Detailed Predictions for: Rainbow Valley
Launch Lat, Long, Altitude (f): 33.18816, -112.37519, 1125
LZ Altitude (f): 80
Sounding

Station:

KTUS

Date/Time:

18 MAY 2021

Temp/Wind data from:

NOAA Digital Forecast

Site Forecasts
Time
(Local)
High
Temp

Puddle
Temp

Wind
(mph)
Wind
Gust
Thermal
Ceiling

(ft)
Soaring
Ceiling

(ft)
Above
Launch

(ft)
Thermal
Type
Thermal
Index

(F)
12 Midnight Tue 76 76 SW 5 10 2778 2470 1345 Blue 3
1 AM Tue 74 74 SSW 5 10 2562 2470 1345 Blue 1
2 AM Tue 72 72 SSW 5 10 0 1125 0 Blue 0
3 AM Tue 70 70 SE 3 6 0 1125 0 Blue 0
4 AM Tue 69 69 E 2 5 0 1125 0 Blue 0
5 AM Tue 68 68 E 2 5 0 1125 0 Blue 0
6 AM Tue 67 67 ESE 2 4 0 1125 0 Blue 0
7 AM Tue 71 71 SSE 2 5 0 1125 0 Blue 0
8 AM Tue 77 79 SW 2 6 3694 2773 1648 Blue 6
9 AM Tue 80 84 WSW 4 8 6890 4476 3351 Blue 11
10 AM Tue 84 90 W 5 10 13324 9957 8832 Blue 16
11 AM Tue 87 94 WSW 8 12 15710 13708 12583 Blue 20
12 Noon Tue 89 97 WSW 10 13 16182 15440 14315 Blue 23
1 PM Tue 91 99 WSW 12 16 16499 16011 14886 Blue 25
2 PM Tue 93 100 W 13 19 17636 16119 14994 Blue 26
3 PM Tue 94 99 WSW 14 17 16499 16011 14886 Blue 25
4 PM Tue 95 98 WSW 12 17 16340 15903 14778 Blue 24
5 PM Tue 95 96 WSW 13 19 16067 14672 13547 Blue 22
6 PM Tue 95 95 WSW 12 16 15959 14049 12924 Blue 21
7 PM Tue 93 93 WSW 10 14 15145 12971 11846 Blue 19
8 PM Tue 89 89 SW 8 13 12407 9304 8179 Blue 16
9 PM Tue 86 86 SW 9 14 9484 5181 4056 Blue 13
10 PM Tue 84 84 SW 12 17 6890 4476 3351 Blue 11
11 PM Tue 83 83 SW 11 14 5219 4072 2947 Blue 10
12 Midnight Wed 81 81 SW 8 13 4518 3245 2120 Blue 8
1 AM Wed 78 78 SW 5 10 3272 2665 1540 Blue 5
2 AM Wed 77 77 NNW 4 8 2886 2557 1432 Blue 4
3 AM Wed 74 74 NNE 2 6 2562 2470 1345 Blue 1
4 AM Wed 73 73 E 2 5 0 1125 0 Blue 0
5 AM Wed 72 72 ESE 2 4 0 1125 0 Blue 0
6 AM Wed 72 72 SE 2 5 0 1125 0 Blue 0
7 AM Wed 75 75 SE 2 4 2670 2470 1345 Blue 2
8 AM Wed 81 83 SE 2 5 5219 4072 2947 Blue 10
9 AM Wed 85 89 SSW 2 6 12407 9304 8179 Blue 16
10 AM Wed 89 95 SW 3 9 15959 14049 12924 Blue 21
11 AM Wed 92 100 WSW 5 11 17636 16119 14994 Blue 26
12 Noon Wed 95 104 SW 6 12 20594 18070 16945 Blue 30
1 PM Wed 97 105 WSW 9 13 21355 18545 17420 Blue 31
2 PM Wed 98 105 WSW 10 16 21355 18545 17420 Blue 31
3 PM Wed 99 104 WSW 11 17 20594 18070 16945 Blue 30
4 PM Wed 100 103 SW 13 19 19463 16975 15850 Blue 29
5 PM Wed 99 100 SW 13 19 17636 16119 14994 Blue 26
6 PM Wed 97 97 SW 13 19 16182 15440 14315 Blue 23
7 PM Wed 94 94 SW 11 18 15710 13708 12583 Blue 20
