Detailed Predictions for: Hat Creek Rim
Launch Altitude (f): 4590
LZ Altitude (f): 3575
Sounding

Station:

KOAK

Date/Time:

17 NOV 2017

Temp/Wind data from:

NOAA Digital Forecast

Site Forecasts
Time
(Local)
High
Temp

Puddle
Temp

Wind
(mph)
Thermal
Ceiling

(ft)
Soaring
Ceiling

(ft)
Above
Launch

(ft)
Thermal
Type
Thermal
Index

(F)
4 AM Fri 36 36 W 7 3950 4590 0 Blue 0
5 AM Fri 35 35 W 7 3950 4590 0 Blue 0
6 AM Fri 34 34 W 7 3950 4590 0 Blue 0
7 AM Fri 33 33 W 2 3950 4590 0 Blue 0
8 AM Fri 34 34 W 2 3950 4590 0 Blue 0
9 AM Fri 36 36 W 2 3950 4590 0 Blue 0
10 AM Fri 38 39 E 2 4138 4590 0 Blue 0
11 AM Fri 40 41 E 2 4926 4590 0 Blue 2
12 Noon Fri 42 44 E 2 6520 4893 303 Blue 5
1 PM Fri 44 45 NE 3 6650 5903 1313 Blue 6
2 PM Fri 44 45 NE 3 6650 5903 1313 Blue 6
3 PM Fri 43 43 NE 3 6298 4659 69 Blue 4
4 PM Fri 41 41 NE 6 4926 4590 0 Blue 2
5 PM Fri 38 38 NE 6 3950 4590 0 Blue 0
6 PM Fri 36 36 NE 6 3950 4590 0 Blue 0
7 PM Fri 33 33 SE 5 3950 4590 0 Blue 0
8 PM Fri 32 32 SE 5 3950 4590 0 Blue 0
9 PM Fri 31 31 SE 5 3950 4590 0 Blue 0
10 PM Fri 31 31 SE 5 3950 4590 0 Blue 0
11 PM Fri 30 30 SE 5 3950 4590 0 Blue 0
12 Midnight Sat 29 29 SE 5 3950 4590 0 Blue 0
1 AM Sat 28 28 SE 7 3950 4590 0 Blue 0
2 AM Sat 28 28 SE 7 3950 4590 0 Blue 0
3 AM Sat 28 28 SE 7 3950 4590 0 Blue 0
4 AM Sat 28 28 SE 7 3950 4590 0 Blue 0
5 AM Sat 27 27 SE 7 3950 4590 0 Blue 0
6 AM Sat 27 27 SE 7 3950 4590 0 Blue 0
7 AM Sat 28 28 SE 7 3950 4590 0 Blue 0
8 AM Sat 31 31 SE 7 3950 4590 0 Blue 0
9 AM Sat 35 35 SE 7 3950 4590 0 Blue 0
10 AM Sat 40 41 SE 2 4926 4590 0 Blue 2
11 AM Sat 45 47 SE 2 6868 6502 1912 Blue 8
12 Noon Sat 49 51 SE 2 7337 7029 2439 Blue 12
1 PM Sat 51 53 S 5 7512 7240 2650 Blue 14
2 PM Sat 52 53 S 5 7512 7240 2650 Blue 14
3 PM Sat 51 51 S 5 7337 7029 2439 Blue 12
4 PM Sat 49 49 S 3 7161 6742 2152 Blue 10
5 PM Sat 45 45 S 3 6650 5903 1313 Blue 6
6 PM Sat 41 41 S 3 4926 4590 0 Blue 2
7 PM Sat 38 38 S 3 3950 4590 0 Blue 0
8 PM Sat 37 37 S 3 3950 4590 0 Blue 0
9 PM Sat 36 36 S 3 3950 4590 0 Blue 0
10 PM Sat 36 36 SE 5 3950 4590 0 Blue 0
11 PM Sat 35 35 SE 5 3950 4590 0 Blue 0
12 Midnight Sun 34 34 SE 5 3950 4590 0 Blue 0
1 AM Sun 33 33 SE 5 3950 4590 0 Blue 0
