Detailed Predictions for: Blossom Valley
Launch Altitude (f): 1500
LZ Altitude (f): 700
Sounding

Station:

KNKX

Date/Time:

23 SEP 2017

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 Sat 54 54 E 3 525 1500 0 Blue 0
6 AM Sat 54 54 E 5 525 1500 0 Blue 0
7 AM Sat 54 54 E 5 525 1500 0 Blue 0
8 AM Sat 56 56 SE 3 525 1500 0 Blue 0
9 AM Sat 58 58 S 2 525 1500 0 Blue 0
10 AM Sat 61 62 S 2 525 1500 0 Blue 0
11 AM Sat 64 67 W 7 3254 1500 0 Blue 3
12 Noon Sat 67 71 W 7 4727 3586 2086 White 7
1 PM Sat 69 73 W 8 5159 4521 3021 White 9
2 PM Sat 71 74 W 13 5373 4867 3367 White 10
3 PM Sat 71 74 W 13 5373 4867 3367 White 10
4 PM Sat 71 72 W 12 4944 4294 2794 White 8
5 PM Sat 69 69 W 9 4287 2905 1405 White 5
6 PM Sat 66 66 W 9 3143 1500 0 Blue 2
7 PM Sat 62 62 W 9 525 1500 0 Blue 0
8 PM Sat 60 60 NW 5 525 1500 0 Blue 0
9 PM Sat 58 58 N 5 525 1500 0 Blue 0
10 PM Sat 57 57 N 3 525 1500 0 Blue 0
11 PM Sat 57 57 NE 7 525 1500 0 Blue 0
12 Midnight Sun 56 56 NE 7 525 1500 0 Blue 0
1 AM Sun 57 57 NE 7 525 1500 0 Blue 0
2 AM Sun 56 56 NE 5 525 1500 0 Blue 0
3 AM Sun 56 56 NE 3 525 1500 0 Blue 0
4 AM Sun 56 56 NE 3 525 1500 0 Blue 0
5 AM Sun 56 56 S 2 525 1500 0 Blue 0
6 AM Sun 56 56 SE 2 525 1500 0 Blue 0
7 AM Sun 56 56 SE 2 525 1500 0 Blue 0
8 AM Sun 59 59 SW 2 525 1500 0 Blue 0
9 AM Sun 63 65 W 2 2738 1500 0 Blue 1
10 AM Sun 67 70 W 2 4502 3246 1746 White 6
11 AM Sun 71 76 W 8 5797 5153 3653 White 12
12 Noon Sun 75 81 W 8 6852 6852 5352 White 17
1 PM Sun 78 84 W 8 7481 7481 5981 White 20
2 PM Sun 80 85 W 14 7690 7690 6190 White 21
3 PM Sun 81 85 W 14 7690 7690 6190 White 21
4 PM Sun 80 82 W 14 7061 7061 5561 White 18
5 PM Sun 77 78 W 14 6219 5757 4257 White 14
6 PM Sun 74 74 NW 13 5373 4867 3367 White 10
7 PM Sun 68 68 NW 12 3601 2727 1227 Blue 4
8 PM Sun 64 64 N 3 525 1500 0 Blue 0
9 PM Sun 61 61 N 3 525 1500 0 Blue 0
10 PM Sun 60 60 NE 3 525 1500 0 Blue 0
11 PM Sun 59 59 E 5 525 1500 0 Blue 0
12 Midnight Mon 59 59 E 6 525 1500 0 Blue 0
1 AM Mon 59 59 E 6 525 1500 0 Blue 0
2 AM Mon 59 59 E 3 525 1500 0 Blue 0
3 AM Mon 58 58 E 3 525 1500 0 Blue 0
4 AM Mon 58 58 E 5 525 1500 0 Blue 0
5 AM Mon 58 58 E 9 525 1500 0 Blue 0
6 AM Mon 58 58 E 9 525 1500 0 Blue 0
7 AM Mon 58 58 E 9 525 1500 0 Blue 0
8 AM Mon 61 61 NW 3 525 1500 0 Blue 0
9 AM Mon 65 66 NW 3 3143 1500 0 Blue 2
10 AM Mon 69 72 NW 3 4944 4294 2794 White 8
11 AM Mon 74 79 W 10 6431 6130 4630 White 15
12 Noon Mon 78 84 W 10 7481 7481 5981 White 20
1 PM Mon 81 87 W 10 8106 8106 6606 White 23
2 PM Mon 84 89 W 13 8518 8518 7018 White 25
3 PM Mon 84 88 W 13 8313 8313 6813 White 24
4 PM Mon 83 85 W 13 7690 7690 6190 White 21
5 PM Mon 80 81 W 14 6852 6852 5352 White 17
6 PM Mon 76 76 W 14 5797 5153 3653 White 12
7 PM Mon 70 70 W 14 4502 3246 1746 White 6
8 PM Mon 66 66 NW 3 3143 1500 0 Blue 2
9 PM Mon 63 63 NW 3 525 1500 0 Blue 0
10 PM Mon 62 62 NW 3 525 1500 0 Blue 0
11 PM Mon 62 62 SE 2 525 1500 0 Blue 0
12 Midnight Tue 61 61 SE 2 525 1500 0 Blue 0
1 AM Tue 61 61 SE 2 525 1500 0 Blue 0
2 AM Tue 61 61 NE 8 525 1500 0 Blue 0
3 AM Tue 60 60 NE 8 525 1500 0 Blue 0
4 AM Tue 60 60 NE 8 525 1500 0 Blue 0
