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

Station:

KOAK

Date/Time:

23 FEB 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)
4 AM Fri 40 20 NW 21 177 177 117 Blue 0
5 AM Fri 40 20 NW 21 177 177 117 Blue 0
6 AM Fri 40 20 NW 21 177 177 117 Blue 0
7 AM Fri 39 19 N 13 177 177 117 Blue 0
8 AM Fri 40 20 N 13 177 177 117 Blue 0
9 AM Fri 44 25 N 13 177 177 117 Blue 0
10 AM Fri 49 31 NW 8 177 177 117 Blue 0
11 AM Fri 51 34 NW 8 177 177 117 Blue 0
12 Noon Fri 53 37 NW 8 177 177 117 Blue 0
1 PM Fri 53 37 NW 18 177 177 117 Blue 0
2 PM Fri 53 36 NW 18 177 177 117 Blue 0
3 PM Fri 53 35 NW 18 177 177 117 Blue 0
4 PM Fri 52 33 NW 23 177 177 117 Blue 0
5 PM Fri 49 29 NW 23 177 177 117 Blue 0
6 PM Fri 46 26 NW 23 177 177 117 Blue 0
7 PM Fri 44 24 NW 21 177 177 117 Blue 0
8 PM Fri 43 23 NW 21 177 177 117 Blue 0
9 PM Fri 42 22 NW 21 177 177 117 Blue 0
10 PM Fri 41 21 E 5 177 177 117 Blue 0
11 PM Fri 40 20 E 5 177 177 117 Blue 0
12 Midnight Sat 40 20 E 5 177 177 117 Blue 0
1 AM Sat 40 20 SE 3 177 177 117 Blue 0
2 AM Sat 39 19 SE 3 177 177 117 Blue 0
3 AM Sat 38 18 SE 3 177 177 117 Blue 0
4 AM Sat 38 18 W 2 177 177 117 Blue 0
5 AM Sat 38 18 W 2 177 177 117 Blue 0
6 AM Sat 38 18 W 2 177 177 117 Blue 0
7 AM Sat 37 17 NW 5 177 177 117 Blue 0
8 AM Sat 38 18 NW 5 177 177 117 Blue 0
9 AM Sat 44 25 NW 5 177 177 117 Blue 0
10 AM Sat 49 31 NW 21 177 177 117 Blue 0
11 AM Sat 52 35 NW 21 177 177 117 Blue 0
12 Noon Sat 54 37 NW 21 177 177 117 Blue 0
1 PM Sat 54 37 NW 24 177 177 117 Blue 0
2 PM Sat 54 36 NW 24 177 177 117 Blue 0
3 PM Sat 55 36 NW 24 177 177 117 Blue 0
4 PM Sat 54 34 NW 24 177 177 117 Blue 0
5 PM Sat 51 31 NW 24 177 177 117 Blue 0
6 PM Sat 48 28 NW 24 177 177 117 Blue 0
7 PM Sat 46 26 NW 24 177 177 117 Blue 0
8 PM Sat 45 25 NW 24 177 177 117 Blue 0
9 PM Sat 45 25 NW 24 177 177 117 Blue 0
10 PM Sat 44 24 NW 21 177 177 117 Blue 0
11 PM Sat 43 23 NW 21 177 177 117 Blue 0
12 Midnight Sun 43 23 NW 21 177 177 117 Blue 0
1 AM Sun 42 22 NW 21 177 177 117 Blue 0
2 AM Sun 42 22 NW 21 177 177 117 Blue 0
3 AM Sun 41 21 NW 21 177 177 117 Blue 0
4 AM Sun 41 21 E 9 177 177 117 Blue 0
5 AM Sun 41 21 E 9 177 177 117 Blue 0
6 AM Sun 41 21 E 9 177 177 117 Blue 0
7 AM Sun 40 20 E 9 177 177 117 Blue 0
8 AM Sun 41 21 E 9 177 177 117 Blue 0
9 AM Sun 46 27 E 9 177 177 117 Blue 0
10 AM Sun 50 32 NW 15 177 177 117 Blue 0
11 AM Sun 53 35 NW 15 177 177 117 Blue 0
12 Noon Sun 54 37 NW 15 177 177 117 Blue 0
1 PM Sun 55 38 NW 15 177 177 117 Blue 0
2 PM Sun 55 37 NW 15 177 177 117 Blue 0
3 PM Sun 55 36 NW 15 177 177 117 Blue 0
4 PM Sun 54 34 NW 22 177 177 117 Blue 0
5 PM Sun 52 32 NW 22 177 177 117 Blue 0
6 PM Sun 50 30 NW 22 177 177 117 Blue 0
7 PM Sun 48 28 NW 22 177 177 117 Blue 0
8 PM Sun 48 28 NW 22 177 177 117 Blue 0
9 PM Sun 47 27 NW 22 177 177 117 Blue 0
10 PM Sun 46 26 NW 13 177 177 117 Blue 0
11 PM Sun 46 26 NW 13 177 177 117 Blue 0
12 Midnight Mon 45 25 NW 13 177 177 117 Blue 0
1 AM Mon 45 25 NW 13 177 177 117 Blue 0
2 AM Mon 45 25 NW 13 177 177 117 Blue 0
