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

Station:

KOAK

Date/Time:

14 APR 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 Sun 42 42 NNW 2 5 655 2000 0 Blue 0
1 AM Sun 43 43 NE 5 10 957 2000 0 Blue 0
2 AM Sun 43 43 ESE 9 13 957 2000 0 Blue 0
3 AM Sun 43 43 ESE 10 13 957 2000 0 Blue 0
4 AM Sun 42 42 ESE 10 16 655 2000 0 Blue 0
5 AM Sun 43 43 ESE 12 18 957 2000 0 Blue 0
6 AM Sun 43 43 ESE 12 19 957 2000 0 Blue 0
7 AM Sun 43 43 ESE 13 19 957 2000 0 Blue 0
8 AM Sun 44 44 ESE 12 19 1234 2000 0 Blue 0
9 AM Sun 46 46 SE 12 18 1743 2000 0 Blue 2
10 AM Sun 47 48 SE 13 21 2783 2000 0 Blue 4
11 AM Sun 49 50 SSE 12 18 3795 2189 189 White 6
12 Noon Sun 50 52 S 10 17 4225 3505 1505 White 8
1 PM Sun 51 53 S 10 14 4442 4219 2219 White 9
2 PM Sun 52 55 SSW 10 14 4878 4878 2878 White 11
3 PM Sun 53 55 SW 9 12 4878 4878 2878 White 11
4 PM Sun 54 55 SW 8 11 4878 4878 2878 White 11
5 PM Sun 53 53 WSW 6 10 4442 4219 2219 White 9
6 PM Sun 53 53 W 5 9 4442 4219 2219 White 9
7 PM Sun 53 53 WNW 4 6 4442 4219 2219 White 9
8 PM Sun 51 51 NNW 3 5 4010 2740 740 White 7
9 PM Sun 50 50 N 3 5 3795 2189 189 White 6
10 PM Sun 49 49 NNW 3 5 3580 2000 0 White 5
11 PM Sun 49 49 NNW 3 5 3580 2000 0 White 5
12 Midnight Mon 48 48 NNW 3 5 2783 2000 0 Blue 4
1 AM Mon 47 47 N 2 3 2205 2000 0 Blue 3
2 AM Mon 46 46 N 2 3 1743 2000 0 Blue 2
3 AM Mon 46 46 N 2 4 1743 2000 0 Blue 2
4 AM Mon 45 45 NNE 2 4 1303 2000 0 Blue 1
5 AM Mon 44 44 NNE 2 4 1234 2000 0 Blue 0
6 AM Mon 44 44 NNE 2 3 1234 2000 0 Blue 0
7 AM Mon 43 43 NNE 2 4 957 2000 0 Blue 0
8 AM Mon 46 46 NW 2 3 1743 2000 0 Blue 2
9 AM Mon 48 49 WNW 3 5 3580 2000 0 White 5
10 AM Mon 52 53 WNW 5 9 4442 4219 2219 White 9
11 AM Mon 55 57 W 6 10 5301 5301 3301 White 13
12 Noon Mon 56 59 W 6 10 5720 5720 3720 White 15
1 PM Mon 58 61 W 6 10 6139 6139 4139 White 17
2 PM Mon 60 65 W 9 12 6965 6965 4965 White 21
3 PM Mon 61 65 W 9 12 6965 6965 4965 White 21
4 PM Mon 62 64 W 9 12 6759 6759 4759 White 20
5 PM Mon 62 63 WNW 9 13 6553 6553 4553 White 19
6 PM Mon 61 61 WNW 9 13 6139 6139 4139 White 17
7 PM Mon 60 60 WNW 9 13 5930 5930 3930 White 16
8 PM Mon 58 58 NW 5 8 5511 5511 3511 White 14
9 PM Mon 56 56 NW 5 8 5089 5089 3089 White 12
10 PM Mon 55 55 NW 5 8 4878 4878 2878 White 11
11 PM Mon 53 53 NNE 3 5 4442 4219 2219 White 9
