Detailed Predictions for: Mt Vaca
Launch Lat, Long, Altitude (f): 38.400316, -122.106135, 2821
LZ Altitude (f): 2000
Sounding

Station:

KOAK

Date/Time:

30 NOV 2022

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 45 45 SW 5 6 820 2821 0 Blue 0
1 AM Wed 44 44 SSW 5 8 452 2821 0 Blue 0
2 AM Wed 44 44 SSW 6 8 452 2821 0 Blue 0
3 AM Wed 44 44 SW 6 8 452 2821 0 Blue 0
4 AM Wed 43 43 SW 6 8 449 2821 0 Blue 0
5 AM Wed 42 42 SW 6 8 449 2821 0 Blue 0
6 AM Wed 41 41 SW 6 8 449 2821 0 Blue 0
7 AM Wed 41 41 SW 6 9 449 2821 0 Blue 0
8 AM Wed 42 42 SW 8 9 449 2821 0 Blue 0
9 AM Wed 44 44 WSW 8 10 452 2821 0 Blue 0
10 AM Wed 46 47 WSW 6 9 1417 2821 0 Blue 2
11 AM Wed 48 49 SW 8 10 1967 2821 0 Blue 4
12 Noon Wed 50 52 SW 9 11 2449 2821 0 Blue 7
1 PM Wed 50 51 SW 9 12 2306 2821 0 Blue 6
2 PM Wed 52 53 SW 10 13 2601 2821 0 Blue 8
3 PM Wed 51 51 SW 12 16 2306 2821 0 Blue 6
4 PM Wed 50 50 SW 12 16 2164 2821 0 Blue 5
5 PM Wed 49 49 SW 12 16 1967 2821 0 Blue 4
6 PM Wed 48 48 SW 13 17 1693 2821 0 Blue 3
7 PM Wed 49 49 SW 13 17 1967 2821 0 Blue 4
8 PM Wed 50 50 SW 16 19 2164 2821 0 Blue 5
9 PM Wed 50 50 SSW 16 19 2164 2821 0 Blue 5
10 PM Wed 50 50 SSW 17 21 2164 2821 0 Blue 5
11 PM Wed 49 49 SSW 18 23 1967 2821 0 Blue 4
12 Midnight Thu 49 49 S 20 25 1967 2821 0 Blue 4
1 AM Thu 50 50 S 21 27 2164 2821 0 Blue 5
2 AM Thu 49 49 S 20 26 1967 2821 0 Blue 4
3 AM Thu 49 49 S 21 27 1967 2821 0 Blue 4
4 AM Thu 49 49 S 21 27 1967 2821 0 Blue 4
5 AM Thu 48 48 SSW 19 25 1693 2821 0 Blue 3
6 AM Thu 47 47 SSW 16 20 1417 2821 0 Blue 2
7 AM Thu 46 46 S 13 16 1204 2821 0 Blue 1
8 AM Thu 44 44 SSW 11 13 452 2821 0 Blue 0
9 AM Thu 43 43 SW 11 13 449 2821 0 Blue 0
10 AM Thu 43 43 SW 12 16 449 2821 0 Blue 0
11 AM Thu 43 43 SW 12 16 449 2821 0 Blue 0
12 Noon Thu 43 43 SW 12 16 449 2821 0 Blue 0
1 PM Thu 43 43 WSW 12 14 449 2821 0 Blue 0
2 PM Thu 43 43 WSW 12 14 449 2821 0 Blue 0
3 PM Thu 42 42 WSW 12 14 449 2821 0 Blue 0
4 PM Thu 42 42 W 11 13 449 2821 0 Blue 0
5 PM Thu 42 42 W 11 13 449 2821 0 Blue 0
6 PM Thu 43 43 W 11 13 449 2821 0 Blue 0
7 PM Thu 43 43 W 12 16 449 2821 0 Blue 0
