Detailed Predictions for: Lake McClure
Launch Lat, Long, Altitude (f): 37.712452, -120.2343, 2000
LZ Altitude (f): 500
Sounding

Station:

 KOAK

Date/Time UTC:

 260516/1200

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 Sat 67 67 NNW 3 6 2392 2065 65 Blue 12
1 AM Sat 65 65 N 2 4 2179 2000 0 Blue 10
2 AM Sat 63 63 NNW 1 4 1958 2000 0 Blue 8
3 AM Sat 61 61 N 1 3 1738 2000 0 Blue 6
4 AM Sat 61 61 NNW 1 4 1738 2000 0 Blue 6
5 AM Sat 59 59 NNW 1 4 1555 2000 0 Blue 4
6 AM Sat 59 59 NNW 2 5 1555 2000 0 Blue 4
7 AM Sat 61 61 NW 3 8 1738 2000 0 Blue 6
8 AM Sat 61 62 NW 4 10 1848 2000 0 Blue 7
9 AM Sat 63 66 NW 6 13 2289 2000 0 Blue 11
10 AM Sat 66 71 WNW 9 18 3997 2424 424 Blue 16
11 AM Sat 69 76 WNW 10 19 7305 4453 2453 Blue 21
12 Noon Sat 71 79 WNW 11 21 8853 7076 5076 Blue 24
1 PM Sat 74 82 WNW 12 24 10301 8684 6684 Blue 27
2 PM Sat 76 84 NW 12 24 10842 9860 7860 Blue 29
3 PM Sat 76 82 NW 12 25 10301 8684 6684 Blue 27
4 PM Sat 78 82 NW 12 25 10301 8684 6684 Blue 27
5 PM Sat 77 79 NW 12 25 8853 7076 5076 Blue 24
6 PM Sat 77 78 NW 13 26 8188 5811 3811 Blue 23
7 PM Sat 76 76 NW 12 26 7305 4453 2453 Blue 21
8 PM Sat 73 73 NW 11 24 4479 3135 1135 Blue 18
9 PM Sat 70 70 NNW 10 20 3198 2391 391 Blue 15
10 PM Sat 68 68 NNW 8 14 2425 2175 175 Blue 13
11 PM Sat 65 65 NW 6 12 2179 2000 0 Blue 10
12 Midnight Sun 63 63 NNW 4 9 1958 2000 0 Blue 8
1 AM Sun 62 62 NNW 2 6 1848 2000 0 Blue 7
2 AM Sun 60 60 NNW 2 4 1627 2000 0 Blue 5
3 AM Sun 58 58 NNW 1 4 1526 2000 0 Blue 3
4 AM Sun 57 57 NNW 1 3 1498 2000 0 Blue 2
5 AM Sun 56 56 NW 1 4 1447 2000 0 Blue 1
6 AM Sun 56 56 NW 1 4 1447 2000 0 Blue 1
7 AM Sun 58 58 NW 1 4 1526 2000 0 Blue 3
8 AM Sun 58 59 W 4 13 1555 2000 0 Blue 4
9 AM Sun 60 63 W 4 13 1958 2000 0 Blue 8
10 AM Sun 64 68 W 4 13 2425 2175 175 Blue 13
11 AM Sun 66 72 W 11 24 4239 2667 667 Blue 17
12 Noon Sun 70 78 W 11 24 8188 5811 3811 Blue 23
1 PM Sun 71 79 W 11 24 8853 7076 5076 Blue 24
2 PM Sun 73 81 WNW 12 25 9957 8095 6095 Blue 26
3 PM Sun 74 80 WNW 12 25 9523 7691 5691 Blue 25
4 PM Sun 74 78 WNW 12 25 8188 5811 3811 Blue 23
5 PM Sun 75 77 NW 13 26 7780 4691 2691 Blue 22
6 PM Sun 75 76 NW 13 26 7305 4453 2453 Blue 21
7 PM Sun 74 74 NW 13 26 4769 3975 1975 Blue 19
8 PM Sun 72 72 NNW 10 20 4239 2667 667 Blue 17
9 PM Sun 70 70 NNW 10 20 3198 2391 391 Blue 15
