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

Station:

KOAK

Date/Time:

28 MAR 2024

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 Thu 39 39 W 10 14 2612 4000 0 Blue 0
1 AM Thu 39 39 W 10 14 2612 4000 0 Blue 0
2 AM Thu 39 39 W 10 14 2612 4000 0 Blue 0
3 AM Thu 38 38 W 10 14 2612 4000 0 Blue 0
4 AM Thu 38 38 W 10 14 2612 4000 0 Blue 0
5 AM Thu 37 37 W 10 13 2612 4000 0 Blue 0
6 AM Thu 37 37 W 10 13 2612 4000 0 Blue 0
7 AM Thu 37 37 W 10 13 2612 4000 0 Blue 0
8 AM Thu 37 37 WSW 8 11 2612 4000 0 Blue 0
9 AM Thu 38 38 WSW 8 11 2612 4000 0 Blue 0
10 AM Thu 40 40 WSW 8 11 2612 4000 0 Blue 0
11 AM Thu 41 42 WSW 11 16 3131 4000 0 White 1
12 Noon Thu 42 43 WSW 11 16 3352 4000 0 White 2
1 PM Thu 43 44 WSW 11 16 3572 4000 0 White 3
2 PM Thu 44 45 W 11 16 3793 4000 0 White 4
3 PM Thu 44 45 W 11 16 3793 4000 0 White 4
4 PM Thu 45 45 W 11 16 3793 4000 0 White 4
5 PM Thu 44 44 W 10 13 3572 4000 0 White 3
6 PM Thu 42 42 W 10 13 3131 4000 0 White 1
7 PM Thu 41 41 W 10 13 2612 4000 0 Blue 0
8 PM Thu 38 38 W 6 10 2612 4000 0 Blue 0
9 PM Thu 38 38 W 6 10 2612 4000 0 Blue 0
10 PM Thu 37 37 W 6 10 2612 4000 0 Blue 0
11 PM Thu 37 37 SW 3 4 2612 4000 0 Blue 0
12 Midnight Fri 37 37 SW 3 4 2612 4000 0 Blue 0
1 AM Fri 37 37 SW 3 4 2612 4000 0 Blue 0
2 AM Fri 37 37 SSE 3 5 2612 4000 0 Blue 0
3 AM Fri 37 37 SSE 3 5 2612 4000 0 Blue 0
4 AM Fri 37 37 SSE 3 5 2612 4000 0 Blue 0
5 AM Fri 37 37 SE 6 10 2612 4000 0 Blue 0
6 AM Fri 37 37 SE 6 10 2612 4000 0 Blue 0
7 AM Fri 37 37 SE 6 10 2612 4000 0 Blue 0
8 AM Fri 37 37 SE 11 17 2612 4000 0 Blue 0
9 AM Fri 37 37 SE 11 17 2612 4000 0 Blue 0
10 AM Fri 39 39 SE 11 17 2612 4000 0 Blue 0
11 AM Fri 41 41 SE 16 24 2612 4000 0 Blue 0
12 Noon Fri 41 41 SE 16 24 2612 4000 0 Blue 0
1 PM Fri 41 41 SE 16 24 2612 4000 0 Blue 0
2 PM Fri 41 41 ESE 16 23 2612 4000 0 Blue 0
3 PM Fri 41 41 ESE 16 23 2612 4000 0 Blue 0
4 PM Fri 42 42 ESE 16 23 3131 4000 0 White 1
5 PM Fri 42 42 E 14 21 3131 4000 0 White 1
6 PM Fri 41 41 E 14 21 2612 4000 0 Blue 0
7 PM Fri 40 40 E 14 21 2612 4000 0 Blue 0
8 PM Fri 39 39 E 14 21 2612 4000 0 Blue 0
9 PM Fri 39 39 E 14 21 2612 4000 0 Blue 0
10 PM Fri 39 39 E 14 21 2612 4000 0 Blue 0
11 PM Fri 39 39 ENE 17 25 2612 4000 0 Blue 0
