Detailed Predictions for: St John
Launch Altitude (f): 6350
LZ Altitude (f): 1185
Sounding

Station:

KOAK

Date/Time:

19 NOV 2017

Temp/Wind data from:

NOAA Digital Forecast

Site Forecasts
Time
(Local)
High
Temp

Puddle
Temp

Wind
(mph)
Thermal
Ceiling

(ft)
Soaring
Ceiling

(ft)
Above
Launch

(ft)
Thermal
Type
Thermal
Index

(F)
4 AM Sun 37 37 N 9 4154 6350 0 Blue 0
5 AM Sun 36 36 N 9 4154 6350 0 Blue 0
6 AM Sun 36 36 N 9 4154 6350 0 Blue 0
7 AM Sun 37 37 NW 9 4154 6350 0 Blue 0
8 AM Sun 38 38 NW 9 4154 6350 0 Blue 0
9 AM Sun 41 41 NW 9 4154 6350 0 Blue 0
10 AM Sun 43 44 W 9 4154 6350 0 Blue 0
11 AM Sun 45 46 W 9 4210 6350 0 Blue 0
12 Noon Sun 47 48 W 9 4335 6350 0 Blue 0
1 PM Sun 47 48 SW 12 4335 6350 0 Blue 0
2 PM Sun 46 47 SW 12 4273 6350 0 Blue 0
3 PM Sun 45 45 SW 12 4154 6350 0 Blue 0
4 PM Sun 44 44 SW 10 4154 6350 0 Blue 0
5 PM Sun 43 43 SW 10 4154 6350 0 Blue 0
6 PM Sun 42 42 SW 10 4154 6350 0 Blue 0
7 PM Sun 41 41 SW 12 4154 6350 0 Blue 0
8 PM Sun 41 41 SW 12 4154 6350 0 Blue 0
9 PM Sun 41 41 SW 12 4154 6350 0 Blue 0
10 PM Sun 41 41 SW 10 4154 6350 0 Blue 0
11 PM Sun 42 42 SW 10 4154 6350 0 Blue 0
12 Midnight Mon 42 42 SW 10 4154 6350 0 Blue 0
1 AM Mon 42 42 SW 10 4154 6350 0 Blue 0
2 AM Mon 43 43 SW 10 4154 6350 0 Blue 0
3 AM Mon 43 43 SW 10 4154 6350 0 Blue 0
4 AM Mon 43 43 SW 13 4154 6350 0 Blue 0
5 AM Mon 44 44 SW 13 4154 6350 0 Blue 0
6 AM Mon 44 44 SW 13 4154 6350 0 Blue 0
7 AM Mon 44 44 SW 13 4154 6350 0 Blue 0
8 AM Mon 44 44 SW 13 4154 6350 0 Blue 0
9 AM Mon 43 43 SW 13 4154 6350 0 Blue 0
10 AM Mon 43 43 SW 14 4154 6350 0 Blue 0
11 AM Mon 43 43 SW 14 4154 6350 0 Blue 0
12 Noon Mon 44 44 SW 14 4154 6350 0 Blue 0
1 PM Mon 44 44 SW 14 4154 6350 0 Blue 0
2 PM Mon 44 44 SW 14 4154 6350 0 Blue 0
3 PM Mon 44 44 SW 14 4154 6350 0 Blue 0
4 PM Mon 44 44 SW 9 4154 6350 0 Blue 0
5 PM Mon 45 45 SW 9 4154 6350 0 Blue 0
6 PM Mon 46 46 SW 9 4210 6350 0 Blue 0
7 PM Mon 47 47 SW 9 4273 6350 0 Blue 0
8 PM Mon 46 46 SW 9 4210 6350 0 Blue 0
9 PM Mon 46 46 SW 9 4210 6350 0 Blue 0
10 PM Mon 47 47 SE 10 4273 6350 0 Blue 0
11 PM Mon 47 47 SE 10 4273 6350 0 Blue 0
