Detailed Predictions for: Weaver Bally
Launch Lat, Long, Altitude (f): 40.796231, -123.00509, 6900
LZ Altitude (f): 1480
Sounding

Station:

KMFR

Date/Time:

24 JUL 2024

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 Wed 67 67 NW 3 6 6255 6900 0 Blue 0
1 AM Wed 66 66 WNW 2 5 5699 6900 0 Blue 0
2 AM Wed 64 64 WNW 2 4 5699 6900 0 Blue 0
3 AM Wed 63 63 NW 2 4 5699 6900 0 Blue 0
4 AM Wed 63 63 NW 1 3 5699 6900 0 Blue 0
5 AM Wed 62 62 NNW 1 3 5699 6900 0 Blue 0
6 AM Wed 63 63 NNW 2 3 5699 6900 0 Blue 0
7 AM Wed 71 71 NNW 0 1 9274 6911 11 Blue 2
8 AM Wed 78 79 E 1 2 13838 11852 4952 Blue 10
9 AM Wed 84 86 ESE 3 3 16804 15169 8269 White 16
10 AM Wed 89 93 ESE 3 4 18248 18248 11348 White 23
11 AM Wed 94 95 SE 3 4 18656 18656 11756 White 25
12 Noon Wed 96 97 SE 3 3 19058 19058 12158 White 27
1 PM Wed 98 106 S 6 7 20876 20876 13976 White 36
2 PM Wed 99 107 SW 8 9 21071 21071 14171 White 37
3 PM Wed 99 106 WSW 9 11 20876 20876 13976 White 36
4 PM Wed 99 104 WSW 11 12 20484 20484 13584 White 34
5 PM Wed 97 100 WSW 13 14 19692 19692 12792 White 30
6 PM Wed 94 96 WSW 12 14 18857 18857 11957 White 26
7 PM Wed 89 89 WSW 9 11 17425 17425 10525 White 19
8 PM Wed 80 80 W 6 11 14148 12175 5275 Blue 11
9 PM Wed 74 74 W 6 12 11006 9251 2351 Blue 5
10 PM Wed 69 69 W 5 10 7542 6900 0 Blue 0
11 PM Wed 65 65 W 4 9 5699 6900 0 Blue 0
12 Midnight Thu 62 62 W 4 10 5699 6900 0 Blue 0
1 AM Thu 60 60 WNW 4 9 5699 6900 0 Blue 0
2 AM Thu 58 58 WNW 4 8 5699 6900 0 Blue 0
3 AM Thu 57 57 WNW 3 7 5699 6900 0 Blue 0
4 AM Thu 56 56 WNW 3 7 5699 6900 0 Blue 0
5 AM Thu 55 55 WNW 2 6 5699 6900 0 Blue 0
6 AM Thu 56 56 WNW 2 5 5699 6900 0 Blue 0
7 AM Thu 64 64 WNW 2 4 5699 6900 0 Blue 0
8 AM Thu 72 73 W 0 1 10151 8370 1470 Blue 4
9 AM Thu 78 80 SE 0 1 14148 12175 5275 Blue 11
10 AM Thu 84 88 SE 2 2 17218 16286 9386 White 18
11 AM Thu 89 95 SSE 2 2 18656 18656 11756 White 25
12 Noon Thu 93 100 S 2 2 19692 19692 12792 White 30
1 PM Thu 95 103 SSW 2 3 20288 20288 13388 White 33
2 PM Thu 97 105 SW 5 6 20679 20679 13779 White 35
3 PM Thu 97 104 SW 9 10 20484 20484 13584 White 34
4 PM Thu 97 102 SW 11 12 20089 20089 13189 White 32
5 PM Thu 95 98 WSW 11 13 19274 19274 12374 White 28
6 PM Thu 93 95 WSW 11 12 18656 18656 11756 White 25
7 PM Thu 87 87 WSW 8 9 17012 15514 8614 White 17
8 PM Thu 76 76 W 6 10 11903 10085 3185 Blue 7
9 PM Thu 69 69 W 6 12 7542 6900 0 Blue 0
10 PM Thu 63 63 WNW 6 12 5699 6900 0 Blue 0
11 PM Thu 59 59 WNW 5 12 5699 6900 0 Blue 0
12 Midnight Fri 56 56 WNW 5 10 5699 6900 0 Blue 0
1 AM Fri 54 54 WNW 4 8 5699 6900 0 Blue 0
2 AM Fri 52 52 WNW 4 8 5699 6900 0 Blue 0
3 AM Fri 51 51 WNW 3 7 5699 6900 0 Blue 0
4 AM Fri 50 50 WNW 2 5 5699 6900 0 Blue 0
5 AM Fri 49 49 NW 2 4 5699 6900 0 Blue 0
6 AM Fri 51 51 NW 2 4 5699 6900 0 Blue 0
7 AM Fri 60 60 NW 1 3 5699 6900 0 Blue 0
8 AM Fri 68 69 E 0 0 7542 6900 0 Blue 0
9 AM Fri 75 77 ESE 2 2 12229 10894 3994 Blue 8
10 AM Fri 81 85 ESE 2 3 16597 14426 7526 White 15
11 AM Fri 86 92 SE 3 3 18042 18042 11142 White 22
12 Noon Fri 89 96 SE 3 3 18857 18857 11957 White 26
1 PM Fri 92 100 SE 3 4 19692 19692 12792 White 30
2 PM Fri 94 102 ESE 4 4 20089 20089 13189 White 32
3 PM Fri 95 102 SE 6 7 20089 20089 13189 White 32
4 PM Fri 94 99 SSE 6 7 19492 19492 12592 White 29
5 PM Fri 93 96 SSW 6 7 18857 18857 11957 White 26
6 PM Fri 91 93 SW 6 7 18248 18248 11348 White 23
7 PM Fri 85 85 WSW 4 5 16597 14426 7526 White 15
8 PM Fri 75 75 WSW 4 9 11521 9558 2658 Blue 6
9 PM Fri 67 67 WNW 4 10 6255 6900 0 Blue 0
10 PM Fri 62 62 WNW 4 10 5699 6900 0 Blue 0
11 PM Fri 58 58 WNW 4 9 5699 6900 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]