12 Midnight Sat 39 39 ENE 17 25 2612 4000 0 Blue 0
1 AM Sat 39 39 ENE 17 25 2612 4000 0 Blue 0
2 AM Sat 39 39 ENE 14 20 2612 4000 0 Blue 0
3 AM Sat 39 39 ENE 14 20 2612 4000 0 Blue 0
4 AM Sat 38 38 ENE 14 20 2612 4000 0 Blue 0
5 AM Sat 38 38 ENE 12 18 2612 4000 0 Blue 0
6 AM Sat 38 38 ENE 12 18 2612 4000 0 Blue 0
7 AM Sat 38 38 ENE 12 18 2612 4000 0 Blue 0
8 AM Sat 39 39 NE 10 14 2612 4000 0 Blue 0
9 AM Sat 41 41 NE 10 14 2612 4000 0 Blue 0
10 AM Sat 43 43 NE 10 14 3352 4000 0 White 2
11 AM Sat 45 46 ENE 10 14 4010 4010 10 White 5
12 Noon Sat 47 49 ENE 10 14 4661 4661 661 White 8
1 PM Sat 48 50 ENE 10 14 4891 4891 891 White 9
2 PM Sat 49 51 ENE 9 13 5104 5104 1104 White 10
3 PM Sat 50 51 ENE 9 13 5104 5104 1104 White 10
4 PM Sat 50 51 ENE 9 13 5104 5104 1104 White 10
5 PM Sat 50 50 NNE 10 14 4891 4891 891 White 9
6 PM Sat 48 48 NNE 10 14 4445 4445 445 White 7
7 PM Sat 46 46 NNE 10 14 4010 4010 10 White 5
8 PM Sat 44 44 NNW 8 11 3572 4000 0 White 3
9 PM Sat 43 43 NNW 8 11 3352 4000 0 White 2
10 PM Sat 42 42 NNW 8 11 3131 4000 0 White 1
11 PM Sat 41 41 N 8 11 2612 4000 0 Blue 0
12 Midnight Sun 40 40 N 8 11 2612 4000 0 Blue 0
1 AM Sun 40 40 N 8 11 2612 4000 0 Blue 0
2 AM Sun 39 39 N 6 9 2612 4000 0 Blue 0
3 AM Sun 38 38 N 6 9 2612 4000 0 Blue 0
4 AM Sun 38 38 N 6 9 2612 4000 0 Blue 0
5 AM Sun 38 38 NNE 6 9 2612 4000 0 Blue 0
6 AM Sun 38 38 NNE 6 9 2612 4000 0 Blue 0
7 AM Sun 38 38 NNE 6 9 2612 4000 0 Blue 0
8 AM Sun 40 40 NNE 6 9 2612 4000 0 Blue 0
9 AM Sun 43 44 NNE 6 9 3572 4000 0 White 3
10 AM Sun 47 49 NNE 6 9 4661 4661 661 White 8
11 AM Sun 51 54 W 9 12 5748 5748 1748 White 12
12 Noon Sun 53 57 W 9 12 6385 6385 2385 White 15
1 PM Sun 54 58 W 9 12 6598 6598 2598 White 16
2 PM Sun 55 59 W 11 16 6810 6810 2810 White 17
3 PM Sun 56 60 W 11 16 7020 7020 3020 White 18
4 PM Sun 56 58 W 11 16 6598 6598 2598 White 16
5 PM Sun 55 56 NW 9 17 6173 6173 2173 White 14
6 PM Sun 52 52 NW 9 17 5320 5320 1320 White 10
7 PM Sun 48 48 NW 9 17 4445 4445 445 White 7
8 PM Sun 45 45 NW 9 17 3793 4000 0 White 4
9 PM Sun 44 44 NW 9 17 3572 4000 0 White 3
10 PM Sun 43 43 NW 9 17 3352 4000 0 White 2
11 PM Sun 43 43 NNE 9 12 3352 4000 0 White 2
12 Midnight Mon 42 42 NNE 9 12 3131 4000 0 White 1
