Detailed Predictions for: Mt Tamalpais
Launch Lat, Long, Altitude (f): 37.90719, -122.62, 2040
LZ Altitude (f): 0
Sounding

Station:

KOAK

Date/Time:

5 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 Tue 55 55 NNW 5 5 883 2040 0 Blue 0
1 AM Tue 54 54 NNW 5 6 883 2040 0 Blue 0
2 AM Tue 55 55 N 5 6 883 2040 0 Blue 0
3 AM Tue 54 54 N 5 6 883 2040 0 Blue 0
4 AM Tue 53 53 N 5 6 883 2040 0 Blue 0
5 AM Tue 54 54 N 5 6 883 2040 0 Blue 0
6 AM Tue 54 54 NNE 5 6 883 2040 0 Blue 0
7 AM Tue 53 53 NNE 5 6 883 2040 0 Blue 0
8 AM Tue 53 53 NNE 5 8 883 2040 0 Blue 0
9 AM Tue 54 54 NNE 6 9 883 2040 0 Blue 0
10 AM Tue 54 54 NE 6 9 883 2040 0 Blue 0
11 AM Tue 56 57 NE 6 10 883 2040 0 Blue 0
12 Noon Tue 57 58 NNE 5 9 1115 2040 0 Blue 0
1 PM Tue 58 59 NNE 5 9 1498 2040 0 Blue 0
2 PM Tue 58 58 N 5 9 1115 2040 0 Blue 0
3 PM Tue 57 57 N 5 8 883 2040 0 Blue 0
4 PM Tue 57 57 N 5 8 883 2040 0 Blue 0
5 PM Tue 56 56 N 5 6 883 2040 0 Blue 0
6 PM Tue 55 55 NNW 5 5 883 2040 0 Blue 0
7 PM Tue 55 55 WNW 5 5 883 2040 0 Blue 0
8 PM Tue 55 55 NW 5 5 883 2040 0 Blue 0
9 PM Tue 55 55 WNW 4 5 883 2040 0 Blue 0
10 PM Tue 54 54 SW 5 5 883 2040 0 Blue 0
11 PM Tue 54 54 WSW 4 4 883 2040 0 Blue 0
12 Midnight Wed 54 54 WSW 4 5 883 2040 0 Blue 0
1 AM Wed 53 53 WSW 5 6 883 2040 0 Blue 0
2 AM Wed 53 53 W 5 6 883 2040 0 Blue 0
3 AM Wed 53 53 W 6 8 883 2040 0 Blue 0
4 AM Wed 52 52 WSW 6 10 883 2040 0 Blue 0
5 AM Wed 53 53 SW 8 10 883 2040 0 Blue 0
6 AM Wed 53 53 SW 10 11 883 2040 0 Blue 0
7 AM Wed 53 53 SSW 11 13 883 2040 0 Blue 0
8 AM Wed 54 54 SSW 14 18 883 2040 0 Blue 0
9 AM Wed 53 53 S 17 21 883 2040 0 Blue 0
10 AM Wed 53 53 SSW 17 23 883 2040 0 Blue 0
11 AM Wed 53 53 SSW 17 23 883 2040 0 Blue 0
12 Noon Wed 53 53 SSW 17 23 883 2040 0 Blue 0
1 PM Wed 53 53 SW 17 20 883 2040 0 Blue 0
2 PM Wed 53 53 SW 17 20 883 2040 0 Blue 0
3 PM Wed 53 53 SW 17 20 883 2040 0 Blue 0
4 PM Wed 53 53 W 12 17 883 2040 0 Blue 0
5 PM Wed 53 53 W 12 17 883 2040 0 Blue 0
6 PM Wed 53 53 W 12 17 883 2040 0 Blue 0
7 PM Wed 53 53 WNW 13 16 883 2040 0 Blue 0
8 PM Wed 53 53 WNW 13 16 883 2040 0 Blue 0
