N/A N/A N/A N/A
1 PM Tue 86 90 W 4 8 N/A N/A N/A N/A N/A
2 PM Tue 86 90 W 6 12 N/A N/A N/A N/A N/A
3 PM Tue 87 90 W 6 12 N/A N/A N/A N/A N/A
4 PM Tue 86 88 W 6 12 N/A N/A N/A N/A N/A
5 PM Tue 84 85 W 6 12 N/A N/A N/A N/A N/A
6 PM Tue 78 78 W 6 12 N/A N/A N/A N/A N/A
7 PM Tue 71 71 W 6 12 N/A N/A N/A N/A N/A
8 PM Tue 66 66 NW 4 10 N/A N/A N/A N/A N/A
9 PM Tue 65 65 NW 4 10 N/A N/A N/A N/A N/A
10 PM Tue 65 65 NW 4 10 N/A N/A N/A N/A N/A
11 PM Tue 66 66 NNW 5 11 N/A N/A N/A N/A N/A
12 Midnight Wed 66 66 NNW 5 11 N/A N/A N/A N/A N/A
1 AM Wed 65 65 NNW 5 11 N/A N/A N/A N/A N/A
2 AM Wed 65 65 NNW 4 9 N/A N/A N/A N/A N/A
3 AM Wed 64 64 NNW 4 9 N/A N/A N/A N/A N/A
4 AM Wed 64 64 NNW 4 9 N/A N/A N/A N/A N/A
5 AM Wed 63 63 N 5 9 N/A N/A N/A N/A N/A
6 AM Wed 62 62 N 5 9 N/A N/A N/A N/A N/A
7 AM Wed 61 61 N 5 9 N/A N/A N/A N/A N/A
8 AM Wed 62 62 N 4 8 N/A N/A N/A N/A N/A
9 AM Wed 66 66 N 4 8 N/A N/A N/A N/A N/A
10 AM Wed 72 73 N 4 8 N/A N/A N/A N/A N/A
11 AM Wed 77 79 WNW 4 8 N/A N/A N/A N/A N/A
12 Noon Wed 80 83 WNW 4 8 N/A N/A N/A N/A N/A
1 PM Wed 81 84 WNW 4 8 N/A N/A N/A N/A N/A
2 PM Wed 81 83 W 6 11 N/A N/A N/A N/A N/A
3 PM Wed 82 84 W 6 11 N/A N/A N/A N/A N/A
4 PM Wed 81 82 W 6 11 N/A N/A N/A N/A N/A
5 PM Wed 79 79 W 5 12 N/A N/A N/A N/A N/A
6 PM Wed 74 74 W 5 12 N/A N/A N/A N/A N/A
7 PM Wed 68 68 W 5 12 N/A N/A N/A N/A N/A
8 PM Wed 64 64 NW 3 8 N/A N/A N/A N/A N/A
9 PM Wed 63 63 NW 3 8 N/A N/A N/A N/A N/A
10 PM Wed 65 65 NW 3 8 N/A N/A N/A N/A N/A
11 PM Wed 66 66 N 3 6 N/A N/A N/A N/A N/A
12 Midnight Thu 66 66 N 3 6 N/A N/A N/A N/A N/A
1 AM Thu 65 65 N 3 6 N/A N/A N/A N/A N/A
2 AM Thu 65 65 N 2 6 N/A N/A N/A N/A N/A
3 AM Thu 65 65 N 2 6 N/A N/A N/A N/A N/A
4 AM Thu 65 65 N 2 6 N/A N/A N/A N/A N/A
5 AM Thu 65 65 N 2 4 N/A N/A N/A N/A N/A
6 AM Thu 65 65 N 2 4 N/A N/A N/A N/A N/A
7 AM Thu 65 65 N 2 4 N/A N/A N/A N/A N/A
8 AM Thu 65 65 NE 2 3 N/A N/A N/A N/A N/A
9 AM Thu 68 68 NE 2 3 N/A N/A N/A N/A N/A
10 AM Thu 72 72 NE 2 3 N/A N/A N/A N/A N/A
11 AM Thu 76 77 SSW 3 6 N/A N/A N/A N/A N/A
12 Noon Thu 78 80 SSW 3 6 N/A N/A N/A N/A N/A
1 PM Thu 80 82 SSW 3 6 N/A N/A N/A N/A N/A
2 PM Thu 80 82 SW 5 10 N/A N/A N/A N/A N/A
3 PM Thu 81 83 SW 5 10 N/A N/A N/A N/A N/A
4 PM Thu 81 82 SW 5 10 N/A N/A N/A N/A N/A
5 PM Thu 79 79 W 4 11 N/A N/A N/A N/A N/A
6 PM Thu 75 75 W 4 11 N/A N/A N/A N/A N/A
