Detailed Predictions for: Potato Hill
Launch Altitude (f): 3400
LZ Altitude (f): 1700
Sounding

Station:

 KOAK

Date/Time:

 N/A

Temp/Wind data from:

NOAA Digital Forecast

Time
(Local)		 High
Temp
Puddle
Temp
Wind
 (mph)		 Thermal
Ceiling
(ft)		 Soaring
Ceiling
(ft)		 Above
Launch
(ft)		 Thermal
Type		 Thermal
Index
(F)
12 Midnight Mon 69 69 WNW 6 N/A N/A N/A N/A N/A
1 AM Mon 67 67 WNW 6 N/A N/A N/A N/A N/A
2 AM Mon 66 66 NNW 4 N/A N/A N/A N/A N/A
3 AM Mon 65 65 NNW 4 N/A N/A N/A N/A N/A
4 AM Mon 64 64 NNW 4 N/A N/A N/A N/A N/A
5 AM Mon 62 62 NNW 3 N/A N/A N/A N/A N/A
6 AM Mon 63 63 NNW 3 N/A N/A N/A N/A N/A
7 AM Mon 64 64 NNW 3 N/A N/A N/A N/A N/A
8 AM Mon 67 67 W 3 N/A N/A N/A N/A N/A
9 AM Mon 72 73 W 3 N/A N/A N/A N/A N/A
10 AM Mon 78 81 W 3 N/A N/A N/A N/A N/A
11 AM Mon 81 85 ENE 5 N/A N/A N/A N/A N/A
12 Noon Mon 86 92 ENE 5 N/A N/A N/A N/A N/A
1 PM Mon 90 96 ENE 5 N/A N/A N/A N/A N/A
2 PM Mon 92 98 ESE 6 N/A N/A N/A N/A N/A
3 PM Mon 93 98 ESE 6 N/A N/A N/A N/A N/A
4 PM Mon 94 97 ESE 6 N/A N/A N/A N/A N/A
5 PM Mon 94 96 SSW 5 N/A N/A N/A N/A N/A
6 PM Mon 92 92 SSW 5 N/A N/A N/A N/A N/A
7 PM Mon 86 86 SSW 5 N/A N/A N/A N/A N/A
8 PM Mon 76 76 W 6 N/A N/A N/A N/A N/A
9 PM Mon 71 71 W 6 N/A N/A N/A N/A N/A
10 PM Mon 67 67 W 6 N/A N/A N/A N/A N/A
11 PM Mon 65 65 W 7 N/A N/A N/A N/A N/A
12 Midnight Tue 63 63 W 7 N/A N/A N/A N/A N/A
1 AM Tue 61 61 W 7 N/A N/A N/A N/A N/A
2 AM Tue 60 60 NW 7 N/A N/A N/A N/A N/A
3 AM Tue 59 59 NW 7 N/A N/A N/A N/A N/A
4 AM Tue 58 58 NW 7 N/A N/A N/A N/A N/A
5 AM Tue 56 56 NW 5 N/A N/A N/A N/A N/A
6 AM Tue 57 57 NW 5 N/A N/A N/A N/A N/A
7 AM Tue 58 58 NW 5 N/A N/A N/A N/A N/A
8 AM Tue 61 61 NW 2 N/A N/A N/A N/A N/A
9 AM Tue 66 67 NW 2 N/A N/A N/A N/A N/A
10 AM Tue 72 75 NW 2 N/A N/A N/A N/A N/A
11 AM Tue 75 79 S 6 N/A N/A N/A N/A N/A
12 Noon Tue 80 86 S 6 N/A N/A N/A N/A N/A
1 PM Tue 84 90 S 6 N/A N/A N/A N/A N/A
2 PM Tue 86 92 S 7 N/A N/A N/A N/A N/A
3 PM Tue 87 92 S 7 N/A N/A N/A N/A N/A
4 PM Tue 88 91 S 7 N/A N/A N/A N/A N/A
5 PM Tue 88 90 SSW 6 N/A N/A N/A N/A N/A
6 PM Tue 86 86 SSW 6 N/A N/A N/A N/A N/A
