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

Station:

KOAK

Date/Time:

20 OCT 2019

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)
5 AM Sun 44 44 NW 9 4275 6350 0 Blue 0
6 AM Sun 46 46 NW 9 4275 6350 0 Blue 0
7 AM Sun 44 44 NW 9 4275 6350 0 Blue 0
8 AM Sun 46 46 NW 10 4275 6350 0 Blue 0
9 AM Sun 49 49 NW 10 4275 6350 0 Blue 0
10 AM Sun 50 51 NW 10 4464 6350 0 Blue 0
11 AM Sun 51 53 W 9 5153 6350 0 Blue 2
12 Noon Sun 53 55 W 9 5812 6350 0 Blue 4
1 PM Sun 53 56 W 9 6124 6350 0 Blue 5
2 PM Sun 54 56 W 9 6124 6350 0 Blue 5
3 PM Sun 54 56 W 9 6124 6350 0 Blue 5
4 PM Sun 54 55 W 9 5812 6350 0 Blue 4
5 PM Sun 53 53 NW 8 5153 6350 0 Blue 2
6 PM Sun 52 52 NW 8 4858 6350 0 Blue 1
7 PM Sun 51 51 NW 8 4464 6350 0 Blue 0
8 PM Sun 50 50 NW 9 4275 6350 0 Blue 0
9 PM Sun 50 50 NW 9 4275 6350 0 Blue 0
10 PM Sun 50 50 NW 9 4275 6350 0 Blue 0
11 PM Sun 50 50 NW 9 4275 6350 0 Blue 0
12 Midnight Mon 51 51 NW 9 4464 6350 0 Blue 0
1 AM Mon 50 50 NW 9 4275 6350 0 Blue 0
2 AM Mon 50 50 NW 9 4275 6350 0 Blue 0
3 AM Mon 50 50 NW 9 4275 6350 0 Blue 0
4 AM Mon 49 49 NW 9 4275 6350 0 Blue 0
5 AM Mon 49 49 NW 9 4275 6350 0 Blue 0
6 AM Mon 50 50 NW 9 4275 6350 0 Blue 0
7 AM Mon 49 49 NW 9 4275 6350 0 Blue 0
8 AM Mon 50 50 NW 9 4275 6350 0 Blue 0
9 AM Mon 55 55 NW 9 5812 6350 0 Blue 4
10 AM Mon 57 58 NW 9 6763 6350 0 Blue 7
11 AM Mon 59 61 N 10 7512 6722 372 Blue 10
12 Noon Mon 61 64 N 10 8017 7495 1145 Blue 13
1 PM Mon 62 65 N 10 8215 7662 1312 Blue 14
2 PM Mon 62 65 N 10 8215 7662 1312 Blue 14
3 PM Mon 63 65 N 10 8215 7662 1312 Blue 14
4 PM Mon 63 64 N 10 8017 7495 1145 Blue 13
5 PM Mon 62 62 N 10 7680 7158 808 Blue 11
6 PM Mon 61 61 N 10 7512 6722 372 Blue 10
7 PM Mon 58 58 N 10 6763 6350 0 Blue 7
8 PM Mon 56 56 N 10 6124 6350 0 Blue 5
9 PM Mon 55 55 N 10 5812 6350 0 Blue 4
10 PM Mon 55 55 N 10 5812 6350 0 Blue 4
11 PM Mon 54 54 N 12 5491 6350 0 Blue 3
12 Midnight Tue 54 54 N 12 5491 6350 0 Blue 3
1 AM Tue 54 54 N 12 5491 6350 0 Blue 3
2 AM Tue 53 53 N 12 5153 6350 0 Blue 2
3 AM Tue 53 53 N 12 5153 6350 0 Blue 2
4 AM Tue 53 53 N 12 5153 6350 0 Blue 2
5 AM Tue 52 52 N 12 4858 6350 0 Blue 1
6 AM Tue 52 52 N 12 4858 6350 0 Blue 1
7 AM Tue 52 52 N 12 4858 6350 0 Blue 1
8 AM Tue 53 53 N 12 5153 6350 0 Blue 2
9 AM Tue 56 56 N 12 6124 6350 0 Blue 5
10 AM Tue 59 60 N 12 7343 6414 64 Blue 9
11 AM Tue 62 64 NW 10 8017 7495 1145 Blue 13
12 Noon Tue 64 67 NW 10 8985 7997 1647 Blue 16
1 PM Tue 65 68 NW 10 9362 8167 1817 Blue 17
2 PM Tue 65 68 NW 10 9362 8167 1817 Blue 17
3 PM Tue 65 67 NW 10 8985 7997 1647 Blue 16
4 PM Tue 65 66 NW 10 8603 7830 1480 Blue 15
5 PM Tue 64 64 NW 10 8017 7495 1145 Blue 13
6 PM Tue 62 62 NW 10 7680 7158 808 Blue 11
7 PM Tue 60 60 NW 10 7343 6414 64 Blue 9
8 PM Tue 59 59 NW 10 7174 6350 0 Blue 8
9 PM Tue 58 58 NW 10 6763 6350 0 Blue 7
10 PM Tue 57 57 NW 10 6434 6350 0 Blue 6
11 PM Tue 57 57 NW 13 6434 6350 0 Blue 6
12 Midnight Wed 57 57 NW 13 6434 6350 0 Blue 6
1 AM Wed 56 56 NW 13 6124 6350 0 Blue 5
2 AM Wed 56 56 NW 13 6124 6350 0 Blue 5
3 AM Wed 55 55 NW 13 5812 6350 0 Blue 4
