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

Station:

KOAK

Date/Time:

N/A

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 Mon 88 88 N 4 10 N/A N/A N/A N/A N/A
1 AM Mon 88 88 N 5 10 N/A N/A N/A N/A N/A
2 AM Mon 88 88 N 5 12 N/A N/A N/A N/A N/A
3 AM Mon 88 88 N 6 13 N/A N/A N/A N/A N/A
4 AM Mon 88 88 N 6 14 N/A N/A N/A N/A N/A
5 AM Mon 86 86 N 8 14 N/A N/A N/A N/A N/A
6 AM Mon 88 88 N 8 14 N/A N/A N/A N/A N/A
7 AM Mon 86 86 N 6 13 N/A N/A N/A N/A N/A
8 AM Mon 85 85 N 6 12 N/A N/A N/A N/A N/A
9 AM Mon 85 85 N 5 11 N/A N/A N/A N/A N/A
10 AM Mon 85 86 N 5 11 N/A N/A N/A N/A N/A
11 AM Mon 86 88 N 5 11 N/A N/A N/A N/A N/A
12 Noon Mon 88 91 N 4 10 N/A N/A N/A N/A N/A
1 PM Mon 88 92 N 4 10 N/A N/A N/A N/A N/A
2 PM Mon 89 92 NNW 4 10 N/A N/A N/A N/A N/A
3 PM Mon 88 91 W 4 11 N/A N/A N/A N/A N/A
4 PM Mon 88 90 W 4 11 N/A N/A N/A N/A N/A
5 PM Mon 86 86 W 4 11 N/A N/A N/A N/A N/A
6 PM Mon 83 83 W 3 9 N/A N/A N/A N/A N/A
7 PM Mon 81 81 WNW 3 9 N/A N/A N/A N/A N/A
8 PM Mon 81 81 NW 3 10 N/A N/A N/A N/A N/A
9 PM Mon 82 82 NW 4 10 N/A N/A N/A N/A N/A
10 PM Mon 83 83 NW 5 11 N/A N/A N/A N/A N/A
11 PM Mon 83 83 NNW 5 13 N/A N/A N/A N/A N/A
12 Midnight Tue 84 84 NW 5 13 N/A N/A N/A N/A N/A
1 AM Tue 84 84 NW 5 13 N/A N/A N/A N/A N/A
2 AM Tue 82 82 NNW 5 12 N/A N/A N/A N/A N/A
3 AM Tue 81 81 NW 5 12 N/A N/A N/A N/A N/A
4 AM Tue 80 80 NNW 5 11 N/A N/A N/A N/A N/A
5 AM Tue 78 78 NNW 5 11 N/A N/A N/A N/A N/A
6 AM Tue 79 79 NW 5 10 N/A N/A N/A N/A N/A
7 AM Tue 78 78 NW 4 9 N/A N/A N/A N/A N/A
8 AM Tue 76 76 WNW 4 8 N/A N/A N/A N/A N/A
9 AM Tue 78 78 W 4 8 N/A N/A N/A N/A N/A
10 AM Tue 79 81 W 3 6 N/A N/A N/A N/A N/A
11 AM Tue 80 83 WSW 3 8 N/A N/A N/A N/A N/A
12 Noon Tue 82 86 WSW 4 8 N/A N/A N/A N/A N/A
1 PM Tue 82 86 WSW 4 10 N/A N/A N/A N/A N/A
2 PM Tue 83 87 SW 5 11 N/A N/A N/A N/A N/A
3 PM Tue 82 85 SW 5 12 N/A N/A N/A N/A N/A
4 PM Tue 81 83 WSW 5 13 N/A N/A N/A N/A N/A
5 PM Tue 79 80 WSW 5 13 N/A N/A N/A N/A N/A
6 PM Tue 77 77 WSW 5 12 N/A N/A N/A N/A N/A
7 PM Tue 74 74 WSW 4 11 N/A N/A N/A N/A N/A
8 PM Tue 72 72 WSW 4 10 N/A N/A N/A N/A N/A
9 PM Tue 72 72 WSW 4 9 N/A N/A N/A N/A N/A
