Detailed Predictions for: Dumps
Launch Lat, Long, Altitude (f): 37.67264, -122.49, 200
LZ Altitude (f): 0
Sounding

Station:

KOAK

Date/Time:

21 SEP 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 Tue 63 43 ENE 9 11 0 200 0 Blue 0
1 AM Tue 62 42 E 9 11 0 200 0 Blue 0
2 AM Tue 65 45 ENE 10 13 0 200 0 Blue 0
3 AM Tue 66 46 E 11 13 0 200 0 Blue 0
4 AM Tue 65 45 E 12 16 0 200 0 Blue 0
5 AM Tue 66 46 E 13 17 0 200 0 Blue 0
6 AM Tue 67 47 E 12 16 0 200 0 Blue 0
7 AM Tue 67 47 E 12 14 0 200 0 Blue 0
8 AM Tue 67 47 E 11 14 0 200 0 Blue 0
9 AM Tue 69 50 E 11 13 0 200 0 Blue 0
10 AM Tue 74 56 E 9 11 0 200 0 Blue 0
11 AM Tue 75 58 WSW 4 5 0 200 0 Blue 0
12 Noon Tue 76 60 SSW 11 14 0 200 0 Blue 0
1 PM Tue 77 62 SW 12 16 0 200 0 Blue 0
2 PM Tue 76 60 SW 11 14 0 200 0 Blue 0
3 PM Tue 75 58 SW 11 13 0 200 0 Blue 0
4 PM Tue 74 56 SW 11 14 0 200 0 Blue 0
5 PM Tue 74 55 SW 11 14 0 200 0 Blue 0
6 PM Tue 72 52 SW 11 13 0 200 0 Blue 0
7 PM Tue 71 51 SW 9 11 0 200 0 Blue 0
8 PM Tue 62 42 SW 8 9 0 200 0 Blue 0
9 PM Tue 66 46 SW 5 6 0 200 0 Blue 0
10 PM Tue 65 45 SW 6 8 0 200 0 Blue 0
11 PM Tue 64 44 SW 6 9 0 200 0 Blue 0
12 Midnight Wed 63 43 WSW 5 6 0 200 0 Blue 0
1 AM Wed 62 42 W 4 6 0 200 0 Blue 0
2 AM Wed 61 41 W 5 8 0 200 0 Blue 0
3 AM Wed 60 40 SW 8 10 0 200 0 Blue 0
4 AM Wed 59 39 SW 10 13 0 200 0 Blue 0
5 AM Wed 58 38 SW 9 11 0 200 0 Blue 0
6 AM Wed 58 38 SW 9 11 0 200 0 Blue 0
7 AM Wed 57 37 SW 9 11 0 200 0 Blue 0
8 AM Wed 56 36 WSW 8 9 0 200 0 Blue 0
9 AM Wed 55 35 SW 9 11 0 200 0 Blue 0
10 AM Wed 56 36 SW 10 12 0 200 0 Blue 0
11 AM Wed 57 38 W 10 12 0 200 0 Blue 0
12 Noon Wed 57 39 W 10 12 0 200 0 Blue 0
1 PM Wed 58 40 W 10 12 0 200 0 Blue 0
2 PM Wed 58 39 W 11 13 0 200 0 Blue 0
3 PM Wed 58 39 W 11 13 0 200 0 Blue 0
4 PM Wed 58 39 W 11 13 0 200 0 Blue 0
5 PM Wed 57 37 W 10 13 0 200 0 Blue 0
6 PM Wed 57 37 W 10 13 0 200 0 Blue 0
7 PM Wed 57 37 W 10 13 0 200 0 Blue 0
8 PM Wed 56 36 W 8 10 0 200 0 Blue 0
9 PM Wed 56 36 W 8 10 0 200 0 Blue 0
10 PM Wed 55 35 W 8 10 0 200 0 Blue 0
11 PM Wed 54 34 W 6 8 0 200 0 Blue 0
12 Midnight Thu 54 34 W 6 8 0 200 0 Blue 0
1 AM Thu 54 34 W 6 8 0 200 0 Blue 0
2 AM Thu 54 34 W 5 8 0 200 0 Blue 0
3 AM Thu 54 34 W 5 8 0 200 0 Blue 0
4 AM Thu 55 35 W 5 8 0 200 0 Blue 0
5 AM Thu 55 35 W 4 5 0 200 0 Blue 0
6 AM Thu 54 34 W 4 5 0 200 0 Blue 0
7 AM Thu 54 34 W 4 5 0 200 0 Blue 0
8 AM Thu 54 34 W 3 4 0 200 0 Blue 0
9 AM Thu 55 35 W 3 4 0 200 0 Blue 0
10 AM Thu 57 38 W 3 4 0 200 0 Blue 0
11 AM Thu 58 39 W 5 6 0 200 0 Blue 0
12 Noon Thu 59 41 W 5 6 0 200 0 Blue 0
1 PM Thu 60 42 W 5 6 0 200 0 Blue 0
2 PM Thu 60 42 W 6 9 0 200 0 Blue 0
3 PM Thu 60 41 W 6 9 0 200 0 Blue 0
4 PM Thu 60 41 W 6 9 0 200 0 Blue 0
5 PM Thu 60 40 WSW 5 8 0 200 0 Blue 0
6 PM Thu 59 39 WSW 5 8 0 200 0 Blue 0
7 PM Thu 59 39 WSW 5 8 0 200 0 Blue 0
8 PM Thu 58 38 SW 6 8 0 200 0 Blue 0
9 PM Thu 58 38 SW 6 8 0 200 0 Blue 0
10 PM Thu 58 38 SW 6 8 0 200 0 Blue 0
