Detailed Predictions for: Marina Beach
Launch Lat, Long, Altitude (f): 36.600, -121.89, 60
LZ Altitude (f): 0
Sounding

Station:

KOAK

Date/Time:

12 MAY 2021

Temp/Wind data from:

NOAA Digital Forecast

Site Forecasts
Time
(Local)
High
Temp

Puddle
Temp

Wind
(mph)
Wind
Gust
Thermal
Ceiling

(ft)
Soaring
Ceiling

(ft)
Above
Launch

(ft)
Thermal
Type
Thermal
Index

(F)
12 Midnight Wed 52 32 W 0 1 0 60 0 Blue 0
1 AM Wed 52 32 W 1 2 0 60 0 Blue 0
2 AM Wed 51 31 SW 2 2 0 60 0 Blue 0
3 AM Wed 51 31 SW 2 2 0 60 0 Blue 0
4 AM Wed 50 30 SW 2 3 0 60 0 Blue 0
5 AM Wed 50 30 SW 2 3 0 60 0 Blue 0
6 AM Wed 51 31 SW 3 3 0 60 0 Blue 0
7 AM Wed 51 31 SW 3 4 0 60 0 Blue 0
8 AM Wed 52 32 SW 2 3 0 60 0 Blue 0
9 AM Wed 55 36 WSW 3 4 0 60 0 Blue 0
10 AM Wed 57 40 WSW 6 8 0 60 0 Blue 0
11 AM Wed 57 42 WSW 9 11 0 60 0 Blue 0
12 Noon Wed 59 45 WSW 10 12 0 60 0 Blue 0
1 PM Wed 58 45 WSW 10 12 0 60 0 Blue 0
2 PM Wed 58 45 WSW 10 12 0 60 0 Blue 0
3 PM Wed 59 44 WSW 9 11 0 60 0 Blue 0
4 PM Wed 60 44 W 9 11 0 60 0 Blue 0
5 PM Wed 59 41 W 6 9 0 60 0 Blue 0
6 PM Wed 58 38 W 5 6 0 60 0 Blue 0
7 PM Wed 56 36 W 3 4 0 60 0 Blue 0
8 PM Wed 53 33 W 2 3 0 60 0 Blue 0
9 PM Wed 53 33 W 1 2 0 60 0 Blue 0
10 PM Wed 52 32 NNW 1 1 0 60 0 Blue 0
11 PM Wed 52 32 NNW 0 0 0 60 0 Blue 0
12 Midnight Thu 52 32 W 1 1 0 60 0 Blue 0
1 AM Thu 51 31 W 1 1 0 60 0 Blue 0
2 AM Thu 51 31 W 1 2 0 60 0 Blue 0
3 AM Thu 51 31 WSW 1 2 0 60 0 Blue 0
4 AM Thu 51 31 SW 1 2 0 60 0 Blue 0
5 AM Thu 50 30 WSW 3 3 0 60 0 Blue 0
6 AM Thu 50 30 WSW 3 3 0 60 0 Blue 0
7 AM Thu 50 30 WSW 2 3 0 60 0 Blue 0
8 AM Thu 53 33 W 2 3 0 60 0 Blue 0
9 AM Thu 54 34 W 3 3 0 60 0 Blue 0
10 AM Thu 56 38 W 4 5 0 60 0 Blue 0
11 AM Thu 56 40 W 8 9 0 60 0 Blue 0
12 Noon Thu 56 41 W 8 9 0 60 0 Blue 0
1 PM Thu 57 42 W 8 9 0 60 0 Blue 0
2 PM Thu 58 44 W 9 11 0 60 0 Blue 0
3 PM Thu 58 43 W 9 11 0 60 0 Blue 0
4 PM Thu 58 41 W 9 11 0 60 0 Blue 0
5 PM Thu 58 40 W 6 8 0 60 0 Blue 0
6 PM Thu 57 37 W 6 8 0 60 0 Blue 0
7 PM Thu 56 36 W 6 8 0 60 0 Blue 0
8 PM Thu 55 35 WNW 3 4 0 60 0 Blue 0
