Detailed Predictions for: Mt Diablo
Launch Altitude (f): 3000
LZ Altitude (f): 1000
Sounding

Station:

 KOAK

Date/Time:

 3 SEP 2010

Temp/Wind data from:

NOAA Digital Forecast

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 73 73 SW 5 2605 3000 0 Blue 0
6 AM Fri 73 73 SW 5 2605 3000 0 Blue 0
7 AM Fri 72 72 SW 5 2605 3000 0 Blue 0
8 AM Fri 75 75 SW 7 2605 3000 0 Blue 0
9 AM Fri 79 80 SW 7 3603 3000 0 Blue 2
10 AM Fri 81 84 SW 7 4725 3914 914 Blue 6
11 AM Fri 82 87 W 9 5713 4716 1716 Blue 9
12 Noon Fri 84 90 W 9 6993 5675 2675 Blue 12
1 PM Fri 86 93 W 9 8891 6939 3939 Blue 15
2 PM Fri 87 93 W 13 8891 6939 3939 Blue 15
3 PM Fri 88 93 W 13 8891 6939 3939 Blue 15
4 PM Fri 88 92 W 13 8167 6525 3525 Blue 14
5 PM Fri 83 85 W 13 4878 4230 1230 Blue 7
6 PM Fri 82 83 W 13 4561 3595 595 Blue 5
7 PM Fri 79 79 W 13 3278 3000 0 Blue 1
8 PM Fri 76 76 W 12 2605 3000 0 Blue 0
9 PM Fri 75 75 W 12 2605 3000 0 Blue 0
10 PM Fri 75 75 W 12 2605 3000 0 Blue 0
11 PM Fri 74 74 W 9 2605 3000 0 Blue 0
12 Midnight Sat 73 73 W 9 2605 3000 0 Blue 0
1 AM Sat 73 73 W 9 2605 3000 0 Blue 0
2 AM Sat 72 72 W 9 2605 3000 0 Blue 0
3 AM Sat 71 71 W 9 2605 3000 0 Blue 0
4 AM Sat 70 70 W 9 2605 3000 0 Blue 0
5 AM Sat 69 69 W 9 2605 3000 0 Blue 0
6 AM Sat 68 68 W 9 2605 3000 0 Blue 0
7 AM Sat 68 68 W 9 2605 3000 0 Blue 0
8 AM Sat 71 71 W 12 2605 3000 0 Blue 0
9 AM Sat 75 76 W 12 2605 3000 0 Blue 0
10 AM Sat 77 80 W 12 3603 3000 0 Blue 2
11 AM Sat 78 83 W 14 4561 3595 595 Blue 5
12 Noon Sat 80 86 W 14 5272 4544 1544 Blue 8
1 PM Sat 82 89 W 14 6574 5238 2238 Blue 11
2 PM Sat 83 89 W 12 6574 5238 2238 Blue 11
3 PM Sat 85 90 W 12 6993 5675 2675 Blue 12
4 PM Sat 85 89 W 12 6574 5238 2238 Blue 11
5 PM Sat 80 82 W 14 4244 3273 273 Blue 4
6 PM Sat 78 78 W 14 2950 3000 0 Blue 0
7 PM Sat 75 75 W 14 2605 3000 0 Blue 0
8 PM Sat 72 72 W 14 2605 3000 0 Blue 0
9 PM Sat 70 70 W 14 2605 3000 0 Blue 0
10 PM Sat 70 70 W 14 2605 3000 0 Blue 0
11 PM Sat 69 69 W 15 2605 3000 0 Blue 0
12 Midnight Sun 69 69 W 15 2605 3000 0 Blue 0
1 AM Sun 68 68 W 15 2605 3000 0 Blue 0
2 AM Sun 67 67 W 15 2605 3000 0 Blue 0
3 AM Sun 67 67 W 15 2605 3000 0 Blue 0
4 AM Sun 65 65 W 15 2605 3000 0 Blue 0
5 AM Sun 64 64 NW 10 2605 3000 0 Blue 0
6 AM Sun 63 63 NW 10 2605 3000 0 Blue 0
7 AM Sun 63 63 NW 10 2605 3000 0 Blue 0
8 AM Sun 66 66 NW 10 2605 3000 0 Blue 0
9 AM Sun 69 70 NW 10 2605 3000 0 Blue 0
10 AM Sun 71 74 NW 10 2605 3000 0 Blue 0
11 AM Sun 72 77 N 10 2752 3000 0 Blue 0
12 Noon Sun 74 80 N 10 3603 3000 0 Blue 2
1 PM Sun 76 83 N 10 4561 3595 595 Blue 5
2 PM Sun 77 83 N 10 4561 3595 595 Blue 5
3 PM Sun 78 83 N 10 4561 3595 595 Blue 5
4 PM Sun 79 83 N 10 4561 3595 595 Blue 5
5 PM Sun 74 76 NW 12 2605 3000 0 Blue 0
6 PM Sun 73 73 NW 12 2605 3000 0 Blue 0
7 PM Sun 71 71 NW 12 2605 3000 0 Blue 0
8 PM Sun 68 68 NW 12 2605 3000 0 Blue 0
9 PM Sun 67 67 NW 12 2605 3000 0 Blue 0
10 PM Sun 67 67 NW 12 2605 3000 0 Blue 0
11 PM Sun 66 66 N 18 2605 3000 0 Blue 0
12 Midnight Mon 66 66 N 18 2605 3000 0 Blue 0
1 AM Mon 66 66 N 18 2605 3000 0 Blue 0
