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

Station:

KOAK

Date/Time:

19 AUG 2018

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 53 33 NW 3 427 427 367 Blue 0
6 AM Sun 53 33 NW 3 427 427 367 Blue 0
7 AM Sun 52 32 NW 3 427 427 367 Blue 0
8 AM Sun 53 33 NW 5 427 427 367 Blue 0
9 AM Sun 55 35 NW 5 427 427 367 Blue 0
10 AM Sun 57 37 NW 5 427 427 367 Blue 0
11 AM Sun 59 43 W 9 427 427 367 Blue 0
12 Noon Sun 61 46 W 9 427 427 367 Blue 0
1 PM Sun 62 47 W 9 427 427 367 Blue 0
2 PM Sun 64 49 W 10 427 427 367 Blue 0
3 PM Sun 64 48 W 10 427 427 367 Blue 0
4 PM Sun 65 48 W 10 427 427 367 Blue 0
5 PM Sun 65 46 W 9 427 427 367 Blue 0
6 PM Sun 64 44 W 9 427 427 367 Blue 0
7 PM Sun 62 42 W 9 427 427 367 Blue 0
8 PM Sun 60 40 W 6 427 427 367 Blue 0
9 PM Sun 59 39 W 6 427 427 367 Blue 0
10 PM Sun 58 38 W 6 427 427 367 Blue 0
11 PM Sun 57 37 W 6 427 427 367 Blue 0
12 Midnight Mon 56 36 W 6 427 427 367 Blue 0
1 AM Mon 56 36 W 6 427 427 367 Blue 0
2 AM Mon 55 35 NW 7 427 427 367 Blue 0
3 AM Mon 55 35 NW 7 427 427 367 Blue 0
4 AM Mon 54 34 NW 7 427 427 367 Blue 0
5 AM Mon 54 34 W 3 427 427 367 Blue 0
6 AM Mon 53 33 W 3 427 427 367 Blue 0
7 AM Mon 53 33 W 3 427 427 367 Blue 0
8 AM Mon 53 33 W 8 427 427 367 Blue 0
9 AM Mon 55 35 W 8 427 427 367 Blue 0
10 AM Mon 57 37 W 8 427 427 367 Blue 0
11 AM Mon 58 40 W 12 427 427 367 Blue 0
12 Noon Mon 60 43 W 12 427 427 367 Blue 0
1 PM Mon 61 45 W 12 427 427 367 Blue 0
2 PM Mon 62 45 W 13 427 427 367 Blue 0
3 PM Mon 62 45 W 13 427 427 367 Blue 0
4 PM Mon 62 44 W 13 427 427 367 Blue 0
5 PM Mon 63 44 W 10 427 427 367 Blue 0
6 PM Mon 62 42 W 10 427 427 367 Blue 0
7 PM Mon 61 41 W 10 427 427 367 Blue 0
8 PM Mon 59 39 W 10 427 427 367 Blue 0
9 PM Mon 58 38 W 10 427 427 367 Blue 0
10 PM Mon 58 38 W 10 427 427 367 Blue 0
11 PM Mon 57 37 W 6 427 427 367 Blue 0
12 Midnight Tue 57 37 W 6 427 427 367 Blue 0
1 AM Tue 56 36 W 6 427 427 367 Blue 0
2 AM Tue 56 36 W 6 427 427 367 Blue 0
3 AM Tue 56 36 W 6 427 427 367 Blue 0
4 AM Tue 55 35 W 6 427 427 367 Blue 0
5 AM Tue 55 35 W 5 427 427 367 Blue 0
6 AM Tue 55 35 W 5 427 427 367 Blue 0
7 AM Tue 54 34 W 5 427 427 367 Blue 0
8 AM Tue 55 35 W 5 427 427 367 Blue 0
9 AM Tue 56 36 W 5 427 427 367 Blue 0
10 AM Tue 58 38 W 5 427 427 367 Blue 0
11 AM Tue 59 42 SW 13 427 427 367 Blue 0
12 Noon Tue 61 45 SW 13 427 427 367 Blue 0
1 PM Tue 62 46 SW 13 427 427 367 Blue 0
2 PM Tue 63 47 SW 13 427 427 367 Blue 0
3 PM Tue 63 47 SW 13 427 427 367 Blue 0
4 PM Tue 64 46 SW 13 427 427 367 Blue 0
5 PM Tue 64 45 W 10 427 427 367 Blue 0
6 PM Tue 63 43 W 10 427 427 367 Blue 0
7 PM Tue 61 41 W 10 427 427 367 Blue 0
8 PM Tue 60 40 W 10 427 427 367 Blue 0
9 PM Tue 58 38 W 10 427 427 367 Blue 0
10 PM Tue 58 38 W 10 427 427 367 Blue 0
11 PM Tue 57 37 N 3 427 427 367 Blue 0
12 Midnight Wed 56 36 N 3 427 427 367 Blue 0
1 AM Wed 56 36 N 3 427 427 367 Blue 0
2 AM Wed 55 35 N 3 427 427 367 Blue 0
3 AM Wed 55 35 N 3 427 427 367 Blue 0