8 PM Wed 91 91 SW 10 17 13856 10983 9858 Blue 17
9 PM Wed 88 88 SW 8 14 11362 8212 7087 Blue 15
10 PM Wed 85 85 SW 6 12 8542 4874 3749 Blue 12
11 PM Wed 82 82 SW 4 10 4911 3662 2537 Blue 9
12 Midnight Thu 80 80 SW 3 8 4109 2880 1755 Blue 7
1 AM Thu 78 78 SSW 2 6 3272 2665 1540 Blue 5
2 AM Thu 76 76 SSW 2 5 2778 2470 1345 Blue 3
3 AM Thu 74 74 S 2 4 2562 2470 1345 Blue 1
4 AM Thu 72 72 SSE 2 4 0 1125 0 Blue 0
5 AM Thu 71 71 SE 2 5 0 1125 0 Blue 0
6 AM Thu 72 72 SSE 2 6 0 1125 0 Blue 0
7 AM Thu 75 75 SSE 3 8 2670 2470 1345 Blue 2
8 AM Thu 79 80 S 4 10 4109 2880 1755 Blue 7
9 AM Thu 83 85 S 5 12 8542 4874 3749 Blue 12
10 AM Thu 87 91 SSW 8 16 13856 10983 9858 Blue 17
11 AM Thu 91 95 SW 9 18 15959 14049 12924 Blue 21
12 Noon Thu 93 98 SW 10 19 16340 15903 14778 Blue 24
1 PM Thu 94 100 SW 10 19 17636 16119 14994 Blue 26
2 PM Thu 95 100 SW 11 19 17636 16119 14994 Blue 26
3 PM Thu 96 99 SW 12 20 16499 16011 14886 Blue 25
4 PM Thu 96 97 SW 13 20 16182 15440 14315 Blue 23
5 PM Thu 95 95 SW 14 20 15959 14049 12924 Blue 21
6 PM Thu 93 93 SW 13 19 15145 12971 11846 Blue 19
7 PM Thu 91 91 SW 12 17 13856 10983 9858 Blue 17
8 PM Thu 88 88 SW 11 16 11362 8212 7087 Blue 15
9 PM Thu 86 86 SW 10 17 9484 5181 4056 Blue 13
10 PM Thu 83 83 SW 10 17 5219 4072 2947 Blue 10
11 PM Thu 81 81 SW 9 18 4518 3245 2120 Blue 8
12 Midnight Fri 79 79 SW 8 17 3694 2773 1648 Blue 6
1 AM Fri 77 77 SW 8 14 2886 2557 1432 Blue 4
2 AM Fri 75 75 SW 6 13 2670 2470 1345 Blue 2
3 AM Fri 73 73 SW 5 12 0 1125 0 Blue 0
4 AM Fri 70 70 SW 5 12 0 1125 0 Blue 0
5 AM Fri 69 69 SSW 5 12 0 1125 0 Blue 0
6 AM Fri 69 69 SW 5 12 0 1125 0 Blue 0
7 AM Fri 70 70 SW 6 12 0 1125 0 Blue 0
8 AM Fri 72 73 SW 8 12 0 1125 0 Blue 0
9 AM Fri 75 78 SW 9 12 3272 2665 1540 Blue 5
10 AM Fri 78 83 SW 9 13 5219 4072 2947 Blue 10
11 AM Fri 81 88 SW 10 14 11362 8212 7087 Blue 15
12 Noon Fri 83 91 SW 11 16 13856 10983 9858 Blue 17
1 PM Fri 85 93 WSW 12 18 15145 12971 11846 Blue 19
2 PM Fri 86 93 WSW 13 19 15145 12971 11846 Blue 19
3 PM Fri 87 92 WSW 14 20 14273 12044 10919 Blue 18
4 PM Fri 87 90 WSW 14 20 13324 9957 8832 Blue 16
5 PM Fri 86 87 WSW 14 20 10143 6530 5405 Blue 14
6 PM Fri 84 84 WSW 12 19 6890 4476 3351 Blue 11
7 PM Fri 81 81 W 9 17 4518 3245 2120 Blue 8
8 PM Fri 78 78 W 6 14 3272 2665 1540 Blue 5
9 PM Fri 75 75 W 5 13 2670 2470 1345 Blue 2
10 PM Fri 72 72 WSW 4 12 0 1125 0 Blue 0
11 PM Fri 70 70 WSW 3 11 0 1125 0 Blue 0
12 Midnight Sat 68 68 WSW 2 10 0 1125 0 Blue 0