10 PM Sun 67 67 NNW 10 20 2392 2065 65 Blue 12
11 PM Sun 65 65 NE 11 20 2179 2000 0 Blue 10
12 Midnight Mon 63 63 NE 11 20 1958 2000 0 Blue 8
1 AM Mon 62 62 NE 11 20 1848 2000 0 Blue 7
2 AM Mon 60 60 NE 6 11 1627 2000 0 Blue 5
3 AM Mon 59 59 NE 6 11 1555 2000 0 Blue 4
4 AM Mon 58 58 NE 6 11 1526 2000 0 Blue 3
5 AM Mon 57 57 ENE 4 6 1498 2000 0 Blue 2
6 AM Mon 58 58 ENE 4 6 1526 2000 0 Blue 3
7 AM Mon 60 60 ENE 4 6 1627 2000 0 Blue 5
8 AM Mon 63 64 ENE 1 4 2069 2000 0 Blue 9
9 AM Mon 66 69 ENE 1 4 2688 2285 285 Blue 14
10 AM Mon 70 75 ENE 1 4 6031 4215 2215 Blue 20
11 AM Mon 73 80 WSW 5 11 9523 7691 5691 Blue 25
12 Noon Mon 75 83 WSW 5 11 10575 9340 7340 Blue 28
1 PM Mon 77 85 WSW 5 11 11106 10191 8191 Blue 30
2 PM Mon 78 86 W 6 12 11370 10491 8491 Blue 31
3 PM Mon 79 85 W 6 12 11106 10191 8191 Blue 30
4 PM Mon 80 84 W 6 12 10842 9860 7860 Blue 29
5 PM Mon 80 82 WNW 6 12 10301 8684 6684 Blue 27
6 PM Mon 79 80 WNW 6 12 9523 7691 5691 Blue 25
7 PM Mon 77 77 WNW 6 12 7780 4691 2691 Blue 22
8 PM Mon 75 75 NNW 3 5 6031 4215 2215 Blue 20
9 PM Mon 72 72 NNW 3 5 4239 2667 667 Blue 17
10 PM Mon 69 69 NNW 3 5 2688 2285 285 Blue 14
11 PM Mon 66 66 NE 4 5 2289 2000 0 Blue 11
12 Midnight Tue 64 64 NE 4 5 2069 2000 0 Blue 9
1 AM Tue 63 63 NE 4 5 1958 2000 0 Blue 8
2 AM Tue 62 62 ENE 3 5 1848 2000 0 Blue 7
3 AM Tue 60 60 ENE 3 5 1627 2000 0 Blue 5
4 AM Tue 60 60 ENE 3 5 1627 2000 0 Blue 5
5 AM Tue 60 60 ENE 4 6 1627 2000 0 Blue 5
6 AM Tue 62 62 ENE 4 6 1848 2000 0 Blue 7
7 AM Tue 64 64 ENE 4 6 2069 2000 0 Blue 9
8 AM Tue 67 68 ENE 1 4 2425 2175 175 Blue 13
9 AM Tue 71 74 ENE 1 4 4769 3975 1975 Blue 19
10 AM Tue 75 80 ENE 1 4 9523 7691 5691 Blue 25
11 AM Tue 78 85 WSW 5 10 11106 10191 8191 Blue 30
12 Noon Tue 80 88 WSW 5 10 11891 11018 9018 Blue 33
1 PM Tue 82 90 WSW 5 10 12331 11539 9539 Blue 35
2 PM Tue 84 92 W 6 12 12692 12053 10053 Blue 37
3 PM Tue 85 91 W 6 12 12512 11797 9797 Blue 36
4 PM Tue 86 90 W 6 12 12331 11539 9539 Blue 35
5 PM Tue 85 87 WNW 6 11 11631 10755 8755 Blue 32
6 PM Tue 83 84 WNW 6 11 10842 9860 7860 Blue 29
7 PM Tue 81 81 WNW 6 11 9957 8095 6095 Blue 26
8 PM Tue 79 79 N 3 6 8853 7076 5076 Blue 24
9 PM Tue 76 76 N 3 6 7305 4453 2453 Blue 21
10 PM Tue 73 73 N 3 6 4479 3135 1135 Blue 18
11 PM Tue 70 70 NE 4 6 3198 2391 391 Blue 15
