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

Station:

KNKX

Date/Time:

21 JAN 2018

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)
4 AM Sun 44 44 E 8 968 1500 0 Blue 0
5 AM Sun 42 42 E 8 968 1500 0 Blue 0
6 AM Sun 42 42 E 7 968 1500 0 Blue 0
7 AM Sun 43 43 E 7 968 1500 0 Blue 0
8 AM Sun 47 47 SE 7 968 1500 0 Blue 0
9 AM Sun 53 54 S 6 1799 1500 0 Blue 1
10 AM Sun 57 58 S 6 4707 3357 1857 White 5
11 AM Sun 60 62 SW 6 5559 5245 3745 White 9
12 Noon Sun 61 63 SW 5 5769 5542 4042 White 10
1 PM Sun 61 63 W 6 5769 5542 4042 White 10
2 PM Sun 62 63 W 6 5769 5542 4042 White 10
3 PM Sun 61 61 W 6 5349 4839 3339 White 8
4 PM Sun 60 60 W 7 5138 4107 2607 White 7
5 PM Sun 56 56 W 7 3835 1500 0 Blue 3
6 PM Sun 52 52 W 5 1059 1500 0 Blue 0
7 PM Sun 48 48 NE 5 968 1500 0 Blue 0
8 PM Sun 46 46 NE 6 968 1500 0 Blue 0
9 PM Sun 46 46 NE 6 968 1500 0 Blue 0
10 PM Sun 46 46 NE 7 968 1500 0 Blue 0
11 PM Sun 46 46 NE 7 968 1500 0 Blue 0
12 Midnight Mon 45 45 NE 6 968 1500 0 Blue 0
1 AM Mon 45 45 E 5 968 1500 0 Blue 0
2 AM Mon 45 45 E 5 968 1500 0 Blue 0
3 AM Mon 46 46 E 5 968 1500 0 Blue 0
4 AM Mon 46 46 E 3 968 1500 0 Blue 0
5 AM Mon 46 46 E 3 968 1500 0 Blue 0
6 AM Mon 45 45 E 3 968 1500 0 Blue 0
7 AM Mon 46 46 E 3 968 1500 0 Blue 0
8 AM Mon 50 50 E 3 968 1500 0 Blue 0
9 AM Mon 54 54 SE 1 1799 1500 0 Blue 1
10 AM Mon 59 60 SW 3 5138 4107 2607 White 7
11 AM Mon 62 64 W 3 5979 5667 4167 White 11
12 Noon Mon 64 66 W 3 6397 5916 4416 White 13
1 PM Mon 66 68 W 5 6813 6813 5313 White 15
2 PM Mon 66 67 W 6 6605 6605 5105 White 14
3 PM Mon 66 66 W 7 6397 5916 4416 White 13
4 PM Mon 66 66 W 6 6397 5916 4416 White 13
5 PM Mon 62 62 NW 2 5559 5245 3745 White 9
6 PM Mon 58 58 N 2 4707 3357 1857 White 5
7 PM Mon 55 55 N 6 3502 1500 0 Blue 2
8 PM Mon 53 53 N 5 1447 1500 0 Blue 0
9 PM Mon 52 52 NE 2 1059 1500 0 Blue 0
10 PM Mon 52 52 E 1 1059 1500 0 Blue 0
11 PM Mon 51 51 E 1 968 1500 0 Blue 0
12 Midnight Tue 51 51 E 1 968 1500 0 Blue 0
1 AM Tue 50 50 E 2 968 1500 0 Blue 0
2 AM Tue 50 50 NE 2 968 1500 0 Blue 0
3 AM Tue 50 50 NE 2 968 1500 0 Blue 0
4 AM Tue 50 50 NE 3 968 1500 0 Blue 0
5 AM Tue 49 49 E 2 968 1500 0 Blue 0
6 AM Tue 49 49 E 1 968 1500 0 Blue 0
7 AM Tue 51 51 N 1 968 1500 0 Blue 0
8 AM Tue 56 56 NW 1 3835 1500 0 Blue 3
9 AM Tue 63 64 NW 1 5979 5667 4167 White 11
10 AM Tue 68 70 W 6 7229 7229 5729 White 17
11 AM Tue 72 75 W 6 8254 8254 6754 White 22
12 Noon Tue 73 76 W 6 8459 8459 6959 White 23
1 PM Tue 73 75 W 6 8254 8254 6754 White 22
2 PM Tue 74 76 W 6 8459 8459 6959 White 23
3 PM Tue 73 74 W 5 8048 8048 6548 White 21
4 PM Tue 72 72 S 2 7639 7639 6139 White 19
5 PM Tue 68 68 S 3 6813 6813 5313 White 15
6 PM Tue 63 63 SW 3 5769 5542 4042 White 10
7 PM Tue 58 58 S 3 4707 3357 1857 White 5
8 PM Tue 55 55 S 3 3502 1500 0 Blue 2
9 PM Tue 54 54 S 3 1799 1500 0 Blue 1
10 PM Tue 54 54 SE 2 1799 1500 0 Blue 1
11 PM Tue 55 55 E 6 3502 1500 0 Blue 2
12 Midnight Wed 56 56 E 9 3835 1500 0 Blue 3
1 AM Wed 57 57 E 12 4139 1790 290 Blue 4
2 AM Wed 57 57 E 12 4139 1790 290 Blue 4
