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

Station:

KOAK

Date/Time:

20 OCT 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 Sun 50 50 N 6 2441 4000 0 Blue 0
6 AM Sun 50 50 N 6 2441 4000 0 Blue 0
7 AM Sun 53 53 N 6 2441 4000 0 Blue 0
8 AM Sun 53 53 NW 6 2441 4000 0 Blue 0
9 AM Sun 58 58 NW 6 3006 4000 0 Blue 1
10 AM Sun 62 63 NW 6 5318 4297 297 Blue 6
11 AM Sun 63 65 NW 7 5947 4981 981 Blue 8
12 Noon Sun 65 67 NW 7 6552 5612 1612 Blue 10
1 PM Sun 65 68 NW 7 6949 5915 1915 Blue 11
2 PM Sun 67 69 NW 9 7229 6216 2216 Blue 12
3 PM Sun 67 69 NW 9 7229 6216 2216 Blue 12
4 PM Sun 67 68 NW 9 6949 5915 1915 Blue 11
5 PM Sun 67 67 NW 9 6552 5612 1612 Blue 10
6 PM Sun 62 62 NW 9 4996 4000 0 Blue 5
7 PM Sun 56 56 NW 9 2441 4000 0 Blue 0
8 PM Sun 55 55 N 7 2441 4000 0 Blue 0
9 PM Sun 56 56 N 7 2441 4000 0 Blue 0
10 PM Sun 56 56 N 7 2441 4000 0 Blue 0
11 PM Sun 56 56 N 6 2441 4000 0 Blue 0
12 Midnight Mon 56 56 N 6 2441 4000 0 Blue 0
1 AM Mon 56 56 N 6 2441 4000 0 Blue 0
2 AM Mon 56 56 N 6 2441 4000 0 Blue 0
3 AM Mon 57 57 N 6 2698 4000 0 Blue 0
4 AM Mon 56 56 N 6 2441 4000 0 Blue 0
5 AM Mon 57 57 N 6 2698 4000 0 Blue 0
6 AM Mon 55 55 N 6 2441 4000 0 Blue 0
7 AM Mon 55 55 N 6 2441 4000 0 Blue 0
8 AM Mon 56 56 N 5 2441 4000 0 Blue 0
9 AM Mon 62 62 N 5 4996 4000 0 Blue 5
10 AM Mon 69 70 N 5 7394 6514 2514 Blue 13
11 AM Mon 73 75 N 3 8289 7697 3697 Blue 18
12 Noon Mon 75 78 N 3 9401 8219 4219 Blue 21
1 PM Mon 77 80 N 3 10120 8958 4958 Blue 23
2 PM Mon 80 83 NW 5 10898 10033 6033 Blue 26
3 PM Mon 81 83 NW 5 10898 10033 6033 Blue 26
4 PM Mon 81 82 NW 5 10699 9679 5679 Blue 25
5 PM Mon 78 78 N 6 9401 8219 4219 Blue 21
6 PM Mon 73 73 N 6 7889 7369 3369 Blue 16
7 PM Mon 66 66 N 6 6251 5290 1290 Blue 9
8 PM Mon 61 61 N 6 4699 4000 0 Blue 4
9 PM Mon 60 60 N 6 4314 4000 0 Blue 3
10 PM Mon 61 61 N 6 4699 4000 0 Blue 4
11 PM Mon 62 62 E 5 4996 4000 0 Blue 5
12 Midnight Tue 63 63 E 5 5318 4297 297 Blue 6
1 AM Tue 62 62 E 5 4996 4000 0 Blue 5
2 AM Tue 61 61 E 5 4699 4000 0 Blue 4
3 AM Tue 61 61 E 5 4699 4000 0 Blue 4
4 AM Tue 62 62 E 5 4996 4000 0 Blue 5
5 AM Tue 61 61 N 6 4699 4000 0 Blue 4
6 AM Tue 60 60 N 6 4314 4000 0 Blue 3
7 AM Tue 59 59 N 6 3312 4000 0 Blue 2
8 AM Tue 60 60 N 6 4314 4000 0 Blue 3
9 AM Tue 65 65 N 6 5947 4981 981 Blue 8
10 AM Tue 71 72 N 6 7724 7204 3204 Blue 15
11 AM Tue 76 78 N 5 9401 8219 4219 Blue 21
12 Noon Tue 80 83 N 5 10898 10033 6033 Blue 26
1 PM Tue 81 84 N 5 11148 10448 6448 Blue 27
2 PM Tue 82 85 N 5 11396 10646 6646 Blue 28
3 PM Tue 83 85 N 5 11396 10646 6646 Blue 28
4 PM Tue 83 84 N 5 11148 10448 6448 Blue 27
5 PM Tue 80 80 NW 7 10120 8958 4958 Blue 23
6 PM Tue 75 75 NW 7 8289 7697 3697 Blue 18
7 PM Tue 68 68 NW 7 6949 5915 1915 Blue 11
8 PM Tue 63 63 NW 7 5318 4297 297 Blue 6
9 PM Tue 62 62 NW 7 4996 4000 0 Blue 5
10 PM Tue 63 63 NW 7 5318 4297 297 Blue 6
11 PM Tue 65 65 N 6 5947 4981 981 Blue 8
12 Midnight Wed 64 64 N 6 5642 4677 677 Blue 7
1 AM Wed 63 63 N 6 5318 4297 297 Blue 6
2 AM Wed 62 62 N 6 4996 4000 0 Blue 5
3 AM Wed 62 62 N 6 4996 4000 0 Blue 5
4 AM Wed 62 62 N 6 4996 4000 0 Blue 5
