Detailed Predictions for: Hat Creek Rim
Launch Lat, Long, Altitude (f): 40.843037, -121.427406, 4590
LZ Altitude (f): 3575
Sounding

Station:

 KOAK

Date/Time UTC:

 250322/1200

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 Sat 40 40 S 3 8 4012 4590 0 Blue 0
1 AM Sat 40 40 S 3 8 4012 4590 0 Blue 0
2 AM Sat 39 39 S 2 6 4012 4590 0 Blue 0
3 AM Sat 39 39 S 2 5 4012 4590 0 Blue 0
4 AM Sat 38 38 S 2 4 4012 4590 0 Blue 0
5 AM Sat 38 38 S 2 3 4012 4590 0 Blue 0
6 AM Sat 37 37 S 2 3 4012 4590 0 Blue 0
7 AM Sat 38 38 SSE 1 3 4012 4590 0 Blue 0
8 AM Sat 38 38 S 1 3 4012 4590 0 Blue 0
9 AM Sat 39 39 S 1 3 4012 4590 0 Blue 0
10 AM Sat 41 41 SSW 2 3 4012 4590 0 Blue 0
11 AM Sat 42 42 SW 2 5 4012 4590 0 Blue 0
12 Noon Sat 43 44 WSW 2 6 4012 4590 0 Blue 0
1 PM Sat 44 45 W 3 6 4012 4590 0 Blue 0
2 PM Sat 45 45 W 3 9 4012 4590 0 Blue 0
3 PM Sat 47 47 W 4 9 5465 4590 0 Blue 1
4 PM Sat 47 47 W 4 8 5465 4590 0 Blue 1
5 PM Sat 48 48 W 3 8 5889 4590 0 Blue 2
6 PM Sat 48 48 WNW 2 5 5889 4590 0 Blue 2
7 PM Sat 47 47 NW 2 3 5465 4590 0 Blue 1
8 PM Sat 46 46 N 1 2 5041 4590 0 Blue 0
9 PM Sat 43 43 E 1 2 4012 4590 0 Blue 0
10 PM Sat 41 41 ESE 1 1 4012 4590 0 Blue 0
11 PM Sat 40 40 SE 1 1 4012 4590 0 Blue 0
12 Midnight Sun 39 39 ESE 1 1 4012 4590 0 Blue 0
1 AM Sun 38 38 ESE 1 2 4012 4590 0 Blue 0
2 AM Sun 37 37 ESE 1 2 4012 4590 0 Blue 0
3 AM Sun 36 36 ESE 1 2 4012 4590 0 Blue 0
4 AM Sun 34 34 ESE 1 2 4012 4590 0 Blue 0
5 AM Sun 34 34 SE 1 3 4012 4590 0 Blue 0
6 AM Sun 34 34 SE 1 3 4012 4590 0 Blue 0
7 AM Sun 33 33 SE 1 3 4012 4590 0 Blue 0
8 AM Sun 34 34 ESE 2 3 4012 4590 0 Blue 0
9 AM Sun 38 38 ESE 2 3 4012 4590 0 Blue 0
10 AM Sun 44 45 ESE 2 3 4012 4590 0 Blue 0
11 AM Sun 48 51 NNE 2 4 6405 5864 1274 Blue 5
12 Noon Sun 52 55 NNE 2 4 7210 6533 1943 Blue 9
1 PM Sun 55 59 NNE 2 4 8280 7449 2859 Blue 13
2 PM Sun 58 61 N 3 8 8821 7976 3386 Blue 15
3 PM Sun 60 62 N 3 8 9088 8243 3653 Blue 16
4 PM Sun 61 62 N 3 8 9088 8243 3653 Blue 16
5 PM Sun 61 62 N 3 8 9088 8243 3653 Blue 16
6 PM Sun 60 60 N 3 8 8551 7713 3123 Blue 14
7 PM Sun 58 58 N 3 8 8010 7183 2593 Blue 12
8 PM Sun 55 55 NE 2 4 7210 6533 1943 Blue 9
9 PM Sun 53 53 NE 2 4 6683 6256 1666 Blue 7
10 PM Sun 50 50 NE 2 4 6266 5446 856 Blue 4
