Detailed Predictions for: Slide Mountain
Launch Lat, Long, Altitude (f): 39.31966654775122, -119.8678295108672, 8200
LZ Altitude (f): 6000
Sounding

Station:

KREV

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 45 30 WSW 8 11 8884 8884 684 Blue 0
1 AM Tue 42 27 SSW 8 11 8884 8884 684 Blue 0
2 AM Tue 42 27 S 8 12 8884 8884 684 Blue 0
3 AM Tue 43 28 SSW 8 12 8884 8884 684 Blue 0
4 AM Tue 43 28 SSW 6 10 8884 8884 684 Blue 0
5 AM Tue 43 28 SSW 10 14 8884 8884 684 Blue 0
6 AM Tue 46 31 SSW 10 14 8884 8884 684 Blue 0
7 AM Tue 44 29 SSW 10 14 8884 8884 684 Blue 0
8 AM Tue 49 34 SSW 16 24 8884 8884 684 Blue 0
9 AM Tue 50 36 SSW 16 24 8884 8884 684 Blue 0
10 AM Tue 51 38 SSW 16 24 8884 8884 684 Blue 0
11 AM Tue 54 43 SSW 16 24 8884 8884 684 Blue 0
12 Noon Tue 57 47 SSW 16 24 8944 8884 684 Blue 0
1 PM Tue 59 49 SSW 16 24 9586 8884 684 Blue 0
2 PM Tue 61 51 SW 16 24 9754 9332 1132 Blue 2
3 PM Tue 62 51 SW 16 24 9754 9332 1132 Blue 2
4 PM Tue 62 49 SW 16 24 9586 8884 684 Blue 0
5 PM Tue 60 46 WSW 12 19 8884 8884 684 Blue 0
6 PM Tue 57 42 WSW 12 19 8884 8884 684 Blue 0
7 PM Tue 55 40 WSW 12 19 8884 8884 684 Blue 0
8 PM Tue 54 39 WSW 12 19 8884 8884 684 Blue 0
9 PM Tue 54 39 WSW 12 19 8884 8884 684 Blue 0
10 PM Tue 53 38 WSW 12 19 8884 8884 684 Blue 0
11 PM Tue 53 38 WSW 14 23 8884 8884 684 Blue 0
12 Midnight Wed 52 37 WSW 14 23 8884 8884 684 Blue 0
1 AM Wed 52 37 WSW 14 23 8884 8884 684 Blue 0
2 AM Wed 52 37 WSW 16 24 8884 8884 684 Blue 0
3 AM Wed 50 35 WSW 16 24 8884 8884 684 Blue 0
4 AM Wed 52 37 WSW 16 24 8884 8884 684 Blue 0
5 AM Wed 50 35 WSW 20 31 8884 8884 684 Blue 0
6 AM Wed 49 34 WSW 20 31 8884 8884 684 Blue 0
7 AM Wed 49 34 WSW 20 31 8884 8884 684 Blue 0
8 AM Wed 55 40 SW 24 36 8884 8884 684 Blue 0
9 AM Wed 55 41 SW 24 36 8884 8884 684 Blue 0
10 AM Wed 58 45 SW 24 36 8884 8884 684 Blue 0
11 AM Wed 59 47 SW 23 34 8944 8884 684 Blue 0
12 Noon Wed 60 49 SW 23 34 9586 8884 684 Blue 0
1 PM Wed 60 49 SW 23 34 9586 8884 684 Blue 0
2 PM Wed 61 49 WSW 27 41 9586 8884 684 Blue 0
3 PM Wed 61 49 WSW 27 41 9586 8884 684 Blue 0
4 PM Wed 60 47 WSW 27 41 8944 8884 684 Blue 0
5 PM Wed 58 44 WSW 26 40 8884 8884 684 Blue 0
6 PM Wed 56 41 WSW 26 40 8884 8884 684 Blue 0
7 PM Wed 53 38 WSW 26 40 8884 8884 684 Blue 0
