Detailed Predictions for: Rainbow Valley
Launch Altitude (f): 1125
LZ Altitude (f): 80
Sounding

Station:

KTUS

Date/Time:

19 NOV 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 Tue 59 59 SE 2 0 1125 0 Blue 0
6 AM Tue 58 58 SE 2 0 1125 0 Blue 0
7 AM Tue 57 57 E 2 0 1125 0 Blue 0
8 AM Tue 60 60 E 2 0 1125 0 Blue 0
9 AM Tue 65 65 E 2 0 1125 0 Blue 0
10 AM Tue 72 72 E 2 2688 2622 1497 Blue 6
11 AM Tue 75 76 E 2 2781 2709 1584 Blue 10
12 Noon Tue 77 78 E 2 3117 2752 1627 Blue 12
1 PM Tue 77 78 E 3 3117 2752 1627 Blue 12
2 PM Tue 76 76 E 3 2781 2709 1584 Blue 10
3 PM Tue 76 76 E 6 2781 2709 1584 Blue 10
4 PM Tue 75 75 E 8 2753 2687 1562 Blue 9
5 PM Tue 73 73 E 10 2710 2644 1519 Blue 7
6 PM Tue 71 71 E 9 2666 2600 1475 Blue 5
7 PM Tue 69 69 SE 8 2623 2470 1345 Blue 3
8 PM Tue 68 68 SE 8 2601 2470 1345 Blue 2
9 PM Tue 67 67 SE 8 2566 2470 1345 Blue 1
10 PM Tue 66 66 SE 8 0 1125 0 Blue 0
11 PM Tue 65 65 SE 8 0 1125 0 Blue 0
12 Midnight Wed 65 65 SE 9 0 1125 0 Blue 0
1 AM Wed 65 65 S 9 0 1125 0 Blue 0
2 AM Wed 64 64 S 10 0 1125 0 Blue 0
3 AM Wed 64 64 S 12 0 1125 0 Blue 0
4 AM Wed 63 63 S 14 0 1125 0 Blue 0
5 AM Wed 63 63 S 15 0 1125 0 Blue 0
6 AM Wed 62 62 S 16 0 1125 0 Blue 0
7 AM Wed 60 60 S 17 0 1125 0 Blue 0
8 AM Wed 61 61 S 18 0 1125 0 Blue 0
9 AM Wed 64 64 S 20 0 1125 0 Blue 0
10 AM Wed 65 65 S 20 0 1125 0 Blue 0
11 AM Wed 66 66 S 20 0 1125 0 Blue 0
12 Noon Wed 66 66 S 20 0 1125 0 Blue 0
1 PM Wed 66 66 S 18 0 1125 0 Blue 0
2 PM Wed 65 65 S 18 0 1125 0 Blue 0
3 PM Wed 65 65 S 17 0 1125 0 Blue 0
4 PM Wed 63 63 SW 16 0 1125 0 Blue 0
5 PM Wed 62 62 SW 16 0 1125 0 Blue 0
6 PM Wed 60 60 SW 14 0 1125 0 Blue 0
7 PM Wed 59 59 S 13 0 1125 0 Blue 0
8 PM Wed 58 58 S 10 0 1125 0 Blue 0
9 PM Wed 57 57 S 10 0 1125 0 Blue 0
10 PM Wed 56 56 S 9 0 1125 0 Blue 0
11 PM Wed 56 56 S 9 0 1125 0 Blue 0
12 Midnight Thu 56 56 S 9 0 1125 0 Blue 0
1 AM Thu 55 55 S 9 0 1125 0 Blue 0
2 AM Thu 55 55 S 9 0 1125 0 Blue 0
3 AM Thu 55 55 S 9 0 1125 0 Blue 0
4 AM Thu 54 54 S 8 0 1125 0 Blue 0
5 AM Thu 53 53 S 7 0 1125 0 Blue 0
6 AM Thu 53 53 S 6 0 1125 0 Blue 0
7 AM Thu 54 54 S 5 0 1125 0 Blue 0
8 AM Thu 55 55 S 5 0 1125 0 Blue 0
9 AM Thu 58 58 S 5 0 1125 0 Blue 0
10 AM Thu 61 61 SW 6 0 1125 0 Blue 0
11 AM Thu 64 65 SW 7 0 1125 0 Blue 0
12 Noon Thu 65 66 SW 7 0 1125 0 Blue 0
1 PM Thu 65 66 SW 6 0 1125 0 Blue 0
2 PM Thu 65 66 SW 6 0 1125 0 Blue 0
3 PM Thu 65 65 SW 5 0 1125 0 Blue 0
4 PM Thu 66 66 SW 5 0 1125 0 Blue 0
5 PM Thu 65 65 SW 3 0 1125 0 Blue 0
6 PM Thu 63 63 SW 3 0 1125 0 Blue 0
7 PM Thu 61 61 S 3 0 1125 0 Blue 0
8 PM Thu 58 58 S 3 0 1125 0 Blue 0
9 PM Thu 57 57 S 3 0 1125 0 Blue 0
10 PM Thu 56 56 SE 3 0 1125 0 Blue 0
11 PM Thu 55 55 SE 3 0 1125 0 Blue 0
12 Midnight Fri 55 55 SE 3 0 1125 0 Blue 0
1 AM Fri 54 54 SE 2 0 1125 0 Blue 0
2 AM Fri 53 53 SE 2 0 1125 0 Blue 0
3 AM Fri 53 53 SE 2 0 1125 0 Blue 0