11 PM Sun 47 47 E 2 3 5465 4590 0 Blue 1
12 Midnight Mon 45 45 E 2 3 4012 4590 0 Blue 0
1 AM Mon 44 44 E 2 3 4012 4590 0 Blue 0
2 AM Mon 43 43 E 2 3 4012 4590 0 Blue 0
3 AM Mon 42 42 E 2 3 4012 4590 0 Blue 0
4 AM Mon 41 41 E 2 3 4012 4590 0 Blue 0
5 AM Mon 40 40 E 2 3 4012 4590 0 Blue 0
6 AM Mon 40 40 E 2 3 4012 4590 0 Blue 0
7 AM Mon 40 40 E 2 3 4012 4590 0 Blue 0
8 AM Mon 41 41 ESE 2 4 4012 4590 0 Blue 0
9 AM Mon 45 46 ESE 2 4 5041 4590 0 Blue 0
10 AM Mon 50 52 ESE 2 4 6544 6117 1527 Blue 6
11 AM Mon 55 58 E 2 5 8010 7183 2593 Blue 12
12 Noon Mon 59 63 E 2 5 9355 8511 3921 Blue 17
1 PM Mon 62 67 E 2 5 10387 9571 4981 Blue 21
2 PM Mon 65 70 NNE 3 6 11108 10336 5746 Blue 24
3 PM Mon 67 71 NNE 3 6 11728 10576 5986 Blue 25
4 PM Mon 68 70 NNE 3 6 11108 10336 5746 Blue 24
5 PM Mon 68 69 N 2 6 10869 10092 5502 Blue 23
6 PM Mon 66 66 N 2 6 10144 9308 4718 Blue 20
7 PM Mon 63 63 N 2 6 9355 8511 3921 Blue 17
8 PM Mon 60 60 E 2 3 8551 7713 3123 Blue 14
9 PM Mon 57 57 E 2 3 7745 6916 2326 Blue 11
10 PM Mon 54 54 E 2 3 6942 6394 1804 Blue 8
11 PM Mon 51 51 SE 2 4 6405 5864 1274 Blue 5
12 Midnight Tue 49 49 SE 2 4 6126 5028 438 Blue 3
1 AM Tue 48 48 SE 2 4 5889 4590 0 Blue 2
2 AM Tue 47 47 SE 2 3 5465 4590 0 Blue 1
3 AM Tue 46 46 SE 2 3 5041 4590 0 Blue 0
4 AM Tue 45 45 SE 2 3 4012 4590 0 Blue 0
5 AM Tue 44 44 SE 2 4 4012 4590 0 Blue 0
6 AM Tue 43 43 SE 2 4 4012 4590 0 Blue 0
7 AM Tue 41 41 SE 2 4 4012 4590 0 Blue 0
8 AM Tue 42 42 SE 3 4 4012 4590 0 Blue 0
9 AM Tue 47 48 SE 3 4 5889 4590 0 Blue 2
10 AM Tue 54 56 SE 3 4 7478 6671 2081 Blue 10
11 AM Tue 60 63 E 2 5 9355 8511 3921 Blue 17
12 Noon Tue 64 68 E 2 5 10628 9832 5242 Blue 22
1 PM Tue 67 72 E 2 5 11957 10814 6224 Blue 26
2 PM Tue 69 73 W 5 11 12409 11052 6462 White 27
3 PM Tue 71 74 W 5 11 12614 11456 6866 White 28
4 PM Tue 71 73 W 5 11 12409 11052 6462 White 27
5 PM Tue 70 71 W 8 14 11728 10576 5986 Blue 25
6 PM Tue 67 67 W 8 14 10387 9571 4981 Blue 21
7 PM Tue 63 63 W 8 14 9355 8511 3921 Blue 17
8 PM Tue 59 59 SSW 3 6 8280 7449 2859 Blue 13
9 PM Tue 56 56 SSW 3 6 7478 6671 2081 Blue 10
10 PM Tue 54 54 SSW 3 6 6942 6394 1804 Blue 8
11 PM Tue 52 52 S 3 5 6544 6117 1527 Blue 6
