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

Station:

KTUS

Date/Time:

19 NOV 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)
5 AM Sun 48 48 NE 6 0 1125 0 Blue 0
6 AM Sun 48 48 NE 6 0 1125 0 Blue 0
7 AM Sun 48 48 E 6 0 1125 0 Blue 0
8 AM Sun 50 50 E 7 0 1125 0 Blue 0
9 AM Sun 58 59 E 9 1152 1152 27 White 0
10 AM Sun 64 66 E 10 2435 2435 1310 White 0
11 AM Sun 68 71 E 12 2910 2757 1632 Blue 11
12 Noon Sun 73 76 E 12 3357 3166 2041 Blue 16
1 PM Sun 75 78 E 12 3823 3290 2165 Blue 18
2 PM Sun 76 78 NE 10 3823 3290 2165 Blue 18
3 PM Sun 78 79 NE 8 3902 3352 2227 Blue 19
4 PM Sun 78 78 N 6 3823 3290 2165 Blue 18
5 PM Sun 75 75 N 5 3295 3036 1911 Blue 15
6 PM Sun 72 72 N 3 3054 2806 1681 Blue 12
7 PM Sun 69 69 N 3 2809 2697 1572 Blue 9
8 PM Sun 66 66 N 3 2435 2435 1310 White 0
9 PM Sun 63 63 N 3 1777 1777 652 White 0
10 PM Sun 61 61 N 3 1337 1337 212 White 0
11 PM Sun 60 60 NE 3 1152 1152 27 White 0
12 Midnight Mon 57 57 NE 3 1152 1152 27 White 0
1 AM Mon 56 56 NE 3 1152 1152 27 White 0
2 AM Mon 55 55 E 3 1152 1152 27 White 0
3 AM Mon 54 54 E 3 1152 1152 27 White 0
4 AM Mon 52 52 E 3 0 1125 0 Blue 0
5 AM Mon 52 52 E 5 0 1125 0 Blue 0
6 AM Mon 49 49 E 5 0 1125 0 Blue 0
7 AM Mon 49 49 E 5 0 1125 0 Blue 0
8 AM Mon 50 50 E 5 0 1125 0 Blue 0
9 AM Mon 57 57 E 6 1152 1152 27 White 0
10 AM Mon 66 67 E 7 2647 2639 1514 White 7
11 AM Mon 69 71 E 7 2910 2757 1632 Blue 11
12 Noon Mon 75 77 E 6 3646 3228 2103 Blue 17
1 PM Mon 78 80 E 5 4542 3618 2493 Blue 20
2 PM Mon 78 79 E 3 3902 3352 2227 Blue 19
3 PM Mon 78 79 NE 3 3902 3352 2227 Blue 19
4 PM Mon 78 78 N 3 3823 3290 2165 Blue 18
5 PM Mon 77 77 NW 3 3646 3228 2103 Blue 17
6 PM Mon 74 74 NW 3 3232 2907 1782 Blue 14
7 PM Mon 71 71 NW 3 2910 2757 1632 Blue 11
8 PM Mon 67 67 NW 3 2647 2639 1514 White 7
9 PM Mon 64 64 W 2 1997 1997 872 White 0
10 PM Mon 62 62 W 2 1557 1557 432 White 0
11 PM Mon 60 60 W 1 1152 1152 27 White 0
12 Midnight Tue 58 58 W 1 1152 1152 27 White 0
1 AM Tue 57 57 S 1 1152 1152 27 White 0
2 AM Tue 55 55 S 1 1152 1152 27 White 0
3 AM Tue 54 54 S 1 1152 1152 27 White 0
4 AM Tue 53 53 SE 1 1152 1152 27 White 0
5 AM Tue 52 52 E 2 0 1125 0 Blue 0
6 AM Tue 50 50 E 2 0 1125 0 Blue 0
7 AM Tue 50 50 E 3 0 1125 0 Blue 0
8 AM Tue 52 52 E 3 0 1125 0 Blue 0
9 AM Tue 57 57 E 5 1152 1152 27 White 0
10 AM Tue 64 65 E 5 2216 2216 1091 White 0
11 AM Tue 70 72 E 6 3054 2806 1681 Blue 12
12 Noon Tue 75 77 E 6 3646 3228 2103 Blue 17
1 PM Tue 78 80 NE 6 4542 3618 2493 Blue 20
2 PM Tue 81 82 N 6 5439 3895 2770 Blue 22
3 PM Tue 82 83 N 6 5597 4442 3317 Blue 23
4 PM Tue 83 83 NW 5 5597 4442 3317 Blue 23
5 PM Tue 82 82 NW 5 5439 3895 2770 Blue 22
6 PM Tue 79 79 NW 5 3902 3352 2227 Blue 19
7 PM Tue 75 75 NW 3 3295 3036 1911 Blue 15
8 PM Tue 71 71 N 3 2910 2757 1632 Blue 11
9 PM Tue 68 68 N 3 2759 2668 1543 Blue 8
10 PM Tue 67 67 NE 3 2647 2639 1514 White 7
11 PM Tue 65 65 NE 3 2216 2216 1091 White 0
12 Midnight Wed 64 64 NE 3 1997 1997 872 White 0
1 AM Wed 62 62 NE 5 1557 1557 432 White 0
2 AM Wed 61 61 NE 6 1337 1337 212 White 0
3 AM Wed 60 60 NE 7 1152 1152 27 White 0
4 AM Wed 59 59 E 7 1152 1152 27 White 0
