Detailed Predictions for: Elk Mountain
Launch Altitude (f): 4000
LZ Altitude (f): 1600
Sounding

Station:

 KOAK

Date/Time:

 4 FEB 2012

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)
4 AM Sat 38 38 E 7 2612 4000 0 Blue 0
5 AM Sat 38 38 E 7 2612 4000 0 Blue 0
6 AM Sat 38 38 E 7 2612 4000 0 Blue 0
7 AM Sat 39 39 E 7 2612 4000 0 Blue 0
8 AM Sat 41 41 E 7 2612 4000 0 Blue 0
9 AM Sat 43 43 E 7 2612 4000 0 Blue 0
10 AM Sat 46 47 E 6 2612 4000 0 Blue 0
11 AM Sat 49 51 E 6 3997 4000 0 Blue 2
12 Noon Sat 53 55 E 6 5081 4398 398 Blue 6
1 PM Sat 55 57 SE 6 5438 4888 888 Blue 8
2 PM Sat 56 58 SE 6 5617 5067 1067 Blue 9
3 PM Sat 56 57 SE 6 5438 4888 888 Blue 8
4 PM Sat 54 54 SE 6 4902 4000 0 Blue 5
5 PM Sat 51 51 SE 6 3997 4000 0 Blue 2
6 PM Sat 48 48 SE 6 2859 4000 0 Blue 0
7 PM Sat 45 45 E 5 2612 4000 0 Blue 0
8 PM Sat 43 43 E 5 2612 4000 0 Blue 0
9 PM Sat 42 42 E 5 2612 4000 0 Blue 0
10 PM Sat 41 41 E 5 2612 4000 0 Blue 0
11 PM Sat 41 41 E 5 2612 4000 0 Blue 0
12 Midnight Sun 40 40 E 5 2612 4000 0 Blue 0
1 AM Sun 39 39 NE 5 2612 4000 0 Blue 0
2 AM Sun 39 39 NE 5 2612 4000 0 Blue 0
3 AM Sun 39 39 NE 5 2612 4000 0 Blue 0
4 AM Sun 39 39 NE 3 2612 4000 0 Blue 0
5 AM Sun 39 39 NE 3 2612 4000 0 Blue 0
6 AM Sun 39 39 NE 3 2612 4000 0 Blue 0
7 AM Sun 40 40 NE 3 2612 4000 0 Blue 0
8 AM Sun 42 42 NE 3 2612 4000 0 Blue 0
9 AM Sun 45 45 NE 3 2612 4000 0 Blue 0
10 AM Sun 48 49 E 2 3166 4000 0 Blue 0
11 AM Sun 51 52 E 2 4422 4000 0 Blue 3
12 Noon Sun 54 56 E 2 5260 4710 710 Blue 7
1 PM Sun 56 58 S 3 5617 5067 1067 Blue 9
2 PM Sun 57 58 S 3 5617 5067 1067 Blue 9
3 PM Sun 57 58 S 3 5617 5067 1067 Blue 9
4 PM Sun 55 55 SE 5 5081 4398 398 Blue 6
5 PM Sun 52 52 SE 5 4422 4000 0 Blue 3
6 PM Sun 48 48 SE 5 2859 4000 0 Blue 0
7 PM Sun 45 45 SE 5 2612 4000 0 Blue 0
8 PM Sun 43 43 SE 5 2612 4000 0 Blue 0
9 PM Sun 43 43 SE 5 2612 4000 0 Blue 0
10 PM Sun 42 42 E 5 2612 4000 0 Blue 0
11 PM Sun 41 41 E 5 2612 4000 0 Blue 0
12 Midnight Mon 41 41 E 5 2612 4000 0 Blue 0
1 AM Mon 40 40 E 5 2612 4000 0 Blue 0
2 AM Mon 40 40 E 5 2612 4000 0 Blue 0
3 AM Mon 40 40 E 5 2612 4000 0 Blue 0
4 AM Mon 40 40 E 6 2612 4000 0 Blue 0
5 AM Mon 40 40 E 6 2612 4000 0 Blue 0
6 AM Mon 41 41 E 6 2612 4000 0 Blue 0
7 AM Mon 41 41 E 6 2612 4000 0 Blue 0
8 AM Mon 42 42 E 6 2612 4000 0 Blue 0
9 AM Mon 44 44 E 6 2612 4000 0 Blue 0
10 AM Mon 46 47 E 8 2612 4000 0 Blue 0
11 AM Mon 49 50 E 8 3564 4000 0 Blue 1
12 Noon Mon 52 53 E 8 4722 4000 0 Blue 4
1 PM Mon 54 55 E 8 5081 4398 398 Blue 6
2 PM Mon 55 56 E 8 5260 4710 710 Blue 7
3 PM Mon 54 54 E 8 4902 4000 0 Blue 5
4 PM Mon 52 52 SE 10 4422 4000 0 Blue 3
5 PM Mon 50 50 SE 10 3564 4000 0 Blue 1
6 PM Mon 47 47 SE 10 2612 4000 0 Blue 0
7 PM Mon 45 45 SE 10 2612 4000 0 Blue 0
8 PM Mon 45 45 SE 10 2612 4000 0 Blue 0
9 PM Mon 45 45 SE 10 2612 4000 0 Blue 0
10 PM Mon 45 45 E 7 2612 4000 0 Blue 0
11 PM Mon 45 45 E 7 2612 4000 0 Blue 0
12 Midnight Tue 45 45 E 7 2612 4000 0 Blue 0
1 AM Tue 45 45 E 7 2612 4000 0 Blue 0
2 AM Tue 45 45 E 7 2612 4000 0 Blue 0