12 Midnight Wed 51 51 S 3 5 6405 5864 1274 Blue 5
1 AM Wed 50 50 S 3 5 6266 5446 856 Blue 4
2 AM Wed 49 49 SSE 3 5 6126 5028 438 Blue 3
3 AM Wed 48 48 SSE 3 5 5889 4590 0 Blue 2
4 AM Wed 46 46 SSE 3 5 5041 4590 0 Blue 0
5 AM Wed 45 45 SSE 3 5 4012 4590 0 Blue 0
6 AM Wed 45 45 SSE 3 5 4012 4590 0 Blue 0
7 AM Wed 45 45 SSE 3 5 4012 4590 0 Blue 0
8 AM Wed 46 46 S 5 10 5041 4590 0 Blue 0
9 AM Wed 50 50 S 5 10 6266 5446 856 Blue 4
10 AM Wed 55 56 S 5 10 7478 6671 2081 Blue 10
11 AM Wed 60 62 SW 9 19 9088 8243 3653 Blue 16
12 Noon Wed 62 64 SW 9 19 9620 8778 4188 Blue 18
1 PM Wed 64 66 SW 9 19 10144 9308 4718 Blue 20
2 PM Wed 64 66 SW 16 31 10144 9308 4718 Blue 20
3 PM Wed 64 66 SW 16 31 10144 9308 4718 Blue 20
4 PM Wed 64 65 SW 16 31 9883 9044 4454 Blue 19
5 PM Wed 62 62 SSW 19 37 9088 8243 3653 Blue 16
6 PM Wed 59 59 SSW 19 37 8280 7449 2859 Blue 13
7 PM Wed 55 55 SSW 19 37 7210 6533 1943 Blue 9
8 PM Wed 52 52 SSW 18 35 6544 6117 1527 Blue 6
9 PM Wed 50 50 SSW 18 35 6266 5446 856 Blue 4
10 PM Wed 49 49 SSW 18 35 6126 5028 438 Blue 3
11 PM Wed 48 48 SSW 18 34 5889 4590 0 Blue 2
12 Midnight Thu 47 47 SSW 18 34 5465 4590 0 Blue 1
1 AM Thu 45 45 SSW 18 34 4012 4590 0 Blue 0
2 AM Thu 44 44 SSW 14 28 4012 4590 0 Blue 0
3 AM Thu 42 42 SSW 14 28 4012 4590 0 Blue 0
4 AM Thu 41 41 SSW 14 28 4012 4590 0 Blue 0
5 AM Thu 39 39 SW 11 21 4012 4590 0 Blue 0
6 AM Thu 38 38 SW 11 21 4012 4590 0 Blue 0
7 AM Thu 37 37 SW 11 21 4012 4590 0 Blue 0
8 AM Thu 37 37 SW 10 20 4012 4590 0 Blue 0
9 AM Thu 38 38 SW 10 20 4012 4590 0 Blue 0
10 AM Thu 40 41 SW 10 20 4012 4590 0 Blue 0
11 AM Thu 42 43 SW 12 24 4012 4590 0 Blue 0
12 Noon Thu 44 45 SW 12 24 4012 4590 0 Blue 0
1 PM Thu 46 47 SW 12 24 5465 4590 0 Blue 1
2 PM Thu 47 48 WSW 14 27 5889 4590 0 Blue 2
3 PM Thu 48 49 WSW 14 27 6126 5028 438 Blue 3
4 PM Thu 48 48 WSW 14 27 5889 4590 0 Blue 2
5 PM Thu 48 48 WSW 14 27 5889 4590 0 Blue 2
6 PM Thu 46 46 WSW 14 27 5041 4590 0 Blue 0
7 PM Thu 43 43 WSW 14 27 4012 4590 0 Blue 0
8 PM Thu 41 41 WSW 10 19 4012 4590 0 Blue 0
9 PM Thu 40 40 WSW 10 19 4012 4590 0 Blue 0
10 PM Thu 39 39 WSW 10 19 4012 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 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]