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

Station:

KOAK

Date/Time:

23 SEP 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)
5 AM Sat 49 29 W 2 348 348 288 Blue 0
6 AM Sat 49 29 W 2 348 348 288 Blue 0
7 AM Sat 50 30 W 2 348 348 288 Blue 0
8 AM Sat 52 32 NW 3 348 348 288 Blue 0
9 AM Sat 55 36 NW 3 348 348 288 Blue 0
10 AM Sat 58 40 NW 3 348 348 288 Blue 0
11 AM Sat 61 44 W 10 348 348 288 Blue 0
12 Noon Sat 64 49 W 10 348 348 288 Blue 0
1 PM Sat 65 50 W 10 348 348 288 Blue 0
2 PM Sat 66 51 W 14 348 348 288 Blue 0
3 PM Sat 66 50 W 14 348 348 288 Blue 0
4 PM Sat 66 48 W 14 348 348 288 Blue 0
5 PM Sat 65 46 W 14 348 348 288 Blue 0
6 PM Sat 63 43 W 14 348 348 288 Blue 0
7 PM Sat 61 41 W 14 348 348 288 Blue 0
8 PM Sat 58 38 NW 12 348 348 288 Blue 0
9 PM Sat 56 36 NW 12 348 348 288 Blue 0
10 PM Sat 55 35 NW 12 348 348 288 Blue 0
11 PM Sat 54 34 W 6 348 348 288 Blue 0
12 Midnight Sun 53 33 W 6 348 348 288 Blue 0
1 AM Sun 52 32 W 6 348 348 288 Blue 0
2 AM Sun 51 31 W 5 348 348 288 Blue 0
3 AM Sun 50 30 W 5 348 348 288 Blue 0
4 AM Sun 50 30 W 5 348 348 288 Blue 0
5 AM Sun 49 29 W 5 348 348 288 Blue 0
6 AM Sun 49 29 W 5 348 348 288 Blue 0
7 AM Sun 49 29 W 5 348 348 288 Blue 0
8 AM Sun 51 31 NE 5 348 348 288 Blue 0
9 AM Sun 56 37 NE 5 348 348 288 Blue 0
10 AM Sun 61 43 NE 5 348 348 288 Blue 0
11 AM Sun 65 49 NW 8 348 348 288 Blue 0
12 Noon Sun 68 53 NW 8 348 348 288 Blue 0
1 PM Sun 69 54 NW 8 348 348 288 Blue 0
2 PM Sun 70 55 W 10 348 348 288 Blue 0
3 PM Sun 70 54 W 10 348 348 288 Blue 0
4 PM Sun 70 53 W 10 348 348 288 Blue 0
5 PM Sun 68 49 W 12 348 348 288 Blue 0
6 PM Sun 66 46 W 12 348 348 288 Blue 0
7 PM Sun 63 43 W 12 348 348 288 Blue 0
8 PM Sun 61 41 W 12 348 348 288 Blue 0
9 PM Sun 59 39 W 12 348 348 288 Blue 0
10 PM Sun 58 38 W 12 348 348 288 Blue 0
11 PM Sun 58 38 NE 2 348 348 288 Blue 0
12 Midnight Mon 57 37 NE 2 348 348 288 Blue 0
1 AM Mon 56 36 NE 2 348 348 288 Blue 0
2 AM Mon 55 35 NE 2 348 348 288 Blue 0
3 AM Mon 54 34 NE 2 348 348 288 Blue 0
4 AM Mon 54 34 NE 2 348 348 288 Blue 0
5 AM Mon 53 33 NE 3 348 348 288 Blue 0
6 AM Mon 52 32 NE 3 348 348 288 Blue 0
7 AM Mon 53 33 NE 3 348 348 288 Blue 0
8 AM Mon 54 34 NE 3 348 348 288 Blue 0
9 AM Mon 58 39 NE 3 348 348 288 Blue 0
10 AM Mon 63 45 NE 3 348 348 288 Blue 0
11 AM Mon 67 51 W 9 348 348 288 Blue 0
12 Noon Mon 70 55 W 9 348 348 288 Blue 0
1 PM Mon 72 57 W 9 348 348 288 Blue 0
2 PM Mon 72 57 W 9 348 348 288 Blue 0
3 PM Mon 73 57 W 9 348 348 288 Blue 0
4 PM Mon 72 55 W 9 348 348 288 Blue 0
5 PM Mon 71 52 W 12 348 348 288 Blue 0
6 PM Mon 68 48 W 12 348 348 288 Blue 0
7 PM Mon 65 45 W 12 348 348 288 Blue 0
8 PM Mon 63 43 W 12 348 348 288 Blue 0
9 PM Mon 61 41 W 12 348 348 288 Blue 0
10 PM Mon 60 40 W 12 348 348 288 Blue 0
11 PM Mon 60 40 NE 3 348 348 288 Blue 0
12 Midnight Tue 60 40 NE 3 348 348 288 Blue 0
1 AM Tue 60 40 NE 3 348 348 288 Blue 0
2 AM Tue 60 40 NE 3 348 348 288 Blue 0
3 AM Tue 60 40 NE 3 348 348 288 Blue 0
