Detailed Predictions for: Dumps
Launch Lat, Long, Altitude (f): 37.67264, -122.49, 200
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 50 30 SW 5 8 0 200 0 Blue 0
1 AM Wed 51 31 SW 4 5 0 200 0 Blue 0
2 AM Wed 51 31 SW 4 6 0 200 0 Blue 0
3 AM Wed 51 31 SW 4 5 0 200 0 Blue 0
4 AM Wed 50 30 SW 4 5 0 200 0 Blue 0
5 AM Wed 51 31 WSW 5 6 0 200 0 Blue 0
6 AM Wed 50 30 SW 9 11 0 200 0 Blue 0
7 AM Wed 51 31 SW 9 11 0 200 0 Blue 0
8 AM Wed 51 31 SW 10 12 0 200 0 Blue 0
9 AM Wed 52 33 SW 11 13 0 200 0 Blue 0
10 AM Wed 52 35 SW 13 16 0 200 0 Blue 0
11 AM Wed 53 37 SW 14 18 0 200 0 Blue 0
12 Noon Wed 54 39 SW 16 19 0 200 0 Blue 0
1 PM Wed 54 39 SW 13 18 0 200 0 Blue 0
2 PM Wed 54 38 SW 12 16 0 200 0 Blue 0
3 PM Wed 53 37 SW 12 16 0 200 0 Blue 0
4 PM Wed 54 36 SW 12 16 0 200 0 Blue 0
5 PM Wed 54 35 SW 12 14 0 200 0 Blue 0
6 PM Wed 53 33 SW 11 14 0 200 0 Blue 0
7 PM Wed 53 33 SW 11 14 0 200 0 Blue 0
8 PM Wed 53 33 SW 11 13 0 200 0 Blue 0
9 PM Wed 52 32 SW 11 13 0 200 0 Blue 0
10 PM Wed 51 31 SW 10 13 0 200 0 Blue 0
11 PM Wed 51 31 SW 10 13 0 200 0 Blue 0
12 Midnight Thu 51 31 SW 10 13 0 200 0 Blue 0
1 AM Thu 50 30 SW 11 13 0 200 0 Blue 0
2 AM Thu 50 30 SW 11 14 0 200 0 Blue 0
3 AM Thu 50 30 SW 12 14 0 200 0 Blue 0
4 AM Thu 50 30 SW 12 14 0 200 0 Blue 0
5 AM Thu 50 30 SW 12 14 0 200 0 Blue 0
6 AM Thu 51 31 SW 12 14 0 200 0 Blue 0
7 AM Thu 51 31 SW 12 16 0 200 0 Blue 0
8 AM Thu 51 31 SW 13 16 0 200 0 Blue 0
9 AM Thu 50 31 SW 13 17 0 200 0 Blue 0
10 AM Thu 51 33 SW 14 18 0 200 0 Blue 0
11 AM Thu 51 34 SW 13 17 0 200 0 Blue 0
12 Noon Thu 51 34 SW 13 17 0 200 0 Blue 0
1 PM Thu 52 35 SW 13 17 0 200 0 Blue 0
2 PM Thu 52 36 SW 12 16 0 200 0 Blue 0
3 PM Thu 53 37 SW 12 16 0 200 0 Blue 0
4 PM Thu 53 35 SW 12 16 0 200 0 Blue 0
5 PM Thu 53 34 WSW 11 14 0 200 0 Blue 0
6 PM Thu 53 33 WSW 11 14 0 200 0 Blue 0
7 PM Thu 53 33 WSW 11 14 0 200 0 Blue 0
8 PM Thu 53 33 WSW 11 14 0 200 0 Blue 0
9 PM Thu 51 31 WSW 11 14 0 200 0 Blue 0
10 PM Thu 50 30 WSW 11 14 0 200 0 Blue 0
11 PM Thu 50 30 SW 12 16 0 200 0 Blue 0
12 Midnight Fri 51 31 SW 12 16 0 200 0 Blue 0
1 AM Fri 52 32 SW 12 16 0 200 0 Blue 0
2 AM Fri 53 33 SW 13 17 0 200 0 Blue 0
3 AM Fri 53 33 SW 13 17 0 200 0 Blue 0
4 AM Fri 52 32 SW 13 17 0 200 0 Blue 0
5 AM Fri 52 32 SW 13 18 0 200 0 Blue 0
6 AM Fri 52 32 SW 13 18 0 200 0 Blue 0
7 AM Fri 52 32 SW 13 18 0 200 0 Blue 0
8 AM Fri 51 31 SW 16 19 0 200 0 Blue 0
9 AM Fri 51 32 SW 16 19 0 200 0 Blue 0
10 AM Fri 50 32 SW 16 19 0 200 0 Blue 0
11 AM Fri 50 32 SW 16 19 0 200 0 Blue 0
12 Noon Fri 50 33 SW 16 19 0 200 0 Blue 0
1 PM Fri 50 33 SW 16 19 0 200 0 Blue 0
2 PM Fri 51 35 WSW 17 20 0 200 0 Blue 0
3 PM Fri 51 34 WSW 17 20 0 200 0 Blue 0
4 PM Fri 52 34 WSW 17 20 0 200 0 Blue 0
5 PM Fri 52 33 WSW 17 21 0 200 0 Blue 0
6 PM Fri 52 32 WSW 17 21 0 200 0 Blue 0
7 PM Fri 52 32 WSW 17 21 0 200 0 Blue 0
8 PM Fri 53 33 WSW 18 23 0 200 0 Blue 0
9 PM Fri 52 32 WSW 18 23 0 200 0 Blue 0
10 PM Fri 53 33 WSW 18 23 0 200 0 Blue 0