12 Midnight Tue 47 47 SE 10 4273 6350 0 Blue 0
1 AM Tue 47 47 SE 10 4273 6350 0 Blue 0
2 AM Tue 47 47 SE 10 4273 6350 0 Blue 0
3 AM Tue 47 47 SE 10 4273 6350 0 Blue 0
4 AM Tue 47 47 S 12 4273 6350 0 Blue 0
5 AM Tue 46 46 S 12 4210 6350 0 Blue 0
6 AM Tue 46 46 S 12 4210 6350 0 Blue 0
7 AM Tue 47 47 S 12 4273 6350 0 Blue 0
8 AM Tue 48 48 S 12 4335 6350 0 Blue 0
9 AM Tue 50 50 S 12 4461 6350 0 Blue 0
10 AM Tue 52 52 S 13 4620 6350 0 Blue 2
11 AM Tue 54 54 S 13 5002 6350 0 Blue 4
12 Noon Tue 55 55 S 13 5172 6350 0 Blue 5
1 PM Tue 55 55 S 13 5172 6350 0 Blue 5
2 PM Tue 55 55 S 13 5172 6350 0 Blue 5
3 PM Tue 54 54 S 13 5002 6350 0 Blue 4
4 PM Tue 53 53 S 12 4700 6350 0 Blue 3
5 PM Tue 52 52 S 12 4620 6350 0 Blue 2
6 PM Tue 51 51 S 12 4540 6350 0 Blue 1
7 PM Tue 51 51 S 12 4540 6350 0 Blue 1
8 PM Tue 50 50 S 12 4461 6350 0 Blue 0
9 PM Tue 50 50 S 12 4461 6350 0 Blue 0
10 PM Tue 50 50 S 12 4461 6350 0 Blue 0
11 PM Tue 50 50 S 12 4461 6350 0 Blue 0
12 Midnight Wed 50 50 S 12 4461 6350 0 Blue 0
1 AM Wed 50 50 S 12 4461 6350 0 Blue 0
2 AM Wed 50 50 S 12 4461 6350 0 Blue 0
3 AM Wed 50 50 S 12 4461 6350 0 Blue 0
4 AM Wed 49 49 S 10 4398 6350 0 Blue 0
5 AM Wed 49 49 S 10 4398 6350 0 Blue 0
6 AM Wed 49 49 S 10 4398 6350 0 Blue 0
7 AM Wed 49 49 S 10 4398 6350 0 Blue 0
8 AM Wed 50 50 S 10 4461 6350 0 Blue 0
9 AM Wed 51 51 S 10 4540 6350 0 Blue 1
10 AM Wed 53 54 S 12 5002 6350 0 Blue 4
11 AM Wed 55 56 S 12 5295 6350 0 Blue 6
12 Noon Wed 56 57 S 12 5418 6350 0 Blue 7
1 PM Wed 57 58 S 12 5542 6350 0 Blue 8
2 PM Wed 56 57 S 12 5418 6350 0 Blue 7
3 PM Wed 55 55 S 12 5172 6350 0 Blue 5
4 PM Wed 54 54 SW 10 5002 6350 0 Blue 4
5 PM Wed 53 53 SW 10 4700 6350 0 Blue 3
6 PM Wed 52 52 SW 10 4620 6350 0 Blue 2
7 PM Wed 52 52 SW 10 4620 6350 0 Blue 2
8 PM Wed 52 52 SW 10 4620 6350 0 Blue 2
9 PM Wed 52 52 SW 10 4620 6350 0 Blue 2
10 PM Wed 52 52 SE 10 4620 6350 0 Blue 2
11 PM Wed 51 51 SE 10 4540 6350 0 Blue 1
12 Midnight Thu 52 52 SE 10 4620 6350 0 Blue 2
1 AM Thu 52 52 SE 10 4620 6350 0 Blue 2
2 AM Thu 51 51 SE 10 4540 6350 0 Blue 1
3 AM Thu 51 51 SE 10 4540 6350 0 Blue 1