5 AM Tue 60 60 E 10 525 1500 0 Blue 0
6 AM Tue 60 60 E 10 525 1500 0 Blue 0
7 AM Tue 60 60 E 10 525 1500 0 Blue 0
8 AM Tue 63 63 E 10 525 1500 0 Blue 0
9 AM Tue 67 68 E 10 3601 2727 1227 Blue 4
10 AM Tue 72 75 E 10 5585 4982 3482 White 11
11 AM Tue 76 80 W 7 6641 6498 4998 White 16
12 Noon Tue 80 85 W 7 7690 7690 6190 White 21
1 PM Tue 84 90 W 7 8723 8723 7223 White 26
2 PM Tue 86 91 W 13 8927 8927 7427 White 27
3 PM Tue 88 92 W 13 9133 9133 7633 White 28
4 PM Tue 86 88 W 13 8313 8313 6813 White 24
5 PM Tue 83 84 W 13 7481 7481 5981 White 20
6 PM Tue 79 79 W 13 6431 6130 4630 White 15
7 PM Tue 72 72 W 13 4944 4294 2794 White 8
8 PM Tue 68 68 N 6 3601 2727 1227 Blue 4
9 PM Tue 66 66 N 6 3143 1500 0 Blue 2
10 PM Tue 64 64 N 6 525 1500 0 Blue 0
11 PM Tue 64 64 NE 8 525 1500 0 Blue 0
12 Midnight Wed 63 63 NE 8 525 1500 0 Blue 0
1 AM Wed 63 63 NE 8 525 1500 0 Blue 0
2 AM Wed 63 63 E 8 525 1500 0 Blue 0
3 AM Wed 62 62 E 8 525 1500 0 Blue 0
4 AM Wed 62 62 E 8 525 1500 0 Blue 0
5 AM Wed 62 62 E 9 525 1500 0 Blue 0
6 AM Wed 62 62 E 9 525 1500 0 Blue 0
7 AM Wed 62 62 E 9 525 1500 0 Blue 0
8 AM Wed 65 65 E 3 2738 1500 0 Blue 1
9 AM Wed 69 70 E 3 4502 3246 1746 White 6
10 AM Wed 74 77 E 3 6008 5379 3879 White 13
11 AM Wed 78 83 W 7 7271 7271 5771 White 19
12 Noon Wed 82 88 W 7 8313 8313 6813 White 24
1 PM Wed 86 92 W 7 9133 9133 7633 White 28
2 PM Wed 88 94 W 10 9545 9545 8045 White 30
3 PM Wed 90 94 W 10 9545 9545 8045 White 30
4 PM Wed 88 90 W 10 8723 8723 7223 White 26
5 PM Wed 85 86 W 13 7898 7898 6398 White 22
6 PM Wed 80 80 W 13 6641 6498 4998 White 16
7 PM Wed 74 74 W 13 5373 4867 3367 White 10
8 PM Wed 69 69 N 3 4287 2905 1405 White 5
9 PM Wed 67 67 N 3 3254 1500 0 Blue 3
10 PM Wed 65 65 N 3 2738 1500 0 Blue 1
11 PM Wed 65 65 NE 7 2738 1500 0 Blue 1
12 Midnight Thu 64 64 NE 7 525 1500 0 Blue 0
1 AM Thu 64 64 NE 7 525 1500 0 Blue 0
2 AM Thu 64 64 NE 5 525 1500 0 Blue 0
3 AM Thu 63 63 NE 5 525 1500 0 Blue 0
4 AM Thu 63 63 NE 5 525 1500 0 Blue 0
5 AM Thu 63 63 E 9 525 1500 0 Blue 0
6 AM Thu 63 63 E 9 525 1500 0 Blue 0
7 AM Thu 63 63 E 9 525 1500 0 Blue 0
8 AM Thu 66 66 NE 7 3143 1500 0 Blue 2
9 AM Thu 70 71 NE 7 4727 3586 2086 White 7
10 AM Thu 74 77 NE 7 6008 5379 3879 White 13
11 AM Thu 79 84 W 3 7481 7481 5981 White 20
12 Noon Thu 83 89 W 3 8518 8518 7018 White 25
1 PM Thu 86 92 W 3 9133 9133 7633 White 28
2 PM Thu 88 93 W 14 9339 9339 7839 White 29
3 PM Thu 90 94 W 14 9545 9545 8045 White 30
4 PM Thu 88 90 W 14 8723 8723 7223 White 26
5 PM Thu 85 86 NW 12 7898 7898 6398 White 22
6 PM Thu 82 82 NW 12 7061 7061 5561 White 18
7 PM Thu 76 76 NW 12 5797 5153 3653 White 12
8 PM Thu 72 72 N 5 4944 4294 2794 White 8
9 PM Thu 69 69 N 5 4287 2905 1405 White 5
10 PM Thu 68 68 N 5 3601 2727 1227 Blue 4
11 PM Thu 67 67 E 5 3254 1500 0 Blue 3
12 Midnight Fri 67 67 E 5 3254 1500 0 Blue 3
1 AM Fri 67 67 E 5 3254 1500 0 Blue 3
2 AM Fri 67 67 E 8 3254 1500 0 Blue 3
3 AM Fri 66 66 E 8 3143 1500 0 Blue 2
4 AM Fri 66 66 E 8 3143 1500 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 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