1 AM Mon 42 42 NNE 9 12 3131 4000 0 White 1
2 AM Mon 41 41 NNE 9 12 2612 4000 0 Blue 0
3 AM Mon 41 41 NNE 9 12 2612 4000 0 Blue 0
4 AM Mon 41 41 NNE 9 12 2612 4000 0 Blue 0
5 AM Mon 41 41 NNE 8 11 2612 4000 0 Blue 0
6 AM Mon 41 41 NNE 8 11 2612 4000 0 Blue 0
7 AM Mon 41 41 NNE 8 11 2612 4000 0 Blue 0
8 AM Mon 43 43 NNE 8 11 3352 4000 0 White 2
9 AM Mon 48 49 NNE 8 11 4661 4661 661 White 8
10 AM Mon 54 56 NNE 8 11 6173 6173 2173 White 14
11 AM Mon 59 63 NNW 9 13 7644 7644 3644 White 21
12 Noon Mon 62 67 NNW 9 13 8474 8474 4474 White 25
1 PM Mon 64 70 NNW 9 13 9090 9090 5090 White 28
2 PM Mon 65 71 NNW 9 13 9297 9297 5297 White 29
3 PM Mon 66 70 NNW 9 13 9090 9090 5090 White 28
4 PM Mon 67 70 NNW 9 13 9090 9090 5090 White 28
5 PM Mon 66 67 WNW 8 13 8474 8474 4474 White 25
6 PM Mon 63 63 WNW 8 13 7644 7644 3644 White 21
7 PM Mon 60 60 WNW 8 13 7020 7020 3020 White 18
8 PM Mon 56 56 WNW 8 13 6173 6173 2173 White 14
9 PM Mon 53 53 WNW 8 13 5534 5534 1534 White 11
10 PM Mon 51 51 WNW 8 13 5104 5104 1104 White 10
11 PM Mon 50 50 NNE 5 9 4891 4891 891 White 9
12 Midnight Tue 49 49 NNE 5 9 4661 4661 661 White 8
1 AM Tue 48 48 NNE 5 9 4445 4445 445 White 7
2 AM Tue 48 48 NNE 5 9 4445 4445 445 White 7
3 AM Tue 48 48 NNE 5 9 4445 4445 445 White 7
4 AM Tue 48 48 NNE 5 9 4445 4445 445 White 7
5 AM Tue 48 48 NE 5 8 4445 4445 445 White 7
6 AM Tue 48 48 NE 5 8 4445 4445 445 White 7
7 AM Tue 49 49 NE 5 8 4661 4661 661 White 8
8 AM Tue 51 51 NE 5 8 5104 5104 1104 White 10
9 AM Tue 55 56 NE 5 8 6173 6173 2173 White 14
10 AM Tue 60 62 NE 5 8 7435 7435 3435 White 20
11 AM Tue 64 68 SW 8 12 8680 8680 4680 White 26
12 Noon Tue 67 72 SW 8 12 9509 9509 5509 White 30
1 PM Tue 68 74 SW 8 12 9932 9932 5932 White 32
2 PM Tue 69 75 SW 8 12 10135 10135 6135 White 33
3 PM Tue 70 74 SW 8 12 9932 9932 5932 White 32
4 PM Tue 70 73 SW 8 12 9722 9722 5722 White 31
5 PM Tue 68 69 W 9 14 8885 8885 4885 White 27
6 PM Tue 64 64 W 9 14 7851 7851 3851 White 22
7 PM Tue 60 60 W 9 14 7020 7020 3020 White 18
8 PM Tue 56 56 W 9 14 6173 6173 2173 White 14
9 PM Tue 54 54 W 9 14 5748 5748 1748 White 12
10 PM Tue 53 53 W 9 14 5534 5534 1534 White 11

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]