4 AM Thu 51 51 W 6 4540 6350 0 Blue 1
5 AM Thu 50 50 W 6 4461 6350 0 Blue 0
6 AM Thu 50 50 W 6 4461 6350 0 Blue 0
7 AM Thu 50 50 W 6 4461 6350 0 Blue 0
8 AM Thu 51 51 W 6 4540 6350 0 Blue 1
9 AM Thu 52 52 W 6 4620 6350 0 Blue 2
10 AM Thu 53 53 SW 6 4700 6350 0 Blue 3
11 AM Thu 54 54 SW 6 5002 6350 0 Blue 4
12 Noon Thu 54 54 SW 6 5002 6350 0 Blue 4
1 PM Thu 54 54 SW 6 5002 6350 0 Blue 4
2 PM Thu 54 54 SW 6 5002 6350 0 Blue 4
3 PM Thu 53 53 SW 6 4700 6350 0 Blue 3
4 PM Thu 52 52 W 7 4620 6350 0 Blue 2
5 PM Thu 52 52 W 7 4620 6350 0 Blue 2
6 PM Thu 51 51 W 7 4540 6350 0 Blue 1
7 PM Thu 50 50 W 7 4461 6350 0 Blue 0
8 PM Thu 50 50 W 7 4461 6350 0 Blue 0
9 PM Thu 49 49 W 7 4398 6350 0 Blue 0
10 PM Thu 49 49 W 7 4398 6350 0 Blue 0
11 PM Thu 49 49 W 7 4398 6350 0 Blue 0
12 Midnight Fri 49 49 W 7 4398 6350 0 Blue 0
1 AM Fri 49 49 W 7 4398 6350 0 Blue 0
2 AM Fri 49 49 W 7 4398 6350 0 Blue 0
3 AM Fri 49 49 W 7 4398 6350 0 Blue 0
4 AM Fri 49 49 W 6 4398 6350 0 Blue 0
5 AM Fri 48 48 W 6 4335 6350 0 Blue 0
6 AM Fri 48 48 W 6 4335 6350 0 Blue 0
7 AM Fri 48 48 W 6 4335 6350 0 Blue 0
8 AM Fri 49 49 W 6 4398 6350 0 Blue 0
9 AM Fri 50 50 W 6 4461 6350 0 Blue 0
10 AM Fri 51 51 SW 6 4540 6350 0 Blue 1
11 AM Fri 52 52 SW 6 4620 6350 0 Blue 2
12 Noon Fri 52 52 SW 6 4620 6350 0 Blue 2
1 PM Fri 52 52 SW 6 4620 6350 0 Blue 2
2 PM Fri 51 51 SW 6 4540 6350 0 Blue 1
3 PM Fri 50 50 SW 6 4461 6350 0 Blue 0
4 PM Fri 49 49 SW 7 4398 6350 0 Blue 0
5 PM Fri 48 48 SW 7 4335 6350 0 Blue 0
6 PM Fri 47 47 SW 7 4273 6350 0 Blue 0
7 PM Fri 46 46 SW 7 4210 6350 0 Blue 0
8 PM Fri 46 46 SW 7 4210 6350 0 Blue 0
9 PM Fri 46 46 SW 7 4210 6350 0 Blue 0
10 PM Fri 46 46 SW 7 4210 6350 0 Blue 0
11 PM Fri 46 46 SW 7 4210 6350 0 Blue 0
12 Midnight Sat 46 46 SW 7 4210 6350 0 Blue 0
1 AM Sat 45 45 SW 7 4154 6350 0 Blue 0
2 AM Sat 45 45 SW 7 4154 6350 0 Blue 0
3 AM Sat 45 45 SW 7 4154 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 website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the National Weather Service 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 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