3 AM Wed 56 56 E 12 3835 1500 0 Blue 3
4 AM Wed 54 54 E 8 1799 1500 0 Blue 1
5 AM Wed 53 53 E 8 1447 1500 0 Blue 0
6 AM Wed 53 53 E 8 1447 1500 0 Blue 0
7 AM Wed 55 55 N 6 3502 1500 0 Blue 2
8 AM Wed 60 60 N 6 5138 4107 2607 White 7
9 AM Wed 66 67 N 6 6605 6605 5105 White 14
10 AM Wed 71 73 W 5 7844 7844 6344 White 20
11 AM Wed 74 76 W 5 8459 8459 6959 White 23
12 Noon Wed 75 77 W 5 8664 8664 7164 White 23
1 PM Wed 75 77 W 6 8664 8664 7164 White 23
2 PM Wed 74 75 W 6 8254 8254 6754 White 22
3 PM Wed 73 74 W 6 8048 8048 6548 White 21
4 PM Wed 71 71 SW 7 7434 7434 5934 White 18
5 PM Wed 68 68 SW 7 6813 6813 5313 White 15
6 PM Wed 65 65 SW 7 6188 5791 4291 White 12
7 PM Wed 62 62 SW 5 5559 5245 3745 White 9
8 PM Wed 60 60 SW 5 5138 4107 2607 White 7
9 PM Wed 58 58 SW 5 4707 3357 1857 White 5
10 PM Wed 57 57 S 2 4139 1790 290 Blue 4
11 PM Wed 56 56 S 2 3835 1500 0 Blue 3
12 Midnight Thu 55 55 S 2 3502 1500 0 Blue 2
1 AM Thu 54 54 S 2 1799 1500 0 Blue 1
2 AM Thu 52 52 S 2 1059 1500 0 Blue 0
3 AM Thu 52 52 S 2 1059 1500 0 Blue 0
4 AM Thu 51 51 SE 5 968 1500 0 Blue 0
5 AM Thu 51 51 SE 5 968 1500 0 Blue 0
6 AM Thu 52 52 SE 5 1059 1500 0 Blue 0
7 AM Thu 55 55 S 6 3502 1500 0 Blue 2
8 AM Thu 58 58 S 6 4707 3357 1857 White 5
9 AM Thu 61 61 S 6 5349 4839 3339 White 8
10 AM Thu 63 64 W 9 5979 5667 4167 White 11
11 AM Thu 63 64 W 9 5979 5667 4167 White 11
12 Noon Thu 62 63 W 9 5769 5542 4042 White 10
1 PM Thu 61 62 W 13 5559 5245 3745 White 9
2 PM Thu 61 62 W 13 5559 5245 3745 White 9
3 PM Thu 61 61 W 13 5349 4839 3339 White 8
4 PM Thu 61 61 W 14 5349 4839 3339 White 8
5 PM Thu 59 59 W 14 4921 3806 2306 White 6
6 PM Thu 57 57 W 14 4139 1790 290 Blue 4
7 PM Thu 54 54 N 9 1799 1500 0 Blue 1
8 PM Thu 52 52 N 9 1059 1500 0 Blue 0
9 PM Thu 51 51 N 9 968 1500 0 Blue 0
10 PM Thu 50 50 NE 3 968 1500 0 Blue 0
11 PM Thu 49 49 NE 3 968 1500 0 Blue 0
12 Midnight Fri 48 48 NE 3 968 1500 0 Blue 0
1 AM Fri 48 48 NE 5 968 1500 0 Blue 0
2 AM Fri 48 48 NE 5 968 1500 0 Blue 0
3 AM Fri 48 48 NE 5 968 1500 0 Blue 0
4 AM Fri 47 47 NE 6 968 1500 0 Blue 0
5 AM Fri 46 46 NE 6 968 1500 0 Blue 0
6 AM Fri 46 46 NE 6 968 1500 0 Blue 0
7 AM Fri 47 47 N 6 968 1500 0 Blue 0
8 AM Fri 50 50 N 6 968 1500 0 Blue 0
9 AM Fri 53 54 N 6 1799 1500 0 Blue 1
10 AM Fri 56 58 W 5 4707 3357 1857 White 5
11 AM Fri 59 61 W 5 5349 4839 3339 White 8
12 Noon Fri 60 62 W 5 5559 5245 3745 White 9
1 PM Fri 61 63 W 7 5769 5542 4042 White 10
2 PM Fri 63 64 W 7 5979 5667 4167 White 11
3 PM Fri 64 65 W 7 6188 5791 4291 White 12
4 PM Fri 64 64 NW 8 5979 5667 4167 White 11
5 PM Fri 61 61 NW 8 5349 4839 3339 White 8
6 PM Fri 57 57 NW 8 4139 1790 290 Blue 4
7 PM Fri 53 53 NW 7 1447 1500 0 Blue 0
8 PM Fri 51 51 NW 7 968 1500 0 Blue 0
9 PM Fri 50 50 NW 7 968 1500 0 Blue 0
10 PM Fri 50 50 NW 6 968 1500 0 Blue 0
11 PM Fri 51 51 NW 6 968 1500 0 Blue 0
12 Midnight Sat 53 53 NW 6 1447 1500 0 Blue 0
1 AM Sat 54 54 N 9 1799 1500 0 Blue 1
2 AM Sat 55 55 N 9 3502 1500 0 Blue 2
3 AM Sat 55 55 N 9 3502 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