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

Station:

KTUS

Date/Time:

12Z 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)
6 AM Sat 59 59 S 5 0 1125 0 Blue 0
7 AM Sat 58 58 S 5 0 1125 0 Blue 0
8 AM Sat 59 60 S 3 0 1125 0 Blue 0
9 AM Sat 65 67 SW 3 0 1125 0 Blue 0
10 AM Sat 68 72 SW 3 0 1125 0 Blue 0
11 AM Sat 74 79 SW 3 4303 2612 1487 Blue 2
12 Noon Sat 77 83 W 5 7134 4774 3649 Blue 6
1 PM Sat 80 86 W 6 9076 7054 5929 Blue 9
2 PM Sat 83 88 W 7 9826 8029 6904 Blue 10
3 PM Sat 84 88 W 8 9826 8029 6904 Blue 10
4 PM Sat 85 87 W 10 9454 7467 6342 Blue 9
5 PM Sat 85 85 W 10 8248 6667 5542 Blue 8
6 PM Sat 86 86 W 12 9076 7054 5929 Blue 9
7 PM Sat 84 84 W 12 7552 5701 4576 Blue 7
8 PM Sat 81 81 W 10 5839 3714 2589 Blue 4
9 PM Sat 77 77 W 9 0 1125 0 Blue 0
10 PM Sat 75 75 W 8 0 1125 0 Blue 0
11 PM Sat 72 72 W 7 0 1125 0 Blue 0
12 Midnight Sun 69 69 W 6 0 1125 0 Blue 0
1 AM Sun 66 66 W 5 0 1125 0 Blue 0
2 AM Sun 65 65 W 5 0 1125 0 Blue 0
3 AM Sun 64 64 W 3 0 1125 0 Blue 0
4 AM Sun 62 62 W 3 0 1125 0 Blue 0
5 AM Sun 61 61 W 3 0 1125 0 Blue 0
6 AM Sun 60 60 NW 3 0 1125 0 Blue 0
7 AM Sun 59 59 NW 3 0 1125 0 Blue 0
8 AM Sun 60 61 NW 3 0 1125 0 Blue 0
9 AM Sun 66 68 NW 3 0 1125 0 Blue 0
10 AM Sun 70 74 NW 3 0 1125 0 Blue 0
11 AM Sun 75 80 NW 3 4836 2612 1487 Blue 3
12 Noon Sun 79 85 NW 5 8248 6667 5542 Blue 8
1 PM Sun 82 88 NW 6 9826 8029 6904 Blue 10
2 PM Sun 85 90 NW 7 10353 9354 8229 Blue 12
3 PM Sun 86 90 NW 8 10353 9354 8229 Blue 12
4 PM Sun 87 89 NW 9 10154 8947 7822 Blue 11
5 PM Sun 87 87 W 9 9454 7467 6342 Blue 9
6 PM Sun 88 88 W 10 9826 8029 6904 Blue 10
7 PM Sun 85 85 W 10 8248 6667 5542 Blue 8
8 PM Sun 82 82 W 10 6736 4251 3126 Blue 5
9 PM Sun 78 78 W 9 3757 2612 1487 Blue 1
10 PM Sun 76 76 W 8 0 1125 0 Blue 0
11 PM Sun 73 73 W 8 0 1125 0 Blue 0
12 Midnight Mon 69 69 W 7 0 1125 0 Blue 0
1 AM Mon 66 66 W 6 0 1125 0 Blue 0
2 AM Mon 64 64 NW 5 0 1125 0 Blue 0
3 AM Mon 64 64 N 3 0 1125 0 Blue 0
4 AM Mon 62 62 N 2 0 1125 0 Blue 0
5 AM Mon 60 60 NE 2 0 1125 0 Blue 0
6 AM Mon 59 59 NE 1 0 1125 0 Blue 0
7 AM Mon 58 58 NE 1 0 1125 0 Blue 0
8 AM Mon 60 60 NE 1 0 1125 0 Blue 0
9 AM Mon 66 68 NE 1 0 1125 0 Blue 0
10 AM Mon 70 74 NE 1 0 1125 0 Blue 0
11 AM Mon 76 81 NE 2 5839 3714 2589 Blue 4
12 Noon Mon 80 86 NE 2 9076 7054 5929 Blue 9
1 PM Mon 83 89 NE 3 10154 8947 7822 Blue 11
2 PM Mon 87 92 N 3 10902 10096 8971 Blue 14
3 PM Mon 88 91 N 3 10615 9722 8597 Blue 13
4 PM Mon 89 91 N 5 10615 9722 8597 Blue 13
5 PM Mon 89 89 NW 5 10154 8947 7822 Blue 11
6 PM Mon 90 90 NW 5 10353 9354 8229 Blue 12
7 PM Mon 87 87 NW 5 9454 7467 6342 Blue 9
8 PM Mon 85 85 NW 5 8248 6667 5542 Blue 8
9 PM Mon 81 81 W 5 5839 3714 2589 Blue 4
10 PM Mon 78 78 W 3 3757 2612 1487 Blue 1
11 PM Mon 75 75 W 3 0 1125 0 Blue 0
12 Midnight Tue 72 72 W 3 0 1125 0 Blue 0
1 AM Tue 69 69 NW 3 0 1125 0 Blue 0
2 AM Tue 67 67 NW 3 0 1125 0 Blue 0
3 AM Tue 66 66 N 3 0 1125 0 Blue 0
4 AM Tue 65 65 N 3 0 1125 0 Blue 0
5 AM Tue 63 63 NE 5 0 1125 0 Blue 0
