Detailed Predictions for: Elk Mountain
Launch Altitude (f): 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)
Thermal
Ceiling

(ft)
Soaring
Ceiling

(ft)
Above
Launch

(ft)
Thermal
Type
Thermal
Index

(F)
4 AM Thu 43 43 SW 18 N/A N/A N/A N/A N/A
5 AM Thu 42 42 SW 18 N/A N/A N/A N/A N/A
6 AM Thu 41 41 SW 18 N/A N/A N/A N/A N/A
7 AM Thu 41 41 SW 18 N/A N/A N/A N/A N/A
8 AM Thu 41 41 SW 18 N/A N/A N/A N/A N/A
9 AM Thu 41 41 SW 18 N/A N/A N/A N/A N/A
10 AM Thu 41 41 SW 15 N/A N/A N/A N/A N/A
11 AM Thu 43 43 SW 15 N/A N/A N/A N/A N/A
12 Noon Thu 44 44 SW 15 N/A N/A N/A N/A N/A
1 PM Thu 45 45 W 17 N/A N/A N/A N/A N/A
2 PM Thu 45 45 W 17 N/A N/A N/A N/A N/A
3 PM Thu 44 44 W 17 N/A N/A N/A N/A N/A
4 PM Thu 43 43 W 12 N/A N/A N/A N/A N/A
5 PM Thu 42 42 W 12 N/A N/A N/A N/A N/A
6 PM Thu 41 41 W 12 N/A N/A N/A N/A N/A
7 PM Thu 40 40 W 10 N/A N/A N/A N/A N/A
8 PM Thu 39 39 W 10 N/A N/A N/A N/A N/A
9 PM Thu 38 38 W 10 N/A N/A N/A N/A N/A
10 PM Thu 38 38 W 6 N/A N/A N/A N/A N/A
11 PM Thu 38 38 W 6 N/A N/A N/A N/A N/A
12 Midnight Fri 38 38 W 6 N/A N/A N/A N/A N/A
1 AM Fri 38 38 SW 5 N/A N/A N/A N/A N/A
2 AM Fri 38 38 SW 5 N/A N/A N/A N/A N/A
3 AM Fri 38 38 SW 5 N/A N/A N/A N/A N/A
4 AM Fri 38 38 S 5 N/A N/A N/A N/A N/A
5 AM Fri 38 38 S 5 N/A N/A N/A N/A N/A
6 AM Fri 39 39 S 5 N/A N/A N/A N/A N/A
7 AM Fri 40 40 S 7 N/A N/A N/A N/A N/A
8 AM Fri 41 41 S 7 N/A N/A N/A N/A N/A
9 AM Fri 43 43 S 7 N/A N/A N/A N/A N/A
10 AM Fri 44 44 S 8 N/A N/A N/A N/A N/A
11 AM Fri 45 45 S 8 N/A N/A N/A N/A N/A
12 Noon Fri 46 46 S 8 N/A N/A N/A N/A N/A
1 PM Fri 46 46 S 9 N/A N/A N/A N/A N/A
2 PM Fri 45 45 S 9 N/A N/A N/A N/A N/A
3 PM Fri 44 44 S 9 N/A N/A N/A N/A N/A
4 PM Fri 44 44 S 9 N/A N/A N/A N/A N/A
5 PM Fri 45 45 S 9 N/A N/A N/A N/A N/A
6 PM Fri 46 46 S 9 N/A N/A N/A N/A N/A
7 PM Fri 47 47 S 9 N/A N/A N/A N/A N/A
8 PM Fri 46 46 S 9 N/A N/A N/A N/A N/A
9 PM Fri 44 44 S 9 N/A N/A N/A N/A N/A
10 PM Fri 43 43 S 8 N/A N/A N/A N/A N/A
11 PM Fri 43 43 S 8 N/A N/A N/A N/A N/A
12 Midnight Sat 44 44 S 8 N/A N/A N/A N/A N/A