9 PM Thu 54 34 WNW 3 4 0 60 0 Blue 0
10 PM Thu 53 33 WNW 3 4 0 60 0 Blue 0
11 PM Thu 52 32 WNW 3 3 0 60 0 Blue 0
12 Midnight Fri 52 32 WNW 3 3 0 60 0 Blue 0
1 AM Fri 51 31 WNW 3 3 0 60 0 Blue 0
2 AM Fri 51 31 W 3 4 0 60 0 Blue 0
3 AM Fri 50 30 W 3 4 0 60 0 Blue 0
4 AM Fri 50 30 W 3 4 0 60 0 Blue 0
5 AM Fri 50 30 W 4 4 0 60 0 Blue 0
6 AM Fri 51 31 W 4 4 0 60 0 Blue 0
7 AM Fri 52 32 W 4 4 0 60 0 Blue 0
8 AM Fri 52 32 W 5 6 0 60 0 Blue 0
9 AM Fri 53 33 W 5 6 0 60 0 Blue 0
10 AM Fri 53 34 W 5 6 0 60 0 Blue 0
11 AM Fri 54 37 W 10 12 0 60 0 Blue 0
12 Noon Fri 55 38 W 10 12 0 60 0 Blue 0
1 PM Fri 56 40 W 10 12 0 60 0 Blue 0
2 PM Fri 56 41 W 10 13 0 60 0 Blue 0
3 PM Fri 56 40 W 10 13 0 60 0 Blue 0
4 PM Fri 56 39 W 10 13 0 60 0 Blue 0
5 PM Fri 55 36 W 9 11 0 60 0 Blue 0
6 PM Fri 54 34 W 9 11 0 60 0 Blue 0
7 PM Fri 53 33 W 9 11 0 60 0 Blue 0
8 PM Fri 52 32 W 6 9 0 60 0 Blue 0
9 PM Fri 52 32 W 6 9 0 60 0 Blue 0
10 PM Fri 52 32 W 6 9 0 60 0 Blue 0
11 PM Fri 52 32 W 6 8 0 60 0 Blue 0
12 Midnight Sat 52 32 W 6 8 0 60 0 Blue 0
1 AM Sat 52 32 W 6 8 0 60 0 Blue 0
2 AM Sat 52 32 WSW 5 6 0 60 0 Blue 0
3 AM Sat 51 31 WSW 5 6 0 60 0 Blue 0
4 AM Sat 51 31 WSW 5 6 0 60 0 Blue 0
5 AM Sat 51 31 WSW 6 8 0 60 0 Blue 0
6 AM Sat 51 31 WSW 6 8 0 60 0 Blue 0
7 AM Sat 51 31 WSW 6 8 0 60 0 Blue 0
8 AM Sat 52 32 W 5 8 0 60 0 Blue 0
9 AM Sat 53 33 W 5 8 0 60 0 Blue 0
10 AM Sat 53 34 W 5 8 0 60 0 Blue 0
11 AM Sat 54 37 W 6 9 0 60 0 Blue 0
12 Noon Sat 55 39 W 6 9 0 60 0 Blue 0
1 PM Sat 56 40 W 6 9 0 60 0 Blue 0
2 PM Sat 56 42 WSW 10 12 0 60 0 Blue 0
3 PM Sat 57 42 WSW 10 12 0 60 0 Blue 0
4 PM Sat 57 40 WSW 10 12 0 60 0 Blue 0
5 PM Sat 57 39 WSW 10 12 0 60 0 Blue 0
6 PM Sat 56 36 WSW 10 12 0 60 0 Blue 0
7 PM Sat 56 36 WSW 10 12 0 60 0 Blue 0
8 PM Sat 55 35 WSW 8 10 0 60 0 Blue 0
9 PM Sat 54 34 WSW 8 10 0 60 0 Blue 0
10 PM Sat 54 34 WSW 8 10 0 60 0 Blue 0
11 PM Sat 53 33 SW 6 9 0 60 0 Blue 0
12 Midnight Sun 53 33 SW 6 9 0 60 0 Blue 0
1 AM Sun 52 32 SW 6 9 0 60 0 Blue 0
2 AM Sun 52 32 SW 6 8 0 60 0 Blue 0
3 AM Sun 52 32 SW 6 8 0 60 0 Blue 0