8 PM Thu 43 43 W 12 16 449 2821 0 Blue 0
9 PM Thu 43 43 W 12 16 449 2821 0 Blue 0
10 PM Thu 43 43 W 12 16 449 2821 0 Blue 0
11 PM Thu 43 43 W 12 16 449 2821 0 Blue 0
12 Midnight Fri 42 42 W 12 16 449 2821 0 Blue 0
1 AM Fri 42 42 W 9 11 449 2821 0 Blue 0
2 AM Fri 41 41 W 9 11 449 2821 0 Blue 0
3 AM Fri 40 40 W 9 11 449 2821 0 Blue 0
4 AM Fri 40 40 NW 8 10 449 2821 0 Blue 0
5 AM Fri 40 40 NW 8 10 449 2821 0 Blue 0
6 AM Fri 40 40 NW 8 10 449 2821 0 Blue 0
7 AM Fri 40 40 N 6 9 449 2821 0 Blue 0
8 AM Fri 40 40 N 6 9 449 2821 0 Blue 0
9 AM Fri 40 40 N 6 9 449 2821 0 Blue 0
10 AM Fri 40 41 NE 6 9 449 2821 0 Blue 0
11 AM Fri 42 43 NE 6 9 449 2821 0 Blue 0
12 Noon Fri 43 45 NE 6 9 820 2821 0 Blue 0
1 PM Fri 44 45 E 5 6 820 2821 0 Blue 0
2 PM Fri 45 46 E 5 6 1204 2821 0 Blue 1
3 PM Fri 46 46 E 5 6 1204 2821 0 Blue 1
4 PM Fri 45 45 SE 5 6 820 2821 0 Blue 0
5 PM Fri 45 45 SE 5 6 820 2821 0 Blue 0
6 PM Fri 44 44 SE 5 6 452 2821 0 Blue 0
7 PM Fri 43 43 SW 6 9 449 2821 0 Blue 0
8 PM Fri 43 43 SW 6 9 449 2821 0 Blue 0
9 PM Fri 44 44 SW 6 9 452 2821 0 Blue 0
10 PM Fri 44 44 S 8 10 452 2821 0 Blue 0
11 PM Fri 44 44 S 8 10 452 2821 0 Blue 0
12 Midnight Sat 44 44 S 8 10 452 2821 0 Blue 0
1 AM Sat 44 44 SSE 10 12 452 2821 0 Blue 0
2 AM Sat 44 44 SSE 10 12 452 2821 0 Blue 0
3 AM Sat 44 44 SSE 10 12 452 2821 0 Blue 0
4 AM Sat 44 44 SSE 10 12 452 2821 0 Blue 0
5 AM Sat 43 43 SSE 10 12 449 2821 0 Blue 0
6 AM Sat 43 43 SSE 10 12 449 2821 0 Blue 0
7 AM Sat 42 42 SSE 10 12 449 2821 0 Blue 0
8 AM Sat 41 41 SSE 10 12 449 2821 0 Blue 0
9 AM Sat 41 41 SSE 10 12 449 2821 0 Blue 0
10 AM Sat 41 41 SSE 11 14 449 2821 0 Blue 0
11 AM Sat 42 42 SSE 11 14 449 2821 0 Blue 0
12 Noon Sat 43 43 SSE 11 14 449 2821 0 Blue 0
1 PM Sat 44 44 S 12 16 452 2821 0 Blue 0
2 PM Sat 44 44 S 12 16 452 2821 0 Blue 0
3 PM Sat 45 45 S 12 16 820 2821 0 Blue 0
4 PM Sat 45 45 S 10 12 820 2821 0 Blue 0
5 PM Sat 46 46 S 10 12 1204 2821 0 Blue 1
6 PM Sat 48 48 S 10 12 1693 2821 0 Blue 3
7 PM Sat 49 49 S 8 10 1967 2821 0 Blue 4
8 PM Sat 50 50 S 8 10 2164 2821 0 Blue 5
9 PM Sat 50 50 S 8 10 2164 2821 0 Blue 5