10 PM Tue 72 72 WSW 4 9 N/A N/A N/A N/A N/A
11 PM Tue 72 72 WSW 4 10 N/A N/A N/A N/A N/A
12 Midnight Wed 72 72 WSW 4 9 N/A N/A N/A N/A N/A
1 AM Wed 72 72 WSW 4 9 N/A N/A N/A N/A N/A
2 AM Wed 71 71 WSW 4 9 N/A N/A N/A N/A N/A
3 AM Wed 70 70 WSW 4 9 N/A N/A N/A N/A N/A
4 AM Wed 68 68 W 3 9 N/A N/A N/A N/A N/A
5 AM Wed 67 67 W 3 9 N/A N/A N/A N/A N/A
6 AM Wed 67 67 W 3 9 N/A N/A N/A N/A N/A
7 AM Wed 67 67 W 3 8 N/A N/A N/A N/A N/A
8 AM Wed 67 67 W 3 8 N/A N/A N/A N/A N/A
9 AM Wed 68 68 WSW 3 6 N/A N/A N/A N/A N/A
10 AM Wed 68 69 WSW 3 6 N/A N/A N/A N/A N/A
11 AM Wed 70 72 SW 3 8 N/A N/A N/A N/A N/A
12 Noon Wed 71 74 SW 3 8 N/A N/A N/A N/A N/A
1 PM Wed 73 76 SW 3 9 N/A N/A N/A N/A N/A
2 PM Wed 74 77 SSW 3 9 N/A N/A N/A N/A N/A
3 PM Wed 74 76 SSW 4 10 N/A N/A N/A N/A N/A
4 PM Wed 74 75 SW 4 11 N/A N/A N/A N/A N/A
5 PM Wed 74 74 SW 4 11 N/A N/A N/A N/A N/A
6 PM Wed 72 72 SW 3 10 N/A N/A N/A N/A N/A
7 PM Wed 71 71 WSW 2 9 N/A N/A N/A N/A N/A
8 PM Wed 70 70 WSW 2 8 N/A N/A N/A N/A N/A
9 PM Wed 71 71 WSW 2 6 N/A N/A N/A N/A N/A
10 PM Wed 72 72 WSW 2 6 N/A N/A N/A N/A N/A
11 PM Wed 73 73 WSW 2 6 N/A N/A N/A N/A N/A
12 Midnight Thu 74 74 WSW 1 5 N/A N/A N/A N/A N/A
1 AM Thu 74 74 WSW 1 5 N/A N/A N/A N/A N/A
2 AM Thu 73 73 WSW 1 5 N/A N/A N/A N/A N/A
3 AM Thu 72 72 WSW 1 5 N/A N/A N/A N/A N/A
4 AM Thu 71 71 WSW 1 5 N/A N/A N/A N/A N/A
5 AM Thu 70 70 WSW 2 6 N/A N/A N/A N/A N/A
6 AM Thu 70 70 WSW 2 6 N/A N/A N/A N/A N/A
7 AM Thu 70 70 WSW 2 5 N/A N/A N/A N/A N/A
8 AM Thu 70 70 WSW 2 5 N/A N/A N/A N/A N/A
9 AM Thu 69 69 WSW 2 5 N/A N/A N/A N/A N/A
10 AM Thu 69 69 SW 2 5 N/A N/A N/A N/A N/A
11 AM Thu 69 70 SSW 2 6 N/A N/A N/A N/A N/A
12 Noon Thu 69 71 SSW 3 8 N/A N/A N/A N/A N/A
1 PM Thu 70 72 SSW 4 9 N/A N/A N/A N/A N/A
2 PM Thu 71 73 SSW 4 10 N/A N/A N/A N/A N/A
3 PM Thu 71 72 SSW 4 10 N/A N/A N/A N/A N/A
4 PM Thu 70 71 SW 4 11 N/A N/A N/A N/A N/A
5 PM Thu 70 70 SW 4 10 N/A N/A N/A N/A N/A
6 PM Thu 68 68 SW 4 10 N/A N/A N/A N/A N/A
7 PM Thu 67 67 SW 4 10 N/A N/A N/A N/A N/A
8 PM Thu 67 67 SW 4 10 N/A N/A N/A N/A N/A
9 PM Thu 67 67 SW 4 10 N/A N/A N/A N/A N/A
10 PM Thu 68 68 SW 4 10 N/A N/A N/A N/A N/A