8 PM Wed 51 36 W 19 29 8884 8884 684 Blue 0
9 PM Wed 50 35 W 19 29 8884 8884 684 Blue 0
10 PM Wed 50 35 W 19 29 8884 8884 684 Blue 0
11 PM Wed 50 35 WNW 14 23 8884 8884 684 Blue 0
12 Midnight Thu 49 34 WNW 14 23 8884 8884 684 Blue 0
1 AM Thu 48 33 WNW 14 23 8884 8884 684 Blue 0
2 AM Thu 47 32 WNW 13 20 8884 8884 684 Blue 0
3 AM Thu 46 31 WNW 13 20 8884 8884 684 Blue 0
4 AM Thu 46 31 WNW 13 20 8884 8884 684 Blue 0
5 AM Thu 45 30 NW 8 11 8884 8884 684 Blue 0
6 AM Thu 46 31 NW 8 11 8884 8884 684 Blue 0
7 AM Thu 47 32 NW 8 11 8884 8884 684 Blue 0
8 AM Thu 48 33 NNE 6 11 8884 8884 684 Blue 0
9 AM Thu 48 34 NNE 6 11 8884 8884 684 Blue 0
10 AM Thu 49 36 NNE 6 11 8884 8884 684 Blue 0
11 AM Thu 49 38 ENE 9 13 8884 8884 684 Blue 0
12 Noon Thu 50 39 ENE 9 13 8884 8884 684 Blue 0
1 PM Thu 52 42 ENE 9 13 8884 8884 684 Blue 0
2 PM Thu 53 42 ENE 10 16 8884 8884 684 Blue 0
3 PM Thu 54 42 ENE 10 16 8884 8884 684 Blue 0
4 PM Thu 54 41 ENE 10 16 8884 8884 684 Blue 0
5 PM Thu 54 40 ENE 10 14 8884 8884 684 Blue 0
6 PM Thu 53 38 ENE 10 14 8884 8884 684 Blue 0
7 PM Thu 52 37 ENE 10 14 8884 8884 684 Blue 0
8 PM Thu 51 36 ENE 11 17 8884 8884 684 Blue 0
9 PM Thu 50 35 ENE 11 17 8884 8884 684 Blue 0
10 PM Thu 49 34 ENE 11 17 8884 8884 684 Blue 0
11 PM Thu 49 34 ENE 12 18 8884 8884 684 Blue 0
12 Midnight Fri 49 34 ENE 12 18 8884 8884 684 Blue 0
1 AM Fri 48 33 ENE 12 18 8884 8884 684 Blue 0
2 AM Fri 48 33 ESE 10 14 8884 8884 684 Blue 0
3 AM Fri 48 33 ESE 10 14 8884 8884 684 Blue 0
4 AM Fri 47 32 ESE 10 14 8884 8884 684 Blue 0
5 AM Fri 47 32 S 9 13 8884 8884 684 Blue 0
6 AM Fri 48 33 S 9 13 8884 8884 684 Blue 0
7 AM Fri 49 34 S 9 13 8884 8884 684 Blue 0
8 AM Fri 50 35 S 6 11 8884 8884 684 Blue 0
9 AM Fri 51 37 S 6 11 8884 8884 684 Blue 0
10 AM Fri 52 39 S 6 11 8884 8884 684 Blue 0
11 AM Fri 54 43 SE 6 11 8884 8884 684 Blue 0
12 Noon Fri 56 46 SE 6 11 8884 8884 684 Blue 0
1 PM Fri 59 49 SE 6 11 9586 8884 684 Blue 0
2 PM Fri 61 50 SE 9 13 9670 8950 750 Blue 1
3 PM Fri 62 50 SE 9 13 9670 8950 750 Blue 1
4 PM Fri 62 49 SE 9 13 9586 8884 684 Blue 0
5 PM Fri 61 47 WNW 10 14 8944 8884 684 Blue 0
6 PM Fri 58 43 WNW 10 14 8884 8884 684 Blue 0
7 PM Fri 56 41 WNW 10 14 8884 8884 684 Blue 0
8 PM Fri 54 39 WNW 12 19 8884 8884 684 Blue 0
9 PM Fri 53 38 WNW 12 19 8884 8884 684 Blue 0
