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

Station:

KNKX

Date/Time:

18 MAY 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 Sat 50 50 NE 2 771 1500 0 Blue 0
6 AM Sat 50 50 NE 2 771 1500 0 Blue 0
7 AM Sat 50 50 E 1 771 1500 0 Blue 0
8 AM Sat 52 53 W 1 771 1500 0 Blue 0
9 AM Sat 55 58 W 2 2023 1500 0 Blue 3
10 AM Sat 57 62 W 3 2884 2320 820 Blue 7
11 AM Sat 60 65 W 7 3958 2871 1371 Blue 10
12 Noon Sat 64 70 W 8 4731 4120 2620 Blue 15
1 PM Sat 66 72 W 9 5132 4315 2815 Blue 17
2 PM Sat 68 73 W 10 5240 4686 3186 Blue 18
3 PM Sat 68 72 W 12 5132 4315 2815 Blue 17
4 PM Sat 69 72 W 12 5132 4315 2815 Blue 17
5 PM Sat 67 68 W 10 4174 3931 2431 Blue 13
6 PM Sat 65 65 W 9 3958 2871 1371 Blue 10
7 PM Sat 62 62 W 8 2884 2320 820 Blue 7
8 PM Sat 59 59 W 6 2327 1500 0 Blue 4
9 PM Sat 57 57 W 6 1751 1500 0 Blue 2
10 PM Sat 56 56 W 5 1479 1500 0 Blue 1
11 PM Sat 55 55 SW 5 1178 1500 0 Blue 0
12 Midnight Sun 55 55 SW 5 1178 1500 0 Blue 0
1 AM Sun 54 54 W 5 800 1500 0 Blue 0
2 AM Sun 55 55 W 5 1178 1500 0 Blue 0
3 AM Sun 54 54 W 5 800 1500 0 Blue 0
4 AM Sun 54 54 SW 5 800 1500 0 Blue 0
5 AM Sun 53 53 W 5 771 1500 0 Blue 0
6 AM Sun 53 53 SW 5 771 1500 0 Blue 0
7 AM Sun 53 53 SW 6 771 1500 0 Blue 0
8 AM Sun 54 54 S 6 800 1500 0 Blue 0
9 AM Sun 55 55 SW 7 1178 1500 0 Blue 0
10 AM Sun 56 56 SW 8 1479 1500 0 Blue 1
11 AM Sun 57 59 SW 10 2327 1500 0 Blue 4
12 Noon Sun 59 61 SW 10 2676 2013 513 Blue 6
1 PM Sun 60 62 SW 12 2884 2320 820 Blue 7
2 PM Sun 61 63 W 12 3168 2477 977 Blue 8
3 PM Sun 60 61 W 13 2676 2013 513 Blue 6
4 PM Sun 61 62 W 14 2884 2320 820 Blue 7
5 PM Sun 60 61 W 14 2676 2013 513 Blue 6
6 PM Sun 59 59 W 14 2327 1500 0 Blue 4
7 PM Sun 57 57 W 13 1751 1500 0 Blue 2
8 PM Sun 56 56 W 13 1479 1500 0 Blue 1
9 PM Sun 54 54 W 13 800 1500 0 Blue 0
10 PM Sun 54 54 W 13 800 1500 0 Blue 0
11 PM Sun 53 53 W 13 771 1500 0 Blue 0
12 Midnight Mon 53 53 W 12 771 1500 0 Blue 0
1 AM Mon 53 53 W 12 771 1500 0 Blue 0
2 AM Mon 53 53 W 10 771 1500 0 Blue 0
3 AM Mon 53 53 W 10 771 1500 0 Blue 0
4 AM Mon 53 53 W 10 771 1500 0 Blue 0
5 AM Mon 52 52 W 10 771 1500 0 Blue 0
6 AM Mon 52 52 W 12 771 1500 0 Blue 0
7 AM Mon 52 52 W 13 771 1500 0 Blue 0
8 AM Mon 53 53 W 13 771 1500 0 Blue 0
9 AM Mon 54 54 W 13 800 1500 0 Blue 0
10 AM Mon 56 56 W 13 1479 1500 0 Blue 1
11 AM Mon 57 61 W 13 2676 2013 513 Blue 6
12 Noon Mon 58 63 W 13 3168 2477 977 Blue 8
1 PM Mon 60 65 W 13 3958 2871 1371 Blue 10
2 PM Mon 61 66 W 14 4075 3139 1639 Blue 11
3 PM Mon 60 64 W 14 3572 2664 1164 Blue 9
4 PM Mon 61 63 W 13 3168 2477 977 Blue 8
5 PM Mon 60 61 W 13 2676 2013 513 Blue 6
6 PM Mon 59 59 W 12 2327 1500 0 Blue 4
7 PM Mon 57 57 W 10 1751 1500 0 Blue 2
8 PM Mon 56 56 W 9 1479 1500 0 Blue 1
9 PM Mon 54 54 W 7 800 1500 0 Blue 0
10 PM Mon 54 54 W 5 800 1500 0 Blue 0
11 PM Mon 53 53 W 3 771 1500 0 Blue 0
12 Midnight Tue 53 53 W 5 771 1500 0 Blue 0
1 AM Tue 53 53 W 6 771 1500 0 Blue 0
2 AM Tue 53 53 W 7 771 1500 0 Blue 0
