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

Station:

KOAK

Date/Time:

22 MAR 2019

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)
5 AM Fri 40 40 S 6 2615 4000 0 Blue 0
6 AM Fri 40 40 S 6 2615 4000 0 Blue 0
7 AM Fri 41 41 S 6 2615 4000 0 Blue 0
8 AM Fri 42 42 SE 9 2615 4000 0 Blue 0
9 AM Fri 43 43 SE 9 2627 4000 0 Blue 0
10 AM Fri 44 44 SE 9 2785 4000 0 Blue 1
11 AM Fri 44 44 S 12 2785 4000 0 Blue 1
12 Noon Fri 45 45 S 12 2919 4000 0 Blue 2
1 PM Fri 46 46 S 12 3083 4000 0 Blue 3
2 PM Fri 47 47 S 9 3517 4000 0 Blue 4
3 PM Fri 47 47 S 9 3517 4000 0 Blue 4
4 PM Fri 47 47 S 9 3517 4000 0 Blue 4
5 PM Fri 47 47 S 8 3517 4000 0 Blue 4
6 PM Fri 47 47 S 8 3517 4000 0 Blue 4
7 PM Fri 47 47 S 8 3517 4000 0 Blue 4
8 PM Fri 47 47 S 5 3517 4000 0 Blue 4
9 PM Fri 47 47 S 5 3517 4000 0 Blue 4
10 PM Fri 47 47 S 5 3517 4000 0 Blue 4
11 PM Fri 47 47 SW 5 3517 4000 0 Blue 4
12 Midnight Sat 46 46 SW 5 3083 4000 0 Blue 3
1 AM Sat 45 45 SW 5 2919 4000 0 Blue 2
2 AM Sat 44 44 W 6 2785 4000 0 Blue 1
3 AM Sat 43 43 W 6 2627 4000 0 Blue 0
4 AM Sat 42 42 W 6 2615 4000 0 Blue 0
5 AM Sat 41 41 NW 7 2615 4000 0 Blue 0
6 AM Sat 39 39 NW 7 2615 4000 0 Blue 0
7 AM Sat 37 37 NW 7 2615 4000 0 Blue 0
8 AM Sat 37 37 NW 6 2615 4000 0 Blue 0
9 AM Sat 39 39 NW 6 2615 4000 0 Blue 0
10 AM Sat 42 43 NW 6 2627 4000 0 Blue 0
11 AM Sat 45 47 NW 7 3517 4000 0 Blue 4
12 Noon Sat 48 50 NW 7 4498 4000 0 Blue 7
1 PM Sat 50 53 NW 7 5082 4489 489 Blue 10
2 PM Sat 51 54 W 8 5408 4640 640 Blue 11
3 PM Sat 51 53 W 8 5082 4489 489 Blue 10
4 PM Sat 51 52 W 8 4803 4217 217 Blue 9
5 PM Sat 50 51 W 7 4650 4000 0 Blue 8
6 PM Sat 48 48 W 7 3858 4000 0 Blue 5
7 PM Sat 46 46 W 7 3083 4000 0 Blue 3
8 PM Sat 44 44 W 7 2785 4000 0 Blue 1
9 PM Sat 42 42 W 7 2615 4000 0 Blue 0
10 PM Sat 42 42 W 7 2615 4000 0 Blue 0
11 PM Sat 41 41 E 5 2615 4000 0 Blue 0
12 Midnight Sun 40 40 E 5 2615 4000 0 Blue 0
1 AM Sun 39 39 E 5 2615 4000 0 Blue 0
2 AM Sun 38 38 E 5 2615 4000 0 Blue 0
3 AM Sun 38 38 E 5 2615 4000 0 Blue 0
4 AM Sun 38 38 E 5 2615 4000 0 Blue 0
5 AM Sun 38 38 E 6 2615 4000 0 Blue 0
6 AM Sun 37 37 E 6 2615 4000 0 Blue 0
7 AM Sun 37 37 E 6 2615 4000 0 Blue 0
8 AM Sun 38 38 E 6 2615 4000 0 Blue 0
9 AM Sun 41 41 E 6 2615 4000 0 Blue 0
10 AM Sun 45 46 E 6 3083 4000 0 Blue 3
11 AM Sun 49 51 SE 8 4650 4000 0 Blue 8
12 Noon Sun 52 55 SE 8 5898 4792 792 Blue 12
1 PM Sun 54 57 SE 8 6843 5364 1364 Blue 14
2 PM Sun 55 58 SE 8 7067 5847 1847 Blue 15
3 PM Sun 55 57 SE 8 6843 5364 1364 Blue 14
4 PM Sun 54 55 SE 8 5898 4792 792 Blue 12
5 PM Sun 53 53 SE 12 5082 4489 489 Blue 10
6 PM Sun 50 50 SE 12 4498 4000 0 Blue 7
7 PM Sun 48 48 SE 12 3858 4000 0 Blue 5
8 PM Sun 46 46 SE 12 3083 4000 0 Blue 3
9 PM Sun 44 44 SE 12 2785 4000 0 Blue 1
10 PM Sun 43 43 SE 12 2627 4000 0 Blue 0
11 PM Sun 42 42 SE 12 2615 4000 0 Blue 0
12 Midnight Mon 42 42 SE 12 2615 4000 0 Blue 0
1 AM Mon 42 42 SE 12 2615 4000 0 Blue 0
2 AM Mon 41 41 SE 12 2615 4000 0 Blue 0