2 AM Sun 33 33 SE 5 3950 4590 0 Blue 0
3 AM Sun 33 33 SE 5 3950 4590 0 Blue 0
4 AM Sun 32 32 SE 5 3950 4590 0 Blue 0
5 AM Sun 31 31 SE 5 3950 4590 0 Blue 0
6 AM Sun 31 31 SE 5 3950 4590 0 Blue 0
7 AM Sun 32 32 SE 5 3950 4590 0 Blue 0
8 AM Sun 35 35 SE 5 3950 4590 0 Blue 0
9 AM Sun 40 40 SE 5 4664 4590 0 Blue 1
10 AM Sun 44 44 SW 7 6520 4893 303 Blue 5
11 AM Sun 48 49 SW 7 7161 6742 2152 Blue 10
12 Noon Sun 50 51 SW 7 7337 7029 2439 Blue 12
1 PM Sun 51 52 SW 7 7425 7152 2562 Blue 13
2 PM Sun 51 51 SW 7 7337 7029 2439 Blue 12
3 PM Sun 50 50 SW 7 7249 6851 2261 Blue 11
4 PM Sun 48 48 SW 5 7047 6641 2051 Blue 9
5 PM Sun 44 44 SW 5 6520 4893 303 Blue 5
6 PM Sun 41 41 SW 5 4926 4590 0 Blue 2
7 PM Sun 38 38 SW 5 3950 4590 0 Blue 0
8 PM Sun 37 37 SW 5 3950 4590 0 Blue 0
9 PM Sun 37 37 SW 5 3950 4590 0 Blue 0
10 PM Sun 38 38 SW 7 3950 4590 0 Blue 0
11 PM Sun 38 38 SW 7 3950 4590 0 Blue 0
12 Midnight Mon 38 38 SW 7 3950 4590 0 Blue 0
1 AM Mon 38 38 SW 7 3950 4590 0 Blue 0
2 AM Mon 38 38 SW 7 3950 4590 0 Blue 0
3 AM Mon 38 38 SW 7 3950 4590 0 Blue 0
4 AM Mon 38 38 S 7 3950 4590 0 Blue 0
5 AM Mon 38 38 S 7 3950 4590 0 Blue 0
6 AM Mon 38 38 S 7 3950 4590 0 Blue 0
7 AM Mon 39 39 S 7 4138 4590 0 Blue 0
8 AM Mon 41 41 S 7 4926 4590 0 Blue 2
9 AM Mon 43 43 S 7 6298 4659 69 Blue 4
10 AM Mon 45 45 SW 8 6650 5903 1313 Blue 6
11 AM Mon 48 48 SW 8 7047 6641 2051 Blue 9
12 Noon Mon 49 49 SW 8 7161 6742 2152 Blue 10
1 PM Mon 50 50 SW 8 7249 6851 2261 Blue 11
2 PM Mon 49 49 SW 8 7161 6742 2152 Blue 10
3 PM Mon 48 48 SW 8 7047 6641 2051 Blue 9
4 PM Mon 45 45 SW 6 6650 5903 1313 Blue 6
5 PM Mon 43 43 SW 6 6298 4659 69 Blue 4
6 PM Mon 42 42 SW 6 5930 4590 0 Blue 3
7 PM Mon 41 41 SW 6 4926 4590 0 Blue 2
8 PM Mon 40 40 SW 6 4664 4590 0 Blue 1
9 PM Mon 40 40 SW 6 4664 4590 0 Blue 1
10 PM Mon 40 40 S 6 4664 4590 0 Blue 1
11 PM Mon 41 41 S 6 4926 4590 0 Blue 2
12 Midnight Tue 42 42 S 6 5930 4590 0 Blue 3
1 AM Tue 42 42 S 6 5930 4590 0 Blue 3
2 AM Tue 43 43 S 6 6298 4659 69 Blue 4
3 AM Tue 42 42 S 6 5930 4590 0 Blue 3
4 AM Tue 42 42 S 8 5930 4590 0 Blue 3
5 AM Tue 43 43 S 8 6298 4659 69 Blue 4
6 AM Tue 44 44 S 8 6520 4893 303 Blue 5
7 AM Tue 45 45 S 8 6650 5903 1313 Blue 6