12 Midnight Tue 52 52 NNE 3 5 4225 3505 1505 White 8
1 AM Tue 51 51 NNE 3 5 4010 2740 740 White 7
2 AM Tue 50 50 NE 2 3 3795 2189 189 White 6
3 AM Tue 49 49 NE 2 3 3580 2000 0 White 5
4 AM Tue 48 48 NE 2 3 2783 2000 0 Blue 4
5 AM Tue 48 48 NE 2 4 2783 2000 0 Blue 4
6 AM Tue 49 49 NE 2 4 3580 2000 0 White 5
7 AM Tue 50 50 NE 2 4 3795 2189 189 White 6
8 AM Tue 52 52 E 2 3 4225 3505 1505 White 8
9 AM Tue 55 57 E 2 3 5301 5301 3301 White 13
10 AM Tue 59 63 E 2 3 6553 6553 4553 White 19
11 AM Tue 62 67 WSW 5 9 7375 7375 5375 White 23
12 Noon Tue 65 71 WSW 5 9 8189 8189 6189 White 27
1 PM Tue 67 73 WSW 5 9 8594 8594 6594 White 29
2 PM Tue 68 74 W 8 11 8795 8795 6795 White 30
3 PM Tue 69 74 W 8 11 8795 8795 6795 White 30
4 PM Tue 70 73 W 8 11 8594 8594 6594 White 29
5 PM Tue 70 71 WNW 8 11 8189 8189 6189 White 27
6 PM Tue 69 69 WNW 8 11 7785 7785 5785 White 25
7 PM Tue 67 67 WNW 8 11 7375 7375 5375 White 23
8 PM Tue 65 65 NNW 5 8 6965 6965 4965 White 21
9 PM Tue 63 63 NNW 5 8 6553 6553 4553 White 19
10 PM Tue 61 61 NNW 5 8 6139 6139 4139 White 17
11 PM Tue 59 59 NNE 4 6 5720 5720 3720 White 15
12 Midnight Wed 58 58 NNE 4 6 5511 5511 3511 White 14
1 AM Wed 57 57 NNE 4 6 5301 5301 3301 White 13
2 AM Wed 56 56 NE 4 6 5089 5089 3089 White 12
3 AM Wed 55 55 NE 4 6 4878 4878 2878 White 11
4 AM Wed 55 55 NE 4 6 4878 4878 2878 White 11
5 AM Wed 55 55 ENE 4 5 4878 4878 2878 White 11
6 AM Wed 55 55 ENE 4 5 4878 4878 2878 White 11
7 AM Wed 55 55 ENE 4 5 4878 4878 2878 White 11
8 AM Wed 57 57 ENE 3 8 5301 5301 3301 White 13
9 AM Wed 60 62 ENE 3 8 6346 6346 4346 White 18
10 AM Wed 64 67 ENE 3 8 7375 7375 5375 White 23
11 AM Wed 68 72 WSW 5 10 8394 8394 6394 White 28
12 Noon Wed 70 75 WSW 5 10 8995 8995 6995 White 31
1 PM Wed 72 77 WSW 5 10 9395 9395 7395 White 33
2 PM Wed 73 78 W 10 14 9591 9591 7591 White 34
3 PM Wed 74 78 W 10 14 9591 9591 7591 White 34
4 PM Wed 75 78 W 10 14 9591 9591 7591 White 34
5 PM Wed 75 76 WNW 11 16 9195 9195 7195 White 32
6 PM Wed 74 74 WNW 11 16 8795 8795 6795 White 30
7 PM Wed 71 71 WNW 11 16 8189 8189 6189 White 27
8 PM Wed 69 69 NNW 6 11 7785 7785 5785 White 25
9 PM Wed 67 67 NNW 6 11 7375 7375 5375 White 23
10 PM Wed 65 65 NNW 6 11 6965 6965 4965 White 21
11 PM Wed 63 63 NE 5 9 6553 6553 4553 White 19
