Detailed Predictions for: St John
Launch Lat, Long, Altitude (f): 39.424433, -122.689342, 6350
LZ Altitude (f): 1185
Sounding

Station:

 KOAK

Date/Time UTC:

 250322/1200

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 35 35 WNW 10 12 4012 6350 0 Blue 0
1 AM Sat 34 34 WNW 10 12 4012 6350 0 Blue 0
2 AM Sat 34 34 W 10 12 4012 6350 0 Blue 0
3 AM Sat 35 35 WNW 10 12 4012 6350 0 Blue 0
4 AM Sat 35 35 WNW 10 12 4012 6350 0 Blue 0
5 AM Sat 35 35 WNW 10 11 4012 6350 0 Blue 0
6 AM Sat 34 34 WNW 9 11 4012 6350 0 Blue 0
7 AM Sat 35 35 WNW 9 11 4012 6350 0 Blue 0
8 AM Sat 35 35 WNW 9 11 4012 6350 0 Blue 0
9 AM Sat 36 36 WNW 8 11 4012 6350 0 Blue 0
10 AM Sat 37 37 WNW 8 11 4012 6350 0 Blue 0
11 AM Sat 37 38 WNW 6 11 4012 6350 0 Blue 0
12 Noon Sat 37 38 WNW 6 11 4012 6350 0 Blue 0
1 PM Sat 37 38 WNW 5 11 4012 6350 0 Blue 0
2 PM Sat 38 39 W 5 10 4012 6350 0 Blue 0
3 PM Sat 38 39 WNW 5 11 4012 6350 0 Blue 0
4 PM Sat 39 40 WNW 6 11 4012 6350 0 Blue 0
5 PM Sat 40 40 WNW 8 12 4012 6350 0 Blue 0
6 PM Sat 39 39 WNW 6 11 4012 6350 0 Blue 0
7 PM Sat 39 39 WNW 6 11 4012 6350 0 Blue 0
8 PM Sat 38 38 NW 6 9 4012 6350 0 Blue 0
9 PM Sat 37 37 WNW 8 10 4012 6350 0 Blue 0
10 PM Sat 37 37 WNW 9 11 4012 6350 0 Blue 0
11 PM Sat 36 36 NNW 10 12 4012 6350 0 Blue 0
12 Midnight Sun 37 37 WNW 10 12 4012 6350 0 Blue 0
1 AM Sun 36 36 NW 11 13 4012 6350 0 Blue 0
2 AM Sun 35 35 NNW 12 14 4012 6350 0 Blue 0
3 AM Sun 37 37 NW 12 14 4012 6350 0 Blue 0
4 AM Sun 37 37 NW 13 14 4012 6350 0 Blue 0
5 AM Sun 37 37 NNW 13 16 4012 6350 0 Blue 0
6 AM Sun 38 38 NNW 13 16 4012 6350 0 Blue 0
7 AM Sun 39 39 NNW 13 16 4012 6350 0 Blue 0
8 AM Sun 40 40 NW 13 17 4012 6350 0 Blue 0
9 AM Sun 43 44 NW 13 17 4696 6350 0 Blue 0
10 AM Sun 46 48 NW 13 17 6225 6350 0 Blue 4
11 AM Sun 47 50 N 12 18 6504 6350 0 Blue 6
12 Noon Sun 49 53 N 12 18 7136 6494 144 Blue 9
1 PM Sun 51 56 N 12 18 7942 7112 762 Blue 12
2 PM Sun 53 57 N 11 17 8211 7380 1030 Blue 13
3 PM Sun 54 57 N 11 17 8211 7380 1030 Blue 13
4 PM Sun 55 57 N 11 17 8211 7380 1030 Blue 13
5 PM Sun 54 55 N 12 18 7675 6845 495 Blue 11
6 PM Sun 53 53 N 12 18 7136 6494 144 Blue 9
7 PM Sun 51 51 N 12 18 6644 6350 0 Blue 7
8 PM Sun 49 49 NW 9 12 6364 6350 0 Blue 5
