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

Station:

KNKX

Date/Time:

25 AUG 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 Sun 64 64 E 0 807 1500 0 Blue 0
6 AM Sun 65 65 E 1 807 1500 0 Blue 0
7 AM Sun 68 68 E 2 942 1500 0 Blue 0
8 AM Sun 72 72 SE 0 1214 1500 0 Blue 0
9 AM Sun 78 80 W 1 1669 1500 0 Blue 6
10 AM Sun 83 86 W 2 2473 2144 644 Blue 12
11 AM Sun 87 92 W 8 4281 3231 1731 Blue 18
12 Noon Sun 89 95 W 9 4932 4263 2763 Blue 21
1 PM Sun 90 96 W 10 5208 4440 2940 Blue 22
2 PM Sun 89 95 W 12 4932 4263 2763 Blue 21
3 PM Sun 90 95 W 12 4932 4263 2763 Blue 21
4 PM Sun 89 92 W 12 4281 3231 1731 Blue 18
5 PM Sun 87 88 W 10 3097 2305 805 Blue 14
6 PM Sun 83 83 W 9 2146 1667 167 Blue 9
7 PM Sun 79 79 W 8 1595 1500 0 Blue 5
8 PM Sun 75 75 W 3 1400 1500 0 Blue 1
9 PM Sun 73 73 W 2 1282 1500 0 Blue 0
10 PM Sun 72 72 W 2 1214 1500 0 Blue 0
11 PM Sun 71 71 SW 2 1146 1500 0 Blue 0
12 Midnight Mon 70 70 S 1 1078 1500 0 Blue 0
1 AM Mon 68 68 S 1 942 1500 0 Blue 0
2 AM Mon 67 67 SE 0 875 1500 0 Blue 0
3 AM Mon 66 66 S 0 807 1500 0 Blue 0
4 AM Mon 65 65 E 0 807 1500 0 Blue 0
5 AM Mon 65 65 S 0 807 1500 0 Blue 0
6 AM Mon 65 65 S 0 807 1500 0 Blue 0
7 AM Mon 67 67 S 1 875 1500 0 Blue 0
8 AM Mon 70 70 SW 1 1078 1500 0 Blue 0
9 AM Mon 74 75 SW 2 1400 1500 0 Blue 1
10 AM Mon 80 83 SW 3 2146 1667 167 Blue 9
11 AM Mon 84 88 W 8 3097 2305 805 Blue 14
12 Noon Mon 87 92 W 9 4281 3231 1731 Blue 18
1 PM Mon 89 95 W 10 4932 4263 2763 Blue 21
2 PM Mon 88 93 W 12 4465 3373 1873 Blue 19
3 PM Mon 88 92 W 12 4281 3231 1731 Blue 18
4 PM Mon 87 90 W 12 3383 2670 1170 Blue 16
5 PM Mon 85 86 W 10 2473 2144 644 Blue 12
6 PM Mon 82 82 W 9 2090 1594 94 Blue 8
7 PM Mon 79 79 W 8 1595 1500 0 Blue 5
8 PM Mon 76 76 W 6 1449 1500 0 Blue 2
9 PM Mon 73 73 W 5 1282 1500 0 Blue 0
10 PM Mon 71 71 W 5 1146 1500 0 Blue 0
11 PM Mon 69 69 W 3 1010 1500 0 Blue 0
12 Midnight Tue 67 67 W 2 875 1500 0 Blue 0
1 AM Tue 66 66 SW 2 807 1500 0 Blue 0
2 AM Tue 65 65 W 1 807 1500 0 Blue 0
3 AM Tue 64 64 SW 1 807 1500 0 Blue 0
4 AM Tue 63 63 SW 0 807 1500 0 Blue 0
5 AM Tue 63 63 SW 0 807 1500 0 Blue 0
6 AM Tue 63 63 SW 1 807 1500 0 Blue 0
7 AM Tue 64 64 SW 1 807 1500 0 Blue 0
8 AM Tue 66 66 W 2 807 1500 0 Blue 0
9 AM Tue 71 73 W 3 1282 1500 0 Blue 0
10 AM Tue 76 80 W 5 1669 1500 0 Blue 6
11 AM Tue 81 87 W 8 2702 2207 707 Blue 13
12 Noon Tue 84 91 W 10 3524 3087 1587 Blue 17
1 PM Tue 85 92 W 10 4281 3231 1731 Blue 18
2 PM Tue 85 92 W 12 4281 3231 1731 Blue 18
3 PM Tue 86 91 W 12 3524 3087 1587 Blue 17
4 PM Tue 85 89 W 12 3241 2464 964 Blue 15
5 PM Tue 83 85 W 10 2309 2088 588 Blue 11
6 PM Tue 80 80 W 9 1669 1500 0 Blue 6
7 PM Tue 76 76 W 8 1449 1500 0 Blue 2
8 PM Tue 73 73 W 6 1282 1500 0 Blue 0
9 PM Tue 71 71 W 5 1146 1500 0 Blue 0
10 PM Tue 69 69 W 5 1010 1500 0 Blue 0
11 PM Tue 68 68 SW 3 942 1500 0 Blue 0
12 Midnight Wed 66 66 SW 3 807 1500 0 Blue 0
1 AM Wed 65 65 W 2 807 1500 0 Blue 0
2 AM Wed 64 64 SW 2 807 1500 0 Blue 0
