Detailed Predictions for: Sweetwater
Launch Lat, Long, Altitude (f): 38.394, -119.370, 9500
LZ Altitude (f): 7400
Sounding

Station:

 KVBG

Date/Time:

 11 DEC 2023

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 Mon 31 31 W 19 29 4997 9500 0 Blue 0
1 AM Mon 30 30 W 21 32 4997 9500 0 Blue 0
2 AM Mon 30 30 W 21 32 4997 9500 0 Blue 0
3 AM Mon 28 28 W 21 32 4997 9500 0 Blue 0
4 AM Mon 28 28 W 19 29 4997 9500 0 Blue 0
5 AM Mon 27 27 W 19 29 4997 9500 0 Blue 0
6 AM Mon 25 25 W 19 29 4997 9500 0 Blue 0
7 AM Mon 27 27 W 16 23 4997 9500 0 Blue 0
8 AM Mon 29 29 W 16 23 4997 9500 0 Blue 0
9 AM Mon 34 34 W 16 23 4997 9500 0 Blue 0
10 AM Mon 37 37 W 13 20 5604 9500 0 Blue 0
11 AM Mon 41 42 W 13 20 8382 9500 0 Blue 0
12 Noon Mon 42 43 W 13 20 8893 9500 0 Blue 0
1 PM Mon 43 43 W 12 18 8893 9500 0 Blue 0
2 PM Mon 44 44 W 12 18 9392 9500 0 Blue 0
3 PM Mon 42 42 W 12 18 8382 9500 0 Blue 0
4 PM Mon 39 39 WNW 6 10 6766 9500 0 Blue 0
5 PM Mon 36 36 WNW 6 10 4997 9500 0 Blue 0
6 PM Mon 32 32 WNW 6 10 4997 9500 0 Blue 0
7 PM Mon 31 31 WNW 5 6 4997 9500 0 Blue 0
8 PM Mon 28 28 WNW 5 6 4997 9500 0 Blue 0
9 PM Mon 27 27 WNW 5 6 4997 9500 0 Blue 0
10 PM Mon 26 26 WSW 4 6 4997 9500 0 Blue 0
11 PM Mon 26 26 WSW 4 6 4997 9500 0 Blue 0
12 Midnight Tue 25 25 WSW 4 6 4997 9500 0 Blue 0
1 AM Tue 26 26 WSW 5 5 4997 9500 0 Blue 0
2 AM Tue 24 24 WSW 5 5 4997 9500 0 Blue 0
3 AM Tue 23 23 WSW 5 5 4997 9500 0 Blue 0
4 AM Tue 23 23 NNW 5 9 4997 9500 0 Blue 0
5 AM Tue 21 21 NNW 5 9 4997 9500 0 Blue 0
6 AM Tue 19 19 NNW 5 9 4997 9500 0 Blue 0
7 AM Tue 20 20 WNW 5 5 4997 9500 0 Blue 0
8 AM Tue 22 22 WNW 5 5 4997 9500 0 Blue 0
9 AM Tue 26 26 WNW 5 5 4997 9500 0 Blue 0
10 AM Tue 28 29 NNW 10 16 4997 9500 0 Blue 0
11 AM Tue 30 32 NNW 10 16 4997 9500 0 Blue 0
12 Noon Tue 31 33 NNW 10 16 4997 9500 0 Blue 0
1 PM Tue 31 32 NNE 9 13 4997 9500 0 Blue 0
2 PM Tue 30 31 NNE 9 13 4997 9500 0 Blue 0
3 PM Tue 28 28 NNE 9 13 4997 9500 0 Blue 0
4 PM Tue 26 26 NE 12 19 4997 9500 0 Blue 0
5 PM Tue 23 23 NE 12 19 4997 9500 0 Blue 0
6 PM Tue 21 21 NE 12 19 4997 9500 0 Blue 0
7 PM Tue 19 19 ENE 14 21 4997 9500 0 Blue 0