5 AM Wed 58 58 E 8 1152 1152 27 White 0
6 AM Wed 56 56 E 9 1152 1152 27 White 0
7 AM Wed 55 55 E 10 1152 1152 27 White 0
8 AM Wed 57 57 E 10 1152 1152 27 White 0
9 AM Wed 62 62 E 12 1557 1557 432 White 0
10 AM Wed 69 70 E 12 2859 2727 1602 Blue 10
11 AM Wed 76 78 E 12 3823 3290 2165 Blue 18
12 Noon Wed 81 84 E 10 5755 5260 4135 Blue 24
1 PM Wed 83 85 E 9 6574 5417 4292 White 25
2 PM Wed 85 87 E 8 6999 5731 4606 White 26
3 PM Wed 86 87 NE 7 6999 5731 4606 White 26
4 PM Wed 86 86 NE 6 6787 5574 4449 White 25
5 PM Wed 85 85 NE 5 6574 5417 4292 White 25
6 PM Wed 82 82 NE 5 5439 3895 2770 Blue 22
7 PM Wed 77 77 NE 5 3646 3228 2103 Blue 17
8 PM Wed 73 73 NE 5 3170 2856 1731 Blue 13
9 PM Wed 70 70 NE 5 2859 2727 1602 Blue 10
10 PM Wed 68 68 NE 6 2759 2668 1543 Blue 8
11 PM Wed 67 67 NE 6 2647 2639 1514 White 7
12 Midnight Thu 65 65 NE 6 2216 2216 1091 White 0
1 AM Thu 63 63 E 6 1777 1777 652 White 0
2 AM Thu 62 62 E 6 1557 1557 432 White 0
3 AM Thu 61 61 E 7 1337 1337 212 White 0
4 AM Thu 60 60 E 7 1152 1152 27 White 0
5 AM Thu 59 59 E 7 1152 1152 27 White 0
6 AM Thu 57 57 E 8 1152 1152 27 White 0
7 AM Thu 56 56 E 8 1152 1152 27 White 0
8 AM Thu 58 58 E 9 1152 1152 27 White 0
9 AM Thu 63 64 E 9 1997 1997 872 White 0
10 AM Thu 70 72 E 10 3054 2806 1681 Blue 12
11 AM Thu 77 80 E 10 4542 3618 2493 Blue 20
12 Noon Thu 82 85 E 9 6574 5417 4292 White 25
1 PM Thu 85 88 E 8 7212 6007 4882 White 27
2 PM Thu 87 89 NE 7 7423 6719 5594 White 28
3 PM Thu 87 88 NE 6 7212 6007 4882 White 27
4 PM Thu 86 86 NE 5 6787 5574 4449 White 25
5 PM Thu 84 84 NE 3 5755 5260 4135 Blue 24
6 PM Thu 81 81 NE 2 5281 3816 2691 Blue 21
7 PM Thu 77 77 NE 2 3646 3228 2103 Blue 17
8 PM Thu 73 73 NE 2 3170 2856 1731 Blue 13
9 PM Thu 70 70 E 2 2859 2727 1602 Blue 10
10 PM Thu 68 68 E 3 2759 2668 1543 Blue 8
11 PM Thu 67 67 E 3 2647 2639 1514 White 7
12 Midnight Fri 65 65 E 3 2216 2216 1091 White 0
1 AM Fri 63 63 E 3 1777 1777 652 White 0
2 AM Fri 62 62 E 3 1557 1557 432 White 0
3 AM Fri 61 61 E 3 1337 1337 212 White 0
4 AM Fri 60 60 E 3 1152 1152 27 White 0
5 AM Fri 59 59 E 5 1152 1152 27 White 0
6 AM Fri 57 57 E 5 1152 1152 27 White 0
7 AM Fri 56 56 E 5 1152 1152 27 White 0
8 AM Fri 58 58 E 5 1152 1152 27 White 0
9 AM Fri 63 64 E 3 1997 1997 872 White 0
10 AM Fri 70 72 E 3 3054 2806 1681 Blue 12
11 AM Fri 77 79 E 3 3902 3352 2227 Blue 19
12 Noon Fri 81 84 E 3 5755 5260 4135 Blue 24
1 PM Fri 84 87 NE 2 6999 5731 4606 White 26
2 PM Fri 86 88 NE 2 7212 6007 4882 White 27
3 PM Fri 86 87 N 2 6999 5731 4606 White 26
4 PM Fri 85 85 N 1 6574 5417 4292 White 25
5 PM Fri 83 83 NW 1 5597 4442 3317 Blue 23
6 PM Fri 80 80 N 1 4542 3618 2493 Blue 20
7 PM Fri 76 76 N 1 3357 3166 2041 Blue 16
8 PM Fri 72 72 NE 1 3054 2806 1681 Blue 12
9 PM Fri 69 69 E 1 2809 2697 1572 Blue 9
10 PM Fri 67 67 SE 1 2647 2639 1514 White 7
11 PM Fri 65 65 SE 1 2216 2216 1091 White 0
12 Midnight Sat 64 64 SE 1 1997 1997 872 White 0
1 AM Sat 62 62 SE 1 1557 1557 432 White 0
2 AM Sat 61 61 E 2 1337 1337 212 White 0
3 AM Sat 60 60 E 2 1152 1152 27 White 0
4 AM Sat 59 59 E 2 1152 1152 27 White 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