3 AM Tue 45 45 E 7 2612 4000 0 Blue 0
4 AM Tue 45 45 E 8 2612 4000 0 Blue 0
5 AM Tue 45 45 E 8 2612 4000 0 Blue 0
6 AM Tue 44 44 E 8 2612 4000 0 Blue 0
7 AM Tue 43 43 E 8 2612 4000 0 Blue 0
8 AM Tue 42 42 E 8 2612 4000 0 Blue 0
9 AM Tue 41 41 E 8 2612 4000 0 Blue 0
10 AM Tue 41 41 E 6 2612 4000 0 Blue 0
11 AM Tue 41 41 E 6 2612 4000 0 Blue 0
12 Noon Tue 42 42 E 6 2612 4000 0 Blue 0
1 PM Tue 43 43 E 6 2612 4000 0 Blue 0
2 PM Tue 43 43 E 6 2612 4000 0 Blue 0
3 PM Tue 43 43 E 6 2612 4000 0 Blue 0
4 PM Tue 42 42 S 3 2612 4000 0 Blue 0
5 PM Tue 41 41 S 3 2612 4000 0 Blue 0
6 PM Tue 40 40 S 3 2612 4000 0 Blue 0
7 PM Tue 39 39 S 3 2612 4000 0 Blue 0
8 PM Tue 39 39 S 3 2612 4000 0 Blue 0
9 PM Tue 39 39 S 3 2612 4000 0 Blue 0
10 PM Tue 39 39 NE 1 2612 4000 0 Blue 0
11 PM Tue 39 39 NE 1 2612 4000 0 Blue 0
12 Midnight Wed 39 39 NE 1 2612 4000 0 Blue 0
1 AM Wed 38 38 NE 1 2612 4000 0 Blue 0
2 AM Wed 38 38 NE 1 2612 4000 0 Blue 0
3 AM Wed 38 38 NE 1 2612 4000 0 Blue 0
4 AM Wed 38 38 NE 2 2612 4000 0 Blue 0
5 AM Wed 38 38 NE 2 2612 4000 0 Blue 0
6 AM Wed 39 39 NE 2 2612 4000 0 Blue 0
7 AM Wed 39 39 NE 2 2612 4000 0 Blue 0
8 AM Wed 41 41 NE 2 2612 4000 0 Blue 0
9 AM Wed 43 43 NE 2 2612 4000 0 Blue 0
10 AM Wed 45 46 NW 2 2612 4000 0 Blue 0
11 AM Wed 48 49 NW 2 3166 4000 0 Blue 0
12 Noon Wed 51 53 NW 2 4722 4000 0 Blue 4
1 PM Wed 53 55 NW 2 5081 4398 398 Blue 6
2 PM Wed 54 55 NW 2 5081 4398 398 Blue 6
3 PM Wed 55 56 NW 2 5260 4710 710 Blue 7
4 PM Wed 55 55 W 3 5081 4398 398 Blue 6
5 PM Wed 52 52 W 3 4422 4000 0 Blue 3
6 PM Wed 49 49 W 3 3166 4000 0 Blue 0
7 PM Wed 46 46 W 3 2612 4000 0 Blue 0
8 PM Wed 45 45 W 3 2612 4000 0 Blue 0
9 PM Wed 45 45 W 3 2612 4000 0 Blue 0
10 PM Wed 45 45 NE 2 2612 4000 0 Blue 0
11 PM Wed 44 44 NE 2 2612 4000 0 Blue 0
12 Midnight Thu 44 44 NE 2 2612 4000 0 Blue 0
1 AM Thu 44 44 NE 2 2612 4000 0 Blue 0
2 AM Thu 43 43 NE 2 2612 4000 0 Blue 0
3 AM Thu 43 43 NE 2 2612 4000 0 Blue 0
4 AM Thu 42 42 NE 3 2612 4000 0 Blue 0
5 AM Thu 42 42 NE 3 2612 4000 0 Blue 0
6 AM Thu 42 42 NE 3 2612 4000 0 Blue 0
7 AM Thu 43 43 NE 3 2612 4000 0 Blue 0
8 AM Thu 44 44 NE 3 2612 4000 0 Blue 0
9 AM Thu 46 46 NE 3 2612 4000 0 Blue 0
10 AM Thu 49 50 NE 2 3564 4000 0 Blue 1
11 AM Thu 51 53 NE 2 4722 4000 0 Blue 4
12 Noon Thu 54 56 NE 2 5260 4710 710 Blue 7
1 PM Thu 56 58 NE 2 5617 5067 1067 Blue 9
2 PM Thu 57 59 NE 2 5795 5245 1245 Blue 10
3 PM Thu 57 58 NE 2 5617 5067 1067 Blue 9
4 PM Thu 56 56 W 5 5260 4710 710 Blue 7
5 PM Thu 54 54 W 5 4902 4000 0 Blue 5
6 PM Thu 50 50 W 5 3564 4000 0 Blue 1
7 PM Thu 48 48 W 5 2859 4000 0 Blue 0
8 PM Thu 46 46 W 5 2612 4000 0 Blue 0
9 PM Thu 45 45 W 5 2612 4000 0 Blue 0
10 PM Thu 44 44 E 2 2612 4000 0 Blue 0
11 PM Thu 44 44 E 2 2612 4000 0 Blue 0
12 Midnight Fri 43 43 E 2 2612 4000 0 Blue 0
1 AM Fri 43 43 E 2 2612 4000 0 Blue 0
2 AM Fri 43 43 E 2 2612 4000 0 Blue 0
3 AM Fri 43 43 E 2 2612 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 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