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

Station:

KOAK

Date/Time:

15 JUL 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 Mon 59 59 SE 5 2835 4590 0 Blue 0
6 AM Mon 62 62 SE 5 2835 4590 0 Blue 0
7 AM Mon 58 58 SE 5 2835 4590 0 Blue 0
8 AM Mon 68 69 NW 2 2835 4590 0 Blue 0
9 AM Mon 70 72 NW 2 4098 4590 0 Blue 0
10 AM Mon 72 76 NW 2 6078 4590 0 Blue 2
11 AM Mon 76 81 W 6 8237 6825 2235 Blue 7
12 Noon Mon 79 85 W 6 11138 8996 4406 Blue 11
1 PM Mon 81 88 W 6 12719 11014 6424 Blue 14
2 PM Mon 83 90 W 13 14880 12073 7483 Blue 16
3 PM Mon 84 90 W 13 14880 12073 7483 Blue 16
4 PM Mon 84 88 W 13 12719 11014 6424 Blue 14
5 PM Mon 84 86 W 13 11682 9758 5168 Blue 12
6 PM Mon 83 84 W 13 10575 8197 3607 Blue 10
7 PM Mon 82 82 W 13 9138 7547 2957 Blue 8
8 PM Mon 80 80 W 7 7934 6423 1833 Blue 6
9 PM Mon 74 74 W 7 5076 4590 0 Blue 0
10 PM Mon 71 71 W 7 3596 4590 0 Blue 0
11 PM Mon 69 69 SE 3 2835 4590 0 Blue 0
12 Midnight Tue 67 67 SE 3 2835 4590 0 Blue 0
1 AM Tue 65 65 SE 3 2835 4590 0 Blue 0
2 AM Tue 62 62 E 5 2835 4590 0 Blue 0
3 AM Tue 60 60 E 5 2835 4590 0 Blue 0
4 AM Tue 59 59 E 5 2835 4590 0 Blue 0
5 AM Tue 58 58 E 5 2835 4590 0 Blue 0
6 AM Tue 56 56 E 5 2835 4590 0 Blue 0
7 AM Tue 61 61 E 5 2835 4590 0 Blue 0
8 AM Tue 68 69 NE 3 2835 4590 0 Blue 0
9 AM Tue 70 72 NE 3 4098 4590 0 Blue 0
10 AM Tue 72 75 NE 3 5701 4590 0 Blue 1
11 AM Tue 76 81 N 5 8237 6825 2235 Blue 7
12 Noon Tue 79 86 N 5 11682 9758 5168 Blue 12
1 PM Tue 82 89 N 5 13968 11552 6962 Blue 15
2 PM Tue 84 91 NW 8 15163 12579 7989 Blue 17
3 PM Tue 85 91 NW 8 15163 12579 7989 Blue 17
4 PM Tue 85 89 NW 8 13968 11552 6962 Blue 15
5 PM Tue 85 88 W 9 12719 11014 6424 Blue 14
6 PM Tue 85 86 W 9 11682 9758 5168 Blue 12
7 PM Tue 84 84 W 9 10575 8197 3607 Blue 10
8 PM Tue 83 83 W 9 9891 7897 3307 Blue 9
9 PM Tue 79 79 W 9 7626 6055 1465 Blue 5
10 PM Tue 75 75 W 9 5701 4590 0 Blue 1
11 PM Tue 71 71 E 5 3596 4590 0 Blue 0
12 Midnight Wed 67 67 E 5 2835 4590 0 Blue 0
1 AM Wed 64 64 E 5 2835 4590 0 Blue 0
2 AM Wed 61 61 E 5 2835 4590 0 Blue 0
3 AM Wed 58 58 E 5 2835 4590 0 Blue 0
4 AM Wed 56 56 E 5 2835 4590 0 Blue 0
5 AM Wed 56 56 E 5 2835 4590 0 Blue 0
6 AM Wed 59 59 E 5 2835 4590 0 Blue 0
7 AM Wed 63 63 E 5 2835 4590 0 Blue 0
8 AM Wed 67 68 E 5 2835 4590 0 Blue 0
9 AM Wed 70 72 E 5 4098 4590 0 Blue 0
10 AM Wed 73 77 E 5 6450 5055 465 Blue 3
11 AM Wed 76 81 W 7 8237 6825 2235 Blue 7
12 Noon Wed 79 85 W 7 11138 8996 4406 Blue 11
1 PM Wed 82 89 W 7 13968 11552 6962 Blue 15
2 PM Wed 85 92 W 7 15443 13599 9009 Blue 18
3 PM Wed 86 92 W 7 15443 13599 9009 Blue 18
4 PM Wed 87 91 W 7 15163 12579 7989 Blue 17
5 PM Wed 87 90 W 12 14880 12073 7483 Blue 16
6 PM Wed 86 87 W 12 12208 10457 5867 Blue 13
7 PM Wed 84 84 W 12 10575 8197 3607 Blue 10
8 PM Wed 81 81 W 12 8237 6825 2235 Blue 7
9 PM Wed 78 78 W 12 6890 5682 1092 Blue 4
10 PM Wed 74 74 W 12 5076 4590 0 Blue 0
11 PM Wed 70 70 SE 3 3082 4590 0 Blue 0
12 Midnight Thu 67 67 SE 3 2835 4590 0 Blue 0
1 AM Thu 65 65 SE 3 2835 4590 0 Blue 0
2 AM Thu 62 62 SE 3 2835 4590 0 Blue 0
3 AM Thu 60 60 SE 3 2835 4590 0 Blue 0