12 Midnight Thu 62 62 NE 5 9 6346 6346 4346 White 18
1 AM Thu 61 61 NE 5 9 6139 6139 4139 White 17
2 AM Thu 60 60 ENE 5 9 5930 5930 3930 White 16
3 AM Thu 59 59 ENE 5 9 5720 5720 3720 White 15
4 AM Thu 58 58 ENE 5 9 5511 5511 3511 White 14
5 AM Thu 58 58 ENE 5 8 5511 5511 3511 White 14
6 AM Thu 58 58 ENE 5 8 5511 5511 3511 White 14
7 AM Thu 59 59 ENE 5 8 5720 5720 3720 White 15
8 AM Thu 61 61 ENE 5 8 6139 6139 4139 White 17
9 AM Thu 64 65 ENE 5 8 6965 6965 4965 White 21
10 AM Thu 68 70 ENE 5 8 7987 7987 5987 White 26
11 AM Thu 72 76 SW 6 9 9195 9195 7195 White 32
12 Noon Thu 74 78 SW 6 9 9591 9591 7591 White 34
1 PM Thu 75 80 SW 6 9 10009 10009 8009 White 36
2 PM Thu 76 81 W 9 12 10205 10205 8205 White 37
3 PM Thu 77 81 W 9 12 10205 10205 8205 White 37
4 PM Thu 77 79 W 9 12 9811 9811 7811 White 35
5 PM Thu 77 78 W 9 13 9591 9591 7591 White 34
6 PM Thu 76 76 W 9 13 9195 9195 7195 White 32
7 PM Thu 73 73 W 9 13 8594 8594 6594 White 29
8 PM Thu 71 71 NNW 5 9 8189 8189 6189 White 27
9 PM Thu 69 69 NNW 5 9 7785 7785 5785 White 25
10 PM Thu 66 66 NNW 5 9 7169 7169 5169 White 22
11 PM Thu 64 64 NE 5 8 6759 6759 4759 White 20
12 Midnight Fri 62 62 NE 5 8 6346 6346 4346 White 18
1 AM Fri 61 61 NE 5 8 6139 6139 4139 White 17
2 AM Fri 60 60 NE 5 8 5930 5930 3930 White 16
3 AM Fri 59 59 NE 5 8 5720 5720 3720 White 15
4 AM Fri 59 59 NE 5 8 5720 5720 3720 White 15
5 AM Fri 59 59 NE 5 9 5720 5720 3720 White 15
6 AM Fri 59 59 NE 5 9 5720 5720 3720 White 15
7 AM Fri 59 59 NE 5 9 5720 5720 3720 White 15
8 AM Fri 61 61 NE 5 9 6139 6139 4139 White 17
9 AM Fri 64 65 NE 5 9 6965 6965 4965 White 21
10 AM Fri 68 71 NE 5 9 8189 8189 6189 White 27
11 AM Fri 72 77 W 6 11 9395 9395 7395 White 33
12 Noon Fri 74 80 W 6 11 10009 10009 8009 White 36
1 PM Fri 75 81 W 6 11 10205 10205 8205 White 37
2 PM Fri 75 81 W 10 16 10205 10205 8205 White 37
3 PM Fri 76 81 W 10 16 10205 10205 8205 White 37
4 PM Fri 76 79 W 10 16 9811 9811 7811 White 35
5 PM Fri 75 76 WNW 10 16 9195 9195 7195 White 32
6 PM Fri 73 73 WNW 10 16 8594 8594 6594 White 29
7 PM Fri 71 71 WNW 10 16 8189 8189 6189 White 27
8 PM Fri 69 69 NW 8 12 7785 7785 5785 White 25
9 PM Fri 67 67 NW 8 12 7375 7375 5375 White 23
10 PM Fri 66 66 NW 8 12 7169 7169 5169 White 22

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]