Detailed Predictions for: Ed Levin
Launch Lat, Long, Altitude (f): 37.475633, -121.86, 2150
LZ Altitude (f): 400
Sounding

Station:

KOAK

Date/Time:

12 MAY 2021

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 63 63 NNW 2 3 1621 2150 0 Blue 0
1 AM Wed 62 62 NNW 2 2 1621 2150 0 Blue 0
2 AM Wed 61 61 NW 1 2 1621 2150 0 Blue 0
3 AM Wed 61 61 NW 1 1 1621 2150 0 Blue 0
4 AM Wed 60 60 W 1 1 1621 2150 0 Blue 0
5 AM Wed 60 60 SSW 1 2 1621 2150 0 Blue 0
6 AM Wed 60 60 S 2 3 1621 2150 0 Blue 0
7 AM Wed 60 60 S 3 4 1621 2150 0 Blue 0
8 AM Wed 65 66 S 4 6 1621 2150 0 Blue 0
9 AM Wed 67 70 SSW 4 6 1621 2150 0 Blue 0
10 AM Wed 70 75 SSW 5 9 2165 2150 0 Blue 1
11 AM Wed 72 78 SW 6 10 3092 2162 12 Blue 4
12 Noon Wed 73 81 WSW 6 10 4639 3079 929 Blue 7
1 PM Wed 75 83 WSW 8 11 5774 3734 1584 Blue 9
2 PM Wed 77 85 W 8 11 6848 5463 3313 Blue 11
3 PM Wed 78 84 W 8 11 6051 4519 2369 Blue 10
4 PM Wed 77 81 W 8 12 4639 3079 929 Blue 7
5 PM Wed 76 79 W 8 12 3424 2443 293 Blue 5
6 PM Wed 75 76 WNW 6 10 2448 2150 0 Blue 2
7 PM Wed 72 72 WNW 5 9 1775 2150 0 Blue 0
8 PM Wed 67 67 WNW 4 6 1621 2150 0 Blue 0
9 PM Wed 64 64 WNW 4 6 1621 2150 0 Blue 0
10 PM Wed 61 61 WNW 2 4 1621 2150 0 Blue 0
11 PM Wed 59 59 SW 2 3 1621 2150 0 Blue 0
12 Midnight Thu 58 58 SSW 3 4 1621 2150 0 Blue 0
1 AM Thu 58 58 SSW 3 4 1621 2150 0 Blue 0
2 AM Thu 57 57 SSW 3 5 1621 2150 0 Blue 0
3 AM Thu 56 56 S 4 6 1621 2150 0 Blue 0
4 AM Thu 56 56 S 4 6 1621 2150 0 Blue 0
5 AM Thu 55 55 SSW 4 6 1621 2150 0 Blue 0
6 AM Thu 54 54 S 4 6 1621 2150 0 Blue 0
7 AM Thu 57 57 S 4 6 1621 2150 0 Blue 0
8 AM Thu 60 61 SSW 4 8 1621 2150 0 Blue 0
9 AM Thu 62 65 SSW 5 8 1621 2150 0 Blue 0
10 AM Thu 65 69 SW 5 9 1621 2150 0 Blue 0
11 AM Thu 68 74 WSW 6 10 1949 2150 0 Blue 0
12 Noon Thu 71 78 WSW 6 10 3092 2162 12 Blue 4
1 PM Thu 74 81 WSW 6 10 4639 3079 929 Blue 7
2 PM Thu 75 82 W 9 12 5496 3408 1258 Blue 8
3 PM Thu 75 81 W 9 12 4639 3079 929 Blue 7
4 PM Thu 75 79 W 9 12 3424 2443 293 Blue 5
5 PM Thu 73 75 W 6 10 2165 2150 0 Blue 1
6 PM Thu 71 72 W 6 10 1775 2150 0 Blue 0
7 PM Thu 67 67 W 6 10 1621 2150 0 Blue 0
8 PM Thu 64 64 W 2 4 1621 2150 0 Blue 0
