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

Station:

KTUS

Date/Time:

21 SEP 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 81 81 S 1 2 0 1125 0 Blue 0
1 AM Tue 79 79 E 2 2 0 1125 0 Blue 0
2 AM Tue 78 78 E 2 3 0 1125 0 Blue 0
3 AM Tue 77 77 SE 2 2 0 1125 0 Blue 0
4 AM Tue 76 76 SSE 2 2 0 1125 0 Blue 0
5 AM Tue 75 75 SSE 2 2 0 1125 0 Blue 0
6 AM Tue 74 74 SE 2 3 0 1125 0 Blue 0
7 AM Tue 74 74 SE 2 2 0 1125 0 Blue 0
8 AM Tue 79 80 SE 2 2 0 1125 0 Blue 0
9 AM Tue 85 87 E 2 3 0 1125 0 Blue 0
10 AM Tue 90 94 E 2 4 1151 1151 26 White 0
11 AM Tue 93 98 E 2 5 1151 1151 26 White 0
12 Noon Tue 95 101 ESE 3 5 1151 1151 26 White 0
1 PM Tue 97 103 W 3 5 1151 1151 26 White 0
2 PM Tue 99 104 WNW 2 6 1151 1151 26 White 0
3 PM Tue 99 103 WNW 3 8 1151 1151 26 White 0
4 PM Tue 100 102 WNW 3 8 1151 1151 26 White 0
5 PM Tue 100 100 WNW 3 6 1151 1151 26 White 0
6 PM Tue 97 97 WNW 2 5 1151 1151 26 White 0
7 PM Tue 94 94 W 2 3 1151 1151 26 White 0
8 PM Tue 90 90 W 2 3 0 1125 0 Blue 0
9 PM Tue 87 87 WSW 2 4 0 1125 0 Blue 0
10 PM Tue 86 86 S 1 2 0 1125 0 Blue 0
11 PM Tue 84 84 SW 1 1 0 1125 0 Blue 0
12 Midnight Wed 83 83 NW 1 1 0 1125 0 Blue 0
1 AM Wed 82 82 SSW 2 3 0 1125 0 Blue 0
2 AM Wed 79 79 SE 2 2 0 1125 0 Blue 0
3 AM Wed 79 79 SE 2 3 0 1125 0 Blue 0
4 AM Wed 77 77 ESE 4 6 0 1125 0 Blue 0
5 AM Wed 76 76 E 5 5 0 1125 0 Blue 0
6 AM Wed 76 76 E 5 6 0 1125 0 Blue 0
7 AM Wed 76 76 ESE 6 10 0 1125 0 Blue 0
8 AM Wed 81 82 E 9 11 0 1125 0 Blue 0
9 AM Wed 86 88 E 10 12 0 1125 0 Blue 0
10 AM Wed 90 94 E 11 14 1151 1151 26 White 0
11 AM Wed 93 98 E 11 17 1151 1151 26 White 0
12 Noon Wed 96 102 E 10 16 1151 1151 26 White 0
1 PM Wed 98 104 E 9 13 1151 1151 26 White 0
2 PM Wed 100 105 E 8 11 1167 1167 42 White 0
3 PM Wed 101 105 E 6 10 1167 1167 42 White 0
4 PM Wed 102 104 E 4 8 1151 1151 26 White 0
5 PM Wed 101 101 E 3 6 1151 1151 26 White 0
6 PM Wed 99 99 E 2 5 1151 1151 26 White 0
7 PM Wed 95 95 NE 2 4 1151 1151 26 White 0
8 PM Wed 92 92 NNE 2 3 0 1125 0 Blue 0
9 PM Wed 90 90 NE 2 2 0 1125 0 Blue 0
10 PM Wed 88 88 NE 1 2 0 1125 0 Blue 0
11 PM Wed 86 86 NE 1 2 0 1125 0 Blue 0
12 Midnight Thu 84 84 ENE 1 2 0 1125 0 Blue 0
1 AM Thu 82 82 E 2 3 0 1125 0 Blue 0
2 AM Thu 81 81 ESE 2 3 0 1125 0 Blue 0
3 AM Thu 80 80 ESE 2 3 0 1125 0 Blue 0
4 AM Thu 79 79 ESE 2 3 0 1125 0 Blue 0
5 AM Thu 79 79 ESE 2 3 0 1125 0 Blue 0
6 AM Thu 79 79 ESE 2 3 0 1125 0 Blue 0
7 AM Thu 79 79 E 3 4 0 1125 0 Blue 0
8 AM Thu 81 81 E 3 5 0 1125 0 Blue 0
9 AM Thu 84 85 ESE 4 6 0 1125 0 Blue 0
10 AM Thu 88 90 ESE 4 8 0 1125 0 Blue 0
11 AM Thu 92 95 ESE 5 9 1151 1151 26 White 0
12 Noon Thu 94 98 SSE 5 10 1151 1151 26 White 0
1 PM Thu 96 100 SSW 5 12 1151 1151 26 White 0
2 PM Thu 97 100 WSW 5 13 1151 1151 26 White 0
3 PM Thu 98 100 WSW 5 14 1151 1151 26 White 0
4 PM Thu 98 99 WSW 6 14 1151 1151 26 White 0
5 PM Thu 97 97 WSW 6 14 1151 1151 26 White 0
6 PM Thu 95 95 WSW 6 13 1151 1151 26 White 0
7 PM Thu 93 93 WSW 6 12 0 1125 0 Blue 0
8 PM Thu 90 90 WSW 5 11 0 1125 0 Blue 0
9 PM Thu 88 88 WSW 4 11 0 1125 0 Blue 0
10 PM Thu 86 86 SW 3 11 0 1125 0 Blue 0