5 AM Wed 61 61 NE 8 4699 4000 0 Blue 4
6 AM Wed 60 60 NE 8 4314 4000 0 Blue 3
7 AM Wed 59 59 NE 8 3312 4000 0 Blue 2
8 AM Wed 60 60 NE 8 4314 4000 0 Blue 3
9 AM Wed 65 65 NE 8 5947 4981 981 Blue 8
10 AM Wed 71 72 NE 8 7724 7204 3204 Blue 15
11 AM Wed 77 79 N 12 9763 8591 4591 Blue 22
12 Noon Wed 80 83 N 12 10898 10033 6033 Blue 26
1 PM Wed 82 85 N 12 11396 10646 6646 Blue 28
2 PM Wed 82 85 N 12 11396 10646 6646 Blue 28
3 PM Wed 83 85 N 12 11396 10646 6646 Blue 28
4 PM Wed 83 84 N 12 11148 10448 6448 Blue 27
5 PM Wed 80 80 NW 12 10120 8958 4958 Blue 23
6 PM Wed 74 74 NW 12 8053 7533 3533 Blue 17
7 PM Wed 68 68 NW 12 6949 5915 1915 Blue 11
8 PM Wed 63 63 NW 12 5318 4297 297 Blue 6
9 PM Wed 61 61 NW 12 4699 4000 0 Blue 4
10 PM Wed 63 63 NW 12 5318 4297 297 Blue 6
11 PM Wed 64 64 NE 12 5642 4677 677 Blue 7
12 Midnight Thu 64 64 NE 12 5642 4677 677 Blue 7
1 AM Thu 63 63 NE 12 5318 4297 297 Blue 6
2 AM Thu 61 61 NE 12 4699 4000 0 Blue 4
3 AM Thu 61 61 NE 12 4699 4000 0 Blue 4
4 AM Thu 61 61 NE 12 4699 4000 0 Blue 4
5 AM Thu 60 60 NE 10 4314 4000 0 Blue 3
6 AM Thu 58 58 NE 10 3006 4000 0 Blue 1
7 AM Thu 57 57 NE 10 2698 4000 0 Blue 0
8 AM Thu 58 58 NE 10 3006 4000 0 Blue 1
9 AM Thu 61 61 NE 10 4699 4000 0 Blue 4
10 AM Thu 67 68 NE 10 6949 5915 1915 Blue 11
11 AM Thu 72 74 NE 10 8053 7533 3533 Blue 17
12 Noon Thu 75 78 NE 10 9401 8219 4219 Blue 21
1 PM Thu 78 81 NE 10 10499 9321 5321 Blue 24
2 PM Thu 79 82 NE 10 10699 9679 5679 Blue 25
3 PM Thu 81 83 NE 10 10898 10033 6033 Blue 26
4 PM Thu 81 82 NE 10 10699 9679 5679 Blue 25
5 PM Thu 78 78 NE 7 9401 8219 4219 Blue 21
6 PM Thu 73 73 NE 7 7889 7369 3369 Blue 16
7 PM Thu 65 65 NE 7 5947 4981 981 Blue 8
8 PM Thu 60 60 NE 7 4314 4000 0 Blue 3
9 PM Thu 59 59 NE 7 3312 4000 0 Blue 2
10 PM Thu 60 60 NE 7 4314 4000 0 Blue 3
11 PM Thu 61 61 NE 6 4699 4000 0 Blue 4
12 Midnight Fri 61 61 NE 6 4699 4000 0 Blue 4
1 AM Fri 60 60 NE 6 4314 4000 0 Blue 3
2 AM Fri 59 59 NE 6 3312 4000 0 Blue 2
3 AM Fri 59 59 NE 6 3312 4000 0 Blue 2
4 AM Fri 59 59 NE 6 3312 4000 0 Blue 2
5 AM Fri 59 59 NE 5 3312 4000 0 Blue 2
6 AM Fri 58 58 NE 5 3006 4000 0 Blue 1
7 AM Fri 57 57 NE 5 2698 4000 0 Blue 0
8 AM Fri 58 58 NE 5 3006 4000 0 Blue 1
9 AM Fri 62 62 NE 5 4996 4000 0 Blue 5
10 AM Fri 68 69 NE 5 7229 6216 2216 Blue 12
11 AM Fri 73 75 SE 2 8289 7697 3697 Blue 18
12 Noon Fri 76 79 SE 2 9763 8591 4591 Blue 22
1 PM Fri 78 82 SE 2 10699 9679 5679 Blue 25
2 PM Fri 78 81 SE 2 10499 9321 5321 Blue 24
3 PM Fri 79 81 SE 2 10499 9321 5321 Blue 24
4 PM Fri 79 80 SE 2 10120 8958 4958 Blue 23
5 PM Fri 76 76 W 7 8665 7861 3861 Blue 19
6 PM Fri 71 71 W 7 7559 6879 2879 Blue 14
7 PM Fri 65 65 W 7 5947 4981 981 Blue 8
8 PM Fri 60 60 W 7 4314 4000 0 Blue 3
9 PM Fri 58 58 W 7 3006 4000 0 Blue 1
10 PM Fri 59 59 W 7 3312 4000 0 Blue 2
11 PM Fri 59 59 N 5 3312 4000 0 Blue 2
12 Midnight Sat 59 59 N 5 3312 4000 0 Blue 2
1 AM Sat 59 59 N 5 3312 4000 0 Blue 2
2 AM Sat 58 58 N 5 3006 4000 0 Blue 1
3 AM Sat 58 58 N 5 3006 4000 0 Blue 1
4 AM Sat 58 58 N 5 3006 4000 0 Blue 1

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 [email protected]