4 AM Thu 58 58 SE 3 2835 4590 0 Blue 0
5 AM Thu 58 58 SE 5 2835 4590 0 Blue 0
6 AM Thu 61 61 SE 5 2835 4590 0 Blue 0
7 AM Thu 65 65 SE 5 2835 4590 0 Blue 0
8 AM Thu 69 70 SE 5 3082 4590 0 Blue 0
9 AM Thu 72 74 SE 5 5076 4590 0 Blue 0
10 AM Thu 75 79 SE 5 7626 6055 1465 Blue 5
11 AM Thu 77 83 W 7 9891 7897 3307 Blue 9
12 Noon Thu 80 88 W 7 12719 11014 6424 Blue 14
1 PM Thu 82 90 W 7 14880 12073 7483 Blue 16
2 PM Thu 85 93 W 7 15878 14671 10081 Blue 19
3 PM Thu 86 93 W 7 15878 14671 10081 Blue 19
4 PM Thu 86 91 W 7 15163 12579 7989 Blue 17
5 PM Thu 86 89 SW 12 13968 11552 6962 Blue 15
6 PM Thu 85 87 SW 12 12208 10457 5867 Blue 13
7 PM Thu 83 83 SW 12 9891 7897 3307 Blue 9
8 PM Thu 81 81 SW 12 8237 6825 2235 Blue 7
9 PM Thu 78 78 SW 12 6890 5682 1092 Blue 4
10 PM Thu 74 74 SW 12 5076 4590 0 Blue 0
11 PM Thu 70 70 SW 5 3082 4590 0 Blue 0
12 Midnight Fri 67 67 SW 5 2835 4590 0 Blue 0
1 AM Fri 64 64 SW 5 2835 4590 0 Blue 0
2 AM Fri 61 61 SW 5 2835 4590 0 Blue 0
3 AM Fri 58 58 SW 5 2835 4590 0 Blue 0
4 AM Fri 57 57 SW 5 2835 4590 0 Blue 0
5 AM Fri 57 57 S 5 2835 4590 0 Blue 0
6 AM Fri 60 60 S 5 2835 4590 0 Blue 0
7 AM Fri 65 65 S 5 2835 4590 0 Blue 0
8 AM Fri 68 69 S 5 2835 4590 0 Blue 0
9 AM Fri 71 73 S 5 4589 4590 0 Blue 0
10 AM Fri 72 76 S 5 6078 4590 0 Blue 2
11 AM Fri 74 80 SW 9 7934 6423 1833 Blue 6
12 Noon Fri 76 83 SW 9 9891 7897 3307 Blue 9
1 PM Fri 79 87 SW 9 12208 10457 5867 Blue 13
2 PM Fri 82 89 SW 9 13968 11552 6962 Blue 15
3 PM Fri 83 89 SW 9 13968 11552 6962 Blue 15
4 PM Fri 83 88 SW 9 12719 11014 6424 Blue 14
5 PM Fri 83 86 W 10 11682 9758 5168 Blue 12
6 PM Fri 82 83 W 10 9891 7897 3307 Blue 9
7 PM Fri 80 80 W 10 7934 6423 1833 Blue 6
8 PM Fri 78 78 W 10 6890 5682 1092 Blue 4
9 PM Fri 75 75 W 10 5701 4590 0 Blue 1
10 PM Fri 72 72 W 10 4098 4590 0 Blue 0
11 PM Fri 69 69 SW 5 2835 4590 0 Blue 0
12 Midnight Sat 66 66 SW 5 2835 4590 0 Blue 0
1 AM Sat 63 63 SW 5 2835 4590 0 Blue 0
2 AM Sat 60 60 SW 5 2835 4590 0 Blue 0
3 AM Sat 58 58 SW 5 2835 4590 0 Blue 0
4 AM Sat 56 56 SW 5 2835 4590 0 Blue 0
5 AM Sat 56 56 E 5 2835 4590 0 Blue 0
6 AM Sat 58 58 E 5 2835 4590 0 Blue 0
7 AM Sat 62 62 E 5 2835 4590 0 Blue 0
8 AM Sat 66 67 E 5 2835 4590 0 Blue 0
9 AM Sat 68 70 E 5 3082 4590 0 Blue 0
10 AM Sat 71 75 E 5 5701 4590 0 Blue 1
11 AM Sat 73 79 W 8 7626 6055 1465 Blue 5
12 Noon Sat 76 83 W 8 9891 7897 3307 Blue 9
1 PM Sat 79 86 W 8 11682 9758 5168 Blue 12
2 PM Sat 82 89 W 8 13968 11552 6962 Blue 15
3 PM Sat 83 89 W 8 13968 11552 6962 Blue 15
4 PM Sat 83 88 W 8 12719 11014 6424 Blue 14
5 PM Sat 83 86 W 10 11682 9758 5168 Blue 12
6 PM Sat 82 83 W 10 9891 7897 3307 Blue 9
7 PM Sat 80 80 W 10 7934 6423 1833 Blue 6
8 PM Sat 78 78 W 10 6890 5682 1092 Blue 4
9 PM Sat 75 75 W 10 5701 4590 0 Blue 1
10 PM Sat 71 71 W 10 3596 4590 0 Blue 0
11 PM Sat 67 67 SW 5 2835 4590 0 Blue 0
12 Midnight Sun 64 64 SW 5 2835 4590 0 Blue 0
1 AM Sun 62 62 SW 5 2835 4590 0 Blue 0
2 AM Sun 60 60 SW 5 2835 4590 0 Blue 0
3 AM Sun 57 57 SW 5 2835 4590 0 Blue 0
4 AM Sun 56 56 SW 5 2835 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 ac_soaring@yahoo.com