7 PM Thu 69 69 W 4 11 N/A N/A N/A N/A N/A
8 PM Thu 64 64 W 4 11 N/A N/A N/A N/A N/A
9 PM Thu 63 63 W 4 11 N/A N/A N/A N/A N/A
10 PM Thu 63 63 W 4 11 N/A N/A N/A N/A N/A
11 PM Thu 64 64 N 2 5 N/A N/A N/A N/A N/A
12 Midnight Fri 64 64 N 2 5 N/A N/A N/A N/A N/A
1 AM Fri 64 64 N 2 5 N/A N/A N/A N/A N/A
2 AM Fri 63 63 N 2 5 N/A N/A N/A N/A N/A
3 AM Fri 63 63 N 2 5 N/A N/A N/A N/A N/A
4 AM Fri 62 62 N 2 5 N/A N/A N/A N/A N/A
5 AM Fri 62 62 NE 2 4 N/A N/A N/A N/A N/A
6 AM Fri 62 62 NE 2 4 N/A N/A N/A N/A N/A
7 AM Fri 62 62 NE 2 4 N/A N/A N/A N/A N/A
8 AM Fri 63 63 NE 2 4 N/A N/A N/A N/A N/A
9 AM Fri 65 65 NE 2 4 N/A N/A N/A N/A N/A
10 AM Fri 68 68 NE 2 4 N/A N/A N/A N/A N/A
11 AM Fri 71 72 SW 6 12 N/A N/A N/A N/A N/A
12 Noon Fri 73 75 SW 6 12 N/A N/A N/A N/A N/A
1 PM Fri 74 76 SW 6 12 N/A N/A N/A N/A N/A
2 PM Fri 75 77 SW 6 12 N/A N/A N/A N/A N/A
3 PM Fri 75 77 SW 6 12 N/A N/A N/A N/A N/A
4 PM Fri 75 76 SW 6 12 N/A N/A N/A N/A N/A
5 PM Fri 74 74 SW 4 12 N/A N/A N/A N/A N/A
6 PM Fri 70 70 SW 4 12 N/A N/A N/A N/A N/A
7 PM Fri 64 64 SW 4 12 N/A N/A N/A N/A N/A
8 PM Fri 60 60 SW 4 12 N/A N/A N/A N/A N/A
9 PM Fri 59 59 SW 4 12 N/A N/A N/A N/A N/A
10 PM Fri 60 60 SW 4 12 N/A N/A N/A N/A N/A
11 PM Fri 61 61 WSW 2 8 N/A N/A N/A N/A N/A
12 Midnight Sat 61 61 WSW 2 8 N/A N/A N/A N/A N/A
1 AM Sat 61 61 WSW 2 8 N/A N/A N/A N/A N/A
2 AM Sat 61 61 WSW 2 8 N/A N/A N/A N/A N/A
3 AM Sat 61 61 WSW 2 8 N/A N/A N/A N/A N/A
4 AM Sat 60 60 WSW 2 8 N/A N/A N/A N/A N/A
5 AM Sat 60 60 SW 2 5 N/A N/A N/A N/A N/A
6 AM Sat 59 59 SW 2 5 N/A N/A N/A N/A N/A
7 AM Sat 59 59 SW 2 5 N/A N/A N/A N/A N/A
8 AM Sat 59 59 SW 2 5 N/A N/A N/A N/A N/A
9 AM Sat 62 62 SW 2 5 N/A N/A N/A N/A N/A
10 AM Sat 64 64 SW 2 5 N/A N/A N/A N/A N/A
11 AM Sat 67 68 S 4 9 N/A N/A N/A N/A N/A
12 Noon Sat 68 70 S 4 9 N/A N/A N/A N/A N/A
1 PM Sat 69 71 S 4 9 N/A N/A N/A N/A N/A
2 PM Sat 69 71 S 4 9 N/A N/A N/A N/A N/A
3 PM Sat 70 71 S 4 9 N/A N/A N/A N/A N/A
4 PM Sat 71 72 S 4 9 N/A N/A N/A N/A N/A
5 PM Sat 70 70 SW 3 9 N/A N/A N/A N/A N/A
6 PM Sat 66 66 SW 3 9 N/A N/A N/A N/A N/A
7 PM Sat 61 61 SW 3 9 N/A N/A N/A N/A N/A
8 PM Sat 58 58 SW 3 9 N/A N/A N/A N/A N/A
9 PM Sat 58 58 SW 3 9 N/A N/A N/A N/A N/A
10 PM Sat 60 60 SW 3 9 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 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]