Detailed Predictions for: Potato Hill
Launch Lat, Long, Altitude (f): 39.34098, -122.69, 3400
LZ Altitude (f): 1700
Sounding

Station:

KOAK

Date/Time:

24 JUL 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 Wed 85 83 WSW 4 8 2710 3400 0 Blue 0
1 AM Wed 85 83 WSW 3 6 2710 3400 0 Blue 0
2 AM Wed 84 82 WSW 3 5 2710 3400 0 Blue 0
3 AM Wed 83 81 WSW 2 5 2710 3400 0 Blue 0
4 AM Wed 82 80 WSW 2 4 2710 3400 0 Blue 0
5 AM Wed 81 79 W 2 3 2710 3400 0 Blue 0
6 AM Wed 80 78 SW 1 2 2710 3400 0 Blue 0
7 AM Wed 80 78 SSW 1 2 2710 3400 0 Blue 0
8 AM Wed 81 80 S 1 2 2710 3400 0 Blue 0
9 AM Wed 84 84 SE 2 3 2710 3400 0 Blue 0
10 AM Wed 87 89 ESE 3 6 4112 3694 294 Blue 5
11 AM Wed 91 95 SE 5 11 6555 4838 1438 Blue 11
12 Noon Wed 94 99 SSE 8 14 11001 7070 3670 Blue 15
1 PM Wed 95 101 SSW 10 18 12174 10092 6692 Blue 17
2 PM Wed 97 103 SW 14 23 14464 11776 8376 Blue 19
3 PM Wed 97 102 SW 16 25 14110 10593 7193 Blue 18
4 PM Wed 96 99 SW 16 25 11001 7070 3670 Blue 15
5 PM Wed 95 96 WSW 14 25 7148 5228 1828 Blue 12
6 PM Wed 93 92 WSW 12 24 4860 4102 702 Blue 8
7 PM Wed 90 88 WSW 12 23 3932 3489 89 Blue 4
8 PM Wed 86 84 W 10 19 2710 3400 0 Blue 0
9 PM Wed 83 81 W 9 16 2710 3400 0 Blue 0
10 PM Wed 82 80 W 6 13 2710 3400 0 Blue 0
11 PM Wed 81 79 W 5 10 2710 3400 0 Blue 0
12 Midnight Thu 80 78 W 4 9 2710 3400 0 Blue 0
1 AM Thu 80 78 W 3 6 2710 3400 0 Blue 0
2 AM Thu 79 77 W 2 5 2710 3400 0 Blue 0
3 AM Thu 78 76 W 2 5 2710 3400 0 Blue 0
4 AM Thu 77 75 W 2 4 2710 3400 0 Blue 0
5 AM Thu 76 74 WSW 1 3 2710 3400 0 Blue 0
6 AM Thu 75 73 WSW 1 3 2710 3400 0 Blue 0
7 AM Thu 75 73 WSW 1 3 2710 3400 0 Blue 0
8 AM Thu 76 75 W 1 3 2710 3400 0 Blue 0
9 AM Thu 79 79 W 1 3 2710 3400 0 Blue 0
10 AM Thu 82 84 W 1 3 2710 3400 0 Blue 0
11 AM Thu 85 89 SSE 5 10 4112 3694 294 Blue 5
12 Noon Thu 89 94 SSE 5 10 5931 4510 1110 Blue 10
1 PM Thu 91 97 SSE 5 10 8890 5870 2470 Blue 13
2 PM Thu 93 99 SSW 10 18 11001 7070 3670 Blue 15
3 PM Thu 94 99 SSW 10 18 11001 7070 3670 Blue 15
4 PM Thu 94 97 SSW 10 18 8890 5870 2470 Blue 13
5 PM Thu 93 94 WSW 12 23 5931 4510 1110 Blue 10
6 PM Thu 90 90 WSW 12 23 4328 3811 411 Blue 6
7 PM Thu 85 83 WSW 12 23 2710 3400 0 Blue 0
