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

Station:

KOAK

Date/Time:

14 APR 2024

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 Sun 44 44 E 13 23 1174 2040 0 Blue 0
1 AM Sun 44 44 NE 16 19 1174 2040 0 Blue 0
2 AM Sun 44 44 ENE 18 23 1174 2040 0 Blue 0
3 AM Sun 42 42 ENE 14 21 571 2040 0 Blue 0
4 AM Sun 44 44 ENE 16 21 1174 2040 0 Blue 0
5 AM Sun 44 44 NE 14 19 1174 2040 0 Blue 0
6 AM Sun 44 44 NE 13 18 1174 2040 0 Blue 0
7 AM Sun 45 45 NE 14 20 1284 2040 0 Blue 1
8 AM Sun 45 45 NE 13 19 1284 2040 0 Blue 1
9 AM Sun 45 45 NNE 11 14 1284 2040 0 Blue 1
10 AM Sun 46 47 NNE 10 12 2077 2040 0 Blue 3
11 AM Sun 47 49 N 9 12 3493 2040 0 White 5
12 Noon Sun 48 51 NNW 6 11 3924 2515 475 White 7
1 PM Sun 49 52 NW 6 11 4139 3294 1254 White 8
2 PM Sun 50 53 WNW 8 11 4353 4023 1983 White 9
3 PM Sun 50 52 WNW 10 12 4139 3294 1254 White 8
4 PM Sun 50 51 WNW 11 13 3924 2515 475 White 7
5 PM Sun 50 51 W 11 16 3924 2515 475 White 7
6 PM Sun 49 49 W 10 16 3493 2040 0 White 5
7 PM Sun 48 48 W 9 12 2554 2040 0 Blue 4
8 PM Sun 47 47 WNW 8 11 2077 2040 0 Blue 3
9 PM Sun 47 47 NW 9 13 2077 2040 0 Blue 3
10 PM Sun 47 47 NW 10 16 2077 2040 0 Blue 3
11 PM Sun 47 47 NW 11 19 2077 2040 0 Blue 3
12 Midnight Mon 47 47 NNW 13 21 2077 2040 0 Blue 3
1 AM Mon 46 46 NNW 13 21 1613 2040 0 Blue 2
2 AM Mon 46 46 NNW 11 20 1613 2040 0 Blue 2
3 AM Mon 45 45 NNW 11 19 1284 2040 0 Blue 1
4 AM Mon 45 45 NNW 11 19 1284 2040 0 Blue 1
5 AM Mon 44 44 NNW 10 16 1174 2040 0 Blue 0
6 AM Mon 45 45 N 9 12 1284 2040 0 Blue 1
7 AM Mon 45 45 N 6 10 1284 2040 0 Blue 1
8 AM Mon 46 46 N 4 6 1613 2040 0 Blue 2
9 AM Mon 48 49 NNW 2 5 3493 2040 0 White 5
10 AM Mon 49 51 WNW 0 4 3924 2515 475 White 7
11 AM Mon 50 52 W 4 6 4139 3294 1254 White 8
12 Noon Mon 52 55 W 4 6 4793 4782 2742 White 11
1 PM Mon 52 55 W 4 6 4793 4782 2742 White 11
2 PM Mon 53 59 W 8 10 5635 5635 3595 White 15
3 PM Mon 53 58 W 8 10 5425 5425 3385 White 14
4 PM Mon 53 56 W 8 10 5004 5004 2964 White 12
5 PM Mon 53 55 W 8 10 4793 4782 2742 White 11
6 PM Mon 52 52 W 8 10 4139 3294 1254 White 8
7 PM Mon 51 51 W 8 10 3924 2515 475 White 7
8 PM Mon 50 50 WNW 11 12 3709 2063 23 White 6
9 PM Mon 49 49 WNW 11 12 3493 2040 0 White 5
10 PM Mon 49 49 WNW 11 12 3493 2040 0 White 5
