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

Station:

KOAK

Date/Time:

20 OCT 2019

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)
5 AM Sun 36 36 SE 3 3504 4590 0 Blue 0
6 AM Sun 36 36 SE 3 3504 4590 0 Blue 0
7 AM Sun 36 36 SE 3 3504 4590 0 Blue 0
8 AM Sun 37 37 SE 3 3504 4590 0 Blue 0
9 AM Sun 42 42 SE 3 3504 4590 0 Blue 0
10 AM Sun 45 45 SE 3 3504 4590 0 Blue 0
11 AM Sun 48 49 W 3 3504 4590 0 Blue 0
12 Noon Sun 52 53 W 3 4610 4590 0 Blue 1
1 PM Sun 55 57 W 3 5903 4948 358 Blue 5
2 PM Sun 57 58 W 6 6214 5243 653 Blue 6
3 PM Sun 59 60 W 6 6910 5885 1295 Blue 8
4 PM Sun 59 59 W 6 6521 5575 985 Blue 7
5 PM Sun 59 59 W 6 6521 5575 985 Blue 7
6 PM Sun 56 56 W 6 5591 4602 12 Blue 4
7 PM Sun 54 54 W 6 4954 4590 0 Blue 2
8 PM Sun 53 53 S 3 4610 4590 0 Blue 1
9 PM Sun 51 51 S 3 3504 4590 0 Blue 0
10 PM Sun 50 50 S 3 3504 4590 0 Blue 0
11 PM Sun 49 49 S 3 3504 4590 0 Blue 0
12 Midnight Mon 47 47 S 3 3504 4590 0 Blue 0
1 AM Mon 47 47 S 3 3504 4590 0 Blue 0
2 AM Mon 45 45 SE 3 3504 4590 0 Blue 0
3 AM Mon 44 44 SE 3 3504 4590 0 Blue 0
4 AM Mon 43 43 SE 3 3504 4590 0 Blue 0
5 AM Mon 42 42 SE 5 3504 4590 0 Blue 0
6 AM Mon 41 41 SE 5 3504 4590 0 Blue 0
7 AM Mon 40 40 SE 5 3504 4590 0 Blue 0
8 AM Mon 41 41 E 5 3504 4590 0 Blue 0
9 AM Mon 47 47 E 5 3504 4590 0 Blue 0
10 AM Mon 50 51 E 5 3504 4590 0 Blue 0
11 AM Mon 55 57 NE 5 5903 4948 358 Blue 5
12 Noon Mon 58 61 NE 5 7220 6192 1602 Blue 9
1 PM Mon 61 64 NE 5 7724 7203 2613 Blue 12
2 PM Mon 64 67 NE 6 8312 7705 3115 Blue 15
3 PM Mon 66 68 NE 6 8696 7871 3281 Blue 16
4 PM Mon 66 67 NE 6 8312 7705 3115 Blue 15
5 PM Mon 65 65 NE 5 7892 7370 2780 Blue 13
6 PM Mon 62 62 NE 5 7388 6497 1907 Blue 10
7 PM Mon 59 59 NE 5 6521 5575 985 Blue 7
8 PM Mon 56 56 NE 5 5591 4602 12 Blue 4
9 PM Mon 54 54 NE 5 4954 4590 0 Blue 2
10 PM Mon 53 53 NE 5 4610 4590 0 Blue 1
11 PM Mon 52 52 E 5 3865 4590 0 Blue 0
12 Midnight Tue 51 51 E 5 3504 4590 0 Blue 0
1 AM Tue 50 50 E 5 3504 4590 0 Blue 0
2 AM Tue 48 48 E 5 3504 4590 0 Blue 0
3 AM Tue 47 47 E 5 3504 4590 0 Blue 0
4 AM Tue 46 46 E 5 3504 4590 0 Blue 0
5 AM Tue 44 44 E 5 3504 4590 0 Blue 0
6 AM Tue 43 43 E 5 3504 4590 0 Blue 0
7 AM Tue 43 43 E 5 3504 4590 0 Blue 0
8 AM Tue 44 44 E 5 3504 4590 0 Blue 0
9 AM Tue 48 48 E 5 3504 4590 0 Blue 0
10 AM Tue 53 54 E 5 4954 4590 0 Blue 2
11 AM Tue 58 60 NE 6 6910 5885 1295 Blue 8
12 Noon Tue 62 65 NE 6 7892 7370 2780 Blue 13
1 PM Tue 64 67 NE 6 8312 7705 3115 Blue 15
2 PM Tue 66 69 NE 6 9075 8038 3448 Blue 17
3 PM Tue 67 69 NE 6 9075 8038 3448 Blue 17
4 PM Tue 68 69 NE 6 9075 8038 3448 Blue 17
5 PM Tue 67 67 N 8 8312 7705 3115 Blue 15
6 PM Tue 65 65 N 8 7892 7370 2780 Blue 13
7 PM Tue 61 61 N 8 7220 6192 1602 Blue 9
8 PM Tue 58 58 N 8 6214 5243 653 Blue 6
9 PM Tue 55 55 N 8 5256 4590 0 Blue 3
10 PM Tue 54 54 N 8 4954 4590 0 Blue 2
11 PM Tue 52 52 NE 5 3865 4590 0 Blue 0
12 Midnight Wed 51 51 NE 5 3504 4590 0 Blue 0
1 AM Wed 50 50 NE 5 3504 4590 0 Blue 0
2 AM Wed 48 48 NE 5 3504 4590 0 Blue 0
3 AM Wed 47 47 NE 5 3504 4590 0 Blue 0
4 AM Wed 45 45 NE 5 3504 4590 0 Blue 0