6 AM Tue 62 62 NE 5 0 1125 0 Blue 0
7 AM Tue 61 61 NE 5 0 1125 0 Blue 0
8 AM Tue 63 63 NE 5 0 1125 0 Blue 0
9 AM Tue 69 71 NE 6 0 1125 0 Blue 0
10 AM Tue 73 77 N 6 0 1125 0 Blue 0
11 AM Tue 79 84 N 6 7552 5701 4576 Blue 7
12 Noon Tue 83 89 N 6 10154 8947 7822 Blue 11
1 PM Tue 86 92 N 6 10902 10096 8971 Blue 14
2 PM Tue 90 95 NW 6 11424 10854 9729 Blue 17
3 PM Tue 91 95 NW 6 11424 10854 9729 Blue 17
4 PM Tue 92 94 NW 6 11197 10490 9365 Blue 16
5 PM Tue 92 92 NW 6 10902 10096 8971 Blue 14
6 PM Tue 93 93 W 6 11050 10293 9168 Blue 15
7 PM Tue 90 90 NW 6 10353 9354 8229 Blue 12
8 PM Tue 87 87 NW 5 9454 7467 6342 Blue 9
9 PM Tue 83 83 NW 5 7134 4774 3649 Blue 6
10 PM Tue 80 80 NW 5 4836 2612 1487 Blue 3
11 PM Tue 77 77 NW 3 0 1125 0 Blue 0
12 Midnight Wed 73 73 N 3 0 1125 0 Blue 0
1 AM Wed 69 69 N 3 0 1125 0 Blue 0
2 AM Wed 68 68 N 2 0 1125 0 Blue 0
3 AM Wed 67 67 N 2 0 1125 0 Blue 0
4 AM Wed 65 65 N 2 0 1125 0 Blue 0
5 AM Wed 63 63 N 1 0 1125 0 Blue 0
6 AM Wed 62 62 N 1 0 1125 0 Blue 0
7 AM Wed 61 61 N 1 0 1125 0 Blue 0
8 AM Wed 63 63 N 1 0 1125 0 Blue 0
9 AM Wed 69 71 N 1 0 1125 0 Blue 0
10 AM Wed 74 78 N 1 3757 2612 1487 Blue 1
11 AM Wed 80 85 N 1 8248 6667 5542 Blue 8
12 Noon Wed 85 91 N 2 10615 9722 8597 Blue 13
1 PM Wed 88 94 N 2 11197 10490 9365 Blue 16
2 PM Wed 91 96 N 2 11791 11001 9876 Blue 18
3 PM Wed 93 96 N 2 11791 11001 9876 Blue 18
4 PM Wed 94 96 N 2 11791 11001 9876 Blue 18
5 PM Wed 94 94 NW 3 11197 10490 9365 Blue 16
6 PM Wed 95 95 NW 3 11424 10854 9729 Blue 17
7 PM Wed 93 93 N 3 11050 10293 9168 Blue 15
8 PM Wed 90 90 N 5 10353 9354 8229 Blue 12
9 PM Wed 87 87 N 5 9454 7467 6342 Blue 9
10 PM Wed 84 84 N 5 7552 5701 4576 Blue 7
11 PM Wed 82 82 N 6 6736 4251 3126 Blue 5
12 Midnight Thu 79 79 N 6 4303 2612 1487 Blue 2
1 AM Thu 76 76 N 7 0 1125 0 Blue 0
2 AM Thu 74 74 NE 7 0 1125 0 Blue 0
3 AM Thu 74 74 NE 7 0 1125 0 Blue 0
4 AM Thu 72 72 NE 7 0 1125 0 Blue 0
5 AM Thu 71 71 NE 8 0 1125 0 Blue 0
6 AM Thu 70 70 NE 8 0 1125 0 Blue 0
7 AM Thu 69 69 NE 7 0 1125 0 Blue 0
8 AM Thu 70 70 NE 7 0 1125 0 Blue 0
9 AM Thu 76 78 NE 7 3757 2612 1487 Blue 1
10 AM Thu 80 83 NE 6 7134 4774 3649 Blue 6
11 AM Thu 85 90 NE 6 10353 9354 8229 Blue 12
12 Noon Thu 88 94 NE 5 11197 10490 9365 Blue 16
1 PM Thu 91 97 NE 5 12156 11148 10023 Blue 19
2 PM Thu 94 99 N 5 12879 11663 10538 Blue 21
3 PM Thu 95 98 N 3 12520 11299 10174 Blue 20
4 PM Thu 96 98 N 3 12520 11299 10174 Blue 20
5 PM Thu 96 96 N 3 11791 11001 9876 Blue 18
6 PM Thu 97 97 N 3 12156 11148 10023 Blue 19
7 PM Thu 95 95 N 3 11424 10854 9729 Blue 17
8 PM Thu 92 92 N 3 10902 10096 8971 Blue 14
9 PM Thu 89 89 N 5 10154 8947 7822 Blue 11
10 PM Thu 86 86 NE 5 9076 7054 5929 Blue 9
11 PM Thu 84 84 NE 6 7552 5701 4576 Blue 7
12 Midnight Fri 81 81 NE 6 5839 3714 2589 Blue 4
1 AM Fri 78 78 NE 7 3757 2612 1487 Blue 1
2 AM Fri 76 76 NE 8 0 1125 0 Blue 0
3 AM Fri 76 76 NE 8 0 1125 0 Blue 0
4 AM Fri 74 74 NE 9 0 1125 0 Blue 0
5 AM Fri 73 73 E 9 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