9 PM Thu 61 61 W 2 4 1621 2150 0 Blue 0
10 PM Thu 59 59 W 2 4 1621 2150 0 Blue 0
11 PM Thu 58 58 SW 3 4 1621 2150 0 Blue 0
12 Midnight Fri 56 56 SW 3 4 1621 2150 0 Blue 0
1 AM Fri 55 55 SW 3 4 1621 2150 0 Blue 0
2 AM Fri 54 54 SSW 3 5 1621 2150 0 Blue 0
3 AM Fri 53 53 SSW 3 5 1621 2150 0 Blue 0
4 AM Fri 52 52 SSW 3 5 1621 2150 0 Blue 0
5 AM Fri 52 52 SSW 4 6 1621 2150 0 Blue 0
6 AM Fri 52 52 SSW 4 6 1621 2150 0 Blue 0
7 AM Fri 53 53 SSW 4 6 1621 2150 0 Blue 0
8 AM Fri 55 56 SSW 6 10 1621 2150 0 Blue 0
9 AM Fri 58 60 SSW 6 10 1621 2150 0 Blue 0
10 AM Fri 60 64 SSW 6 10 1621 2150 0 Blue 0
11 AM Fri 63 69 SW 8 11 1621 2150 0 Blue 0
12 Noon Fri 66 73 SW 8 11 1862 2150 0 Blue 0
1 PM Fri 68 76 SW 8 11 2448 2150 0 Blue 2
2 PM Fri 69 76 W 9 13 2448 2150 0 Blue 2
3 PM Fri 68 74 W 9 13 1949 2150 0 Blue 0
4 PM Fri 67 71 W 9 13 1688 2150 0 Blue 0
5 PM Fri 64 66 W 9 13 1621 2150 0 Blue 0
6 PM Fri 62 63 W 9 13 1621 2150 0 Blue 0
7 PM Fri 59 59 W 9 13 1621 2150 0 Blue 0
8 PM Fri 57 57 W 5 9 1621 2150 0 Blue 0
9 PM Fri 54 54 W 5 9 1621 2150 0 Blue 0
10 PM Fri 53 53 W 5 9 1621 2150 0 Blue 0
11 PM Fri 51 51 SSW 4 5 1621 2150 0 Blue 0
12 Midnight Sat 51 51 SSW 4 5 1621 2150 0 Blue 0
1 AM Sat 50 50 SSW 4 5 1621 2150 0 Blue 0
2 AM Sat 50 50 S 6 10 1621 2150 0 Blue 0
3 AM Sat 50 50 S 6 10 1621 2150 0 Blue 0
4 AM Sat 49 49 S 6 10 1621 2150 0 Blue 0
5 AM Sat 49 49 S 8 12 1621 2150 0 Blue 0
6 AM Sat 50 50 S 8 12 1621 2150 0 Blue 0
7 AM Sat 51 51 S 8 12 1621 2150 0 Blue 0
8 AM Sat 52 52 S 8 11 1621 2150 0 Blue 0
9 AM Sat 54 56 S 8 11 1621 2150 0 Blue 0
10 AM Sat 57 60 S 8 11 1621 2150 0 Blue 0
11 AM Sat 60 65 WSW 6 10 1621 2150 0 Blue 0
12 Noon Sat 63 69 WSW 6 10 1621 2150 0 Blue 0
1 PM Sat 66 73 WSW 6 10 1862 2150 0 Blue 0
2 PM Sat 68 75 W 6 10 2165 2150 0 Blue 1
3 PM Sat 69 75 W 6 10 2165 2150 0 Blue 1
4 PM Sat 69 73 W 6 10 1862 2150 0 Blue 0
5 PM Sat 68 70 W 9 13 1621 2150 0 Blue 0
6 PM Sat 66 67 W 9 13 1621 2150 0 Blue 0
7 PM Sat 64 64 W 9 13 1621 2150 0 Blue 0
8 PM Sat 62 62 WSW 8 11 1621 2150 0 Blue 0
9 PM Sat 59 59 WSW 8 11 1621 2150 0 Blue 0
10 PM Sat 57 57 WSW 8 11 1621 2150 0 Blue 0