9 PM Wed 53 53 WNW 13 16 883 2040 0 Blue 0
10 PM Wed 53 53 WNW 11 12 883 2040 0 Blue 0
11 PM Wed 53 53 WNW 11 12 883 2040 0 Blue 0
12 Midnight Thu 53 53 WNW 11 12 883 2040 0 Blue 0
1 AM Thu 52 52 WNW 12 13 883 2040 0 Blue 0
2 AM Thu 52 52 WNW 12 13 883 2040 0 Blue 0
3 AM Thu 52 52 WNW 12 13 883 2040 0 Blue 0
4 AM Thu 52 52 NW 13 18 883 2040 0 Blue 0
5 AM Thu 51 51 NW 13 18 883 2040 0 Blue 0
6 AM Thu 51 51 NW 13 18 883 2040 0 Blue 0
7 AM Thu 50 50 NW 11 14 883 2040 0 Blue 0
8 AM Thu 51 51 NW 11 14 883 2040 0 Blue 0
9 AM Thu 52 52 NW 11 14 883 2040 0 Blue 0
10 AM Thu 52 52 WNW 12 18 883 2040 0 Blue 0
11 AM Thu 53 53 WNW 12 18 883 2040 0 Blue 0
12 Noon Thu 53 53 WNW 12 18 883 2040 0 Blue 0
1 PM Thu 53 53 WNW 13 17 883 2040 0 Blue 0
2 PM Thu 53 53 WNW 13 17 883 2040 0 Blue 0
3 PM Thu 52 52 WNW 13 17 883 2040 0 Blue 0
4 PM Thu 52 52 WNW 13 20 883 2040 0 Blue 0
5 PM Thu 52 52 WNW 13 20 883 2040 0 Blue 0
6 PM Thu 51 51 WNW 13 20 883 2040 0 Blue 0
7 PM Thu 51 51 NW 14 20 883 2040 0 Blue 0
8 PM Thu 51 51 NW 14 20 883 2040 0 Blue 0
9 PM Thu 51 51 NW 14 20 883 2040 0 Blue 0
10 PM Thu 51 51 NW 16 23 883 2040 0 Blue 0
11 PM Thu 51 51 NW 16 23 883 2040 0 Blue 0
12 Midnight Fri 50 50 NW 16 23 883 2040 0 Blue 0
1 AM Fri 50 50 NNW 14 23 883 2040 0 Blue 0
2 AM Fri 49 49 NNW 14 23 883 2040 0 Blue 0
3 AM Fri 49 49 NNW 14 23 883 2040 0 Blue 0
4 AM Fri 48 48 NNW 13 17 883 2040 0 Blue 0
5 AM Fri 47 47 NNW 13 17 883 2040 0 Blue 0
6 AM Fri 46 46 NNW 13 17 883 2040 0 Blue 0
7 AM Fri 45 45 N 10 13 883 2040 0 Blue 0
8 AM Fri 46 46 N 10 13 883 2040 0 Blue 0
9 AM Fri 47 47 N 10 13 883 2040 0 Blue 0
10 AM Fri 48 49 N 9 12 883 2040 0 Blue 0
11 AM Fri 50 52 N 9 12 883 2040 0 Blue 0
12 Noon Fri 51 53 N 9 12 883 2040 0 Blue 0
1 PM Fri 52 53 NNW 10 13 883 2040 0 Blue 0
2 PM Fri 52 53 NNW 10 13 883 2040 0 Blue 0
3 PM Fri 52 52 NNW 10 13 883 2040 0 Blue 0
4 PM Fri 51 51 NW 10 13 883 2040 0 Blue 0
5 PM Fri 50 50 NW 10 13 883 2040 0 Blue 0
6 PM Fri 50 50 NW 10 13 883 2040 0 Blue 0
7 PM Fri 49 49 NNW 9 11 883 2040 0 Blue 0
8 PM Fri 49 49 NNW 9 11 883 2040 0 Blue 0
9 PM Fri 49 49 NNW 9 11 883 2040 0 Blue 0