4 AM Tue 59 39 NE 3 348 348 288 Blue 0
5 AM Tue 58 38 NE 5 348 348 288 Blue 0
6 AM Tue 57 37 NE 5 348 348 288 Blue 0
7 AM Tue 56 36 NE 5 348 348 288 Blue 0
8 AM Tue 57 37 NE 5 348 348 288 Blue 0
9 AM Tue 60 41 NE 5 348 348 288 Blue 0
10 AM Tue 66 48 NE 5 348 348 288 Blue 0
11 AM Tue 71 55 NW 3 348 348 288 Blue 0
12 Noon Tue 75 60 NW 3 348 348 288 Blue 0
1 PM Tue 78 64 NW 3 1873 348 288 Blue 2
2 PM Tue 80 65 NW 3 2226 1152 1092 Blue 3
3 PM Tue 79 63 NW 3 1519 348 288 Blue 1
4 PM Tue 77 60 NW 3 348 348 288 Blue 0
5 PM Tue 74 55 W 8 348 348 288 Blue 0
6 PM Tue 71 51 W 8 348 348 288 Blue 0
7 PM Tue 68 48 W 8 348 348 288 Blue 0
8 PM Tue 66 46 W 8 348 348 288 Blue 0
9 PM Tue 64 44 W 8 348 348 288 Blue 0
10 PM Tue 62 42 W 8 348 348 288 Blue 0
11 PM Tue 61 41 E 1 348 348 288 Blue 0
12 Midnight Wed 60 40 E 1 348 348 288 Blue 0
1 AM Wed 59 39 E 1 348 348 288 Blue 0
2 AM Wed 59 39 E 1 348 348 288 Blue 0
3 AM Wed 60 40 E 1 348 348 288 Blue 0
4 AM Wed 60 40 E 1 348 348 288 Blue 0
5 AM Wed 60 40 E 6 348 348 288 Blue 0
6 AM Wed 59 39 E 6 348 348 288 Blue 0
7 AM Wed 58 38 E 6 348 348 288 Blue 0
8 AM Wed 59 39 E 6 348 348 288 Blue 0
9 AM Wed 64 45 E 6 348 348 288 Blue 0
10 AM Wed 70 52 E 6 348 348 288 Blue 0
11 AM Wed 77 60 N 2 348 348 288 Blue 0
12 Noon Wed 81 65 N 2 2226 1152 1092 Blue 3
1 PM Wed 84 69 N 2 4190 2695 2635 Blue 7
2 PM Wed 84 68 N 2 3950 2206 2146 Blue 6
3 PM Wed 83 67 N 2 3486 1857 1797 Blue 5
4 PM Wed 81 63 N 2 1519 348 288 Blue 1
5 PM Wed 78 59 W 8 348 348 288 Blue 0
6 PM Wed 75 55 W 8 348 348 288 Blue 0
7 PM Wed 71 51 W 8 348 348 288 Blue 0
8 PM Wed 68 48 W 8 348 348 288 Blue 0
9 PM Wed 66 46 W 8 348 348 288 Blue 0
10 PM Wed 65 45 W 8 348 348 288 Blue 0
11 PM Wed 64 44 E 2 348 348 288 Blue 0
12 Midnight Thu 62 42 E 2 348 348 288 Blue 0
1 AM Thu 62 42 E 2 348 348 288 Blue 0
2 AM Thu 61 41 E 2 348 348 288 Blue 0
3 AM Thu 61 41 E 2 348 348 288 Blue 0
4 AM Thu 62 42 E 2 348 348 288 Blue 0
5 AM Thu 61 41 E 5 348 348 288 Blue 0
6 AM Thu 60 40 E 5 348 348 288 Blue 0
7 AM Thu 59 39 E 5 348 348 288 Blue 0
8 AM Thu 60 40 E 5 348 348 288 Blue 0
9 AM Thu 66 47 E 5 348 348 288 Blue 0
10 AM Thu 73 55 E 5 348 348 288 Blue 0
11 AM Thu 80 63 N 3 1519 348 288 Blue 1
12 Noon Thu 84 68 N 3 3950 2206 2146 Blue 6
1 PM Thu 85 70 N 3 4440 3401 3341 Blue 8
2 PM Thu 86 70 N 3 4440 3401 3341 Blue 8
3 PM Thu 85 68 N 3 3950 2206 2146 Blue 6
4 PM Thu 83 65 N 3 2226 1152 1092 Blue 3
5 PM Thu 80 61 W 9 348 348 288 Blue 0
6 PM Thu 76 56 W 9 348 348 288 Blue 0
7 PM Thu 71 51 W 9 348 348 288 Blue 0
8 PM Thu 68 48 W 9 348 348 288 Blue 0
9 PM Thu 66 46 W 9 348 348 288 Blue 0
10 PM Thu 66 46 W 9 348 348 288 Blue 0
11 PM Thu 65 45 N 0 348 348 288 Blue 0
12 Midnight Fri 62 42 N 0 348 348 288 Blue 0
1 AM Fri 60 40 N 0 348 348 288 Blue 0
2 AM Fri 58 38 N 0 348 348 288 Blue 0
3 AM Fri 59 39 N 0 348 348 288 Blue 0
4 AM Fri 61 41 N 0 348 348 288 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