3 AM Mon 41 41 SE 12 2615 4000 0 Blue 0
4 AM Mon 41 41 SE 12 2615 4000 0 Blue 0
5 AM Mon 40 40 S 10 2615 4000 0 Blue 0
6 AM Mon 40 40 S 10 2615 4000 0 Blue 0
7 AM Mon 39 39 S 10 2615 4000 0 Blue 0
8 AM Mon 39 39 S 10 2615 4000 0 Blue 0
9 AM Mon 40 40 S 10 2615 4000 0 Blue 0
10 AM Mon 42 42 S 10 2615 4000 0 Blue 0
11 AM Mon 44 44 S 9 2785 4000 0 Blue 1
12 Noon Mon 46 46 S 9 3083 4000 0 Blue 3
1 PM Mon 48 48 S 9 3858 4000 0 Blue 5
2 PM Mon 49 49 S 9 4234 4000 0 Blue 6
3 PM Mon 50 50 S 9 4498 4000 0 Blue 7
4 PM Mon 50 50 S 9 4498 4000 0 Blue 7
5 PM Mon 49 49 S 8 4234 4000 0 Blue 6
6 PM Mon 48 48 S 8 3858 4000 0 Blue 5
7 PM Mon 46 46 S 8 3083 4000 0 Blue 3
8 PM Mon 45 45 S 8 2919 4000 0 Blue 2
9 PM Mon 43 43 S 8 2627 4000 0 Blue 0
10 PM Mon 43 43 S 8 2627 4000 0 Blue 0
11 PM Mon 42 42 S 3 2615 4000 0 Blue 0
12 Midnight Tue 41 41 S 3 2615 4000 0 Blue 0
1 AM Tue 40 40 S 3 2615 4000 0 Blue 0
2 AM Tue 40 40 S 3 2615 4000 0 Blue 0
3 AM Tue 39 39 S 3 2615 4000 0 Blue 0
4 AM Tue 39 39 S 3 2615 4000 0 Blue 0
5 AM Tue 39 39 SE 6 2615 4000 0 Blue 0
6 AM Tue 38 38 SE 6 2615 4000 0 Blue 0
7 AM Tue 38 38 SE 6 2615 4000 0 Blue 0
8 AM Tue 39 39 SE 6 2615 4000 0 Blue 0
9 AM Tue 40 40 SE 6 2615 4000 0 Blue 0
10 AM Tue 42 42 SE 6 2615 4000 0 Blue 0
11 AM Tue 45 45 SE 8 2919 4000 0 Blue 2
12 Noon Tue 47 47 SE 8 3517 4000 0 Blue 4
1 PM Tue 49 49 SE 8 4234 4000 0 Blue 6
2 PM Tue 50 50 SE 8 4498 4000 0 Blue 7
3 PM Tue 50 50 SE 8 4498 4000 0 Blue 7
4 PM Tue 49 49 SE 8 4234 4000 0 Blue 6
5 PM Tue 47 47 S 9 3517 4000 0 Blue 4
6 PM Tue 45 45 S 9 2919 4000 0 Blue 2
7 PM Tue 43 43 S 9 2627 4000 0 Blue 0
8 PM Tue 42 42 S 9 2615 4000 0 Blue 0
9 PM Tue 42 42 S 9 2615 4000 0 Blue 0
10 PM Tue 43 43 S 9 2627 4000 0 Blue 0
11 PM Tue 43 43 S 7 2627 4000 0 Blue 0
12 Midnight Wed 43 43 S 7 2627 4000 0 Blue 0
1 AM Wed 43 43 S 7 2627 4000 0 Blue 0
2 AM Wed 42 42 S 7 2615 4000 0 Blue 0
3 AM Wed 41 41 S 7 2615 4000 0 Blue 0
4 AM Wed 40 40 S 7 2615 4000 0 Blue 0
5 AM Wed 40 40 S 9 2615 4000 0 Blue 0
6 AM Wed 40 40 S 9 2615 4000 0 Blue 0
7 AM Wed 40 40 S 9 2615 4000 0 Blue 0
8 AM Wed 41 41 S 9 2615 4000 0 Blue 0
9 AM Wed 43 43 S 9 2627 4000 0 Blue 0
10 AM Wed 44 44 S 9 2785 4000 0 Blue 1
11 AM Wed 46 46 SW 10 3083 4000 0 Blue 3
12 Noon Wed 47 47 SW 10 3517 4000 0 Blue 4
1 PM Wed 47 47 SW 10 3517 4000 0 Blue 4
2 PM Wed 47 47 SW 10 3517 4000 0 Blue 4
3 PM Wed 47 47 SW 10 3517 4000 0 Blue 4
4 PM Wed 47 47 SW 10 3517 4000 0 Blue 4
5 PM Wed 46 46 SW 14 3083 4000 0 Blue 3
6 PM Wed 45 45 SW 14 2919 4000 0 Blue 2
7 PM Wed 44 44 SW 14 2785 4000 0 Blue 1
8 PM Wed 43 43 SW 14 2627 4000 0 Blue 0
9 PM Wed 42 42 SW 14 2615 4000 0 Blue 0
10 PM Wed 41 41 SW 14 2615 4000 0 Blue 0
11 PM Wed 40 40 W 9 2615 4000 0 Blue 0
12 Midnight Thu 39 39 W 9 2615 4000 0 Blue 0
1 AM Thu 39 39 W 9 2615 4000 0 Blue 0
2 AM Thu 39 39 W 9 2615 4000 0 Blue 0
3 AM Thu 39 39 W 9 2615 4000 0 Blue 0
4 AM Thu 39 39 W 9 2615 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