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

Station:

KOAK

Date/Time:

13 JUL 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 Sat 63 63 W 5 8 1248 2040 0 Blue 1
1 AM Sat 61 61 W 5 8 1219 2040 0 Blue 0
2 AM Sat 60 60 WSW 5 9 1189 2040 0 Blue 0
3 AM Sat 59 59 WSW 5 10 1159 2040 0 Blue 0
4 AM Sat 59 59 WSW 5 10 1159 2040 0 Blue 0
5 AM Sat 58 58 SW 6 10 1130 2040 0 Blue 0
6 AM Sat 58 58 SW 5 10 1130 2040 0 Blue 0
7 AM Sat 58 58 SW 5 11 1130 2040 0 Blue 0
8 AM Sat 58 58 SW 6 11 1130 2040 0 Blue 0
9 AM Sat 58 58 SW 6 11 1130 2040 0 Blue 0
10 AM Sat 57 58 SSW 6 13 1130 2040 0 Blue 0
11 AM Sat 58 60 SSW 6 13 1189 2040 0 Blue 0
12 Noon Sat 61 63 SW 6 12 1248 2040 0 Blue 1
1 PM Sat 62 64 SW 8 12 1258 2040 0 Blue 2
2 PM Sat 62 64 SW 8 12 1258 2040 0 Blue 2
3 PM Sat 64 66 SW 8 12 1357 2040 0 Blue 4
4 PM Sat 62 63 WSW 6 11 1248 2040 0 Blue 1
5 PM Sat 61 62 WSW 6 11 1238 2040 0 Blue 0
6 PM Sat 62 62 WSW 6 11 1238 2040 0 Blue 0
7 PM Sat 61 61 WSW 5 11 1219 2040 0 Blue 0
8 PM Sat 60 60 WSW 5 10 1189 2040 0 Blue 0
9 PM Sat 60 60 WSW 5 10 1189 2040 0 Blue 0
10 PM Sat 60 60 WSW 5 10 1189 2040 0 Blue 0
11 PM Sat 60 60 WSW 5 10 1189 2040 0 Blue 0
12 Midnight Sun 60 60 WSW 5 9 1189 2040 0 Blue 0
1 AM Sun 60 60 WSW 5 9 1189 2040 0 Blue 0
2 AM Sun 60 60 WSW 5 9 1189 2040 0 Blue 0
3 AM Sun 59 59 WSW 5 9 1159 2040 0 Blue 0
4 AM Sun 59 59 SW 4 9 1159 2040 0 Blue 0
5 AM Sun 59 59 SW 5 9 1159 2040 0 Blue 0
6 AM Sun 57 57 SW 4 8 1100 2040 0 Blue 0
7 AM Sun 58 58 SW 4 8 1130 2040 0 Blue 0
8 AM Sun 58 58 SSW 4 8 1130 2040 0 Blue 0
9 AM Sun 58 59 SSW 4 9 1159 2040 0 Blue 0
10 AM Sun 59 61 SW 4 9 1219 2040 0 Blue 0
11 AM Sun 59 63 SW 5 10 1248 2040 0 Blue 1
12 Noon Sun 61 66 SW 5 10 1357 2040 0 Blue 4
1 PM Sun 62 68 SW 5 10 1403 2040 0 Blue 6
2 PM Sun 64 70 SW 5 10 1450 2040 0 Blue 8
3 PM Sun 64 70 SW 6 10 1450 2040 0 Blue 8
4 PM Sun 63 67 WSW 6 10 1385 2040 0 Blue 5
5 PM Sun 62 65 WSW 5 10 1296 2040 0 Blue 3
6 PM Sun 62 63 WSW 5 10 1248 2040 0 Blue 1
7 PM Sun 62 62 WSW 5 9 1238 2040 0 Blue 0
8 PM Sun 61 61 WSW 5 9 1219 2040 0 Blue 0
9 PM Sun 61 61 WSW 4 8 1219 2040 0 Blue 0