9 PM Sun 48 48 NW 9 12 6225 6350 0 Blue 4
10 PM Sun 47 47 NW 9 12 6085 6350 0 Blue 3
11 PM Sun 46 46 NW 13 17 5759 6350 0 Blue 2
12 Midnight Mon 46 46 NW 13 17 5759 6350 0 Blue 2
1 AM Mon 46 46 NW 13 17 5759 6350 0 Blue 2
2 AM Mon 46 46 NW 13 16 5759 6350 0 Blue 2
3 AM Mon 46 46 NW 13 16 5759 6350 0 Blue 2
4 AM Mon 46 46 NW 13 16 5759 6350 0 Blue 2
5 AM Mon 46 46 NW 11 13 5759 6350 0 Blue 2
6 AM Mon 46 46 NW 11 13 5759 6350 0 Blue 2
7 AM Mon 46 46 NW 11 13 5759 6350 0 Blue 2
8 AM Mon 47 47 NW 10 12 6085 6350 0 Blue 3
9 AM Mon 50 51 NW 10 12 6644 6350 0 Blue 7
10 AM Mon 52 54 NW 10 12 7406 6633 283 Blue 10
11 AM Mon 55 59 N 9 12 8754 7911 1561 Blue 15
12 Noon Mon 56 61 N 9 12 9292 8447 2097 Blue 17
1 PM Mon 57 62 N 9 12 9558 8716 2366 Blue 18
2 PM Mon 58 63 NE 8 12 9823 8983 2633 Blue 19
3 PM Mon 59 63 NE 8 12 9823 8983 2633 Blue 19
4 PM Mon 60 63 NE 8 12 9823 8983 2633 Blue 19
5 PM Mon 59 60 NE 9 13 9024 8176 1826 Blue 16
6 PM Mon 58 58 NE 9 13 8483 7646 1296 Blue 14
7 PM Mon 55 55 NE 9 13 7675 6845 495 Blue 11
8 PM Mon 53 53 WNW 4 6 7136 6494 144 Blue 9
9 PM Mon 51 51 WNW 4 6 6644 6350 0 Blue 7
10 PM Mon 50 50 WNW 4 6 6504 6350 0 Blue 6
11 PM Mon 49 49 NW 8 10 6364 6350 0 Blue 5
12 Midnight Tue 49 49 NW 8 10 6364 6350 0 Blue 5
1 AM Tue 49 49 NW 8 10 6364 6350 0 Blue 5
2 AM Tue 48 48 NW 9 11 6225 6350 0 Blue 4
3 AM Tue 48 48 NW 9 11 6225 6350 0 Blue 4
4 AM Tue 47 47 NW 9 11 6085 6350 0 Blue 3
5 AM Tue 47 47 NW 9 11 6085 6350 0 Blue 3
6 AM Tue 47 47 NW 9 11 6085 6350 0 Blue 3
7 AM Tue 48 48 NW 9 11 6225 6350 0 Blue 4
8 AM Tue 49 49 NNW 9 11 6364 6350 0 Blue 5
9 AM Tue 51 52 NNW 9 11 6867 6355 5 Blue 8
10 AM Tue 54 56 NNW 9 11 7942 7112 762 Blue 12
11 AM Tue 56 59 NNE 8 11 8754 7911 1561 Blue 15
12 Noon Tue 57 61 NNE 8 11 9292 8447 2097 Blue 17
1 PM Tue 58 63 NNE 8 11 9823 8983 2633 Blue 19
2 PM Tue 59 63 SE 10 16 9823 8983 2633 Blue 19
3 PM Tue 59 62 SE 10 16 9558 8716 2366 Blue 18
4 PM Tue 60 62 SE 10 16 9558 8716 2366 Blue 18
5 PM Tue 59 60 SW 13 19 9024 8176 1826 Blue 16
6 PM Tue 57 57 SW 13 19 8211 7380 1030 Blue 13
7 PM Tue 54 54 SW 13 19 7406 6633 283 Blue 10
8 PM Tue 52 52 W 10 12 6867 6355 5 Blue 8
9 PM Tue 51 51 W 10 12 6644 6350 0 Blue 7
