Detailed Predictions for: Mt Tamalpais
Launch Altitude (f): 2040
LZ Altitude (f): 0
Sounding

Station:

KOAK

Date/Time:

22 MAR 2019

Temp/Wind data from:

NOAA Digital Forecast

Site Forecasts
Time
(Local)
High
Temp

Puddle
Temp

Wind
(mph)
Thermal
Ceiling

(ft)
Soaring
Ceiling

(ft)
Above
Launch

(ft)
Thermal
Type
Thermal
Index

(F)
5 AM Fri 45 45 S 10 577 2040 0 Blue 0
6 AM Fri 45 45 S 10 577 2040 0 Blue 0
7 AM Fri 44 44 S 10 577 2040 0 Blue 0
8 AM Fri 44 44 SE 8 577 2040 0 Blue 0
9 AM Fri 46 46 SE 8 577 2040 0 Blue 0
10 AM Fri 48 48 SE 8 1274 2040 0 Blue 0
11 AM Fri 50 50 S 18 2072 2040 0 Blue 2
12 Noon Fri 51 51 S 18 2439 2040 0 Blue 3
1 PM Fri 52 52 S 18 2712 2040 0 Blue 4
2 PM Fri 53 53 S 22 2843 2060 20 Blue 5
3 PM Fri 53 53 S 22 2843 2060 20 Blue 5
4 PM Fri 53 53 S 22 2843 2060 20 Blue 5
5 PM Fri 52 52 S 18 2712 2040 0 Blue 4
6 PM Fri 51 51 S 18 2439 2040 0 Blue 3
7 PM Fri 49 49 S 18 1687 2040 0 Blue 1
8 PM Fri 48 48 S 17 1274 2040 0 Blue 0
9 PM Fri 47 47 S 17 577 2040 0 Blue 0
10 PM Fri 46 46 S 17 577 2040 0 Blue 0
11 PM Fri 46 46 NW 10 577 2040 0 Blue 0
12 Midnight Sat 45 45 NW 10 577 2040 0 Blue 0
1 AM Sat 45 45 NW 10 577 2040 0 Blue 0
2 AM Sat 45 45 NW 20 577 2040 0 Blue 0
3 AM Sat 45 45 NW 20 577 2040 0 Blue 0
4 AM Sat 44 44 NW 20 577 2040 0 Blue 0
5 AM Sat 44 44 NW 18 577 2040 0 Blue 0
6 AM Sat 44 44 NW 18 577 2040 0 Blue 0
7 AM Sat 44 44 NW 18 577 2040 0 Blue 0
8 AM Sat 44 44 NW 16 577 2040 0 Blue 0
9 AM Sat 45 45 NW 16 577 2040 0 Blue 0
10 AM Sat 47 48 NW 16 1274 2040 0 Blue 0
11 AM Sat 50 52 W 17 2712 2040 0 Blue 4
12 Noon Sat 51 54 W 17 2973 2423 383 Blue 6
1 PM Sat 52 56 W 17 3671 2835 795 Blue 8
2 PM Sat 53 57 W 18 3960 2965 925 Blue 9
3 PM Sat 53 56 W 18 3671 2835 795 Blue 8
4 PM Sat 53 55 W 18 3251 2705 665 Blue 7
5 PM Sat 52 53 W 18 2843 2060 20 Blue 5
6 PM Sat 51 51 W 18 2439 2040 0 Blue 3
7 PM Sat 48 48 W 18 1274 2040 0 Blue 0
8 PM Sat 47 47 NW 15 577 2040 0 Blue 0
9 PM Sat 46 46 NW 15 577 2040 0 Blue 0
10 PM Sat 46 46 NW 15 577 2040 0 Blue 0
11 PM Sat 45 45 N 6 577 2040 0 Blue 0
12 Midnight Sun 45 45 N 6 577 2040 0 Blue 0
1 AM Sun 44 44 N 6 577 2040 0 Blue 0
2 AM Sun 44 44 NE 6 577 2040 0 Blue 0
3 AM Sun 44 44 NE 6 577 2040 0 Blue 0
4 AM Sun 44 44 NE 6 577 2040 0 Blue 0
5 AM Sun 43 43 NE 13 577 2040 0 Blue 0
6 AM Sun 43 43 NE 13 577 2040 0 Blue 0
7 AM Sun 43 43 NE 13 577 2040 0 Blue 0
8 AM Sun 43 43 NE 14 577 2040 0 Blue 0
9 AM Sun 44 44 NE 14 577 2040 0 Blue 0
10 AM Sun 48 49 NE 14 1687 2040 0 Blue 1
11 AM Sun 51 53 E 12 2843 2060 20 Blue 5
12 Noon Sun 53 56 E 12 3671 2835 795 Blue 8
1 PM Sun 54 57 E 12 3960 2965 925 Blue 9
2 PM Sun 55 58 S 10 4332 3222 1182 Blue 10
3 PM Sun 55 57 S 10 3960 2965 925 Blue 9
4 PM Sun 55 56 S 10 3671 2835 795 Blue 8
5 PM Sun 54 54 S 16 2973 2423 383 Blue 6
6 PM Sun 53 53 S 16 2843 2060 20 Blue 5
7 PM Sun 50 50 S 16 2072 2040 0 Blue 2
8 PM Sun 49 49 S 22 1687 2040 0 Blue 1
9 PM Sun 48 48 S 22 1274 2040 0 Blue 0
10 PM Sun 48 48 S 22 1274 2040 0 Blue 0
11 PM Sun 47 47 S 38 577 2040 0 Blue 0
12 Midnight Mon 47 47 S 38 577 2040 0 Blue 0
1 AM Mon 46 46 S 38 577 2040 0 Blue 0
2 AM Mon 46 46 SW 22 577 2040 0 Blue 0