4 AM Wed 55 55 NW 13 5812 6350 0 Blue 4
5 AM Wed 54 54 N 14 5491 6350 0 Blue 3
6 AM Wed 54 54 N 14 5491 6350 0 Blue 3
7 AM Wed 54 54 N 14 5491 6350 0 Blue 3
8 AM Wed 55 55 N 14 5812 6350 0 Blue 4
9 AM Wed 57 57 N 14 6434 6350 0 Blue 6
10 AM Wed 59 60 N 14 7343 6414 64 Blue 9
11 AM Wed 61 63 N 17 7849 7327 977 Blue 12
12 Noon Wed 62 65 N 17 8215 7662 1312 Blue 14
1 PM Wed 63 66 N 17 8603 7830 1480 Blue 15
2 PM Wed 64 67 N 17 8985 7997 1647 Blue 16
3 PM Wed 64 66 N 17 8603 7830 1480 Blue 15
4 PM Wed 64 65 N 17 8215 7662 1312 Blue 14
5 PM Wed 63 63 N 18 7849 7327 977 Blue 12
6 PM Wed 61 61 N 18 7512 6722 372 Blue 10
7 PM Wed 59 59 N 18 7174 6350 0 Blue 8
8 PM Wed 58 58 N 18 6763 6350 0 Blue 7
9 PM Wed 57 57 N 18 6434 6350 0 Blue 6
10 PM Wed 57 57 N 18 6434 6350 0 Blue 6
11 PM Wed 57 57 N 20 6434 6350 0 Blue 6
12 Midnight Thu 56 56 N 20 6124 6350 0 Blue 5
1 AM Thu 55 55 N 20 5812 6350 0 Blue 4
2 AM Thu 54 54 N 20 5491 6350 0 Blue 3
3 AM Thu 53 53 N 20 5153 6350 0 Blue 2
4 AM Thu 53 53 N 20 5153 6350 0 Blue 2
5 AM Thu 52 52 N 15 4858 6350 0 Blue 1
6 AM Thu 51 51 N 15 4464 6350 0 Blue 0
7 AM Thu 51 51 N 15 4464 6350 0 Blue 0
8 AM Thu 52 52 N 15 4858 6350 0 Blue 1
9 AM Thu 53 53 N 15 5153 6350 0 Blue 2
10 AM Thu 56 57 N 15 6434 6350 0 Blue 6
11 AM Thu 58 60 N 14 7343 6414 64 Blue 9
12 Noon Thu 60 63 N 14 7849 7327 977 Blue 12
1 PM Thu 62 65 N 14 8215 7662 1312 Blue 14
2 PM Thu 63 66 N 14 8603 7830 1480 Blue 15
3 PM Thu 63 65 N 14 8215 7662 1312 Blue 14
4 PM Thu 63 64 N 14 8017 7495 1145 Blue 13
5 PM Thu 62 62 N 10 7680 7158 808 Blue 11
6 PM Thu 59 59 N 10 7174 6350 0 Blue 8
7 PM Thu 57 57 N 10 6434 6350 0 Blue 6
8 PM Thu 55 55 N 10 5812 6350 0 Blue 4
9 PM Thu 54 54 N 10 5491 6350 0 Blue 3
10 PM Thu 54 54 N 10 5491 6350 0 Blue 3
11 PM Thu 54 54 N 8 5491 6350 0 Blue 3
12 Midnight Fri 54 54 N 8 5491 6350 0 Blue 3
1 AM Fri 53 53 N 8 5153 6350 0 Blue 2
2 AM Fri 52 52 N 8 4858 6350 0 Blue 1
3 AM Fri 52 52 N 8 4858 6350 0 Blue 1
4 AM Fri 51 51 N 8 4464 6350 0 Blue 0
5 AM Fri 51 51 N 6 4464 6350 0 Blue 0
6 AM Fri 50 50 N 6 4275 6350 0 Blue 0
7 AM Fri 50 50 N 6 4275 6350 0 Blue 0
8 AM Fri 51 51 N 6 4464 6350 0 Blue 0
9 AM Fri 53 53 N 6 5153 6350 0 Blue 2
10 AM Fri 57 58 N 6 6763 6350 0 Blue 7
11 AM Fri 60 62 N 7 7680 7158 808 Blue 11
12 Noon Fri 62 65 N 7 8215 7662 1312 Blue 14
1 PM Fri 63 67 N 7 8985 7997 1647 Blue 16
2 PM Fri 63 66 N 7 8603 7830 1480 Blue 15
3 PM Fri 63 65 N 7 8215 7662 1312 Blue 14
4 PM Fri 62 63 N 7 7849 7327 977 Blue 12
5 PM Fri 61 61 W 8 7512 6722 372 Blue 10
6 PM Fri 59 59 W 8 7174 6350 0 Blue 8
7 PM Fri 56 56 W 8 6124 6350 0 Blue 5
8 PM Fri 54 54 W 8 5491 6350 0 Blue 3
9 PM Fri 53 53 W 8 5153 6350 0 Blue 2
10 PM Fri 52 52 W 8 4858 6350 0 Blue 1
11 PM Fri 52 52 NW 8 4858 6350 0 Blue 1
12 Midnight Sat 52 52 NW 8 4858 6350 0 Blue 1
1 AM Sat 52 52 NW 8 4858 6350 0 Blue 1
2 AM Sat 51 51 NW 8 4464 6350 0 Blue 0
3 AM Sat 50 50 NW 8 4275 6350 0 Blue 0
4 AM Sat 50 50 NW 8 4275 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 [email protected]