7 PM Tue 81 81 SSW 6 N/A N/A N/A N/A N/A
8 PM Tue 72 72 W 5 N/A N/A N/A N/A N/A
9 PM Tue 66 66 W 5 N/A N/A N/A N/A N/A
10 PM Tue 63 63 W 5 N/A N/A N/A N/A N/A
11 PM Tue 61 61 WSW 4 N/A N/A N/A N/A N/A
12 Midnight Wed 59 59 WSW 4 N/A N/A N/A N/A N/A
1 AM Wed 58 58 WSW 4 N/A N/A N/A N/A N/A
2 AM Wed 57 57 WSW 5 N/A N/A N/A N/A N/A
3 AM Wed 56 56 WSW 5 N/A N/A N/A N/A N/A
4 AM Wed 55 55 WSW 5 N/A N/A N/A N/A N/A
5 AM Wed 53 53 WSW 3 N/A N/A N/A N/A N/A
6 AM Wed 54 54 WSW 3 N/A N/A N/A N/A N/A
7 AM Wed 55 55 WSW 3 N/A N/A N/A N/A N/A
8 AM Wed 59 59 WSW 3 N/A N/A N/A N/A N/A
9 AM Wed 65 66 WSW 3 N/A N/A N/A N/A N/A
10 AM Wed 72 75 WSW 3 N/A N/A N/A N/A N/A
11 AM Wed 75 79 NE 4 N/A N/A N/A N/A N/A
12 Noon Wed 81 87 NE 4 N/A N/A N/A N/A N/A
1 PM Wed 86 92 NE 4 N/A N/A N/A N/A N/A
2 PM Wed 88 94 NE 4 N/A N/A N/A N/A N/A
3 PM Wed 90 95 NE 4 N/A N/A N/A N/A N/A
4 PM Wed 91 94 NE 4 N/A N/A N/A N/A N/A
5 PM Wed 91 93 W 4 N/A N/A N/A N/A N/A
6 PM Wed 89 89 W 4 N/A N/A N/A N/A N/A
7 PM Wed 84 84 W 4 N/A N/A N/A N/A N/A
8 PM Wed 74 74 W 4 N/A N/A N/A N/A N/A
9 PM Wed 69 69 W 4 N/A N/A N/A N/A N/A
10 PM Wed 66 66 W 4 N/A N/A N/A N/A N/A
11 PM Wed 63 63 WNW 5 N/A N/A N/A N/A N/A
12 Midnight Thu 62 62 WNW 5 N/A N/A N/A N/A N/A
1 AM Thu 60 60 WNW 5 N/A N/A N/A N/A N/A
2 AM Thu 59 59 WNW 5 N/A N/A N/A N/A N/A
3 AM Thu 58 58 WNW 5 N/A N/A N/A N/A N/A
4 AM Thu 57 57 WNW 5 N/A N/A N/A N/A N/A
5 AM Thu 55 55 N 4 N/A N/A N/A N/A N/A
6 AM Thu 56 56 N 4 N/A N/A N/A N/A N/A
7 AM Thu 57 57 N 4 N/A N/A N/A N/A N/A
8 AM Thu 61 61 N 4 N/A N/A N/A N/A N/A
9 AM Thu 66 67 N 4 N/A N/A N/A N/A N/A
10 AM Thu 73 76 N 4 N/A N/A N/A N/A N/A
11 AM Thu 76 80 ENE 4 N/A N/A N/A N/A N/A
12 Noon Thu 82 88 ENE 4 N/A N/A N/A N/A N/A
1 PM Thu 86 92 ENE 4 N/A N/A N/A N/A N/A
2 PM Thu 88 94 ENE 4 N/A N/A N/A N/A N/A
3 PM Thu 90 95 ENE 4 N/A N/A N/A N/A N/A
4 PM Thu 91 94 ENE 4 N/A N/A N/A N/A N/A
5 PM Thu 91 93 WSW 5 N/A N/A N/A N/A N/A
6 PM Thu 88 88 WSW 5 N/A N/A N/A N/A N/A
7 PM Thu 83 83 WSW 5 N/A N/A N/A N/A N/A
8 PM Thu 73 73 WSW 5 N/A N/A N/A N/A N/A
9 PM Thu 67 67 WSW 5 N/A N/A N/A N/A N/A