3 AM Mon 46 46 SW 22 577 2040 0 Blue 0
4 AM Mon 46 46 SW 22 577 2040 0 Blue 0
5 AM Mon 45 45 W 14 577 2040 0 Blue 0
6 AM Mon 45 45 W 14 577 2040 0 Blue 0
7 AM Mon 45 45 W 14 577 2040 0 Blue 0
8 AM Mon 45 45 W 14 577 2040 0 Blue 0
9 AM Mon 46 46 W 14 577 2040 0 Blue 0
10 AM Mon 48 48 W 14 1274 2040 0 Blue 0
11 AM Mon 50 51 S 13 2439 2040 0 Blue 3
12 Noon Mon 52 53 S 13 2843 2060 20 Blue 5
1 PM Mon 52 53 S 13 2843 2060 20 Blue 5
2 PM Mon 53 54 S 13 2973 2423 383 Blue 6
3 PM Mon 53 54 S 13 2973 2423 383 Blue 6
4 PM Mon 53 53 S 13 2843 2060 20 Blue 5
5 PM Mon 52 52 S 10 2712 2040 0 Blue 4
6 PM Mon 51 51 S 10 2439 2040 0 Blue 3
7 PM Mon 49 49 S 10 1687 2040 0 Blue 1
8 PM Mon 47 47 S 10 577 2040 0 Blue 0
9 PM Mon 47 47 S 10 577 2040 0 Blue 0
10 PM Mon 46 46 S 10 577 2040 0 Blue 0
11 PM Mon 46 46 S 10 577 2040 0 Blue 0
12 Midnight Tue 45 45 S 10 577 2040 0 Blue 0
1 AM Tue 45 45 S 10 577 2040 0 Blue 0
2 AM Tue 45 45 S 10 577 2040 0 Blue 0
3 AM Tue 45 45 S 10 577 2040 0 Blue 0
4 AM Tue 44 44 S 10 577 2040 0 Blue 0
5 AM Tue 44 44 S 9 577 2040 0 Blue 0
6 AM Tue 44 44 S 9 577 2040 0 Blue 0
7 AM Tue 44 44 S 9 577 2040 0 Blue 0
8 AM Tue 44 44 S 9 577 2040 0 Blue 0
9 AM Tue 45 45 S 9 577 2040 0 Blue 0
10 AM Tue 47 48 S 9 1274 2040 0 Blue 0
11 AM Tue 49 50 S 14 2072 2040 0 Blue 2
12 Noon Tue 51 52 S 14 2712 2040 0 Blue 4
1 PM Tue 52 54 S 14 2973 2423 383 Blue 6
2 PM Tue 52 53 S 14 2843 2060 20 Blue 5
3 PM Tue 52 53 S 14 2843 2060 20 Blue 5
4 PM Tue 52 53 S 14 2843 2060 20 Blue 5
5 PM Tue 52 52 S 15 2712 2040 0 Blue 4
6 PM Tue 51 51 S 15 2439 2040 0 Blue 3
7 PM Tue 49 49 S 15 1687 2040 0 Blue 1
8 PM Tue 48 48 S 15 1274 2040 0 Blue 0
9 PM Tue 47 47 S 15 577 2040 0 Blue 0
10 PM Tue 47 47 S 15 577 2040 0 Blue 0
11 PM Tue 46 46 S 18 577 2040 0 Blue 0
12 Midnight Wed 46 46 S 18 577 2040 0 Blue 0
1 AM Wed 46 46 S 18 577 2040 0 Blue 0
2 AM Wed 46 46 S 18 577 2040 0 Blue 0
3 AM Wed 45 45 S 18 577 2040 0 Blue 0
4 AM Wed 45 45 S 18 577 2040 0 Blue 0
5 AM Wed 45 45 S 18 577 2040 0 Blue 0
6 AM Wed 45 45 S 18 577 2040 0 Blue 0
7 AM Wed 44 44 S 18 577 2040 0 Blue 0
8 AM Wed 44 44 S 18 577 2040 0 Blue 0
9 AM Wed 45 45 S 18 577 2040 0 Blue 0
10 AM Wed 47 47 S 18 577 2040 0 Blue 0
11 AM Wed 49 50 SW 21 2072 2040 0 Blue 2
12 Noon Wed 50 52 SW 21 2712 2040 0 Blue 4
1 PM Wed 51 53 SW 21 2843 2060 20 Blue 5
2 PM Wed 51 53 SW 21 2843 2060 20 Blue 5
3 PM Wed 51 52 SW 21 2712 2040 0 Blue 4
4 PM Wed 51 52 SW 21 2712 2040 0 Blue 4
5 PM Wed 51 51 W 21 2439 2040 0 Blue 3
6 PM Wed 50 50 W 21 2072 2040 0 Blue 2
7 PM Wed 48 48 W 21 1274 2040 0 Blue 0
8 PM Wed 47 47 W 21 577 2040 0 Blue 0
9 PM Wed 46 46 W 21 577 2040 0 Blue 0
10 PM Wed 46 46 W 21 577 2040 0 Blue 0
11 PM Wed 45 45 W 17 577 2040 0 Blue 0
12 Midnight Thu 45 45 W 17 577 2040 0 Blue 0
1 AM Thu 45 45 W 17 577 2040 0 Blue 0
2 AM Thu 45 45 W 17 577 2040 0 Blue 0
3 AM Thu 44 44 W 17 577 2040 0 Blue 0
4 AM Thu 44 44 W 17 577 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 website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the National Weather Service 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 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 ac_soaring@yahoo.com