4 AM Fri 53 53 SE 2 0 1125 0 Blue 0
5 AM Fri 52 52 SE 2 0 1125 0 Blue 0
6 AM Fri 52 52 E 3 0 1125 0 Blue 0
7 AM Fri 51 51 E 3 0 1125 0 Blue 0
8 AM Fri 52 52 E 3 0 1125 0 Blue 0
9 AM Fri 55 55 E 5 0 1125 0 Blue 0
10 AM Fri 60 61 E 5 0 1125 0 Blue 0
11 AM Fri 63 65 E 5 0 1125 0 Blue 0
12 Noon Fri 65 68 E 6 2601 2470 1345 Blue 2
1 PM Fri 66 68 E 6 2601 2470 1345 Blue 2
2 PM Fri 66 68 E 6 2601 2470 1345 Blue 2
3 PM Fri 66 67 E 6 2566 2470 1345 Blue 1
4 PM Fri 66 66 E 6 0 1125 0 Blue 0
5 PM Fri 65 65 E 6 0 1125 0 Blue 0
6 PM Fri 63 63 E 6 0 1125 0 Blue 0
7 PM Fri 60 60 NE 5 0 1125 0 Blue 0
8 PM Fri 57 57 NE 5 0 1125 0 Blue 0
9 PM Fri 55 55 NE 5 0 1125 0 Blue 0
10 PM Fri 54 54 NE 3 0 1125 0 Blue 0
11 PM Fri 53 53 N 3 0 1125 0 Blue 0
12 Midnight Sat 52 52 NE 3 0 1125 0 Blue 0
1 AM Sat 52 52 NE 3 0 1125 0 Blue 0
2 AM Sat 51 51 NE 3 0 1125 0 Blue 0
3 AM Sat 51 51 NE 3 0 1125 0 Blue 0
4 AM Sat 50 50 NE 3 0 1125 0 Blue 0
5 AM Sat 49 49 NE 3 0 1125 0 Blue 0
6 AM Sat 48 48 NE 3 0 1125 0 Blue 0
7 AM Sat 48 48 NE 5 0 1125 0 Blue 0
8 AM Sat 49 49 NE 5 0 1125 0 Blue 0
9 AM Sat 54 54 NE 6 0 1125 0 Blue 0
10 AM Sat 60 61 E 6 0 1125 0 Blue 0
11 AM Sat 65 66 E 6 0 1125 0 Blue 0
12 Noon Sat 68 70 E 6 2645 2564 1439 Blue 4
1 PM Sat 69 71 NE 6 2666 2600 1475 Blue 5
2 PM Sat 69 70 NE 5 2645 2564 1439 Blue 4
3 PM Sat 69 70 NE 5 2645 2564 1439 Blue 4
4 PM Sat 69 69 NE 5 2623 2470 1345 Blue 3
5 PM Sat 68 68 NE 3 2601 2470 1345 Blue 2
6 PM Sat 65 65 NE 3 0 1125 0 Blue 0
7 PM Sat 62 62 NE 3 0 1125 0 Blue 0
8 PM Sat 59 59 N 3 0 1125 0 Blue 0
9 PM Sat 57 57 N 3 0 1125 0 Blue 0
10 PM Sat 56 56 N 3 0 1125 0 Blue 0
11 PM Sat 55 55 N 3 0 1125 0 Blue 0
12 Midnight Sun 54 54 N 3 0 1125 0 Blue 0
1 AM Sun 53 53 N 3 0 1125 0 Blue 0
2 AM Sun 52 52 N 3 0 1125 0 Blue 0
3 AM Sun 51 51 NE 3 0 1125 0 Blue 0
4 AM Sun 50 50 NE 3 0 1125 0 Blue 0
5 AM Sun 50 50 NE 3 0 1125 0 Blue 0
6 AM Sun 49 49 NE 3 0 1125 0 Blue 0
7 AM Sun 49 49 NE 3 0 1125 0 Blue 0
8 AM Sun 51 51 NE 3 0 1125 0 Blue 0
9 AM Sun 55 55 NE 3 0 1125 0 Blue 0
10 AM Sun 60 60 NE 3 0 1125 0 Blue 0
11 AM Sun 65 66 NE 3 0 1125 0 Blue 0
12 Noon Sun 68 69 NE 3 2623 2470 1345 Blue 3
1 PM Sun 70 71 NE 3 2666 2600 1475 Blue 5
2 PM Sun 70 71 N 3 2666 2600 1475 Blue 5
3 PM Sun 71 72 N 2 2688 2622 1497 Blue 6
4 PM Sun 71 71 N 2 2666 2600 1475 Blue 5
5 PM Sun 69 69 NW 2 2623 2470 1345 Blue 3
6 PM Sun 66 66 NW 2 0 1125 0 Blue 0
7 PM Sun 62 62 NW 2 0 1125 0 Blue 0
8 PM Sun 59 59 NW 2 0 1125 0 Blue 0
9 PM Sun 57 57 NW 2 0 1125 0 Blue 0
10 PM Sun 56 56 NW 2 0 1125 0 Blue 0
11 PM Sun 55 55 NW 2 0 1125 0 Blue 0
12 Midnight Mon 54 54 N 2 0 1125 0 Blue 0
1 AM Mon 53 53 N 2 0 1125 0 Blue 0
2 AM Mon 52 52 N 2 0 1125 0 Blue 0
3 AM Mon 51 51 NE 2 0 1125 0 Blue 0
4 AM Mon 50 50 NE 2 0 1125 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

Supported By: Alan Crouse ac_soaring@yahoo.com