11 PM Mon 49 49 WNW 6 10 3493 2040 0 White 5
12 Midnight Tue 48 48 WNW 6 10 2554 2040 0 Blue 4
1 AM Tue 48 48 WNW 6 10 2554 2040 0 Blue 4
2 AM Tue 47 47 WNW 5 8 2077 2040 0 Blue 3
3 AM Tue 47 47 WNW 5 8 2077 2040 0 Blue 3
4 AM Tue 47 47 WNW 5 8 2077 2040 0 Blue 3
5 AM Tue 47 47 NNW 5 6 2077 2040 0 Blue 3
6 AM Tue 48 48 NNW 5 6 2554 2040 0 Blue 4
7 AM Tue 48 48 NNW 5 6 2554 2040 0 Blue 4
8 AM Tue 50 50 NNW 5 6 3709 2063 23 White 6
9 AM Tue 51 51 NNW 5 6 3924 2515 475 White 7
10 AM Tue 53 54 NNW 5 6 4574 4464 2424 White 10
11 AM Tue 54 59 W 5 9 5635 5635 3595 White 15
12 Noon Tue 55 61 W 5 9 6053 6053 4013 White 17
1 PM Tue 56 62 W 5 9 6260 6260 4220 White 18
2 PM Tue 57 63 W 9 11 6468 6468 4428 White 19
3 PM Tue 58 63 W 9 11 6468 6468 4428 White 19
4 PM Tue 58 61 W 9 11 6053 6053 4013 White 17
5 PM Tue 57 58 W 11 16 5425 5425 3385 White 14
6 PM Tue 56 56 W 11 16 5004 5004 2964 White 12
7 PM Tue 55 55 W 11 16 4793 4782 2742 White 11
8 PM Tue 54 54 WNW 10 13 4574 4464 2424 White 10
9 PM Tue 53 53 WNW 10 13 4353 4023 1983 White 9
10 PM Tue 52 52 WNW 10 13 4139 3294 1254 White 8
11 PM Tue 52 52 WNW 9 11 4139 3294 1254 White 8
12 Midnight Wed 51 51 WNW 9 11 3924 2515 475 White 7
1 AM Wed 50 50 WNW 9 11 3709 2063 23 White 6
2 AM Wed 50 50 NW 6 10 3709 2063 23 White 6
3 AM Wed 50 50 NW 6 10 3709 2063 23 White 6
4 AM Wed 49 49 NW 6 10 3493 2040 0 White 5
5 AM Wed 50 50 NNW 6 10 3709 2063 23 White 6
6 AM Wed 50 50 NNW 6 10 3709 2063 23 White 6
7 AM Wed 51 51 NNW 6 10 3924 2515 475 White 7
8 AM Wed 52 52 NNE 6 9 4139 3294 1254 White 8
9 AM Wed 54 55 NNE 6 9 4793 4782 2742 White 11
10 AM Wed 56 58 NNE 6 9 5425 5425 3385 White 14
11 AM Wed 58 62 N 6 10 6260 6260 4220 White 18
12 Noon Wed 60 64 N 6 10 6674 6674 4634 White 20
1 PM Wed 61 66 N 6 10 7085 7085 5045 White 22
2 PM Wed 62 67 WNW 10 12 7290 7290 5250 White 23
3 PM Wed 63 67 WNW 10 12 7290 7290 5250 White 23
4 PM Wed 63 66 WNW 10 12 7085 7085 5045 White 22
5 PM Wed 62 63 WNW 11 14 6468 6468 4428 White 19
6 PM Wed 61 61 WNW 11 14 6053 6053 4013 White 17
7 PM Wed 60 60 WNW 11 14 5845 5845 3805 White 16
8 PM Wed 58 58 WNW 10 12 5425 5425 3385 White 14
9 PM Wed 56 56 WNW 10 12 5004 5004 2964 White 12
10 PM Wed 55 55 WNW 10 12 4793 4782 2742 White 11
11 PM Wed 54 54 WNW 6 10 4574 4464 2424 White 10