10 PM Fri 53 38 WNW 12 19 8884 8884 684 Blue 0
11 PM Fri 53 38 W 10 16 8884 8884 684 Blue 0
12 Midnight Sat 52 37 W 10 16 8884 8884 684 Blue 0
1 AM Sat 51 36 W 10 16 8884 8884 684 Blue 0
2 AM Sat 50 35 W 9 13 8884 8884 684 Blue 0
3 AM Sat 50 35 W 9 13 8884 8884 684 Blue 0
4 AM Sat 49 34 W 9 13 8884 8884 684 Blue 0
5 AM Sat 49 34 W 9 14 8884 8884 684 Blue 0
6 AM Sat 50 35 W 9 14 8884 8884 684 Blue 0
7 AM Sat 51 36 W 9 14 8884 8884 684 Blue 0
8 AM Sat 52 37 W 9 12 8884 8884 684 Blue 0
9 AM Sat 53 39 W 9 12 8884 8884 684 Blue 0
10 AM Sat 55 42 W 9 12 8884 8884 684 Blue 0
11 AM Sat 56 45 W 9 13 8884 8884 684 Blue 0
12 Noon Sat 58 48 W 9 13 9331 8884 684 Blue 0
1 PM Sat 59 49 W 9 13 9586 8884 684 Blue 0
2 PM Sat 60 50 WSW 10 16 9670 8950 750 Blue 1
3 PM Sat 60 49 WSW 10 16 9586 8884 684 Blue 0
4 PM Sat 59 46 WSW 10 16 8884 8884 684 Blue 0
5 PM Sat 58 44 W 16 23 8884 8884 684 Blue 0
6 PM Sat 57 42 W 16 23 8884 8884 684 Blue 0
7 PM Sat 55 40 W 16 23 8884 8884 684 Blue 0
8 PM Sat 54 39 W 16 24 8884 8884 684 Blue 0
9 PM Sat 53 38 W 16 24 8884 8884 684 Blue 0
10 PM Sat 53 38 W 16 24 8884 8884 684 Blue 0
11 PM Sat 52 37 W 10 16 8884 8884 684 Blue 0
12 Midnight Sun 51 36 W 10 16 8884 8884 684 Blue 0
1 AM Sun 51 36 W 10 16 8884 8884 684 Blue 0
2 AM Sun 50 35 W 10 14 8884 8884 684 Blue 0
3 AM Sun 49 34 W 10 14 8884 8884 684 Blue 0
4 AM Sun 49 34 W 10 14 8884 8884 684 Blue 0
5 AM Sun 49 34 W 13 20 8884 8884 684 Blue 0
6 AM Sun 50 35 W 13 20 8884 8884 684 Blue 0
7 AM Sun 51 36 W 13 20 8884 8884 684 Blue 0
8 AM Sun 52 37 WSW 13 19 8884 8884 684 Blue 0
9 AM Sun 53 39 WSW 13 19 8884 8884 684 Blue 0
10 AM Sun 53 40 WSW 13 19 8884 8884 684 Blue 0
11 AM Sun 54 43 SW 13 21 8884 8884 684 Blue 0
12 Noon Sun 55 44 SW 13 21 8884 8884 684 Blue 0
1 PM Sun 56 46 SW 13 21 8884 8884 684 Blue 0
2 PM Sun 57 45 WSW 14 21 8884 8884 684 Blue 0
3 PM Sun 57 45 WSW 14 21 8884 8884 684 Blue 0
4 PM Sun 57 44 WSW 14 21 8884 8884 684 Blue 0
5 PM Sun 56 42 W 14 21 8884 8884 684 Blue 0
6 PM Sun 55 40 W 14 21 8884 8884 684 Blue 0
7 PM Sun 53 38 W 14 21 8884 8884 684 Blue 0
8 PM Sun 52 37 W 14 21 8884 8884 684 Blue 0
9 PM Sun 51 36 W 14 21 8884 8884 684 Blue 0
10 PM Sun 51 36 W 14 21 8884 8884 684 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]