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

Station:

KOAK

Date/Time:

6 DEC 2023

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 55 35 NNW 2 4 486 486 286 Blue 0
1 AM Wed 54 34 NNE 1 3 486 486 286 Blue 0
2 AM Wed 52 32 E 1 3 486 486 286 Blue 0
3 AM Wed 52 32 SE 1 2 486 486 286 Blue 0
4 AM Wed 52 32 SSE 1 3 486 486 286 Blue 0
5 AM Wed 52 32 S 3 5 486 486 286 Blue 0
6 AM Wed 53 33 SW 6 7 486 486 286 Blue 0
7 AM Wed 53 33 SSW 4 8 486 486 286 Blue 0
8 AM Wed 54 34 SSW 6 10 486 486 286 Blue 0
9 AM Wed 54 34 SSW 7 12 486 486 286 Blue 0
10 AM Wed 54 34 SSW 9 13 486 486 286 Blue 0
11 AM Wed 55 35 SSW 13 18 486 486 286 Blue 0
12 Noon Wed 54 34 SSW 16 22 486 486 286 Blue 0
1 PM Wed 55 35 SSW 16 22 486 486 286 Blue 0
2 PM Wed 55 35 SSW 19 27 486 486 286 Blue 0
3 PM Wed 55 35 SSW 14 19 486 486 286 Blue 0
4 PM Wed 56 36 SW 15 21 486 486 286 Blue 0
5 PM Wed 57 37 WSW 14 20 486 486 286 Blue 0
6 PM Wed 57 37 W 11 17 486 486 286 Blue 0
7 PM Wed 56 36 WNW 11 16 486 486 286 Blue 0
8 PM Wed 54 34 W 9 13 486 486 286 Blue 0
9 PM Wed 54 34 W 11 16 486 486 286 Blue 0
10 PM Wed 54 34 W 9 14 486 486 286 Blue 0
11 PM Wed 52 32 W 10 15 486 486 286 Blue 0
12 Midnight Thu 54 34 W 9 14 486 486 286 Blue 0
1 AM Thu 54 34 W 8 12 486 486 286 Blue 0
2 AM Thu 51 31 W 8 12 486 486 286 Blue 0
3 AM Thu 53 33 W 8 13 486 486 286 Blue 0
4 AM Thu 53 33 WNW 9 14 486 486 286 Blue 0
5 AM Thu 51 31 WNW 7 11 486 486 286 Blue 0
6 AM Thu 53 33 WNW 7 11 486 486 286 Blue 0
7 AM Thu 53 33 WNW 6 9 486 486 286 Blue 0
8 AM Thu 51 31 WNW 5 8 486 486 286 Blue 0
9 AM Thu 53 33 W 5 8 486 486 286 Blue 0
10 AM Thu 55 35 WSW 7 10 486 486 286 Blue 0
11 AM Thu 53 33 WSW 10 13 486 486 286 Blue 0
12 Noon Thu 56 36 SW 10 13 486 486 286 Blue 0
1 PM Thu 56 36 SW 11 15 486 486 286 Blue 0
2 PM Thu 55 35 WSW 14 19 486 486 286 Blue 0
3 PM Thu 54 34 WSW 15 20 486 486 286 Blue 0
4 PM Thu 55 35 WNW 13 17 486 486 286 Blue 0
5 PM Thu 55 35 WNW 13 17 486 486 286 Blue 0
6 PM Thu 54 34 NW 13 18 486 486 286 Blue 0
7 PM Thu 53 33 NW 13 18 486 486 286 Blue 0
8 PM Thu 52 32 NW 11 16 486 486 286 Blue 0
9 PM Thu 52 32 NW 10 15 486 486 286 Blue 0
10 PM Thu 52 32 WNW 13 18 486 486 286 Blue 0
11 PM Thu 52 32 WNW 13 19 486 486 286 Blue 0
12 Midnight Fri 52 32 NW 13 19 486 486 286 Blue 0
1 AM Fri 51 31 NNW 10 14 486 486 286 Blue 0
2 AM Fri 50 30 N 7 10 486 486 286 Blue 0
3 AM Fri 49 29 NNE 6 8 486 486 286 Blue 0
4 AM Fri 49 29 NNE 6 10 486 486 286 Blue 0
5 AM Fri 47 27 NE 6 9 486 486 286 Blue 0
6 AM Fri 48 28 NNE 6 9 486 486 286 Blue 0
7 AM Fri 48 28 N 8 11 486 486 286 Blue 0
8 AM Fri 45 25 NNE 7 11 486 486 286 Blue 0
9 AM Fri 48 28 NNE 6 9 486 486 286 Blue 0
10 AM Fri 49 30 NNE 7 9 486 486 286 Blue 0
11 AM Fri 45 26 NNE 6 8 486 486 286 Blue 0
12 Noon Fri 51 33 NNE 6 8 486 486 286 Blue 0
1 PM Fri 52 34 NNE 7 8 486 486 286 Blue 0
2 PM Fri 51 32 N 8 9 486 486 286 Blue 0
3 PM Fri 53 33 N 7 8 486 486 286 Blue 0
4 PM Fri 53 33 NNW 5 7 486 486 286 Blue 0
5 PM Fri 54 34 NW 5 7 486 486 286 Blue 0
6 PM Fri 53 33 WNW 5 7 486 486 286 Blue 0
7 PM Fri 53 33 NW 6 9 486 486 286 Blue 0
8 PM Fri 52 32 NNW 7 11 486 486 286 Blue 0
9 PM Fri 52 32 NNW 8 12 486 486 286 Blue 0
10 PM Fri 51 31 N 6 10 486 486 286 Blue 0
11 PM Fri 52 32 NNE 4 7 486 486 286 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]