3 AM Mon 44 24 NW 13 177 177 117 Blue 0
4 AM Mon 44 24 NE 3 177 177 117 Blue 0
5 AM Mon 44 24 NE 3 177 177 117 Blue 0
6 AM Mon 44 24 NE 3 177 177 117 Blue 0
7 AM Mon 43 23 NE 3 177 177 117 Blue 0
8 AM Mon 44 24 NE 3 177 177 117 Blue 0
9 AM Mon 47 27 NE 3 177 177 117 Blue 0
10 AM Mon 50 31 NW 15 177 177 117 Blue 0
11 AM Mon 51 32 NW 15 177 177 117 Blue 0
12 Noon Mon 52 34 NW 15 177 177 117 Blue 0
1 PM Mon 52 34 NW 15 177 177 117 Blue 0
2 PM Mon 52 33 NW 15 177 177 117 Blue 0
3 PM Mon 52 33 NW 15 177 177 117 Blue 0
4 PM Mon 52 32 NW 22 177 177 117 Blue 0
5 PM Mon 49 29 NW 22 177 177 117 Blue 0
6 PM Mon 47 27 NW 22 177 177 117 Blue 0
7 PM Mon 45 25 NW 22 177 177 117 Blue 0
8 PM Mon 44 24 NW 22 177 177 117 Blue 0
9 PM Mon 43 23 NW 22 177 177 117 Blue 0
10 PM Mon 42 22 NW 18 177 177 117 Blue 0
11 PM Mon 42 22 NW 18 177 177 117 Blue 0
12 Midnight Tue 42 22 NW 18 177 177 117 Blue 0
1 AM Tue 41 21 NW 18 177 177 117 Blue 0
2 AM Tue 41 21 NW 18 177 177 117 Blue 0
3 AM Tue 40 20 NW 18 177 177 117 Blue 0
4 AM Tue 40 20 N 12 177 177 117 Blue 0
5 AM Tue 40 20 N 12 177 177 117 Blue 0
6 AM Tue 40 20 N 12 177 177 117 Blue 0
7 AM Tue 39 19 N 12 177 177 117 Blue 0
8 AM Tue 40 20 N 12 177 177 117 Blue 0
9 AM Tue 45 25 N 12 177 177 117 Blue 0
10 AM Tue 50 31 N 9 177 177 117 Blue 0
11 AM Tue 53 34 N 9 177 177 117 Blue 0
12 Noon Tue 55 37 N 9 177 177 117 Blue 0
1 PM Tue 55 37 N 9 177 177 117 Blue 0
2 PM Tue 55 36 N 9 177 177 117 Blue 0
3 PM Tue 55 36 N 9 177 177 117 Blue 0
4 PM Tue 54 34 NW 14 177 177 117 Blue 0
5 PM Tue 52 32 NW 14 177 177 117 Blue 0
6 PM Tue 49 29 NW 14 177 177 117 Blue 0
7 PM Tue 47 27 NW 14 177 177 117 Blue 0
8 PM Tue 46 26 NW 14 177 177 117 Blue 0
9 PM Tue 46 26 NW 14 177 177 117 Blue 0
10 PM Tue 45 25 NW 12 177 177 117 Blue 0
11 PM Tue 44 24 NW 12 177 177 117 Blue 0
12 Midnight Wed 44 24 NW 12 177 177 117 Blue 0
1 AM Wed 44 24 NW 12 177 177 117 Blue 0
2 AM Wed 43 23 NW 12 177 177 117 Blue 0
3 AM Wed 42 22 NW 12 177 177 117 Blue 0
4 AM Wed 42 22 NW 13 177 177 117 Blue 0
5 AM Wed 42 22 NW 13 177 177 117 Blue 0
6 AM Wed 42 22 NW 13 177 177 117 Blue 0
7 AM Wed 41 21 NW 13 177 177 117 Blue 0
8 AM Wed 42 22 NW 13 177 177 117 Blue 0
9 AM Wed 47 28 NW 13 177 177 117 Blue 0
10 AM Wed 52 33 NW 14 177 177 117 Blue 0
11 AM Wed 54 36 NW 14 177 177 117 Blue 0
12 Noon Wed 56 38 NW 14 177 177 117 Blue 0
1 PM Wed 56 38 NW 14 177 177 117 Blue 0
2 PM Wed 56 38 NW 14 177 177 117 Blue 0
3 PM Wed 56 37 NW 14 177 177 117 Blue 0
4 PM Wed 55 35 NW 18 177 177 117 Blue 0
5 PM Wed 53 33 NW 18 177 177 117 Blue 0
6 PM Wed 51 31 NW 18 177 177 117 Blue 0
7 PM Wed 50 30 NW 18 177 177 117 Blue 0
8 PM Wed 49 29 NW 18 177 177 117 Blue 0
9 PM Wed 48 28 NW 18 177 177 117 Blue 0
10 PM Wed 47 27 NW 12 177 177 117 Blue 0
11 PM Wed 46 26 NW 12 177 177 117 Blue 0
12 Midnight Thu 46 26 NW 12 177 177 117 Blue 0
1 AM Thu 46 26 NW 12 177 177 117 Blue 0
2 AM Thu 46 26 NW 12 177 177 117 Blue 0
3 AM Thu 45 25 NW 12 177 177 117 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