8 PM Tue 18 18 ENE 14 21 4997 9500 0 Blue 0
9 PM Tue 18 18 ENE 14 21 4997 9500 0 Blue 0
10 PM Tue 18 18 SSE 16 24 4997 9500 0 Blue 0
11 PM Tue 18 18 SSE 16 24 4997 9500 0 Blue 0
12 Midnight Wed 19 19 SSE 16 24 4997 9500 0 Blue 0
1 AM Wed 19 19 S 14 23 4997 9500 0 Blue 0
2 AM Wed 19 19 S 14 23 4997 9500 0 Blue 0
3 AM Wed 18 18 S 14 23 4997 9500 0 Blue 0
4 AM Wed 18 18 S 13 20 4997 9500 0 Blue 0
5 AM Wed 18 18 S 13 20 4997 9500 0 Blue 0
6 AM Wed 19 19 S 13 20 4997 9500 0 Blue 0
7 AM Wed 19 19 S 12 19 4997 9500 0 Blue 0
8 AM Wed 22 22 S 12 19 4997 9500 0 Blue 0
9 AM Wed 26 26 S 12 19 4997 9500 0 Blue 0
10 AM Wed 30 31 SE 6 8 4997 9500 0 Blue 0
11 AM Wed 33 35 SE 6 8 4997 9500 0 Blue 0
12 Noon Wed 35 37 SE 6 8 5604 9500 0 Blue 0
1 PM Wed 36 37 ENE 6 9 5604 9500 0 Blue 0
2 PM Wed 35 36 ENE 6 9 4997 9500 0 Blue 0
3 PM Wed 33 33 ENE 6 9 4997 9500 0 Blue 0
4 PM Wed 31 31 ENE 5 6 4997 9500 0 Blue 0
5 PM Wed 28 28 ENE 5 6 4997 9500 0 Blue 0
6 PM Wed 25 25 ENE 5 6 4997 9500 0 Blue 0
7 PM Wed 23 23 S 6 10 4997 9500 0 Blue 0
8 PM Wed 22 22 S 6 10 4997 9500 0 Blue 0
9 PM Wed 22 22 S 6 10 4997 9500 0 Blue 0
10 PM Wed 23 23 S 9 11 4997 9500 0 Blue 0
11 PM Wed 23 23 S 9 11 4997 9500 0 Blue 0
12 Midnight Thu 24 24 S 9 11 4997 9500 0 Blue 0
1 AM Thu 24 24 SSW 9 11 4997 9500 0 Blue 0
2 AM Thu 24 24 SSW 9 11 4997 9500 0 Blue 0
3 AM Thu 24 24 SSW 9 11 4997 9500 0 Blue 0
4 AM Thu 24 24 SSW 8 11 4997 9500 0 Blue 0
5 AM Thu 24 24 SSW 8 11 4997 9500 0 Blue 0
6 AM Thu 24 24 SSW 8 11 4997 9500 0 Blue 0
7 AM Thu 25 25 SSW 9 10 4997 9500 0 Blue 0
8 AM Thu 28 28 SSW 9 10 4997 9500 0 Blue 0
9 AM Thu 31 31 SSW 9 10 4997 9500 0 Blue 0
10 AM Thu 35 35 SSW 8 10 4997 9500 0 Blue 0
11 AM Thu 37 38 SSW 8 10 6194 9500 0 Blue 0
12 Noon Thu 39 40 SSW 8 10 7320 9500 0 Blue 0
1 PM Thu 40 40 WSW 8 10 7320 9500 0 Blue 0
2 PM Thu 39 39 WSW 8 10 6766 9500 0 Blue 0
3 PM Thu 37 37 WSW 8 10 5604 9500 0 Blue 0
4 PM Thu 34 34 S 6 9 4997 9500 0 Blue 0
5 PM Thu 32 32 S 6 9 4997 9500 0 Blue 0
6 PM Thu 29 29 S 6 9 4997 9500 0 Blue 0
7 PM Thu 27 27 S 6 9 4997 9500 0 Blue 0
8 PM Thu 26 26 S 6 9 4997 9500 0 Blue 0
9 PM Thu 26 26 S 6 9 4997 9500 0 Blue 0