11 PM Thu 57 37 WSW 6 9 0 200 0 Blue 0
12 Midnight Fri 57 37 WSW 6 9 0 200 0 Blue 0
1 AM Fri 57 37 WSW 6 9 0 200 0 Blue 0
2 AM Fri 57 37 SW 6 8 0 200 0 Blue 0
3 AM Fri 56 36 SW 6 8 0 200 0 Blue 0
4 AM Fri 56 36 SW 6 8 0 200 0 Blue 0
5 AM Fri 56 36 SW 6 9 0 200 0 Blue 0
6 AM Fri 56 36 SW 6 9 0 200 0 Blue 0
7 AM Fri 56 36 SW 6 9 0 200 0 Blue 0
8 AM Fri 56 36 SSW 3 4 0 200 0 Blue 0
9 AM Fri 57 37 SSW 3 4 0 200 0 Blue 0
10 AM Fri 58 39 SSW 3 4 0 200 0 Blue 0
11 AM Fri 59 40 SW 5 8 0 200 0 Blue 0
12 Noon Fri 60 42 SW 5 8 0 200 0 Blue 0
1 PM Fri 60 42 SW 5 8 0 200 0 Blue 0
2 PM Fri 61 43 WSW 9 11 0 200 0 Blue 0
3 PM Fri 61 43 WSW 9 11 0 200 0 Blue 0
4 PM Fri 60 41 WSW 9 11 0 200 0 Blue 0
5 PM Fri 60 40 WSW 10 13 0 200 0 Blue 0
6 PM Fri 60 40 WSW 10 13 0 200 0 Blue 0
7 PM Fri 59 39 WSW 10 13 0 200 0 Blue 0
8 PM Fri 59 39 WSW 9 11 0 200 0 Blue 0
9 PM Fri 58 38 WSW 9 11 0 200 0 Blue 0
10 PM Fri 58 38 WSW 9 11 0 200 0 Blue 0
11 PM Fri 57 37 SW 8 10 0 200 0 Blue 0
12 Midnight Sat 57 37 SW 8 10 0 200 0 Blue 0
1 AM Sat 57 37 SW 8 10 0 200 0 Blue 0
2 AM Sat 57 37 SW 6 9 0 200 0 Blue 0
3 AM Sat 57 37 SW 6 9 0 200 0 Blue 0
4 AM Sat 57 37 SW 6 9 0 200 0 Blue 0
5 AM Sat 56 36 SW 6 9 0 200 0 Blue 0
6 AM Sat 56 36 SW 6 9 0 200 0 Blue 0
7 AM Sat 55 35 SW 6 9 0 200 0 Blue 0
8 AM Sat 55 35 SSW 6 8 0 200 0 Blue 0
9 AM Sat 56 36 SSW 6 8 0 200 0 Blue 0
10 AM Sat 56 37 SSW 6 8 0 200 0 Blue 0
11 AM Sat 57 38 SW 8 10 0 200 0 Blue 0
12 Noon Sat 57 38 SW 8 10 0 200 0 Blue 0
1 PM Sat 58 40 SW 8 10 0 200 0 Blue 0
2 PM Sat 58 40 WSW 12 16 0 200 0 Blue 0
3 PM Sat 58 39 WSW 12 16 0 200 0 Blue 0
4 PM Sat 58 39 WSW 12 16 0 200 0 Blue 0
5 PM Sat 58 38 WSW 13 17 0 200 0 Blue 0
6 PM Sat 57 37 WSW 13 17 0 200 0 Blue 0
7 PM Sat 57 37 WSW 13 17 0 200 0 Blue 0
8 PM Sat 57 37 WSW 10 13 0 200 0 Blue 0
9 PM Sat 57 37 WSW 10 13 0 200 0 Blue 0
10 PM Sat 57 37 WSW 10 13 0 200 0 Blue 0
11 PM Sat 57 37 WSW 8 10 0 200 0 Blue 0
12 Midnight Sun 56 36 WSW 8 10 0 200 0 Blue 0
1 AM Sun 56 36 WSW 8 10 0 200 0 Blue 0
2 AM Sun 56 36 W 8 10 0 200 0 Blue 0
3 AM Sun 56 36 W 8 10 0 200 0 Blue 0
4 AM Sun 56 36 W 8 10 0 200 0 Blue 0
5 AM Sun 56 36 W 8 10 0 200 0 Blue 0
6 AM Sun 56 36 W 8 10 0 200 0 Blue 0
7 AM Sun 55 35 W 8 10 0 200 0 Blue 0
8 AM Sun 55 35 WSW 8 10 0 200 0 Blue 0
9 AM Sun 54 34 WSW 8 10 0 200 0 Blue 0
10 AM Sun 54 34 WSW 8 10 0 200 0 Blue 0
11 AM Sun 54 34 WSW 9 11 0 200 0 Blue 0
12 Noon Sun 54 35 WSW 9 11 0 200 0 Blue 0
1 PM Sun 55 36 WSW 9 11 0 200 0 Blue 0
2 PM Sun 55 36 W 12 16 0 200 0 Blue 0
3 PM Sun 56 37 W 12 16 0 200 0 Blue 0
4 PM Sun 56 36 W 12 16 0 200 0 Blue 0
5 PM Sun 56 36 W 13 17 0 200 0 Blue 0
6 PM Sun 55 35 W 13 17 0 200 0 Blue 0
7 PM Sun 55 35 W 13 17 0 200 0 Blue 0
8 PM Sun 55 35 W 11 14 0 200 0 Blue 0
9 PM Sun 55 35 W 11 14 0 200 0 Blue 0
10 PM Sun 55 35 W 11 14 0 200 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 [email protected]