4 AM Sun 51 31 SW 6 8 0 60 0 Blue 0
5 AM Sun 51 31 SSW 5 6 0 60 0 Blue 0
6 AM Sun 51 31 SSW 5 6 0 60 0 Blue 0
7 AM Sun 52 32 SSW 5 6 0 60 0 Blue 0
8 AM Sun 52 32 S 6 8 0 60 0 Blue 0
9 AM Sun 54 35 S 6 8 0 60 0 Blue 0
10 AM Sun 56 38 S 6 8 0 60 0 Blue 0
11 AM Sun 57 41 SW 8 10 0 60 0 Blue 0
12 Noon Sun 58 42 SW 8 10 0 60 0 Blue 0
1 PM Sun 58 43 SW 8 10 0 60 0 Blue 0
2 PM Sun 58 44 WSW 11 14 0 60 0 Blue 0
3 PM Sun 59 44 WSW 11 14 0 60 0 Blue 0
4 PM Sun 59 43 WSW 11 14 0 60 0 Blue 0
5 PM Sun 58 40 WSW 11 14 0 60 0 Blue 0
6 PM Sun 58 38 WSW 11 14 0 60 0 Blue 0
7 PM Sun 57 37 WSW 11 14 0 60 0 Blue 0
8 PM Sun 56 36 WSW 9 11 0 60 0 Blue 0
9 PM Sun 56 36 WSW 9 11 0 60 0 Blue 0
10 PM Sun 55 35 WSW 9 11 0 60 0 Blue 0
11 PM Sun 55 35 SW 6 9 0 60 0 Blue 0
12 Midnight Mon 54 34 SW 6 9 0 60 0 Blue 0
1 AM Mon 53 33 SW 6 9 0 60 0 Blue 0
2 AM Mon 53 33 SW 6 8 0 60 0 Blue 0
3 AM Mon 52 32 SW 6 8 0 60 0 Blue 0
4 AM Mon 52 32 SW 6 8 0 60 0 Blue 0
5 AM Mon 52 32 SW 5 6 0 60 0 Blue 0
6 AM Mon 52 32 SW 5 6 0 60 0 Blue 0
7 AM Mon 52 32 SW 5 6 0 60 0 Blue 0
8 AM Mon 53 33 WSW 5 6 0 60 0 Blue 0
9 AM Mon 54 34 WSW 5 6 0 60 0 Blue 0
10 AM Mon 55 36 WSW 5 6 0 60 0 Blue 0
11 AM Mon 56 39 W 8 10 0 60 0 Blue 0
12 Noon Mon 57 41 W 8 10 0 60 0 Blue 0
1 PM Mon 58 42 W 8 10 0 60 0 Blue 0
2 PM Mon 58 43 W 11 14 0 60 0 Blue 0
3 PM Mon 58 42 W 11 14 0 60 0 Blue 0
4 PM Mon 58 41 W 11 14 0 60 0 Blue 0
5 PM Mon 58 40 WNW 13 17 0 60 0 Blue 0
6 PM Mon 57 37 WNW 13 17 0 60 0 Blue 0
7 PM Mon 56 36 WNW 13 17 0 60 0 Blue 0
8 PM Mon 54 34 WNW 12 14 0 60 0 Blue 0
9 PM Mon 53 33 WNW 12 14 0 60 0 Blue 0
10 PM Mon 52 32 WNW 12 14 0 60 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 or WeatherAPI.com website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the National Weather Service or WeatherAPI.com 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 or WeatherAPI.com website.

Wind Gust: This estimate is taken from the National Weather Service or WeatherAPI.com 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