Detailed Predictions for: Big Black
Launch Altitude (f): 3900
LZ Altitude (f): 1645
Sounding

Station:

 KNKX

Date/Time:

 1200Z 24 DEC 07

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)
12 Midnight Mon 46 46 NE 13 2674 3900 0 Blue 0
1 AM Mon 45 45 NE 9 2674 3900 0 Blue 0
2 AM Mon 45 45 NE 9 2674 3900 0 Blue 0
3 AM Mon 46 46 NE 9 2674 3900 0 Blue 0
4 AM Mon 46 46 NNE 6 2674 3900 0 Blue 0
5 AM Mon 45 45 NNE 6 2674 3900 0 Blue 0
6 AM Mon 45 45 NNE 6 2674 3900 0 Blue 0
7 AM Mon 47 47 N 5 2674 3900 0 Blue 0
8 AM Mon 52 52 N 5 2674 3900 0 Blue 0
9 AM Mon 60 60 N 5 3467 3900 0 Blue 0
10 AM Mon 62 63 ENE 3 4379 3900 0 Blue 0
11 AM Mon 64 66 ENE 3 5714 4370 470 Blue 1
12 Noon Mon 65 67 ENE 3 6240 4667 767 Blue 2
1 PM Mon 65 67 S 1 6240 4667 767 Blue 2
2 PM Mon 66 67 S 1 6240 4667 767 Blue 2
3 PM Mon 65 65 S 1 4977 4071 171 Blue 0
4 PM Mon 59 59 NE 5 3158 3900 0 Blue 0
5 PM Mon 50 50 NE 5 2674 3900 0 Blue 0
6 PM Mon 48 48 NE 5 2674 3900 0 Blue 0
7 PM Mon 48 48 ENE 18 2674 3900 0 Blue 0
8 PM Mon 47 47 ENE 18 2674 3900 0 Blue 0
9 PM Mon 46 46 ENE 18 2674 3900 0 Blue 0
10 PM Mon 46 46 NE 13 2674 3900 0 Blue 0
11 PM Mon 46 46 NE 13 2674 3900 0 Blue 0
12 Midnight Tue 43 43 NE 13 2674 3900 0 Blue 0
1 AM Tue 43 43 NE 18 2674 3900 0 Blue 0
2 AM Tue 42 42 NE 18 2674 3900 0 Blue 0
3 AM Tue 43 43 NE 18 2674 3900 0 Blue 0
4 AM Tue 43 43 NE 21 2674 3900 0 Blue 0
5 AM Tue 42 42 NE 21 2674 3900 0 Blue 0
6 AM Tue 42 42 NE 21 2674 3900 0 Blue 0
7 AM Tue 43 43 NE 26 2674 3900 0 Blue 0
8 AM Tue 48 48 NE 26 2674 3900 0 Blue 0
9 AM Tue 53 54 NE 26 2674 3900 0 Blue 0
10 AM Tue 55 56 ENE 29 2674 3900 0 Blue 0
11 AM Tue 56 58 ENE 29 2847 3900 0 Blue 0
12 Noon Tue 58 60 ENE 29 3467 3900 0 Blue 0
1 PM Tue 57 59 ENE 21 3158 3900 0 Blue 0
2 PM Tue 58 59 ENE 21 3158 3900 0 Blue 0
3 PM Tue 57 57 ENE 21 2674 3900 0 Blue 0
4 PM Tue 53 53 ENE 17 2674 3900 0 Blue 0
5 PM Tue 46 46 ENE 17 2674 3900 0 Blue 0
6 PM Tue 44 44 ENE 17 2674 3900 0 Blue 0
7 PM Tue 45 45 ENE 18 2674 3900 0 Blue 0
8 PM Tue 44 44 ENE 18 2674 3900 0 Blue 0
9 PM Tue 43 43 ENE 18 2674 3900 0 Blue 0
10 PM Tue 43 43 ENE 15 2674 3900 0 Blue 0
11 PM Tue 43 43 ENE 15 2674 3900 0 Blue 0
12 Midnight Wed 41 41 ENE 15 2674 3900 0 Blue 0
1 AM Wed 41 41 NNE 9 2674 3900 0 Blue 0
2 AM Wed 40 40 NNE 9 2674 3900 0 Blue 0
3 AM Wed 41 41 NNE 9 2674 3900 0 Blue 0
4 AM Wed 41 41 N 6 2674 3900 0 Blue 0
5 AM Wed 40 40 N 6 2674 3900 0 Blue 0
6 AM Wed 40 40 N 6 2674 3900 0 Blue 0
7 AM Wed 41 41 NW 4 2674 3900 0 Blue 0
8 AM Wed 45 45 NW 4 2674 3900 0 Blue 0
9 AM Wed 49 49 NW 4 2674 3900 0 Blue 0
10 AM Wed 51 52 WSW 6 2674 3900 0 Blue 0
11 AM Wed 52 54 WSW 6 2674 3900 0 Blue 0
12 Noon Wed 53 55 WSW 6 2674 3900 0 Blue 0
1 PM Wed 52 53 WSW 9 2674 3900 0 Blue 0
2 PM Wed 53 54 WSW 9 2674 3900 0 Blue 0
3 PM Wed 52 52 WSW 9 2674 3900 0 Blue 0
4 PM Wed 47 47 W 8 2674 3900 0 Blue 0
5 PM Wed 39 39 W 8 2674 3900 0 Blue 0
6 PM Wed 37 37 W 8 2674 3900 0 Blue 0
7 PM Wed 37 37 N 3 2674 3900 0 Blue 0
8 PM Wed 37 37 N 3 2674 3900 0 Blue 0