11 PM Thu 85 85 SW 2 10 0 1125 0 Blue 0
12 Midnight Fri 84 84 SW 2 8 0 1125 0 Blue 0
1 AM Fri 82 82 SSW 2 5 0 1125 0 Blue 0
2 AM Fri 81 81 SSW 2 4 0 1125 0 Blue 0
3 AM Fri 80 80 S 2 4 0 1125 0 Blue 0
4 AM Fri 79 79 SE 2 4 0 1125 0 Blue 0
5 AM Fri 78 78 ESE 2 4 0 1125 0 Blue 0
6 AM Fri 78 78 ESE 2 4 0 1125 0 Blue 0
7 AM Fri 78 78 SE 2 4 0 1125 0 Blue 0
8 AM Fri 80 80 SE 2 5 0 1125 0 Blue 0
9 AM Fri 83 84 SSE 3 8 0 1125 0 Blue 0
10 AM Fri 87 90 S 3 10 0 1125 0 Blue 0
11 AM Fri 90 94 SSW 4 11 1151 1151 26 White 0
12 Noon Fri 92 97 SW 4 11 1151 1151 26 White 0
1 PM Fri 94 99 W 4 11 1151 1151 26 White 0
2 PM Fri 95 99 WNW 4 11 1151 1151 26 White 0
3 PM Fri 97 100 WNW 4 11 1151 1151 26 White 0
4 PM Fri 97 99 WNW 5 10 1151 1151 26 White 0
5 PM Fri 97 97 WNW 5 10 1151 1151 26 White 0
6 PM Fri 95 95 W 5 10 1151 1151 26 White 0
7 PM Fri 91 91 SW 5 10 0 1125 0 Blue 0
8 PM Fri 88 88 SSW 4 9 0 1125 0 Blue 0
9 PM Fri 86 86 SW 3 8 0 1125 0 Blue 0
10 PM Fri 84 84 W 3 5 0 1125 0 Blue 0
11 PM Fri 82 82 W 2 4 0 1125 0 Blue 0
12 Midnight Sat 80 80 WSW 2 4 0 1125 0 Blue 0
1 AM Sat 79 79 S 2 4 0 1125 0 Blue 0
2 AM Sat 78 78 SE 2 4 0 1125 0 Blue 0
3 AM Sat 77 77 ESE 2 4 0 1125 0 Blue 0
4 AM Sat 75 75 ESE 2 4 0 1125 0 Blue 0
5 AM Sat 75 75 E 2 4 0 1125 0 Blue 0
6 AM Sat 75 75 E 2 4 0 1125 0 Blue 0
7 AM Sat 77 77 ESE 2 4 0 1125 0 Blue 0
8 AM Sat 79 79 ESE 2 4 0 1125 0 Blue 0
9 AM Sat 82 84 ESE 3 5 0 1125 0 Blue 0
10 AM Sat 86 89 E 3 6 0 1125 0 Blue 0
11 AM Sat 89 94 E 4 8 1151 1151 26 White 0
12 Noon Sat 92 98 ESE 4 8 1151 1151 26 White 0
1 PM Sat 94 100 SSE 3 8 1151 1151 26 White 0
2 PM Sat 96 101 S 3 8 1151 1151 26 White 0
3 PM Sat 97 100 SSW 3 8 1151 1151 26 White 0
4 PM Sat 97 99 W 3 6 1151 1151 26 White 0
5 PM Sat 96 96 W 3 6 1151 1151 26 White 0
6 PM Sat 94 94 W 3 5 1151 1151 26 White 0
7 PM Sat 92 92 W 2 4 0 1125 0 Blue 0
8 PM Sat 90 90 W 2 4 0 1125 0 Blue 0
9 PM Sat 88 88 W 2 4 0 1125 0 Blue 0
10 PM Sat 86 86 SW 3 5 0 1125 0 Blue 0
11 PM Sat 84 84 SW 3 6 0 1125 0 Blue 0
12 Midnight Sun 82 82 SSW 3 8 0 1125 0 Blue 0
1 AM Sun 81 81 SSW 3 8 0 1125 0 Blue 0
2 AM Sun 80 80 S 3 8 0 1125 0 Blue 0
3 AM Sun 79 79 S 3 8 0 1125 0 Blue 0
4 AM Sun 78 78 SSE 2 6 0 1125 0 Blue 0
5 AM Sun 77 77 SSE 2 5 0 1125 0 Blue 0
6 AM Sun 77 77 SE 2 4 0 1125 0 Blue 0
7 AM Sun 77 77 ESE 3 4 0 1125 0 Blue 0
8 AM Sun 79 79 E 3 4 0 1125 0 Blue 0
9 AM Sun 82 84 E 3 4 0 1125 0 Blue 0
10 AM Sun 86 89 ESE 3 5 0 1125 0 Blue 0
11 AM Sun 89 94 ESE 3 6 1151 1151 26 White 0
12 Noon Sun 92 97 SSE 3 8 1151 1151 26 White 0
1 PM Sun 94 100 SW 3 9 1151 1151 26 White 0
2 PM Sun 95 100 WSW 3 10 1151 1151 26 White 0
3 PM Sun 96 99 WSW 4 11 1151 1151 26 White 0
4 PM Sun 97 99 WSW 5 11 1151 1151 26 White 0
5 PM Sun 96 96 WSW 5 11 1151 1151 26 White 0
6 PM Sun 94 94 WSW 4 9 1151 1151 26 White 0
7 PM Sun 92 92 WSW 3 8 0 1125 0 Blue 0
8 PM Sun 89 89 WSW 2 5 0 1125 0 Blue 0
9 PM Sun 87 87 WSW 2 5 0 1125 0 Blue 0
10 PM Sun 86 86 WSW 3 5 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 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]