10 PM Sun 60 60 WSW 4 8 1189 2040 0 Blue 0
11 PM Sun 60 60 WSW 4 6 1189 2040 0 Blue 0
12 Midnight Mon 60 60 WSW 4 6 1189 2040 0 Blue 0
1 AM Mon 59 59 WSW 4 6 1159 2040 0 Blue 0
2 AM Mon 59 59 WSW 4 6 1159 2040 0 Blue 0
3 AM Mon 59 59 WSW 4 6 1159 2040 0 Blue 0
4 AM Mon 59 59 WSW 4 6 1159 2040 0 Blue 0
5 AM Mon 59 59 WSW 4 6 1159 2040 0 Blue 0
6 AM Mon 59 59 WSW 4 6 1159 2040 0 Blue 0
7 AM Mon 59 59 WSW 3 6 1159 2040 0 Blue 0
8 AM Mon 59 59 WSW 3 6 1159 2040 0 Blue 0
9 AM Mon 59 60 WSW 4 8 1189 2040 0 Blue 0
10 AM Mon 59 61 SW 4 9 1219 2040 0 Blue 0
11 AM Mon 60 64 SW 5 9 1258 2040 0 Blue 2
12 Noon Mon 61 67 SW 5 10 1385 2040 0 Blue 5
1 PM Mon 63 69 WSW 5 10 1422 2040 0 Blue 7
2 PM Mon 64 71 WSW 5 10 1530 2040 0 Blue 9
3 PM Mon 65 71 WSW 6 11 1530 2040 0 Blue 9
4 PM Mon 65 70 WSW 6 11 1450 2040 0 Blue 8
5 PM Mon 64 67 WSW 6 11 1385 2040 0 Blue 5
6 PM Mon 63 64 WSW 6 11 1258 2040 0 Blue 2
7 PM Mon 62 62 W 5 10 1238 2040 0 Blue 0
8 PM Mon 62 62 W 5 9 1238 2040 0 Blue 0
9 PM Mon 61 61 W 4 9 1219 2040 0 Blue 0
10 PM Mon 61 61 WSW 4 8 1219 2040 0 Blue 0
11 PM Mon 61 61 WSW 4 6 1219 2040 0 Blue 0
12 Midnight Tue 61 61 WSW 4 6 1219 2040 0 Blue 0
1 AM Tue 61 61 WSW 3 6 1219 2040 0 Blue 0
2 AM Tue 60 60 WSW 3 6 1189 2040 0 Blue 0
3 AM Tue 60 60 WSW 3 6 1189 2040 0 Blue 0
4 AM Tue 59 59 WSW 3 6 1159 2040 0 Blue 0
5 AM Tue 59 59 WSW 3 6 1159 2040 0 Blue 0
6 AM Tue 59 59 WSW 3 6 1159 2040 0 Blue 0
7 AM Tue 59 59 WSW 3 6 1159 2040 0 Blue 0
8 AM Tue 60 60 WSW 3 6 1189 2040 0 Blue 0
9 AM Tue 59 60 WSW 4 8 1189 2040 0 Blue 0
10 AM Tue 59 61 SW 4 9 1219 2040 0 Blue 0
11 AM Tue 60 64 SW 5 9 1258 2040 0 Blue 2
12 Noon Tue 61 66 SW 5 10 1357 2040 0 Blue 4
1 PM Tue 63 70 WSW 5 10 1450 2040 0 Blue 8
2 PM Tue 64 71 WSW 5 10 1530 2040 0 Blue 9
3 PM Tue 64 70 WSW 6 11 1450 2040 0 Blue 8
4 PM Tue 64 69 WSW 6 11 1422 2040 0 Blue 7
5 PM Tue 63 66 WSW 6 11 1357 2040 0 Blue 4
6 PM Tue 63 64 WSW 6 11 1258 2040 0 Blue 2
7 PM Tue 62 62 W 6 10 1238 2040 0 Blue 0
8 PM Tue 62 62 W 5 9 1238 2040 0 Blue 0
9 PM Tue 61 61 W 5 9 1219 2040 0 Blue 0
10 PM Tue 61 61 W 4 9 1219 2040 0 Blue 0