12 Midnight Thu 53 53 WNW 6 10 4353 4023 1983 White 9
1 AM Thu 53 53 WNW 6 10 4353 4023 1983 White 9
2 AM Thu 52 52 W 4 8 4139 3294 1254 White 8
3 AM Thu 52 52 W 4 8 4139 3294 1254 White 8
4 AM Thu 51 51 W 4 8 3924 2515 475 White 7
5 AM Thu 51 51 NW 4 8 3924 2515 475 White 7
6 AM Thu 51 51 NW 4 8 3924 2515 475 White 7
7 AM Thu 52 52 NW 4 8 4139 3294 1254 White 8
8 AM Thu 54 54 NNW 5 8 4574 4464 2424 White 10
9 AM Thu 55 56 NNW 5 8 5004 5004 2964 White 12
10 AM Thu 57 58 NNW 5 8 5425 5425 3385 White 14
11 AM Thu 59 62 W 6 10 6260 6260 4220 White 18
12 Noon Thu 60 64 W 6 10 6674 6674 4634 White 20
1 PM Thu 62 66 W 6 10 7085 7085 5045 White 22
2 PM Thu 62 66 W 8 12 7085 7085 5045 White 22
3 PM Thu 63 67 W 8 12 7290 7290 5250 White 23
4 PM Thu 62 64 W 8 12 6674 6674 4634 White 20
5 PM Thu 61 62 W 11 13 6260 6260 4220 White 18
6 PM Thu 60 60 W 11 13 5845 5845 3805 White 16
7 PM Thu 58 58 W 11 13 5425 5425 3385 White 14
8 PM Thu 56 56 W 10 13 5004 5004 2964 White 12
9 PM Thu 54 54 W 10 13 4574 4464 2424 White 10
10 PM Thu 53 53 W 10 13 4353 4023 1983 White 9
11 PM Thu 52 52 W 9 11 4139 3294 1254 White 8
12 Midnight Fri 51 51 W 9 11 3924 2515 475 White 7
1 AM Fri 50 50 W 9 11 3709 2063 23 White 6
2 AM Fri 50 50 W 9 11 3709 2063 23 White 6
3 AM Fri 50 50 W 9 11 3709 2063 23 White 6
4 AM Fri 50 50 W 9 11 3709 2063 23 White 6
5 AM Fri 50 50 W 9 11 3709 2063 23 White 6
6 AM Fri 50 50 W 9 11 3709 2063 23 White 6
7 AM Fri 51 51 W 9 11 3924 2515 475 White 7
8 AM Fri 52 52 W 9 12 4139 3294 1254 White 8
9 AM Fri 53 54 W 9 12 4574 4464 2424 White 10
10 AM Fri 54 56 W 9 12 5004 5004 2964 White 12
11 AM Fri 56 60 W 9 13 5845 5845 3805 White 16
12 Noon Fri 57 62 W 9 13 6260 6260 4220 White 18
1 PM Fri 58 63 W 9 13 6468 6468 4428 White 19
2 PM Fri 58 63 W 13 16 6468 6468 4428 White 19
3 PM Fri 58 62 W 13 16 6260 6260 4220 White 18
4 PM Fri 58 61 W 13 16 6053 6053 4013 White 17
5 PM Fri 57 58 W 17 19 5425 5425 3385 White 14
6 PM Fri 56 56 W 17 19 5004 5004 2964 White 12
7 PM Fri 54 54 W 17 19 4574 4464 2424 White 10
8 PM Fri 53 53 W 14 18 4353 4023 1983 White 9
9 PM Fri 52 52 W 14 18 4139 3294 1254 White 8
10 PM Fri 51 51 W 14 18 3924 2515 475 White 7

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]