3 AM Tue 53 53 SW 8 771 1500 0 Blue 0
4 AM Tue 53 53 SW 9 771 1500 0 Blue 0
5 AM Tue 52 52 SW 9 771 1500 0 Blue 0
6 AM Tue 52 52 SW 9 771 1500 0 Blue 0
7 AM Tue 52 52 SW 9 771 1500 0 Blue 0
8 AM Tue 53 53 SW 13 771 1500 0 Blue 0
9 AM Tue 54 54 SW 13 800 1500 0 Blue 0
10 AM Tue 54 55 SW 13 1178 1500 0 Blue 0
11 AM Tue 55 56 W 14 1479 1500 0 Blue 1
12 Noon Tue 56 57 W 14 1751 1500 0 Blue 2
1 PM Tue 57 58 W 14 2023 1500 0 Blue 3
2 PM Tue 58 59 W 18 2327 1500 0 Blue 4
3 PM Tue 58 59 W 18 2327 1500 0 Blue 4
4 PM Tue 58 58 W 18 2023 1500 0 Blue 3
5 PM Tue 57 57 W 20 1751 1500 0 Blue 2
6 PM Tue 56 56 W 20 1479 1500 0 Blue 1
7 PM Tue 55 55 W 20 1178 1500 0 Blue 0
8 PM Tue 54 54 W 15 800 1500 0 Blue 0
9 PM Tue 53 53 W 15 771 1500 0 Blue 0
10 PM Tue 52 52 W 15 771 1500 0 Blue 0
11 PM Tue 52 52 W 9 771 1500 0 Blue 0
12 Midnight Wed 52 52 W 9 771 1500 0 Blue 0
1 AM Wed 52 52 W 9 771 1500 0 Blue 0
2 AM Wed 52 52 SW 5 771 1500 0 Blue 0
3 AM Wed 52 52 SW 5 771 1500 0 Blue 0
4 AM Wed 52 52 SW 5 771 1500 0 Blue 0
5 AM Wed 51 51 S 5 771 1500 0 Blue 0
6 AM Wed 51 51 S 5 771 1500 0 Blue 0
7 AM Wed 51 51 S 5 771 1500 0 Blue 0
8 AM Wed 52 52 S 6 771 1500 0 Blue 0
9 AM Wed 54 54 S 6 800 1500 0 Blue 0
10 AM Wed 55 55 S 6 1178 1500 0 Blue 0
11 AM Wed 57 61 SW 6 2676 2013 513 Blue 6
12 Noon Wed 59 63 SW 6 3168 2477 977 Blue 8
1 PM Wed 60 64 SW 6 3572 2664 1164 Blue 9
2 PM Wed 62 66 W 10 4075 3139 1639 Blue 11
3 PM Wed 62 65 W 10 3958 2871 1371 Blue 10
4 PM Wed 62 64 W 10 3572 2664 1164 Blue 9
5 PM Wed 61 62 W 10 2884 2320 820 Blue 7
6 PM Wed 60 60 W 10 2484 1744 244 Blue 5
7 PM Wed 58 58 W 10 2023 1500 0 Blue 3
8 PM Wed 55 55 W 6 1178 1500 0 Blue 0
9 PM Wed 54 54 W 6 800 1500 0 Blue 0
10 PM Wed 53 53 W 6 771 1500 0 Blue 0
11 PM Wed 53 53 SW 2 771 1500 0 Blue 0
12 Midnight Thu 52 52 SW 2 771 1500 0 Blue 0
1 AM Thu 52 52 SW 2 771 1500 0 Blue 0
2 AM Thu 52 52 S 2 771 1500 0 Blue 0
3 AM Thu 52 52 S 2 771 1500 0 Blue 0
4 AM Thu 52 52 S 2 771 1500 0 Blue 0
5 AM Thu 51 51 NE 1 771 1500 0 Blue 0
6 AM Thu 51 51 NE 1 771 1500 0 Blue 0
7 AM Thu 51 51 NE 1 771 1500 0 Blue 0
8 AM Thu 53 54 W 3 800 1500 0 Blue 0
9 AM Thu 55 57 W 3 1751 1500 0 Blue 2
10 AM Thu 57 61 W 3 2676 2013 513 Blue 6
11 AM Thu 60 65 W 6 3958 2871 1371 Blue 10
12 Noon Thu 63 69 W 6 4356 4063 2563 Blue 14
1 PM Thu 65 71 W 6 5024 4169 2669 Blue 16
2 PM Thu 66 71 W 10 5024 4169 2669 Blue 16
3 PM Thu 67 71 W 10 5024 4169 2669 Blue 16
4 PM Thu 67 70 W 10 4731 4120 2620 Blue 15
5 PM Thu 65 66 SW 12 4075 3139 1639 Blue 11
6 PM Thu 64 64 SW 12 3572 2664 1164 Blue 9
7 PM Thu 61 61 SW 12 2676 2013 513 Blue 6
8 PM Thu 58 58 W 7 2023 1500 0 Blue 3
9 PM Thu 56 56 W 7 1479 1500 0 Blue 1
10 PM Thu 55 55 W 7 1178 1500 0 Blue 0
11 PM Thu 54 54 S 2 800 1500 0 Blue 0
12 Midnight Fri 54 54 S 2 800 1500 0 Blue 0
1 AM Fri 53 53 S 2 771 1500 0 Blue 0
2 AM Fri 54 54 SW 3 800 1500 0 Blue 0
3 AM Fri 53 53 SW 3 771 1500 0 Blue 0
4 AM Fri 53 53 SW 3 771 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