1 AM Sat 67 67 SW 2 8 0 1125 0 Blue 0
2 AM Sat 65 65 SW 2 6 0 1125 0 Blue 0
3 AM Sat 62 62 SW 2 5 0 1125 0 Blue 0
4 AM Sat 60 60 SSW 2 5 0 1125 0 Blue 0
5 AM Sat 59 59 SSW 2 5 0 1125 0 Blue 0
6 AM Sat 61 61 SSW 2 5 0 1125 0 Blue 0
7 AM Sat 64 64 SSW 3 5 0 1125 0 Blue 0
8 AM Sat 68 70 SSW 3 5 0 1125 0 Blue 0
9 AM Sat 72 76 SW 3 5 2778 2470 1345 Blue 3
10 AM Sat 76 82 SW 4 6 4911 3662 2537 Blue 9
11 AM Sat 80 87 SW 4 8 10143 6530 5405 Blue 14
12 Noon Sat 83 91 SW 5 10 13856 10983 9858 Blue 17
1 PM Sat 85 93 WSW 5 11 15145 12971 11846 Blue 19
2 PM Sat 86 93 WSW 6 13 15145 12971 11846 Blue 19
3 PM Sat 88 93 WSW 8 14 15145 12971 11846 Blue 19
4 PM Sat 88 91 WSW 9 14 13856 10983 9858 Blue 17
5 PM Sat 88 89 WSW 10 14 12407 9304 8179 Blue 16
6 PM Sat 86 86 WSW 9 13 9484 5181 4056 Blue 13
7 PM Sat 82 82 W 8 12 4911 3662 2537 Blue 9
8 PM Sat 79 79 W 5 11 3694 2773 1648 Blue 6
9 PM Sat 76 76 W 4 10 2778 2470 1345 Blue 3
10 PM Sat 74 74 WSW 3 10 2562 2470 1345 Blue 1
11 PM Sat 72 72 WSW 3 9 0 1125 0 Blue 0
12 Midnight Sun 70 70 SW 3 8 0 1125 0 Blue 0
1 AM Sun 68 68 SW 2 5 0 1125 0 Blue 0
2 AM Sun 66 66 SSW 2 4 0 1125 0 Blue 0
3 AM Sun 64 64 SSW 2 4 0 1125 0 Blue 0
4 AM Sun 62 62 SSW 2 4 0 1125 0 Blue 0
5 AM Sun 62 62 S 2 4 0 1125 0 Blue 0
6 AM Sun 63 63 S 2 4 0 1125 0 Blue 0
7 AM Sun 66 66 ESE 2 4 0 1125 0 Blue 0
8 AM Sun 70 72 E 2 4 0 1125 0 Blue 0
9 AM Sun 75 79 E 2 5 3694 2773 1648 Blue 6
10 AM Sun 80 86 ENE 2 5 9484 5181 4056 Blue 13
11 AM Sun 85 93 NE 2 6 15145 12971 11846 Blue 19
12 Noon Sun 88 97 NNE 2 8 16182 15440 14315 Blue 23
1 PM Sun 89 98 NW 3 8 16340 15903 14778 Blue 24
2 PM Sun 90 98 W 3 9 16340 15903 14778 Blue 24
3 PM Sun 92 98 W 4 10 16340 15903 14778 Blue 24
4 PM Sun 92 95 W 5 10 15959 14049 12924 Blue 21
5 PM Sun 92 93 W 5 10 15145 12971 11846 Blue 19
6 PM Sun 90 90 W 5 9 13324 9957 8832 Blue 16
7 PM Sun 87 87 W 4 8 10143 6530 5405 Blue 14
8 PM Sun 83 83 W 3 6 5219 4072 2947 Blue 10
9 PM Sun 80 80 W 3 6 4109 2880 1755 Blue 7
10 PM Sun 77 77 W 2 5 2886 2557 1432 Blue 4

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 or WeatherAPI.com website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the National Weather Service or WeatherAPI.com 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 or WeatherAPI.com website.

Wind Gust: This estimate is taken from the National Weather Service or WeatherAPI.com 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 [email protected]