1 AM Sat 44 44 S 8 N/A N/A N/A N/A N/A
2 AM Sat 44 44 S 8 N/A N/A N/A N/A N/A
3 AM Sat 44 44 S 8 N/A N/A N/A N/A N/A
4 AM Sat 44 44 S 7 N/A N/A N/A N/A N/A
5 AM Sat 45 45 S 7 N/A N/A N/A N/A N/A
6 AM Sat 46 46 S 7 N/A N/A N/A N/A N/A
7 AM Sat 47 47 S 7 N/A N/A N/A N/A N/A
8 AM Sat 48 48 S 7 N/A N/A N/A N/A N/A
9 AM Sat 48 48 S 7 N/A N/A N/A N/A N/A
10 AM Sat 48 48 SW 7 N/A N/A N/A N/A N/A
11 AM Sat 50 50 SW 7 N/A N/A N/A N/A N/A
12 Noon Sat 51 51 SW 7 N/A N/A N/A N/A N/A
1 PM Sat 53 53 SW 7 N/A N/A N/A N/A N/A
2 PM Sat 54 54 SW 7 N/A N/A N/A N/A N/A
3 PM Sat 54 54 SW 7 N/A N/A N/A N/A N/A
4 PM Sat 54 54 SW 6 N/A N/A N/A N/A N/A
5 PM Sat 53 53 SW 6 N/A N/A N/A N/A N/A
6 PM Sat 52 52 SW 6 N/A N/A N/A N/A N/A
7 PM Sat 51 51 SW 6 N/A N/A N/A N/A N/A
8 PM Sat 50 50 SW 6 N/A N/A N/A N/A N/A
9 PM Sat 49 49 SW 6 N/A N/A N/A N/A N/A
10 PM Sat 49 49 SW 9 N/A N/A N/A N/A N/A
11 PM Sat 49 49 SW 9 N/A N/A N/A N/A N/A
12 Midnight Sun 49 49 SW 9 N/A N/A N/A N/A N/A
1 AM Sun 49 49 SW 9 N/A N/A N/A N/A N/A
2 AM Sun 49 49 SW 9 N/A N/A N/A N/A N/A
3 AM Sun 48 48 SW 9 N/A N/A N/A N/A N/A
4 AM Sun 48 48 SW 13 N/A N/A N/A N/A N/A
5 AM Sun 47 47 SW 13 N/A N/A N/A N/A N/A
6 AM Sun 46 46 SW 13 N/A N/A N/A N/A N/A
7 AM Sun 46 46 SW 13 N/A N/A N/A N/A N/A
8 AM Sun 46 46 SW 13 N/A N/A N/A N/A N/A
9 AM Sun 47 47 SW 13 N/A N/A N/A N/A N/A
10 AM Sun 47 47 SW 14 N/A N/A N/A N/A N/A
11 AM Sun 48 48 SW 14 N/A N/A N/A N/A N/A
12 Noon Sun 49 49 SW 14 N/A N/A N/A N/A N/A
1 PM Sun 49 49 SW 14 N/A N/A N/A N/A N/A
2 PM Sun 48 48 SW 14 N/A N/A N/A N/A N/A
3 PM Sun 47 47 SW 14 N/A N/A N/A N/A N/A
4 PM Sun 45 45 W 16 N/A N/A N/A N/A N/A
5 PM Sun 44 44 W 16 N/A N/A N/A N/A N/A
6 PM Sun 42 42 W 16 N/A N/A N/A N/A N/A
7 PM Sun 41 41 W 16 N/A N/A N/A N/A N/A
8 PM Sun 40 40 W 16 N/A N/A N/A N/A N/A
9 PM Sun 39 39 W 16 N/A N/A N/A N/A N/A
10 PM Sun 38 38 NW 12 N/A N/A N/A N/A N/A
11 PM Sun 38 38 NW 12 N/A N/A N/A N/A N/A
12 Midnight Mon 38 38 NW 12 N/A N/A N/A N/A N/A
1 AM Mon 37 37 NW 12 N/A N/A N/A N/A N/A
2 AM Mon 37 37 NW 12 N/A N/A N/A N/A N/A