11 PM Sat 55 55 SSW 8 12 1621 2150 0 Blue 0
12 Midnight Sun 54 54 SSW 8 12 1621 2150 0 Blue 0
1 AM Sun 53 53 SSW 8 12 1621 2150 0 Blue 0
2 AM Sun 53 53 S 8 12 1621 2150 0 Blue 0
3 AM Sun 52 52 S 8 12 1621 2150 0 Blue 0
4 AM Sun 51 51 S 8 12 1621 2150 0 Blue 0
5 AM Sun 51 51 S 9 14 1621 2150 0 Blue 0
6 AM Sun 51 51 S 9 14 1621 2150 0 Blue 0
7 AM Sun 51 51 S 9 14 1621 2150 0 Blue 0
8 AM Sun 53 54 S 9 14 1621 2150 0 Blue 0
9 AM Sun 55 57 S 9 14 1621 2150 0 Blue 0
10 AM Sun 58 61 S 9 14 1621 2150 0 Blue 0
11 AM Sun 62 68 SW 6 11 1621 2150 0 Blue 0
12 Noon Sun 65 72 SW 6 11 1775 2150 0 Blue 0
1 PM Sun 68 75 SW 6 11 2165 2150 0 Blue 1
2 PM Sun 69 77 W 6 11 2757 2150 0 Blue 3
3 PM Sun 70 76 W 6 11 2448 2150 0 Blue 2
4 PM Sun 70 74 W 6 11 1949 2150 0 Blue 0
5 PM Sun 69 71 W 10 16 1688 2150 0 Blue 0
6 PM Sun 67 68 W 10 16 1621 2150 0 Blue 0
7 PM Sun 64 64 W 10 16 1621 2150 0 Blue 0
8 PM Sun 61 61 WSW 9 14 1621 2150 0 Blue 0
9 PM Sun 59 59 WSW 9 14 1621 2150 0 Blue 0
10 PM Sun 56 56 WSW 9 14 1621 2150 0 Blue 0
11 PM Sun 54 54 SSW 8 12 1621 2150 0 Blue 0
12 Midnight Mon 53 53 SSW 8 12 1621 2150 0 Blue 0
1 AM Mon 52 52 SSW 8 12 1621 2150 0 Blue 0
2 AM Mon 51 51 SSW 9 14 1621 2150 0 Blue 0
3 AM Mon 51 51 SSW 9 14 1621 2150 0 Blue 0
4 AM Mon 50 50 SSW 9 14 1621 2150 0 Blue 0
5 AM Mon 50 50 SSW 10 16 1621 2150 0 Blue 0
6 AM Mon 50 50 SSW 10 16 1621 2150 0 Blue 0
7 AM Mon 51 51 SSW 10 16 1621 2150 0 Blue 0
8 AM Mon 52 53 SSW 8 12 1621 2150 0 Blue 0
9 AM Mon 55 57 SSW 8 12 1621 2150 0 Blue 0
10 AM Mon 58 61 SSW 8 12 1621 2150 0 Blue 0
11 AM Mon 61 67 WSW 8 11 1621 2150 0 Blue 0
12 Noon Mon 64 71 WSW 8 11 1688 2150 0 Blue 0
1 PM Mon 66 73 WSW 8 11 1862 2150 0 Blue 0
2 PM Mon 68 75 W 9 13 2165 2150 0 Blue 1
3 PM Mon 68 74 W 9 13 1949 2150 0 Blue 0
4 PM Mon 68 72 W 9 13 1775 2150 0 Blue 0
5 PM Mon 66 68 W 12 18 1621 2150 0 Blue 0
6 PM Mon 64 65 W 12 18 1621 2150 0 Blue 0
7 PM Mon 61 61 W 12 18 1621 2150 0 Blue 0
8 PM Mon 59 59 W 11 17 1621 2150 0 Blue 0
9 PM Mon 56 56 W 11 17 1621 2150 0 Blue 0
10 PM Mon 55 55 W 11 17 1621 2150 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 ac_soaring@yahoo.com