8 PM Thu 82 80 WSW 10 18 2710 3400 0 Blue 0
9 PM Thu 79 77 WSW 10 18 2710 3400 0 Blue 0
10 PM Thu 78 76 WSW 10 18 2710 3400 0 Blue 0
11 PM Thu 77 75 W 5 11 2710 3400 0 Blue 0
12 Midnight Fri 76 74 W 5 11 2710 3400 0 Blue 0
1 AM Fri 75 73 W 5 11 2710 3400 0 Blue 0
2 AM Fri 74 72 WNW 3 6 2710 3400 0 Blue 0
3 AM Fri 73 71 WNW 3 6 2710 3400 0 Blue 0
4 AM Fri 72 70 WNW 3 6 2710 3400 0 Blue 0
5 AM Fri 71 69 WNW 2 4 2710 3400 0 Blue 0
6 AM Fri 70 68 WNW 2 4 2710 3400 0 Blue 0
7 AM Fri 69 67 WNW 2 4 2710 3400 0 Blue 0
8 AM Fri 70 69 N 2 3 2710 3400 0 Blue 0
9 AM Fri 72 72 N 2 3 2710 3400 0 Blue 0
10 AM Fri 76 78 N 2 3 2710 3400 0 Blue 0
11 AM Fri 80 84 SE 5 9 2710 3400 0 Blue 0
12 Noon Fri 83 88 SE 5 9 3932 3489 89 Blue 4
1 PM Fri 86 92 SE 5 9 4860 4102 702 Blue 8
2 PM Fri 87 93 S 10 17 5279 4319 919 Blue 9
3 PM Fri 88 93 S 10 17 5279 4319 919 Blue 9
4 PM Fri 87 90 S 10 17 4328 3811 411 Blue 6
5 PM Fri 86 87 SSW 11 20 3815 3400 0 Blue 3
6 PM Fri 83 83 SSW 11 20 2710 3400 0 Blue 0
7 PM Fri 79 77 SSW 11 20 2710 3400 0 Blue 0
8 PM Fri 76 74 WSW 9 17 2710 3400 0 Blue 0
9 PM Fri 74 72 WSW 9 17 2710 3400 0 Blue 0
10 PM Fri 72 70 WSW 9 17 2710 3400 0 Blue 0
11 PM Fri 71 69 W 3 8 2710 3400 0 Blue 0
12 Midnight Sat 70 68 W 3 8 2710 3400 0 Blue 0
1 AM Sat 70 68 W 3 8 2710 3400 0 Blue 0
2 AM Sat 69 67 NW 2 4 2710 3400 0 Blue 0
3 AM Sat 67 65 NW 2 4 2710 3400 0 Blue 0
4 AM Sat 65 63 NW 2 4 2710 3400 0 Blue 0
5 AM Sat 64 62 N 1 2 2710 3400 0 Blue 0
6 AM Sat 62 60 N 1 2 2710 3400 0 Blue 0
7 AM Sat 62 60 N 1 2 2710 3400 0 Blue 0
8 AM Sat 62 61 NE 2 4 2710 3400 0 Blue 0
9 AM Sat 65 65 NE 2 4 2710 3400 0 Blue 0
10 AM Sat 68 70 NE 2 4 2710 3400 0 Blue 0
11 AM Sat 71 75 E 5 9 2710 3400 0 Blue 0
12 Noon Sat 74 80 E 5 9 2710 3400 0 Blue 0
1 PM Sat 77 83 E 5 9 2710 3400 0 Blue 0
2 PM Sat 80 86 SE 6 11 3697 3400 0 Blue 2
3 PM Sat 81 86 SE 6 11 3697 3400 0 Blue 2
4 PM Sat 81 84 SE 6 11 2710 3400 0 Blue 0
5 PM Sat 80 81 S 6 13 2710 3400 0 Blue 0
6 PM Sat 79 79 S 6 13 2710 3400 0 Blue 0
7 PM Sat 76 74 S 6 13 2710 3400 0 Blue 0
8 PM Sat 74 72 SW 5 11 2710 3400 0 Blue 0
9 PM Sat 72 70 SW 5 11 2710 3400 0 Blue 0