3 AM Wed 63 63 SW 1 807 1500 0 Blue 0
4 AM Wed 62 62 SW 1 807 1500 0 Blue 0
5 AM Wed 62 62 W 1 807 1500 0 Blue 0
6 AM Wed 63 63 W 1 807 1500 0 Blue 0
7 AM Wed 65 65 W 1 807 1500 0 Blue 0
8 AM Wed 68 68 W 1 942 1500 0 Blue 0
9 AM Wed 71 73 W 1 1282 1500 0 Blue 0
10 AM Wed 75 79 W 1 1595 1500 0 Blue 5
11 AM Wed 79 85 W 2 2309 2088 588 Blue 11
12 Noon Wed 82 89 W 2 3241 2464 964 Blue 15
1 PM Wed 84 92 W 2 4281 3231 1731 Blue 18
2 PM Wed 85 92 W 6 4281 3231 1731 Blue 18
3 PM Wed 85 91 W 6 3524 3087 1587 Blue 17
4 PM Wed 86 90 W 6 3383 2670 1170 Blue 16
5 PM Wed 84 86 W 5 2473 2144 644 Blue 12
6 PM Wed 81 81 W 5 2029 1545 45 Blue 7
7 PM Wed 77 77 W 5 1497 1500 0 Blue 3
8 PM Wed 74 74 W 2 1350 1500 0 Blue 0
9 PM Wed 71 71 W 2 1146 1500 0 Blue 0
10 PM Wed 69 69 W 2 1010 1500 0 Blue 0
11 PM Wed 68 68 W 2 942 1500 0 Blue 0
12 Midnight Thu 67 67 W 2 875 1500 0 Blue 0
1 AM Thu 66 66 W 2 807 1500 0 Blue 0
2 AM Thu 65 65 W 2 807 1500 0 Blue 0
3 AM Thu 64 64 W 2 807 1500 0 Blue 0
4 AM Thu 63 63 W 2 807 1500 0 Blue 0
5 AM Thu 62 62 W 2 807 1500 0 Blue 0
6 AM Thu 62 62 W 2 807 1500 0 Blue 0
7 AM Thu 63 63 W 2 807 1500 0 Blue 0
8 AM Thu 66 66 W 1 807 1500 0 Blue 0
9 AM Thu 70 72 W 1 1214 1500 0 Blue 0
10 AM Thu 75 79 W 1 1595 1500 0 Blue 5
11 AM Thu 80 86 W 1 2473 2144 644 Blue 12
12 Noon Thu 84 91 W 1 3524 3087 1587 Blue 17
1 PM Thu 87 95 W 1 4932 4263 2763 Blue 21
2 PM Thu 89 96 W 5 5208 4440 2940 Blue 22
3 PM Thu 88 94 W 5 4699 3513 2013 Blue 20
4 PM Thu 88 92 W 5 4281 3231 1731 Blue 18
5 PM Thu 86 88 W 5 3097 2305 805 Blue 14
6 PM Thu 83 83 W 5 2146 1667 167 Blue 9
7 PM Thu 79 79 W 5 1595 1500 0 Blue 5
8 PM Thu 76 76 W 2 1449 1500 0 Blue 2
9 PM Thu 74 74 W 2 1350 1500 0 Blue 0
10 PM Thu 72 72 W 2 1214 1500 0 Blue 0
11 PM Thu 71 71 W 2 1146 1500 0 Blue 0
12 Midnight Fri 69 69 W 2 1010 1500 0 Blue 0
1 AM Fri 67 67 W 2 875 1500 0 Blue 0
2 AM Fri 65 65 W 2 807 1500 0 Blue 0
3 AM Fri 64 64 W 2 807 1500 0 Blue 0
4 AM Fri 63 63 W 2 807 1500 0 Blue 0
5 AM Fri 63 63 NW 2 807 1500 0 Blue 0
6 AM Fri 64 64 NW 2 807 1500 0 Blue 0
7 AM Fri 66 66 NW 2 807 1500 0 Blue 0
8 AM Fri 69 69 W 1 1010 1500 0 Blue 0
9 AM Fri 73 75 W 1 1400 1500 0 Blue 1
10 AM Fri 78 82 W 1 2090 1594 94 Blue 8
11 AM Fri 82 88 W 2 3097 2305 805 Blue 14
12 Noon Fri 86 93 W 2 4465 3373 1873 Blue 19
1 PM Fri 88 96 W 2 5208 4440 2940 Blue 22
2 PM Fri 88 95 W 6 4932 4263 2763 Blue 21
3 PM Fri 89 95 W 6 4932 4263 2763 Blue 21
4 PM Fri 87 91 W 6 3524 3087 1587 Blue 17
5 PM Fri 85 87 W 5 2702 2207 707 Blue 13
6 PM Fri 81 81 W 5 2029 1545 45 Blue 7
7 PM Fri 78 78 W 5 1546 1500 0 Blue 4
8 PM Fri 74 74 W 2 1350 1500 0 Blue 0
9 PM Fri 72 72 W 2 1214 1500 0 Blue 0
10 PM Fri 70 70 W 2 1078 1500 0 Blue 0
11 PM Fri 68 68 W 2 942 1500 0 Blue 0
12 Midnight Sat 66 66 W 2 807 1500 0 Blue 0
1 AM Sat 64 64 W 2 807 1500 0 Blue 0
2 AM Sat 62 62 W 2 807 1500 0 Blue 0
3 AM Sat 62 62 W 2 807 1500 0 Blue 0
4 AM Sat 62 62 W 2 807 1500 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