8 AM Tue 46 46 S 8 6751 6282 1692 Blue 7
9 AM Tue 47 47 S 8 6868 6502 1912 Blue 8
10 AM Tue 49 49 S 7 7161 6742 2152 Blue 10
11 AM Tue 51 51 S 7 7337 7029 2439 Blue 12
12 Noon Tue 53 53 S 7 7512 7240 2650 Blue 14
1 PM Tue 55 55 S 7 7689 7415 2825 Blue 16
2 PM Tue 55 55 S 7 7689 7415 2825 Blue 16
3 PM Tue 54 54 S 7 7600 7327 2737 Blue 15
4 PM Tue 53 53 S 12 7512 7240 2650 Blue 14
5 PM Tue 52 52 S 12 7425 7152 2562 Blue 13
6 PM Tue 50 50 S 12 7249 6851 2261 Blue 11
7 PM Tue 49 49 S 12 7161 6742 2152 Blue 10
8 PM Tue 49 49 S 12 7161 6742 2152 Blue 10
9 PM Tue 48 48 S 12 7047 6641 2051 Blue 9
10 PM Tue 48 48 S 12 7047 6641 2051 Blue 9
11 PM Tue 48 48 S 12 7047 6641 2051 Blue 9
12 Midnight Wed 48 48 S 12 7047 6641 2051 Blue 9
1 AM Wed 48 48 S 12 7047 6641 2051 Blue 9
2 AM Wed 47 47 S 12 6868 6502 1912 Blue 8
3 AM Wed 46 46 S 12 6751 6282 1692 Blue 7
4 AM Wed 46 46 S 10 6751 6282 1692 Blue 7
5 AM Wed 45 45 S 10 6650 5903 1313 Blue 6
6 AM Wed 45 45 S 10 6650 5903 1313 Blue 6
7 AM Wed 46 46 S 10 6751 6282 1692 Blue 7
8 AM Wed 47 47 S 10 6868 6502 1912 Blue 8
9 AM Wed 50 50 S 10 7249 6851 2261 Blue 11
10 AM Wed 52 52 S 14 7425 7152 2562 Blue 13
11 AM Wed 54 54 S 14 7600 7327 2737 Blue 15
12 Noon Wed 56 56 S 14 7780 7502 2912 Blue 17
1 PM Wed 57 57 S 14 8037 7590 3000 Blue 18
2 PM Wed 57 57 S 14 8037 7590 3000 Blue 18
3 PM Wed 56 56 S 14 7780 7502 2912 Blue 17
4 PM Wed 55 55 S 14 7689 7415 2825 Blue 16
5 PM Wed 53 53 S 14 7512 7240 2650 Blue 14
6 PM Wed 51 51 S 14 7337 7029 2439 Blue 12
7 PM Wed 49 49 S 14 7161 6742 2152 Blue 10
8 PM Wed 48 48 S 14 7047 6641 2051 Blue 9
9 PM Wed 47 47 S 14 6868 6502 1912 Blue 8
10 PM Wed 47 47 S 10 6868 6502 1912 Blue 8
11 PM Wed 47 47 S 10 6868 6502 1912 Blue 8
12 Midnight Thu 46 46 S 10 6751 6282 1692 Blue 7
1 AM Thu 45 45 S 10 6650 5903 1313 Blue 6
2 AM Thu 45 45 S 10 6650 5903 1313 Blue 6
3 AM Thu 44 44 S 10 6520 4893 303 Blue 5

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 website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the National Weather Service 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 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 ac_soaring@yahoo.com