11 PM Tue 61 61 W 4 8 1219 2040 0 Blue 0
12 Midnight Wed 60 60 W 4 8 1189 2040 0 Blue 0
1 AM Wed 60 60 WSW 4 8 1189 2040 0 Blue 0
2 AM Wed 60 60 WSW 4 6 1189 2040 0 Blue 0
3 AM Wed 60 60 WSW 4 6 1189 2040 0 Blue 0
4 AM Wed 60 60 WSW 4 8 1189 2040 0 Blue 0
5 AM Wed 60 60 WSW 4 8 1189 2040 0 Blue 0
6 AM Wed 59 59 WSW 4 8 1159 2040 0 Blue 0
7 AM Wed 59 59 WSW 3 8 1159 2040 0 Blue 0
8 AM Wed 59 59 WSW 3 8 1159 2040 0 Blue 0
9 AM Wed 59 60 WSW 4 8 1189 2040 0 Blue 0
10 AM Wed 60 62 WSW 4 9 1238 2040 0 Blue 0
11 AM Wed 60 64 WSW 5 9 1258 2040 0 Blue 2
12 Noon Wed 61 67 WSW 5 10 1385 2040 0 Blue 5
1 PM Wed 63 69 WSW 5 10 1422 2040 0 Blue 7
2 PM Wed 64 71 WSW 6 11 1530 2040 0 Blue 9
3 PM Wed 64 70 WSW 6 11 1450 2040 0 Blue 8
4 PM Wed 64 69 W 8 12 1422 2040 0 Blue 7
5 PM Wed 64 67 W 8 12 1385 2040 0 Blue 5
6 PM Wed 64 65 W 8 12 1296 2040 0 Blue 3
7 PM Wed 63 63 W 8 12 1248 2040 0 Blue 1
8 PM Wed 62 62 W 6 11 1238 2040 0 Blue 0
9 PM Wed 62 62 W 6 11 1238 2040 0 Blue 0
10 PM Wed 62 62 W 6 10 1238 2040 0 Blue 0
11 PM Wed 62 62 W 5 10 1238 2040 0 Blue 0
12 Midnight Thu 61 61 W 5 10 1219 2040 0 Blue 0
1 AM Thu 61 61 W 5 10 1219 2040 0 Blue 0
2 AM Thu 60 60 W 5 10 1189 2040 0 Blue 0
3 AM Thu 60 60 W 5 10 1189 2040 0 Blue 0
4 AM Thu 60 60 W 5 9 1189 2040 0 Blue 0
5 AM Thu 60 60 W 5 9 1189 2040 0 Blue 0
6 AM Thu 60 60 W 4 9 1189 2040 0 Blue 0
7 AM Thu 60 60 W 4 9 1189 2040 0 Blue 0
8 AM Thu 60 60 W 4 9 1189 2040 0 Blue 0
9 AM Thu 61 62 W 4 9 1238 2040 0 Blue 0
10 AM Thu 61 64 W 4 9 1258 2040 0 Blue 2
11 AM Thu 62 67 W 5 10 1385 2040 0 Blue 5
12 Noon Thu 64 70 W 5 10 1450 2040 0 Blue 8
1 PM Thu 66 73 W 6 11 1653 2040 0 Blue 11
2 PM Thu 68 75 W 6 12 1686 2040 0 Blue 13
3 PM Thu 68 74 W 8 12 1670 2040 0 Blue 12
4 PM Thu 68 73 W 9 13 1653 2040 0 Blue 11
5 PM Thu 67 70 W 9 13 1450 2040 0 Blue 8
6 PM Thu 66 67 W 9 13 1385 2040 0 Blue 5
7 PM Thu 65 65 W 8 13 1296 2040 0 Blue 3
8 PM Thu 64 64 W 8 13 1258 2040 0 Blue 2
9 PM Thu 64 64 W 8 13 1258 2040 0 Blue 2
10 PM Thu 64 64 WNW 8 13 1258 2040 0 Blue 2

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]