Detailed Predictions for: Marina Beach
Launch Altitude (f): 60
LZ Altitude (f): 0
Sounding

Station:

KOAK

Date/Time:

25 AUG 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 60 40 SW 2 420 420 360 Blue 0
6 AM Sun 59 39 SW 2 420 420 360 Blue 0
7 AM Sun 59 39 SW 2 420 420 360 Blue 0
8 AM Sun 61 41 SW 3 420 420 360 Blue 0
9 AM Sun 65 45 SW 3 420 420 360 Blue 0
10 AM Sun 68 49 SW 3 420 420 360 Blue 0
11 AM Sun 70 53 W 7 420 420 360 Blue 0
12 Noon Sun 72 57 W 7 420 420 360 Blue 0
1 PM Sun 73 59 W 7 420 420 360 Blue 0
2 PM Sun 74 60 SW 8 494 420 360 Blue 0
3 PM Sun 74 59 SW 8 420 420 360 Blue 0
4 PM Sun 73 57 SW 8 420 420 360 Blue 0
5 PM Sun 72 54 W 7 420 420 360 Blue 0
6 PM Sun 69 50 W 7 420 420 360 Blue 0
7 PM Sun 67 47 W 7 420 420 360 Blue 0
8 PM Sun 63 43 W 2 420 420 360 Blue 0
9 PM Sun 62 42 W 2 420 420 360 Blue 0
10 PM Sun 63 43 W 2 420 420 360 Blue 0
11 PM Sun 62 42 NE 2 420 420 360 Blue 0
12 Midnight Mon 62 42 NE 2 420 420 360 Blue 0
1 AM Mon 61 41 NE 2 420 420 360 Blue 0
2 AM Mon 61 41 N 2 420 420 360 Blue 0
3 AM Mon 60 40 N 2 420 420 360 Blue 0
4 AM Mon 60 40 N 2 420 420 360 Blue 0
5 AM Mon 60 40 NW 2 420 420 360 Blue 0
6 AM Mon 60 40 NW 2 420 420 360 Blue 0
7 AM Mon 60 40 NW 2 420 420 360 Blue 0
8 AM Mon 63 43 NW 2 420 420 360 Blue 0
9 AM Mon 66 46 NW 2 420 420 360 Blue 0
10 AM Mon 68 49 NW 2 420 420 360 Blue 0
11 AM Mon 72 55 W 6 420 420 360 Blue 0
12 Noon Mon 74 58 W 6 420 420 360 Blue 0
1 PM Mon 74 58 W 6 420 420 360 Blue 0
2 PM Mon 74 57 W 8 420 420 360 Blue 0
3 PM Mon 74 57 W 8 420 420 360 Blue 0
4 PM Mon 74 56 W 8 420 420 360 Blue 0
5 PM Mon 72 53 W 5 420 420 360 Blue 0
6 PM Mon 70 50 W 5 420 420 360 Blue 0
7 PM Mon 66 46 W 5 420 420 360 Blue 0
8 PM Mon 64 44 NW 2 420 420 360 Blue 0
9 PM Mon 62 42 NW 2 420 420 360 Blue 0
10 PM Mon 62 42 NW 2 420 420 360 Blue 0
11 PM Mon 62 42 N 3 420 420 360 Blue 0
12 Midnight Tue 61 41 N 3 420 420 360 Blue 0
1 AM Tue 61 41 N 3 420 420 360 Blue 0
2 AM Tue 61 41 N 2 420 420 360 Blue 0
3 AM Tue 60 40 N 2 420 420 360 Blue 0
4 AM Tue 60 40 N 2 420 420 360 Blue 0
5 AM Tue 60 40 NW 2 420 420 360 Blue 0
6 AM Tue 61 41 NW 2 420 420 360 Blue 0
7 AM Tue 62 42 NW 2 420 420 360 Blue 0
8 AM Tue 64 44 NW 2 420 420 360 Blue 0
9 AM Tue 67 48 NW 2 420 420 360 Blue 0
10 AM Tue 69 51 NW 2 420 420 360 Blue 0
11 AM Tue 72 56 W 6 420 420 360 Blue 0
12 Noon Tue 73 58 W 6 420 420 360 Blue 0
1 PM Tue 74 59 W 6 420 420 360 Blue 0
2 PM Tue 74 58 W 7 420 420 360 Blue 0
3 PM Tue 74 58 W 7 420 420 360 Blue 0
4 PM Tue 73 56 W 7 420 420 360 Blue 0
5 PM Tue 72 54 W 6 420 420 360 Blue 0
6 PM Tue 69 49 W 6 420 420 360 Blue 0
7 PM Tue 67 47 W 6 420 420 360 Blue 0
8 PM Tue 64 44 NW 2 420 420 360 Blue 0
9 PM Tue 63 43 NW 2 420 420 360 Blue 0
10 PM Tue 63 43 NW 2 420 420 360 Blue 0
11 PM Tue 63 43 W 2 420 420 360 Blue 0
12 Midnight Wed 63 43 W 2 420 420 360 Blue 0
1 AM Wed 63 43 W 2 420 420 360 Blue 0
2 AM Wed 62 42 W 3 420 420 360 Blue 0
3 AM Wed 62 42 W 3 420 420 360 Blue 0