10 PM Fri 49 49 NNW 6 9 883 2040 0 Blue 0
11 PM Fri 49 49 NNW 6 9 883 2040 0 Blue 0
12 Midnight Sat 48 48 NNW 6 9 883 2040 0 Blue 0
1 AM Sat 48 48 N 5 8 883 2040 0 Blue 0
2 AM Sat 47 47 N 5 8 883 2040 0 Blue 0
3 AM Sat 47 47 N 5 8 883 2040 0 Blue 0
4 AM Sat 47 47 NNE 6 9 883 2040 0 Blue 0
5 AM Sat 47 47 NNE 6 9 883 2040 0 Blue 0
6 AM Sat 47 47 NNE 6 9 883 2040 0 Blue 0
7 AM Sat 47 47 NE 6 10 883 2040 0 Blue 0
8 AM Sat 47 47 NE 6 10 883 2040 0 Blue 0
9 AM Sat 47 47 NE 6 10 883 2040 0 Blue 0
10 AM Sat 48 48 NE 8 11 883 2040 0 Blue 0
11 AM Sat 50 51 NE 8 11 883 2040 0 Blue 0
12 Noon Sat 51 52 NE 8 11 883 2040 0 Blue 0
1 PM Sat 52 53 N 6 10 883 2040 0 Blue 0
2 PM Sat 52 52 N 6 10 883 2040 0 Blue 0
3 PM Sat 52 52 N 6 10 883 2040 0 Blue 0
4 PM Sat 52 52 NNW 6 10 883 2040 0 Blue 0
5 PM Sat 51 51 NNW 6 10 883 2040 0 Blue 0
6 PM Sat 51 51 NNW 6 10 883 2040 0 Blue 0
7 PM Sat 50 50 NNW 6 9 883 2040 0 Blue 0
8 PM Sat 50 50 NNW 6 9 883 2040 0 Blue 0
9 PM Sat 50 50 NNW 6 9 883 2040 0 Blue 0
10 PM Sat 51 51 N 6 8 883 2040 0 Blue 0
11 PM Sat 51 51 N 6 8 883 2040 0 Blue 0
12 Midnight Sun 50 50 N 6 8 883 2040 0 Blue 0
1 AM Sun 50 50 NNE 5 8 883 2040 0 Blue 0
2 AM Sun 50 50 NNE 5 8 883 2040 0 Blue 0
3 AM Sun 50 50 NNE 5 8 883 2040 0 Blue 0
4 AM Sun 50 50 NNE 6 10 883 2040 0 Blue 0
5 AM Sun 50 50 NNE 6 10 883 2040 0 Blue 0
6 AM Sun 50 50 NNE 6 10 883 2040 0 Blue 0
7 AM Sun 50 50 NE 6 11 883 2040 0 Blue 0
8 AM Sun 50 50 NE 6 11 883 2040 0 Blue 0
9 AM Sun 50 50 NE 6 11 883 2040 0 Blue 0
10 AM Sun 51 51 NNE 6 10 883 2040 0 Blue 0
11 AM Sun 52 52 NNE 6 10 883 2040 0 Blue 0
12 Noon Sun 53 53 NNE 6 10 883 2040 0 Blue 0
1 PM Sun 54 54 N 8 10 883 2040 0 Blue 0
2 PM Sun 54 54 N 8 10 883 2040 0 Blue 0
3 PM Sun 53 53 N 8 10 883 2040 0 Blue 0
4 PM Sun 53 53 NNW 8 10 883 2040 0 Blue 0
5 PM Sun 53 53 NNW 8 10 883 2040 0 Blue 0
6 PM Sun 53 53 NNW 8 10 883 2040 0 Blue 0
7 PM Sun 53 53 NNW 8 9 883 2040 0 Blue 0
8 PM Sun 53 53 NNW 8 9 883 2040 0 Blue 0
9 PM Sun 53 53 NNW 8 9 883 2040 0 Blue 0
10 PM Sun 54 54 N 6 9 883 2040 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]