9 PM Wed 35 35 N 3 2674 3900 0 Blue 0
10 PM Wed 36 36 NNE 5 2674 3900 0 Blue 0
11 PM Wed 35 35 NNE 5 2674 3900 0 Blue 0
12 Midnight Thu 33 33 NNE 5 2674 3900 0 Blue 0
1 AM Thu 33 33 NE 7 2674 3900 0 Blue 0
2 AM Thu 32 32 NE 7 2674 3900 0 Blue 0
3 AM Thu 33 33 NE 7 2674 3900 0 Blue 0
4 AM Thu 33 33 NE 7 2674 3900 0 Blue 0
5 AM Thu 32 32 NE 7 2674 3900 0 Blue 0
6 AM Thu 32 32 NE 7 2674 3900 0 Blue 0
7 AM Thu 33 33 NE 7 2674 3900 0 Blue 0
8 AM Thu 37 37 NE 7 2674 3900 0 Blue 0
9 AM Thu 43 43 NE 7 2674 3900 0 Blue 0
10 AM Thu 44 45 ENE 11 2674 3900 0 Blue 0
11 AM Thu 45 47 ENE 11 2674 3900 0 Blue 0
12 Noon Thu 47 49 ENE 11 2674 3900 0 Blue 0
1 PM Thu 46 47 ENE 11 2674 3900 0 Blue 0
2 PM Thu 47 48 ENE 11 2674 3900 0 Blue 0
3 PM Thu 46 46 ENE 11 2674 3900 0 Blue 0
4 PM Thu 43 43 ENE 11 2674 3900 0 Blue 0
5 PM Thu 37 37 ENE 11 2674 3900 0 Blue 0
6 PM Thu 36 36 ENE 11 2674 3900 0 Blue 0
7 PM Thu 36 36 ENE 11 2674 3900 0 Blue 0
8 PM Thu 35 35 ENE 11 2674 3900 0 Blue 0
9 PM Thu 34 34 ENE 11 2674 3900 0 Blue 0
10 PM Thu 35 35 SSE 6 2674 3900 0 Blue 0
11 PM Thu 34 34 SSE 6 2674 3900 0 Blue 0
12 Midnight Fri 33 33 SSE 6 2674 3900 0 Blue 0
1 AM Fri 33 33 SSE 6 2674 3900 0 Blue 0
2 AM Fri 32 32 SSE 6 2674 3900 0 Blue 0
3 AM Fri 33 33 SSE 6 2674 3900 0 Blue 0
4 AM Fri 32 32 SSE 6 2674 3900 0 Blue 0
5 AM Fri 32 32 SSE 6 2674 3900 0 Blue 0
6 AM Fri 32 32 SSE 6 2674 3900 0 Blue 0
7 AM Fri 34 34 SSE 6 2674 3900 0 Blue 0
8 AM Fri 38 38 SSE 6 2674 3900 0 Blue 0
9 AM Fri 45 45 SSE 6 2674 3900 0 Blue 0
10 AM Fri 47 48 WSW 8 2674 3900 0 Blue 0
11 AM Fri 48 49 WSW 8 2674 3900 0 Blue 0
12 Noon Fri 50 51 WSW 8 2674 3900 0 Blue 0
1 PM Fri 49 50 WSW 8 2674 3900 0 Blue 0
2 PM Fri 50 50 WSW 8 2674 3900 0 Blue 0
3 PM Fri 49 49 WSW 8 2674 3900 0 Blue 0
4 PM Fri 46 46 WSW 8 2674 3900 0 Blue 0
5 PM Fri 40 40 WSW 8 2674 3900 0 Blue 0
6 PM Fri 39 39 WSW 8 2674 3900 0 Blue 0
7 PM Fri 40 40 WSW 8 2674 3900 0 Blue 0
8 PM Fri 39 39 WSW 8 2674 3900 0 Blue 0
9 PM Fri 38 38 WSW 8 2674 3900 0 Blue 0
10 PM Fri 39 39 WNW 3 2674 3900 0 Blue 0
11 PM Fri 38 38 WNW 3 2674 3900 0 Blue 0
12 Midnight Sat 37 37 WNW 3 2674 3900 0 Blue 0
1 AM Sat 37 37 WNW 3 2674 3900 0 Blue 0
2 AM Sat 36 36 WNW 3 2674 3900 0 Blue 0
3 AM Sat 37 37 WNW 3 2674 3900 0 Blue 0
4 AM Sat 36 36 WNW 3 2674 3900 0 Blue 0
5 AM Sat 36 36 WNW 3 2674 3900 0 Blue 0
6 AM Sat 36 36 WNW 3 2674 3900 0 Blue 0
7 AM Sat 37 37 WNW 3 2674 3900 0 Blue 0
8 AM Sat 42 42 WNW 3 2674 3900 0 Blue 0
9 AM Sat 47 47 WNW 3 2674 3900 0 Blue 0
10 AM Sat 49 50 W 9 2674 3900 0 Blue 0
11 AM Sat 50 51 W 9 2674 3900 0 Blue 0
12 Noon Sat 52 53 W 9 2674 3900 0 Blue 0
1 PM Sat 51 52 W 9 2674 3900 0 Blue 0
2 PM Sat 52 53 W 9 2674 3900 0 Blue 0
3 PM Sat 51 51 W 9 2674 3900 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 Weather Channel website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the Weather Channel 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 Weather Channel 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 (tadh@flytorrey.com)