11 PM Fri 53 33 SW 16 19 0 200 0 Blue 0
12 Midnight Sat 53 33 SW 16 19 0 200 0 Blue 0
1 AM Sat 53 33 SW 16 19 0 200 0 Blue 0
2 AM Sat 52 32 SW 12 16 0 200 0 Blue 0
3 AM Sat 52 32 SW 12 16 0 200 0 Blue 0
4 AM Sat 52 32 SW 12 16 0 200 0 Blue 0
5 AM Sat 53 33 SSW 13 18 0 200 0 Blue 0
6 AM Sat 53 33 SSW 13 18 0 200 0 Blue 0
7 AM Sat 54 34 SSW 13 18 0 200 0 Blue 0
8 AM Sat 54 34 WSW 6 9 0 200 0 Blue 0
9 AM Sat 54 35 WSW 6 9 0 200 0 Blue 0
10 AM Sat 54 36 WSW 6 9 0 200 0 Blue 0
11 AM Sat 54 37 WSW 9 11 0 200 0 Blue 0
12 Noon Sat 55 39 WSW 9 11 0 200 0 Blue 0
1 PM Sat 55 39 WSW 9 11 0 200 0 Blue 0
2 PM Sat 55 40 WSW 11 14 0 200 0 Blue 0
3 PM Sat 54 38 WSW 11 14 0 200 0 Blue 0
4 PM Sat 54 37 WSW 11 14 0 200 0 Blue 0
5 PM Sat 54 35 WSW 12 16 0 200 0 Blue 0
6 PM Sat 54 34 WSW 12 16 0 200 0 Blue 0
7 PM Sat 55 35 WSW 12 16 0 200 0 Blue 0
8 PM Sat 55 35 WSW 10 13 0 200 0 Blue 0
9 PM Sat 55 35 WSW 10 13 0 200 0 Blue 0
10 PM Sat 54 34 WSW 10 13 0 200 0 Blue 0
11 PM Sat 54 34 SW 10 13 0 200 0 Blue 0
12 Midnight Sun 53 33 SW 10 13 0 200 0 Blue 0
1 AM Sun 52 32 SW 10 13 0 200 0 Blue 0
2 AM Sun 52 32 SW 10 13 0 200 0 Blue 0
3 AM Sun 52 32 SW 10 13 0 200 0 Blue 0
4 AM Sun 52 32 SW 10 13 0 200 0 Blue 0
5 AM Sun 52 32 SSW 9 11 0 200 0 Blue 0
6 AM Sun 52 32 SSW 9 11 0 200 0 Blue 0
7 AM Sun 52 32 SSW 9 11 0 200 0 Blue 0
8 AM Sun 53 33 SSW 9 11 0 200 0 Blue 0
9 AM Sun 54 35 SSW 9 11 0 200 0 Blue 0
10 AM Sun 55 37 SSW 9 11 0 200 0 Blue 0
11 AM Sun 56 39 SSW 11 14 0 200 0 Blue 0
12 Noon Sun 56 40 SSW 11 14 0 200 0 Blue 0
1 PM Sun 55 39 SSW 11 14 0 200 0 Blue 0
2 PM Sun 55 40 SW 14 18 0 200 0 Blue 0
3 PM Sun 55 40 SW 14 18 0 200 0 Blue 0
4 PM Sun 55 38 SW 14 18 0 200 0 Blue 0
5 PM Sun 55 37 SW 17 21 0 200 0 Blue 0
6 PM Sun 55 36 SW 17 21 0 200 0 Blue 0
7 PM Sun 55 35 SW 17 21 0 200 0 Blue 0
8 PM Sun 55 35 SW 13 17 0 200 0 Blue 0
9 PM Sun 54 34 SW 13 17 0 200 0 Blue 0
10 PM Sun 54 34 SW 13 17 0 200 0 Blue 0
11 PM Sun 54 34 SW 11 14 0 200 0 Blue 0
12 Midnight Mon 54 34 SW 11 14 0 200 0 Blue 0
1 AM Mon 54 34 SW 11 14 0 200 0 Blue 0
2 AM Mon 55 35 SW 11 14 0 200 0 Blue 0
3 AM Mon 54 34 SW 11 14 0 200 0 Blue 0
4 AM Mon 54 34 SW 11 14 0 200 0 Blue 0
5 AM Mon 53 33 SW 10 13 0 200 0 Blue 0
6 AM Mon 53 33 SW 10 13 0 200 0 Blue 0
7 AM Mon 53 33 SW 10 13 0 200 0 Blue 0
8 AM Mon 54 34 WSW 9 11 0 200 0 Blue 0
9 AM Mon 52 32 WSW 9 11 0 200 0 Blue 0
10 AM Mon 52 33 WSW 9 11 0 200 0 Blue 0
11 AM Mon 52 34 WSW 11 13 0 200 0 Blue 0
12 Noon Mon 52 34 WSW 11 13 0 200 0 Blue 0
1 PM Mon 52 34 WSW 11 13 0 200 0 Blue 0
2 PM Mon 54 38 W 14 19 0 200 0 Blue 0
3 PM Mon 54 37 W 14 19 0 200 0 Blue 0
4 PM Mon 54 36 W 14 19 0 200 0 Blue 0
5 PM Mon 54 35 W 18 23 0 200 0 Blue 0
6 PM Mon 54 34 W 18 23 0 200 0 Blue 0
7 PM Mon 53 33 W 18 23 0 200 0 Blue 0
8 PM Mon 53 33 W 17 21 0 200 0 Blue 0
9 PM Mon 52 32 W 17 21 0 200 0 Blue 0
10 PM Mon 52 32 W 17 21 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 ac_soaring@yahoo.com