10 PM Sat 50 50 SSE 6 8 2164 2821 0 Blue 5
11 PM Sat 50 50 SSE 6 8 2164 2821 0 Blue 5
12 Midnight Sun 50 50 SSE 6 8 2164 2821 0 Blue 5
1 AM Sun 50 50 SSE 5 6 2164 2821 0 Blue 5
2 AM Sun 50 50 SSE 5 6 2164 2821 0 Blue 5
3 AM Sun 50 50 SSE 5 6 2164 2821 0 Blue 5
4 AM Sun 50 50 SSE 4 5 2164 2821 0 Blue 5
5 AM Sun 49 49 SSE 4 5 1967 2821 0 Blue 4
6 AM Sun 48 48 SSE 4 5 1693 2821 0 Blue 3
7 AM Sun 48 48 SSE 4 5 1693 2821 0 Blue 3
8 AM Sun 46 46 SSE 4 5 1204 2821 0 Blue 1
9 AM Sun 45 45 SSE 4 5 820 2821 0 Blue 0
10 AM Sun 45 45 SE 5 6 820 2821 0 Blue 0
11 AM Sun 45 45 SE 5 6 820 2821 0 Blue 0
12 Noon Sun 45 45 SE 5 6 820 2821 0 Blue 0
1 PM Sun 46 46 S 5 6 1204 2821 0 Blue 1
2 PM Sun 45 45 S 5 6 820 2821 0 Blue 0
3 PM Sun 44 44 S 5 6 452 2821 0 Blue 0
4 PM Sun 44 44 NNW 8 9 452 2821 0 Blue 0
5 PM Sun 44 44 NNW 8 9 452 2821 0 Blue 0
6 PM Sun 45 45 NNW 8 9 820 2821 0 Blue 0
7 PM Sun 46 46 NNW 5 8 1204 2821 0 Blue 1
8 PM Sun 46 46 NNW 5 8 1204 2821 0 Blue 1
9 PM Sun 47 47 NNW 5 8 1417 2821 0 Blue 2
10 PM Sun 47 47 N 6 9 1417 2821 0 Blue 2
11 PM Sun 48 48 N 6 9 1693 2821 0 Blue 3
12 Midnight Mon 48 48 N 6 9 1693 2821 0 Blue 3
1 AM Mon 48 48 NNW 6 8 1693 2821 0 Blue 3
2 AM Mon 47 47 NNW 6 8 1417 2821 0 Blue 2
3 AM Mon 45 45 NNW 6 8 820 2821 0 Blue 0
4 AM Mon 44 44 NNW 5 6 452 2821 0 Blue 0
5 AM Mon 42 42 NNW 5 6 449 2821 0 Blue 0
6 AM Mon 41 41 NNW 5 6 449 2821 0 Blue 0
7 AM Mon 40 40 NNW 5 6 449 2821 0 Blue 0
8 AM Mon 41 41 NNW 5 6 449 2821 0 Blue 0
9 AM Mon 42 42 NNW 5 6 449 2821 0 Blue 0
10 AM Mon 44 45 N 5 8 820 2821 0 Blue 0
11 AM Mon 46 47 N 5 8 1417 2821 0 Blue 2
12 Noon Mon 47 49 N 5 8 1967 2821 0 Blue 4
1 PM Mon 48 50 N 4 5 2164 2821 0 Blue 5
2 PM Mon 49 50 N 4 5 2164 2821 0 Blue 5
3 PM Mon 48 48 N 4 5 1693 2821 0 Blue 3
4 PM Mon 47 47 NNW 3 4 1417 2821 0 Blue 2
5 PM Mon 46 46 NNW 3 4 1204 2821 0 Blue 1
6 PM Mon 45 45 NNW 3 4 820 2821 0 Blue 0
7 PM Mon 44 44 WNW 2 3 452 2821 0 Blue 0
8 PM Mon 44 44 WNW 2 3 452 2821 0 Blue 0
9 PM Mon 44 44 WNW 2 3 452 2821 0 Blue 0
10 PM Mon 44 44 NW 3 4 452 2821 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]