10 PM Thu 26 26 S 9 11 4997 9500 0 Blue 0
11 PM Thu 26 26 S 9 11 4997 9500 0 Blue 0
12 Midnight Fri 27 27 S 9 11 4997 9500 0 Blue 0
1 AM Fri 27 27 SSW 8 11 4997 9500 0 Blue 0
2 AM Fri 27 27 SSW 8 11 4997 9500 0 Blue 0
3 AM Fri 27 27 SSW 8 11 4997 9500 0 Blue 0
4 AM Fri 26 26 S 8 11 4997 9500 0 Blue 0
5 AM Fri 26 26 S 8 11 4997 9500 0 Blue 0
6 AM Fri 26 26 S 8 11 4997 9500 0 Blue 0
7 AM Fri 26 26 S 8 10 4997 9500 0 Blue 0
8 AM Fri 29 29 S 8 10 4997 9500 0 Blue 0
9 AM Fri 33 33 S 8 10 4997 9500 0 Blue 0
10 AM Fri 36 36 S 8 11 4997 9500 0 Blue 0
11 AM Fri 38 38 S 8 11 6194 9500 0 Blue 0
12 Noon Fri 40 41 S 8 11 7858 9500 0 Blue 0
1 PM Fri 40 40 S 8 11 7320 9500 0 Blue 0
2 PM Fri 39 39 S 8 11 6766 9500 0 Blue 0
3 PM Fri 37 37 S 8 11 5604 9500 0 Blue 0
4 PM Fri 35 35 ESE 6 10 4997 9500 0 Blue 0
5 PM Fri 32 32 ESE 6 10 4997 9500 0 Blue 0
6 PM Fri 30 30 ESE 6 10 4997 9500 0 Blue 0
7 PM Fri 28 28 S 6 10 4997 9500 0 Blue 0
8 PM Fri 27 27 S 6 10 4997 9500 0 Blue 0
9 PM Fri 26 26 S 6 10 4997 9500 0 Blue 0
10 PM Fri 26 26 S 9 12 4997 9500 0 Blue 0
11 PM Fri 26 26 S 9 12 4997 9500 0 Blue 0
12 Midnight Sat 27 27 S 9 12 4997 9500 0 Blue 0
1 AM Sat 27 27 S 9 12 4997 9500 0 Blue 0
2 AM Sat 27 27 S 9 12 4997 9500 0 Blue 0
3 AM Sat 27 27 S 9 12 4997 9500 0 Blue 0
4 AM Sat 27 27 SSW 9 12 4997 9500 0 Blue 0
5 AM Sat 26 26 SSW 9 12 4997 9500 0 Blue 0
6 AM Sat 26 26 SSW 9 12 4997 9500 0 Blue 0
7 AM Sat 27 27 S 9 11 4997 9500 0 Blue 0
8 AM Sat 30 30 S 9 11 4997 9500 0 Blue 0
9 AM Sat 33 33 S 9 11 4997 9500 0 Blue 0
10 AM Sat 36 36 SSE 8 12 4997 9500 0 Blue 0
11 AM Sat 39 40 SSE 8 12 7320 9500 0 Blue 0
12 Noon Sat 40 41 SSE 8 12 7858 9500 0 Blue 0
1 PM Sat 41 42 ENE 9 11 8382 9500 0 Blue 0
2 PM Sat 40 41 ENE 9 11 7858 9500 0 Blue 0
3 PM Sat 38 38 ENE 9 11 6194 9500 0 Blue 0
4 PM Sat 35 35 NE 8 11 4997 9500 0 Blue 0
5 PM Sat 32 32 NE 8 11 4997 9500 0 Blue 0
6 PM Sat 29 29 NE 8 11 4997 9500 0 Blue 0
7 PM Sat 27 27 SSE 8 11 4997 9500 0 Blue 0
8 PM Sat 26 26 SSE 8 11 4997 9500 0 Blue 0
9 PM Sat 26 26 SSE 8 11 4997 9500 0 Blue 0
10 PM Sat 26 26 S 9 12 4997 9500 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]