Detailed Predictions for: Dunlap
Launch Altitude (f): 4460
LZ Altitude (f): 1950
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 62 62 N 8 1562 4460 0 Blue 0
6 AM Fri 63 63 N 8 1562 4460 0 Blue 0
7 AM Fri 66 66 N 8 1562 4460 0 Blue 0
8 AM Fri 71 71 NE 3 1955 4460 0 Blue 0
9 AM Fri 78 80 NE 3 2879 4460 0 Blue 1
10 AM Fri 86 89 NE 3 5553 4662 202 Blue 10
11 AM Fri 92 97 SW 9 9950 7735 3275 Blue 18
12 Noon Fri 95 102 SW 9 13022 13022 8562 White 23
1 PM Fri 97 104 SW 9 13430 13430 8970 White 25
2 PM Fri 98 105 W 10 13635 13635 9175 White 26
3 PM Fri 99 104 W 10 13430 13430 8970 White 25
4 PM Fri 99 103 W 10 13226 13226 8766 White 24
5 PM Fri 97 99 W 7 12405 9146 4686 White 20
6 PM Fri 93 93 W 7 7244 5939 1479 Blue 14
7 PM Fri 87 87 W 7 4824 4460 0 Blue 8
8 PM Fri 81 81 N 3 3175 4460 0 Blue 2
9 PM Fri 77 77 N 3 2475 4460 0 Blue 0
10 PM Fri 75 75 N 3 2301 4460 0 Blue 0
11 PM Fri 72 72 NE 12 2042 4460 0 Blue 0
12 Midnight Sat 70 70 NE 12 1869 4460 0 Blue 0
1 AM Sat 69 69 NE 12 1783 4460 0 Blue 0
2 AM Sat 68 68 N 12 1696 4460 0 Blue 0
3 AM Sat 66 66 N 12 1562 4460 0 Blue 0
4 AM Sat 65 65 N 12 1562 4460 0 Blue 0
5 AM Sat 65 65 N 10 1562 4460 0 Blue 0
6 AM Sat 66 66 N 10 1562 4460 0 Blue 0
7 AM Sat 68 68 N 10 1696 4460 0 Blue 0
8 AM Sat 71 71 NE 6 1955 4460 0 Blue 0
9 AM Sat 78 80 NE 6 2879 4460 0 Blue 1
10 AM Sat 85 88 NE 6 5111 4460 0 Blue 9
11 AM Sat 91 96 SW 8 9292 7182 2722 Blue 17
12 Noon Sat 94 101 SW 8 12816 10419 5959 White 22
1 PM Sat 96 103 SW 8 13226 13226 8766 White 24
2 PM Sat 96 103 W 10 13226 13226 8766 White 24
3 PM Sat 98 103 W 10 13226 13226 8766 White 24
4 PM Sat 98 102 W 10 13022 13022 8562 White 23
5 PM Sat 96 98 W 8 12199 8461 4001 White 19
6 PM Sat 92 92 W 8 6832 5510 1050 Blue 13
7 PM Sat 87 87 W 8 4824 4460 0 Blue 8
8 PM Sat 81 81 N 8 3175 4460 0 Blue 2
9 PM Sat 77 77 N 8 2475 4460 0 Blue 0
10 PM Sat 74 74 N 8 2215 4460 0 Blue 0
11 PM Sat 72 72 NE 9 2042 4460 0 Blue 0
12 Midnight Sun 70 70 NE 9 1869 4460 0 Blue 0
1 AM Sun 70 70 NE 9 1869 4460 0 Blue 0
2 AM Sun 69 69 N 9 1783 4460 0 Blue 0
3 AM Sun 68 68 N 9 1696 4460 0 Blue 0
4 AM Sun 67 67 N 9 1610 4460 0 Blue 0
5 AM Sun 67 67 NE 10 1610 4460 0 Blue 0
6 AM Sun 67 67 NE 10 1610 4460 0 Blue 0
7 AM Sun 68 68 NE 10 1696 4460 0 Blue 0
8 AM Sun 70 70 NE 10 1869 4460 0 Blue 0
9 AM Sun 75 77 NE 10 2475 4460 0 Blue 0
10 AM Sun 81 84 NE 10 4137 4460 0 Blue 5
11 AM Sun 85 90 SW 9 5987 4813 353 Blue 11
12 Noon Sun 88 95 SW 9 8599 6774 2314 Blue 16
1 PM Sun 90 97 SW 9 9950 7735 3275 Blue 18
2 PM Sun 91 98 SW 9 12199 8461 4001 White 19
3 PM Sun 92 97 SW 9 9950 7735 3275 Blue 18
4 PM Sun 92 96 SW 9 9292 7182 2722 Blue 17
5 PM Sun 90 92 W 10 6832 5510 1050 Blue 13
6 PM Sun 85 85 W 10 4453 4460 0 Blue 6
7 PM Sun 79 79 W 10 2696 4460 0 Blue 0
8 PM Sun 73 73 W 10 2128 4460 0 Blue 0
9 PM Sun 69 69 W 10 1783 4460 0 Blue 0
10 PM Sun 66 66 W 10 1562 4460 0 Blue 0
11 PM Sun 64 64 E 9 1562 4460 0 Blue 0
12 Midnight Mon 62 62 E 9 1562 4460 0 Blue 0
1 AM Mon 61 61 E 9 1562 4460 0 Blue 0
2 AM Mon 60 60 E 9 1562 4460 0 Blue 0