4 AM Wed 55 35 N 3 427 427 367 Blue 0
5 AM Wed 54 34 N 2 427 427 367 Blue 0
6 AM Wed 54 34 N 2 427 427 367 Blue 0
7 AM Wed 54 34 N 2 427 427 367 Blue 0
8 AM Wed 54 34 N 2 427 427 367 Blue 0
9 AM Wed 56 36 N 2 427 427 367 Blue 0
10 AM Wed 57 37 N 2 427 427 367 Blue 0
11 AM Wed 59 42 W 9 427 427 367 Blue 0
12 Noon Wed 60 44 W 9 427 427 367 Blue 0
1 PM Wed 62 47 W 9 427 427 367 Blue 0
2 PM Wed 63 48 W 9 427 427 367 Blue 0
3 PM Wed 63 47 W 9 427 427 367 Blue 0
4 PM Wed 64 47 W 9 427 427 367 Blue 0
5 PM Wed 64 46 W 8 427 427 367 Blue 0
6 PM Wed 63 43 W 8 427 427 367 Blue 0
7 PM Wed 61 41 W 8 427 427 367 Blue 0
8 PM Wed 60 40 W 8 427 427 367 Blue 0
9 PM Wed 58 38 W 8 427 427 367 Blue 0
10 PM Wed 58 38 W 8 427 427 367 Blue 0
11 PM Wed 57 37 NW 3 427 427 367 Blue 0
12 Midnight Thu 56 36 NW 3 427 427 367 Blue 0
1 AM Thu 56 36 NW 3 427 427 367 Blue 0
2 AM Thu 56 36 NW 3 427 427 367 Blue 0
3 AM Thu 55 35 NW 3 427 427 367 Blue 0
4 AM Thu 55 35 NW 3 427 427 367 Blue 0
5 AM Thu 55 35 NW 2 427 427 367 Blue 0
6 AM Thu 54 34 NW 2 427 427 367 Blue 0
7 AM Thu 54 34 NW 2 427 427 367 Blue 0
8 AM Thu 54 34 NW 2 427 427 367 Blue 0
9 AM Thu 56 36 NW 2 427 427 367 Blue 0
10 AM Thu 58 38 NW 2 427 427 367 Blue 0
11 AM Thu 59 43 W 10 427 427 367 Blue 0
12 Noon Thu 61 47 W 10 427 427 367 Blue 0
1 PM Thu 62 48 W 10 427 427 367 Blue 0
2 PM Thu 63 49 W 10 427 427 367 Blue 0
3 PM Thu 63 48 W 10 427 427 367 Blue 0
4 PM Thu 64 48 W 10 427 427 367 Blue 0
5 PM Thu 64 46 W 8 427 427 367 Blue 0
6 PM Thu 63 44 W 8 427 427 367 Blue 0
7 PM Thu 61 41 W 8 427 427 367 Blue 0
8 PM Thu 60 40 W 8 427 427 367 Blue 0
9 PM Thu 58 38 W 8 427 427 367 Blue 0
10 PM Thu 58 38 W 8 427 427 367 Blue 0
11 PM Thu 57 37 W 5 427 427 367 Blue 0
12 Midnight Fri 56 36 W 5 427 427 367 Blue 0
1 AM Fri 56 36 W 5 427 427 367 Blue 0
2 AM Fri 55 35 W 5 427 427 367 Blue 0
3 AM Fri 54 34 W 5 427 427 367 Blue 0
4 AM Fri 54 34 W 5 427 427 367 Blue 0
5 AM Fri 54 34 NW 3 427 427 367 Blue 0
6 AM Fri 53 33 NW 3 427 427 367 Blue 0
7 AM Fri 53 33 NW 3 427 427 367 Blue 0
8 AM Fri 53 33 NW 3 427 427 367 Blue 0
9 AM Fri 55 35 NW 3 427 427 367 Blue 0
10 AM Fri 57 37 NW 3 427 427 367 Blue 0
11 AM Fri 58 42 W 9 427 427 367 Blue 0
12 Noon Fri 60 45 W 9 427 427 367 Blue 0
1 PM Fri 61 47 W 9 427 427 367 Blue 0
2 PM Fri 62 48 W 9 427 427 367 Blue 0
3 PM Fri 62 47 W 9 427 427 367 Blue 0
4 PM Fri 63 47 W 9 427 427 367 Blue 0
5 PM Fri 63 45 W 10 427 427 367 Blue 0
6 PM Fri 62 43 W 10 427 427 367 Blue 0
7 PM Fri 61 41 W 10 427 427 367 Blue 0
8 PM Fri 59 39 W 10 427 427 367 Blue 0
9 PM Fri 58 38 W 10 427 427 367 Blue 0
10 PM Fri 57 37 W 10 427 427 367 Blue 0
11 PM Fri 56 36 W 6 427 427 367 Blue 0
12 Midnight Sat 55 35 W 6 427 427 367 Blue 0
1 AM Sat 55 35 W 6 427 427 367 Blue 0
2 AM Sat 54 34 W 6 427 427 367 Blue 0
3 AM Sat 54 34 W 6 427 427 367 Blue 0
4 AM Sat 54 34 W 6 427 427 367 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