3 AM Mon 37 37 NW 12 N/A N/A N/A N/A N/A
4 AM Mon 37 37 N 8 N/A N/A N/A N/A N/A
5 AM Mon 36 36 N 8 N/A N/A N/A N/A N/A
6 AM Mon 36 36 N 8 N/A N/A N/A N/A N/A
7 AM Mon 37 37 N 8 N/A N/A N/A N/A N/A
8 AM Mon 38 38 N 8 N/A N/A N/A N/A N/A
9 AM Mon 41 41 N 8 N/A N/A N/A N/A N/A
10 AM Mon 43 43 NE 7 N/A N/A N/A N/A N/A
11 AM Mon 46 47 NE 7 N/A N/A N/A N/A N/A
12 Noon Mon 48 49 NE 7 N/A N/A N/A N/A N/A
1 PM Mon 50 51 NE 7 N/A N/A N/A N/A N/A
2 PM Mon 51 52 NE 7 N/A N/A N/A N/A N/A
3 PM Mon 51 51 NE 7 N/A N/A N/A N/A N/A
4 PM Mon 50 50 N 7 N/A N/A N/A N/A N/A
5 PM Mon 48 48 N 7 N/A N/A N/A N/A N/A
6 PM Mon 45 45 N 7 N/A N/A N/A N/A N/A
7 PM Mon 43 43 N 7 N/A N/A N/A N/A N/A
8 PM Mon 42 42 N 7 N/A N/A N/A N/A N/A
9 PM Mon 41 41 N 7 N/A N/A N/A N/A N/A
10 PM Mon 41 41 N 8 N/A N/A N/A N/A N/A
11 PM Mon 41 41 N 8 N/A N/A N/A N/A N/A
12 Midnight Tue 40 40 N 8 N/A N/A N/A N/A N/A
1 AM Tue 39 39 N 8 N/A N/A N/A N/A N/A
2 AM Tue 39 39 N 8 N/A N/A N/A N/A N/A
3 AM Tue 38 38 N 8 N/A N/A N/A N/A N/A
4 AM Tue 38 38 N 9 N/A N/A N/A N/A N/A
5 AM Tue 38 38 N 9 N/A N/A N/A N/A N/A
6 AM Tue 38 38 N 9 N/A N/A N/A N/A N/A
7 AM Tue 39 39 N 9 N/A N/A N/A N/A N/A
8 AM Tue 41 41 N 9 N/A N/A N/A N/A N/A
9 AM Tue 43 43 N 9 N/A N/A N/A N/A N/A
10 AM Tue 47 47 NE 8 N/A N/A N/A N/A N/A
11 AM Tue 50 51 NE 8 N/A N/A N/A N/A N/A
12 Noon Tue 53 54 NE 8 N/A N/A N/A N/A N/A
1 PM Tue 56 57 NE 8 N/A N/A N/A N/A N/A
2 PM Tue 58 59 NE 8 N/A N/A N/A N/A N/A
3 PM Tue 58 58 NE 8 N/A N/A N/A N/A N/A
4 PM Tue 57 57 N 6 N/A N/A N/A N/A N/A
5 PM Tue 53 53 N 6 N/A N/A N/A N/A N/A
6 PM Tue 49 49 N 6 N/A N/A N/A N/A N/A
7 PM Tue 46 46 N 6 N/A N/A N/A N/A N/A
8 PM Tue 44 44 N 6 N/A N/A N/A N/A N/A
9 PM Tue 44 44 N 6 N/A N/A N/A N/A N/A
10 PM Tue 44 44 N 5 N/A N/A N/A N/A N/A
11 PM Tue 44 44 N 5 N/A N/A N/A N/A N/A
12 Midnight Wed 43 43 N 5 N/A N/A N/A N/A N/A
1 AM Wed 43 43 N 5 N/A N/A N/A N/A N/A
2 AM Wed 42 42 N 5 N/A N/A N/A N/A N/A
3 AM Wed 42 42 N 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 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