2 AM Mon 65 65 N 18 2605 3000 0 Blue 0
3 AM Mon 64 64 N 18 2605 3000 0 Blue 0
4 AM Mon 63 63 N 18 2605 3000 0 Blue 0
5 AM Mon 62 62 N 17 2605 3000 0 Blue 0
6 AM Mon 62 62 N 17 2605 3000 0 Blue 0
7 AM Mon 61 61 N 17 2605 3000 0 Blue 0
8 AM Mon 65 65 N 17 2605 3000 0 Blue 0
9 AM Mon 69 70 N 17 2605 3000 0 Blue 0
10 AM Mon 72 75 N 17 2605 3000 0 Blue 0
11 AM Mon 73 78 NE 9 2950 3000 0 Blue 0
12 Noon Mon 76 82 NE 9 4244 3273 273 Blue 4
1 PM Mon 78 84 NE 9 4725 3914 914 Blue 6
2 PM Mon 79 85 NE 9 4878 4230 1230 Blue 7
3 PM Mon 81 86 NE 9 5272 4544 1544 Blue 8
4 PM Mon 81 85 NE 9 4878 4230 1230 Blue 7
5 PM Mon 77 79 W 9 3278 3000 0 Blue 1
6 PM Mon 76 76 W 9 2605 3000 0 Blue 0
7 PM Mon 73 73 W 9 2605 3000 0 Blue 0
8 PM Mon 70 70 W 9 2605 3000 0 Blue 0
9 PM Mon 69 69 W 9 2605 3000 0 Blue 0
10 PM Mon 69 69 W 9 2605 3000 0 Blue 0
11 PM Mon 69 69 SW 8 2605 3000 0 Blue 0
12 Midnight Tue 68 68 SW 8 2605 3000 0 Blue 0
1 AM Tue 68 68 SW 8 2605 3000 0 Blue 0
2 AM Tue 67 67 SW 8 2605 3000 0 Blue 0
3 AM Tue 66 66 SW 8 2605 3000 0 Blue 0
4 AM Tue 66 66 SW 8 2605 3000 0 Blue 0
5 AM Tue 65 65 S 7 2605 3000 0 Blue 0
6 AM Tue 64 64 S 7 2605 3000 0 Blue 0
7 AM Tue 63 63 S 7 2605 3000 0 Blue 0
8 AM Tue 65 65 S 7 2605 3000 0 Blue 0
9 AM Tue 67 68 S 7 2605 3000 0 Blue 0
10 AM Tue 68 71 S 7 2605 3000 0 Blue 0
11 AM Tue 69 74 SW 8 2605 3000 0 Blue 0
12 Noon Tue 70 76 SW 8 2605 3000 0 Blue 0
1 PM Tue 71 78 SW 8 2950 3000 0 Blue 0
2 PM Tue 72 78 SW 8 2950 3000 0 Blue 0
3 PM Tue 72 77 SW 8 2752 3000 0 Blue 0
4 PM Tue 72 76 SW 8 2605 3000 0 Blue 0
5 PM Tue 68 70 W 20 2605 3000 0 Blue 0
6 PM Tue 66 66 W 20 2605 3000 0 Blue 0
7 PM Tue 64 64 W 20 2605 3000 0 Blue 0
8 PM Tue 61 61 W 20 2605 3000 0 Blue 0
9 PM Tue 60 60 W 20 2605 3000 0 Blue 0
10 PM Tue 60 60 W 20 2605 3000 0 Blue 0
11 PM Tue 59 59 W 18 2605 3000 0 Blue 0
12 Midnight Wed 59 59 W 18 2605 3000 0 Blue 0
1 AM Wed 58 58 W 18 2605 3000 0 Blue 0
2 AM Wed 57 57 W 18 2605 3000 0 Blue 0
3 AM Wed 57 57 W 18 2605 3000 0 Blue 0
4 AM Wed 56 56 W 18 2605 3000 0 Blue 0
5 AM Wed 55 55 W 13 2605 3000 0 Blue 0
6 AM Wed 54 54 W 13 2605 3000 0 Blue 0
7 AM Wed 53 53 W 13 2605 3000 0 Blue 0
8 AM Wed 56 56 W 13 2605 3000 0 Blue 0
9 AM Wed 60 61 W 13 2605 3000 0 Blue 0
10 AM Wed 62 65 W 13 2605 3000 0 Blue 0
11 AM Wed 62 65 W 8 2605 3000 0 Blue 0
12 Noon Wed 64 68 W 8 2605 3000 0 Blue 0
1 PM Wed 66 70 W 8 2605 3000 0 Blue 0
2 PM Wed 67 71 W 8 2605 3000 0 Blue 0
3 PM Wed 68 71 W 8 2605 3000 0 Blue 0
4 PM Wed 68 70 W 8 2605 3000 0 Blue 0
5 PM Wed 65 66 W 9 2605 3000 0 Blue 0
6 PM Wed 64 64 W 9 2605 3000 0 Blue 0
7 PM Wed 63 63 W 9 2605 3000 0 Blue 0
8 PM Wed 60 60 W 9 2605 3000 0 Blue 0
9 PM Wed 59 59 W 9 2605 3000 0 Blue 0
10 PM Wed 60 60 W 9 2605 3000 0 Blue 0
11 PM Wed 59 59 NW 8 2605 3000 0 Blue 0
12 Midnight Thu 59 59 NW 8 2605 3000 0 Blue 0
1 AM Thu 59 59 NW 8 2605 3000 0 Blue 0
2 AM Thu 58 58 NW 8 2605 3000 0 Blue 0
3 AM Thu 57 57 NW 8 2605 3000 0 Blue 0
4 AM Thu 57 57 NW 8 2605 3000 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