10 PM Sat 71 69 SW 5 11 2710 3400 0 Blue 0
11 PM Sat 70 68 WNW 2 6 2710 3400 0 Blue 0
12 Midnight Sun 69 67 WNW 2 6 2710 3400 0 Blue 0
1 AM Sun 68 66 WNW 2 6 2710 3400 0 Blue 0
2 AM Sun 67 65 NNW 2 3 2710 3400 0 Blue 0
3 AM Sun 66 64 NNW 2 3 2710 3400 0 Blue 0
4 AM Sun 65 63 NNW 2 3 2710 3400 0 Blue 0
5 AM Sun 64 62 N 1 2 2710 3400 0 Blue 0
6 AM Sun 64 62 N 1 2 2710 3400 0 Blue 0
7 AM Sun 64 62 N 1 2 2710 3400 0 Blue 0
8 AM Sun 66 65 NE 2 3 2710 3400 0 Blue 0
9 AM Sun 68 68 NE 2 3 2710 3400 0 Blue 0
10 AM Sun 71 73 NE 2 3 2710 3400 0 Blue 0
11 AM Sun 74 78 E 5 9 2710 3400 0 Blue 0
12 Noon Sun 77 82 E 5 9 2710 3400 0 Blue 0
1 PM Sun 80 86 E 5 9 3697 3400 0 Blue 2
2 PM Sun 82 88 SE 6 12 3932 3489 89 Blue 4
3 PM Sun 83 88 SE 6 12 3932 3489 89 Blue 4
4 PM Sun 83 86 SE 6 12 3697 3400 0 Blue 2
5 PM Sun 82 83 S 8 13 2710 3400 0 Blue 0
6 PM Sun 80 80 S 8 13 2710 3400 0 Blue 0
7 PM Sun 78 76 S 8 13 2710 3400 0 Blue 0
8 PM Sun 75 73 SW 5 12 2710 3400 0 Blue 0
9 PM Sun 74 72 SW 5 12 2710 3400 0 Blue 0
10 PM Sun 73 71 SW 5 12 2710 3400 0 Blue 0
11 PM Sun 72 70 W 3 6 2710 3400 0 Blue 0
12 Midnight Mon 71 69 W 3 6 2710 3400 0 Blue 0
1 AM Mon 70 68 W 3 6 2710 3400 0 Blue 0
2 AM Mon 69 67 NW 2 3 2710 3400 0 Blue 0
3 AM Mon 68 66 NW 2 3 2710 3400 0 Blue 0
4 AM Mon 67 65 NW 2 3 2710 3400 0 Blue 0
5 AM Mon 67 65 N 2 3 2710 3400 0 Blue 0
6 AM Mon 66 64 N 2 3 2710 3400 0 Blue 0
7 AM Mon 66 64 N 2 3 2710 3400 0 Blue 0
8 AM Mon 68 67 NE 2 4 2710 3400 0 Blue 0
9 AM Mon 70 70 NE 2 4 2710 3400 0 Blue 0
10 AM Mon 73 75 NE 2 4 2710 3400 0 Blue 0
11 AM Mon 76 80 E 5 9 2710 3400 0 Blue 0
12 Noon Mon 79 84 E 5 9 2710 3400 0 Blue 0
1 PM Mon 82 88 E 5 9 3932 3489 89 Blue 4
2 PM Mon 84 90 SE 8 13 4328 3811 411 Blue 6
3 PM Mon 85 90 SE 8 13 4328 3811 411 Blue 6
4 PM Mon 85 88 SE 8 13 3932 3489 89 Blue 4
5 PM Mon 84 85 S 9 16 3496 3400 0 Blue 1
6 PM Mon 82 82 S 9 16 2710 3400 0 Blue 0
7 PM Mon 79 77 S 9 16 2710 3400 0 Blue 0
8 PM Mon 76 74 WSW 6 13 2710 3400 0 Blue 0
9 PM Mon 74 72 WSW 6 13 2710 3400 0 Blue 0
10 PM Mon 73 71 WSW 6 13 2710 3400 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 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]