10 PM Thu 63 63 WSW 5 N/A N/A N/A N/A N/A
11 PM Thu 61 61 WNW 6 N/A N/A N/A N/A N/A
12 Midnight Fri 59 59 WNW 6 N/A N/A N/A N/A N/A
1 AM Fri 57 57 WNW 6 N/A N/A N/A N/A N/A
2 AM Fri 56 56 WNW 6 N/A N/A N/A N/A N/A
3 AM Fri 55 55 WNW 6 N/A N/A N/A N/A N/A
4 AM Fri 54 54 WNW 6 N/A N/A N/A N/A N/A
5 AM Fri 52 52 NNW 3 N/A N/A N/A N/A N/A
6 AM Fri 53 53 NNW 3 N/A N/A N/A N/A N/A
7 AM Fri 54 54 NNW 3 N/A N/A N/A N/A N/A
8 AM Fri 58 58 NNW 3 N/A N/A N/A N/A N/A
9 AM Fri 64 65 NNW 3 N/A N/A N/A N/A N/A
10 AM Fri 71 74 NNW 3 N/A N/A N/A N/A N/A
11 AM Fri 75 79 SSE 2 N/A N/A N/A N/A N/A
12 Noon Fri 81 87 SSE 2 N/A N/A N/A N/A N/A
1 PM Fri 86 92 SSE 2 N/A N/A N/A N/A N/A
2 PM Fri 88 94 SSE 2 N/A N/A N/A N/A N/A
3 PM Fri 90 95 SSE 2 N/A N/A N/A N/A N/A
4 PM Fri 91 94 SSE 2 N/A N/A N/A N/A N/A
5 PM Fri 91 93 WSW 7 N/A N/A N/A N/A N/A
6 PM Fri 88 88 WSW 7 N/A N/A N/A N/A N/A
7 PM Fri 83 83 WSW 7 N/A N/A N/A N/A N/A
8 PM Fri 73 73 WSW 7 N/A N/A N/A N/A N/A
9 PM Fri 67 67 WSW 7 N/A N/A N/A N/A N/A
10 PM Fri 63 63 WSW 7 N/A N/A N/A N/A N/A
11 PM Fri 61 61 W 5 N/A N/A N/A N/A N/A
12 Midnight Sat 59 59 W 5 N/A N/A N/A N/A N/A
1 AM Sat 57 57 W 5 N/A N/A N/A N/A N/A
2 AM Sat 56 56 W 5 N/A N/A N/A N/A N/A
3 AM Sat 55 55 W 5 N/A N/A N/A N/A N/A
4 AM Sat 54 54 W 5 N/A N/A N/A N/A N/A
5 AM Sat 52 52 WSW 3 N/A N/A N/A N/A N/A
6 AM Sat 53 53 WSW 3 N/A N/A N/A N/A N/A
7 AM Sat 54 54 WSW 3 N/A N/A N/A N/A N/A
8 AM Sat 57 57 WSW 3 N/A N/A N/A N/A N/A
9 AM Sat 63 64 WSW 3 N/A N/A N/A N/A N/A
10 AM Sat 69 72 WSW 3 N/A N/A N/A N/A N/A
11 AM Sat 72 76 ESE 3 N/A N/A N/A N/A N/A
12 Noon Sat 77 83 ESE 3 N/A N/A N/A N/A N/A
1 PM Sat 82 88 ESE 3 N/A N/A N/A N/A N/A
2 PM Sat 84 90 ESE 3 N/A N/A N/A N/A N/A
3 PM Sat 85 90 ESE 3 N/A N/A N/A N/A N/A
4 PM Sat 86 89 ESE 3 N/A N/A N/A N/A N/A

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 Weather Channel website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the Weather Channel 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 Weather Channel 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 ac_soaring@yahoo.com