12 Midnight Wed 68 68 NE 4 6 2425 2175 175 Blue 13
1 AM Wed 67 67 NE 4 6 2392 2065 65 Blue 12
2 AM Wed 66 66 NE 3 4 2289 2000 0 Blue 11
3 AM Wed 65 65 NE 3 4 2179 2000 0 Blue 10
4 AM Wed 64 64 NE 3 4 2069 2000 0 Blue 9
5 AM Wed 64 64 ENE 3 5 2069 2000 0 Blue 9
6 AM Wed 66 66 ENE 3 5 2289 2000 0 Blue 11
7 AM Wed 69 69 ENE 3 5 2688 2285 285 Blue 14
8 AM Wed 72 73 ENE 1 4 4479 3135 1135 Blue 18
9 AM Wed 75 78 ENE 1 4 8188 5811 3811 Blue 23
10 AM Wed 79 84 ENE 1 4 10842 9860 7860 Blue 29
11 AM Wed 82 87 SW 4 10 11631 10755 8755 Blue 32
12 Noon Wed 84 90 SW 4 10 12331 11539 9539 Blue 35
1 PM Wed 86 93 SW 4 10 12872 12262 10262 Blue 38
2 PM Wed 87 93 W 6 13 12872 12262 10262 Blue 38
3 PM Wed 88 93 W 6 13 12872 12262 10262 Blue 38
4 PM Wed 89 93 W 6 13 12872 12262 10262 Blue 38
5 PM Wed 89 91 WNW 6 12 12512 11797 9797 Blue 36
6 PM Wed 88 89 WNW 6 12 12149 11279 9279 Blue 34
7 PM Wed 86 86 WNW 6 12 11370 10491 8491 Blue 31
8 PM Wed 83 83 N 3 6 10575 9340 7340 Blue 28
9 PM Wed 80 80 N 3 6 9523 7691 5691 Blue 25
10 PM Wed 76 76 N 3 6 7305 4453 2453 Blue 21
11 PM Wed 73 73 NNE 4 5 4479 3135 1135 Blue 18
12 Midnight Thu 71 71 NNE 4 5 3997 2424 424 Blue 16
1 AM Thu 70 70 NNE 4 5 3198 2391 391 Blue 15
2 AM Thu 69 69 NE 2 4 2688 2285 285 Blue 14
3 AM Thu 68 68 NE 2 4 2425 2175 175 Blue 13
4 AM Thu 67 67 NE 2 4 2392 2065 65 Blue 12
5 AM Thu 67 67 ENE 3 4 2392 2065 65 Blue 12
6 AM Thu 68 68 ENE 3 4 2425 2175 175 Blue 13
7 AM Thu 69 69 ENE 3 4 2688 2285 285 Blue 14
8 AM Thu 72 73 ENE 1 4 4479 3135 1135 Blue 18
9 AM Thu 76 79 ENE 1 4 8853 7076 5076 Blue 24
10 AM Thu 81 86 ENE 1 4 11370 10491 8491 Blue 31
11 AM Thu 85 92 WSW 5 10 12692 12053 10053 Blue 37
12 Noon Thu 87 95 WSW 5 10 13436 12621 10621 White 40
1 PM Thu 89 97 WSW 5 10 13831 12974 10974 White 42
2 PM Thu 90 98 W 8 14 14026 13279 11279 White 43
3 PM Thu 91 97 W 8 14 13831 12974 10974 White 42
4 PM Thu 92 96 W 8 14 13633 12800 10800 White 41
5 PM Thu 92 94 WNW 8 14 13041 12442 10442 Blue 39
6 PM Thu 90 91 WNW 8 14 12512 11797 9797 Blue 36
7 PM Thu 88 88 WNW 8 14 11891 11018 9018 Blue 33
8 PM Thu 85 85 NNW 5 11 11106 10191 8191 Blue 30
9 PM Thu 82 82 NNW 5 11 10301 8684 6684 Blue 27
10 PM Thu 79 79 NNW 5 11 8853 7076 5076 Blue 24

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]