10 PM Tue 50 50 W 10 12 6504 6350 0 Blue 6
11 PM Tue 49 49 WNW 9 10 6364 6350 0 Blue 5
12 Midnight Wed 49 49 WNW 9 10 6364 6350 0 Blue 5
1 AM Wed 48 48 WNW 9 10 6225 6350 0 Blue 4
2 AM Wed 48 48 WNW 9 10 6225 6350 0 Blue 4
3 AM Wed 47 47 WNW 9 10 6085 6350 0 Blue 3
4 AM Wed 46 46 WNW 9 10 5759 6350 0 Blue 2
5 AM Wed 45 45 WNW 10 10 5334 6350 0 Blue 1
6 AM Wed 45 45 WNW 10 10 5334 6350 0 Blue 1
7 AM Wed 46 46 WNW 10 10 5759 6350 0 Blue 2
8 AM Wed 46 46 WNW 12 14 5759 6350 0 Blue 2
9 AM Wed 47 47 WNW 12 14 6085 6350 0 Blue 3
10 AM Wed 48 49 WNW 12 14 6364 6350 0 Blue 5
11 AM Wed 49 50 SW 18 26 6504 6350 0 Blue 6
12 Noon Wed 50 52 SW 18 26 6867 6355 5 Blue 8
1 PM Wed 50 52 SW 18 26 6867 6355 5 Blue 8
2 PM Wed 49 51 SW 24 36 6644 6350 0 Blue 7
3 PM Wed 48 49 SW 24 36 6364 6350 0 Blue 5
4 PM Wed 47 48 SW 24 36 6225 6350 0 Blue 4
5 PM Wed 45 45 WSW 29 40 5334 6350 0 Blue 1
6 PM Wed 43 43 WSW 29 40 4012 6350 0 Blue 0
7 PM Wed 41 41 WSW 29 40 4012 6350 0 Blue 0
8 PM Wed 40 40 WSW 28 36 4012 6350 0 Blue 0
9 PM Wed 39 39 WSW 28 36 4012 6350 0 Blue 0
10 PM Wed 39 39 WSW 28 36 4012 6350 0 Blue 0
11 PM Wed 38 38 WSW 25 32 4012 6350 0 Blue 0
12 Midnight Thu 37 37 WSW 25 32 4012 6350 0 Blue 0
1 AM Thu 37 37 WSW 25 32 4012 6350 0 Blue 0
2 AM Thu 36 36 WSW 21 28 4012 6350 0 Blue 0
3 AM Thu 35 35 WSW 21 28 4012 6350 0 Blue 0
4 AM Thu 35 35 WSW 21 28 4012 6350 0 Blue 0
5 AM Thu 34 34 WSW 19 25 4012 6350 0 Blue 0
6 AM Thu 34 34 WSW 19 25 4012 6350 0 Blue 0
7 AM Thu 33 33 WSW 19 25 4012 6350 0 Blue 0
8 AM Thu 33 33 WSW 17 21 4012 6350 0 Blue 0
9 AM Thu 33 33 WSW 17 21 4012 6350 0 Blue 0
10 AM Thu 34 34 WSW 17 21 4012 6350 0 Blue 0
11 AM Thu 35 36 WSW 18 26 4012 6350 0 Blue 0
12 Noon Thu 36 37 WSW 18 26 4012 6350 0 Blue 0
1 PM Thu 37 38 WSW 18 26 4012 6350 0 Blue 0
2 PM Thu 38 39 WSW 19 28 4012 6350 0 Blue 0
3 PM Thu 38 39 WSW 19 28 4012 6350 0 Blue 0
4 PM Thu 38 38 WSW 19 28 4012 6350 0 Blue 0
5 PM Thu 37 38 W 24 32 4012 6350 0 Blue 0
6 PM Thu 36 36 W 24 32 4012 6350 0 Blue 0
7 PM Thu 35 35 W 24 32 4012 6350 0 Blue 0
8 PM Thu 34 34 W 20 27 4012 6350 0 Blue 0
9 PM Thu 34 34 W 20 27 4012 6350 0 Blue 0
10 PM Thu 33 33 W 20 27 4012 6350 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]