11 PM Thu 69 69 WSW 3 9 N/A N/A N/A N/A N/A
12 Midnight Fri 69 69 WSW 3 9 N/A N/A N/A N/A N/A
1 AM Fri 69 69 WSW 3 9 N/A N/A N/A N/A N/A
2 AM Fri 69 69 WSW 3 9 N/A N/A N/A N/A N/A
3 AM Fri 69 69 WSW 3 9 N/A N/A N/A N/A N/A
4 AM Fri 69 69 WSW 3 9 N/A N/A N/A N/A N/A
5 AM Fri 68 68 WSW 4 10 N/A N/A N/A N/A N/A
6 AM Fri 68 68 WSW 4 10 N/A N/A N/A N/A N/A
7 AM Fri 67 67 WSW 4 10 N/A N/A N/A N/A N/A
8 AM Fri 67 67 WSW 4 10 N/A N/A N/A N/A N/A
9 AM Fri 67 67 WSW 4 10 N/A N/A N/A N/A N/A
10 AM Fri 67 68 WSW 4 10 N/A N/A N/A N/A N/A
11 AM Fri 68 70 SW 5 11 N/A N/A N/A N/A N/A
12 Noon Fri 68 71 SW 5 11 N/A N/A N/A N/A N/A
1 PM Fri 69 72 SW 5 11 N/A N/A N/A N/A N/A
2 PM Fri 69 72 SW 5 11 N/A N/A N/A N/A N/A
3 PM Fri 68 70 SW 5 11 N/A N/A N/A N/A N/A
4 PM Fri 68 69 SW 5 11 N/A N/A N/A N/A N/A
5 PM Fri 67 67 SW 5 13 N/A N/A N/A N/A N/A
6 PM Fri 66 66 SW 5 13 N/A N/A N/A N/A N/A
7 PM Fri 65 65 SW 5 13 N/A N/A N/A N/A N/A
8 PM Fri 64 64 SW 5 13 N/A N/A N/A N/A N/A
9 PM Fri 65 65 SW 5 13 N/A N/A N/A N/A N/A
10 PM Fri 67 67 SW 5 13 N/A N/A N/A N/A N/A
11 PM Fri 68 68 WSW 3 9 N/A N/A N/A N/A N/A
12 Midnight Sat 69 69 WSW 3 9 N/A N/A N/A N/A N/A
1 AM Sat 70 70 WSW 3 9 N/A N/A N/A N/A N/A
2 AM Sat 70 70 WSW 3 9 N/A N/A N/A N/A N/A
3 AM Sat 69 69 WSW 3 9 N/A N/A N/A N/A N/A
4 AM Sat 68 68 WSW 3 9 N/A N/A N/A N/A N/A
5 AM Sat 67 67 WSW 3 8 N/A N/A N/A N/A N/A
6 AM Sat 67 67 WSW 3 8 N/A N/A N/A N/A N/A
7 AM Sat 68 68 WSW 3 8 N/A N/A N/A N/A N/A
8 AM Sat 68 68 WSW 3 8 N/A N/A N/A N/A N/A
9 AM Sat 68 68 WSW 3 8 N/A N/A N/A N/A N/A
10 AM Sat 67 68 WSW 3 8 N/A N/A N/A N/A N/A
11 AM Sat 66 68 WSW 4 9 N/A N/A N/A N/A N/A
12 Noon Sat 67 69 WSW 4 9 N/A N/A N/A N/A N/A
1 PM Sat 68 71 WSW 4 9 N/A N/A N/A N/A N/A
2 PM Sat 68 70 WSW 4 9 N/A N/A N/A N/A N/A
3 PM Sat 67 69 WSW 4 9 N/A N/A N/A N/A N/A
4 PM Sat 66 67 WSW 4 9 N/A N/A N/A N/A N/A
5 PM Sat 66 66 WSW 2 8 N/A N/A N/A N/A N/A
6 PM Sat 65 65 WSW 2 8 N/A N/A N/A N/A N/A
7 PM Sat 65 65 WSW 2 8 N/A N/A N/A N/A N/A
8 PM Sat 65 65 WSW 2 8 N/A N/A N/A N/A N/A
9 PM Sat 66 66 WSW 2 8 N/A N/A N/A N/A N/A
10 PM Sat 68 68 WSW 2 8 N/A N/A N/A N/A N/A

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]