4 AM Wed 61 41 W 3 420 420 360 Blue 0
5 AM Wed 61 41 W 3 420 420 360 Blue 0
6 AM Wed 61 41 W 3 420 420 360 Blue 0
7 AM Wed 62 42 W 3 420 420 360 Blue 0
8 AM Wed 64 44 W 7 420 420 360 Blue 0
9 AM Wed 66 46 W 7 420 420 360 Blue 0
10 AM Wed 68 48 W 7 420 420 360 Blue 0
11 AM Wed 70 55 SW 9 420 420 360 Blue 0
12 Noon Wed 71 58 SW 9 420 420 360 Blue 0
1 PM Wed 72 59 SW 9 420 420 360 Blue 0
2 PM Wed 72 59 W 13 420 420 360 Blue 0
3 PM Wed 73 59 W 13 420 420 360 Blue 0
4 PM Wed 72 56 W 13 420 420 360 Blue 0
5 PM Wed 71 53 W 12 420 420 360 Blue 0
6 PM Wed 68 49 W 12 420 420 360 Blue 0
7 PM Wed 65 45 W 12 420 420 360 Blue 0
8 PM Wed 62 42 W 7 420 420 360 Blue 0
9 PM Wed 61 41 W 7 420 420 360 Blue 0
10 PM Wed 61 41 W 7 420 420 360 Blue 0
11 PM Wed 62 42 W 5 420 420 360 Blue 0
12 Midnight Thu 62 42 W 5 420 420 360 Blue 0
1 AM Thu 62 42 W 5 420 420 360 Blue 0
2 AM Thu 62 42 W 6 420 420 360 Blue 0
3 AM Thu 61 41 W 6 420 420 360 Blue 0
4 AM Thu 61 41 W 6 420 420 360 Blue 0
5 AM Thu 61 41 NW 7 420 420 360 Blue 0
6 AM Thu 61 41 NW 7 420 420 360 Blue 0
7 AM Thu 62 42 NW 7 420 420 360 Blue 0
8 AM Thu 63 43 NW 8 420 420 360 Blue 0
9 AM Thu 65 45 NW 8 420 420 360 Blue 0
10 AM Thu 67 47 NW 8 420 420 360 Blue 0
11 AM Thu 69 54 NW 10 420 420 360 Blue 0
12 Noon Thu 70 57 NW 10 420 420 360 Blue 0
1 PM Thu 71 58 NW 10 420 420 360 Blue 0
2 PM Thu 72 59 W 16 420 420 360 Blue 0
3 PM Thu 72 58 W 16 420 420 360 Blue 0
4 PM Thu 72 56 W 16 420 420 360 Blue 0
5 PM Thu 70 52 W 14 420 420 360 Blue 0
6 PM Thu 68 48 W 14 420 420 360 Blue 0
7 PM Thu 66 46 W 14 420 420 360 Blue 0
8 PM Thu 64 44 NW 12 420 420 360 Blue 0
9 PM Thu 62 42 NW 12 420 420 360 Blue 0
10 PM Thu 62 42 NW 12 420 420 360 Blue 0
11 PM Thu 62 42 NW 8 420 420 360 Blue 0
12 Midnight Fri 62 42 NW 8 420 420 360 Blue 0
1 AM Fri 62 42 NW 8 420 420 360 Blue 0
2 AM Fri 62 42 NW 9 420 420 360 Blue 0
3 AM Fri 61 41 NW 9 420 420 360 Blue 0
4 AM Fri 61 41 NW 9 420 420 360 Blue 0
5 AM Fri 60 40 NW 8 420 420 360 Blue 0
6 AM Fri 61 41 NW 8 420 420 360 Blue 0
7 AM Fri 61 41 NW 8 420 420 360 Blue 0
8 AM Fri 63 43 N 9 420 420 360 Blue 0
9 AM Fri 65 45 N 9 420 420 360 Blue 0
10 AM Fri 67 47 N 9 420 420 360 Blue 0
11 AM Fri 69 54 NW 12 420 420 360 Blue 0
12 Noon Fri 70 57 NW 12 420 420 360 Blue 0
1 PM Fri 71 58 NW 12 420 420 360 Blue 0
2 PM Fri 71 58 NW 17 420 420 360 Blue 0
3 PM Fri 72 58 NW 17 420 420 360 Blue 0
4 PM Fri 72 56 NW 17 420 420 360 Blue 0
5 PM Fri 70 52 NW 15 420 420 360 Blue 0
6 PM Fri 68 49 NW 15 420 420 360 Blue 0
7 PM Fri 65 45 NW 15 420 420 360 Blue 0
8 PM Fri 62 42 NW 13 420 420 360 Blue 0
9 PM Fri 61 41 NW 13 420 420 360 Blue 0
10 PM Fri 61 41 NW 13 420 420 360 Blue 0
11 PM Fri 61 41 NW 9 420 420 360 Blue 0
12 Midnight Sat 61 41 NW 9 420 420 360 Blue 0
1 AM Sat 60 40 NW 9 420 420 360 Blue 0
2 AM Sat 60 40 NW 9 420 420 360 Blue 0
3 AM Sat 59 39 NW 9 420 420 360 Blue 0
4 AM Sat 59 39 NW 9 420 420 360 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