5 AM Wed 43 43 E 6 3504 4590 0 Blue 0
6 AM Wed 42 42 E 6 3504 4590 0 Blue 0
7 AM Wed 41 41 E 6 3504 4590 0 Blue 0
8 AM Wed 42 42 E 6 3504 4590 0 Blue 0
9 AM Wed 45 45 E 6 3504 4590 0 Blue 0
10 AM Wed 49 50 E 6 3504 4590 0 Blue 0
11 AM Wed 54 56 NE 9 5591 4602 12 Blue 4
12 Noon Wed 59 62 NE 9 7388 6497 1907 Blue 10
1 PM Wed 63 66 NE 9 8060 7537 2947 Blue 14
2 PM Wed 66 69 NE 9 9075 8038 3448 Blue 17
3 PM Wed 67 69 NE 9 9075 8038 3448 Blue 17
4 PM Wed 67 68 NE 9 8696 7871 3281 Blue 16
5 PM Wed 66 66 NE 12 8060 7537 2947 Blue 14
6 PM Wed 63 63 NE 12 7556 6862 2272 Blue 11
7 PM Wed 60 60 NE 12 6910 5885 1295 Blue 8
8 PM Wed 57 57 NE 12 5903 4948 358 Blue 5
9 PM Wed 55 55 NE 12 5256 4590 0 Blue 3
10 PM Wed 54 54 NE 12 4954 4590 0 Blue 2
11 PM Wed 52 52 NE 8 3865 4590 0 Blue 0
12 Midnight Thu 51 51 NE 8 3504 4590 0 Blue 0
1 AM Thu 49 49 NE 8 3504 4590 0 Blue 0
2 AM Thu 47 47 NE 8 3504 4590 0 Blue 0
3 AM Thu 45 45 NE 8 3504 4590 0 Blue 0
4 AM Thu 44 44 NE 8 3504 4590 0 Blue 0
5 AM Thu 42 42 E 8 3504 4590 0 Blue 0
6 AM Thu 41 41 E 8 3504 4590 0 Blue 0
7 AM Thu 41 41 E 8 3504 4590 0 Blue 0
8 AM Thu 42 42 E 8 3504 4590 0 Blue 0
9 AM Thu 46 46 E 8 3504 4590 0 Blue 0
10 AM Thu 50 51 E 8 3504 4590 0 Blue 0
11 AM Thu 55 57 E 9 5903 4948 358 Blue 5
12 Noon Thu 59 62 E 9 7388 6497 1907 Blue 10
1 PM Thu 63 66 E 9 8060 7537 2947 Blue 14
2 PM Thu 66 69 E 9 9075 8038 3448 Blue 17
3 PM Thu 67 69 E 9 9075 8038 3448 Blue 17
4 PM Thu 67 68 E 9 8696 7871 3281 Blue 16
5 PM Thu 66 66 E 9 8060 7537 2947 Blue 14
6 PM Thu 63 63 E 9 7556 6862 2272 Blue 11
7 PM Thu 59 59 E 9 6521 5575 985 Blue 7
8 PM Thu 56 56 E 9 5591 4602 12 Blue 4
9 PM Thu 54 54 E 9 4954 4590 0 Blue 2
10 PM Thu 52 52 E 9 3865 4590 0 Blue 0
11 PM Thu 51 51 E 6 3504 4590 0 Blue 0
12 Midnight Fri 50 50 E 6 3504 4590 0 Blue 0
1 AM Fri 49 49 E 6 3504 4590 0 Blue 0
2 AM Fri 47 47 E 6 3504 4590 0 Blue 0
3 AM Fri 45 45 E 6 3504 4590 0 Blue 0
4 AM Fri 44 44 E 6 3504 4590 0 Blue 0
5 AM Fri 43 43 SE 5 3504 4590 0 Blue 0
6 AM Fri 41 41 SE 5 3504 4590 0 Blue 0
7 AM Fri 41 41 SE 5 3504 4590 0 Blue 0
8 AM Fri 43 43 SE 5 3504 4590 0 Blue 0
9 AM Fri 47 47 SE 5 3504 4590 0 Blue 0
10 AM Fri 52 53 SE 5 4610 4590 0 Blue 1
11 AM Fri 58 60 S 2 6910 5885 1295 Blue 8
12 Noon Fri 62 65 S 2 7892 7370 2780 Blue 13
1 PM Fri 65 68 S 2 8696 7871 3281 Blue 16
2 PM Fri 68 71 S 2 9818 8639 4049 Blue 19
3 PM Fri 69 71 S 2 9818 8639 4049 Blue 19
4 PM Fri 70 71 S 2 9818 8639 4049 Blue 19
5 PM Fri 69 69 W 6 9075 8038 3448 Blue 17
6 PM Fri 66 66 W 6 8060 7537 2947 Blue 14
7 PM Fri 62 62 W 6 7388 6497 1907 Blue 10
8 PM Fri 58 58 W 6 6214 5243 653 Blue 6
9 PM Fri 55 55 W 6 5256 4590 0 Blue 3
10 PM Fri 53 53 W 6 4610 4590 0 Blue 1
11 PM Fri 52 52 S 5 3865 4590 0 Blue 0
12 Midnight Sat 50 50 S 5 3504 4590 0 Blue 0
1 AM Sat 49 49 S 5 3504 4590 0 Blue 0
2 AM Sat 47 47 S 5 3504 4590 0 Blue 0
3 AM Sat 46 46 S 5 3504 4590 0 Blue 0
4 AM Sat 44 44 S 5 3504 4590 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 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 [email protected]