3 AM Mon 58 58 E 9 1562 4460 0 Blue 0
4 AM Mon 57 57 E 9 1562 4460 0 Blue 0
5 AM Mon 57 57 E 10 1562 4460 0 Blue 0
6 AM Mon 58 58 E 10 1562 4460 0 Blue 0
7 AM Mon 60 60 E 10 1562 4460 0 Blue 0
8 AM Mon 63 63 E 10 1562 4460 0 Blue 0
9 AM Mon 68 70 E 10 1869 4460 0 Blue 0
10 AM Mon 74 77 E 10 2475 4460 0 Blue 0
11 AM Mon 80 85 SW 8 4453 4460 0 Blue 6
12 Noon Mon 83 90 SW 8 5987 4813 353 Blue 11
1 PM Mon 85 92 SW 8 6832 5510 1050 Blue 13
2 PM Mon 86 93 SW 8 7244 5939 1479 Blue 14
3 PM Mon 88 93 SW 8 7244 5939 1479 Blue 14
4 PM Mon 89 93 SW 8 7244 5939 1479 Blue 14
5 PM Mon 88 90 W 7 5987 4813 353 Blue 11
6 PM Mon 83 83 W 7 3819 4460 0 Blue 4
7 PM Mon 77 77 W 7 2475 4460 0 Blue 0
8 PM Mon 71 71 W 7 1955 4460 0 Blue 0
9 PM Mon 68 68 W 7 1696 4460 0 Blue 0
10 PM Mon 67 67 W 7 1610 4460 0 Blue 0
11 PM Mon 65 65 E 10 1562 4460 0 Blue 0
12 Midnight Tue 63 63 E 10 1562 4460 0 Blue 0
1 AM Tue 62 62 E 10 1562 4460 0 Blue 0
2 AM Tue 60 60 E 10 1562 4460 0 Blue 0
3 AM Tue 59 59 E 10 1562 4460 0 Blue 0
4 AM Tue 58 58 E 10 1562 4460 0 Blue 0
5 AM Tue 58 58 E 10 1562 4460 0 Blue 0
6 AM Tue 58 58 E 10 1562 4460 0 Blue 0
7 AM Tue 60 60 E 10 1562 4460 0 Blue 0
8 AM Tue 63 63 E 10 1562 4460 0 Blue 0
9 AM Tue 68 70 E 10 1869 4460 0 Blue 0
10 AM Tue 74 77 E 10 2475 4460 0 Blue 0
11 AM Tue 79 84 SW 10 4137 4460 0 Blue 5
12 Noon Tue 81 88 SW 10 5111 4460 0 Blue 9
1 PM Tue 83 90 SW 10 5987 4813 353 Blue 11
2 PM Tue 83 90 SW 10 5987 4813 353 Blue 11
3 PM Tue 85 90 SW 10 5987 4813 353 Blue 11
4 PM Tue 85 89 SW 10 5553 4662 202 Blue 10
5 PM Tue 84 86 SW 9 4672 4460 0 Blue 7
6 PM Tue 80 80 SW 9 2879 4460 0 Blue 1
7 PM Tue 75 75 SW 9 2301 4460 0 Blue 0
8 PM Tue 70 70 SW 9 1869 4460 0 Blue 0
9 PM Tue 67 67 SW 9 1610 4460 0 Blue 0
10 PM Tue 65 65 SW 9 1562 4460 0 Blue 0
11 PM Tue 64 64 SE 5 1562 4460 0 Blue 0
12 Midnight Wed 62 62 SE 5 1562 4460 0 Blue 0
1 AM Wed 60 60 SE 5 1562 4460 0 Blue 0
2 AM Wed 59 59 SE 5 1562 4460 0 Blue 0
3 AM Wed 58 58 SE 5 1562 4460 0 Blue 0
4 AM Wed 56 56 SE 5 1562 4460 0 Blue 0
5 AM Wed 56 56 SE 3 1562 4460 0 Blue 0
6 AM Wed 56 56 SE 3 1562 4460 0 Blue 0
7 AM Wed 57 57 SE 3 1562 4460 0 Blue 0
8 AM Wed 60 60 SE 3 1562 4460 0 Blue 0
9 AM Wed 64 66 SE 3 1562 4460 0 Blue 0
10 AM Wed 68 71 SE 3 1955 4460 0 Blue 0
11 AM Wed 73 78 SW 9 2561 4460 0 Blue 0
12 Noon Wed 76 83 SW 9 3819 4460 0 Blue 4
1 PM Wed 78 85 SW 9 4453 4460 0 Blue 6
2 PM Wed 79 86 SW 9 4672 4460 0 Blue 7
3 PM Wed 80 85 SW 9 4453 4460 0 Blue 6
4 PM Wed 81 85 SW 9 4453 4460 0 Blue 6
5 PM Wed 80 82 W 10 3498 4460 0 Blue 3
6 PM Wed 76 76 W 10 2388 4460 0 Blue 0
7 PM Wed 71 71 W 10 1955 4460 0 Blue 0
8 PM Wed 66 66 W 10 1562 4460 0 Blue 0
9 PM Wed 64 64 W 10 1562 4460 0 Blue 0
10 PM Wed 63 63 W 10 1562 4460 0 Blue 0
11 PM Wed 62 62 NE 3 1562 4460 0 Blue 0
12 Midnight Thu 60 60 NE 3 1562 4460 0 Blue 0
1 AM Thu 58 58 NE 3 1562 4460 0 Blue 0
2 AM Thu 56 56 NE 3 1562 4460 0 Blue 0
3 AM Thu 55 55 NE 3 1562 4460 0 Blue 0
4 AM Thu 54 54 NE 3 1562 4460 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