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:

 260912/1200

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 61 61 SE 8 12 4038 4590 0 Blue 0
1 AM Sat 59 59 SE 6 10 4038 4590 0 Blue 0
2 AM Sat 58 58 SE 5 9 4038 4590 0 Blue 0
3 AM Sat 57 57 ESE 5 8 4038 4590 0 Blue 0
4 AM Sat 55 55 ESE 5 8 4038 4590 0 Blue 0
5 AM Sat 54 54 ESE 4 6 4038 4590 0 Blue 0
6 AM Sat 53 53 ESE 4 6 4038 4590 0 Blue 0
7 AM Sat 52 52 E 4 6 4038 4590 0 Blue 0
8 AM Sat 56 56 E 5 10 4038 4590 0 Blue 0
9 AM Sat 60 61 N 5 10 4038 4590 0 Blue 0
10 AM Sat 65 68 WNW 6 13 4038 4590 0 Blue 0
11 AM Sat 69 73 W 8 17 4202 4590 0 Blue 2
12 Noon Sat 73 78 SW 11 24 5443 4590 0 Blue 7
1 PM Sat 75 80 SW 12 29 8166 4947 357 Blue 9
2 PM Sat 75 79 SW 14 32 7168 4590 0 Blue 8
3 PM Sat 76 80 SW 16 34 8166 4947 357 Blue 9
4 PM Sat 75 78 SW 17 34 5443 4590 0 Blue 7
5 PM Sat 75 76 SW 16 33 4587 4590 0 Blue 5
6 PM Sat 72 72 SW 17 36 4141 4590 0 Blue 1
7 PM Sat 70 70 SW 19 42 4038 4590 0 Blue 0
8 PM Sat 67 67 WSW 19 43 4038 4590 0 Blue 0
9 PM Sat 63 63 SW 19 41 4038 4590 0 Blue 0
10 PM Sat 59 59 SW 17 35 4038 4590 0 Blue 0
11 PM Sat 56 56 SW 13 29 4038 4590 0 Blue 0
12 Midnight Sun 54 54 SSW 10 23 4038 4590 0 Blue 0
1 AM Sun 51 51 S 6 13 4038 4590 0 Blue 0
2 AM Sun 50 50 S 3 5 4038 4590 0 Blue 0
3 AM Sun 48 48 S 2 3 4038 4590 0 Blue 0
4 AM Sun 44 44 SSE 1 2 4038 4590 0 Blue 0
5 AM Sun 42 42 SE 1 1 4038 4590 0 Blue 0
6 AM Sun 42 42 SE 1 1 4038 4590 0 Blue 0
7 AM Sun 40 40 SE 1 1 4038 4590 0 Blue 0
8 AM Sun 44 44 NNE 3 6 4038 4590 0 Blue 0
9 AM Sun 48 49 NNE 3 6 4038 4590 0 Blue 0
10 AM Sun 53 55 NNE 3 6 4038 4590 0 Blue 0
11 AM Sun 56 60 NNW 5 13 4038 4590 0 Blue 0
12 Noon Sun 60 65 NNW 5 13 4038 4590 0 Blue 0
1 PM Sun 62 68 NNW 5 13 4038 4590 0 Blue 0
2 PM Sun 65 70 NNW 6 16 4038 4590 0 Blue 0
3 PM Sun 66 70 NNW 6 16 4038 4590 0 Blue 0
4 PM Sun 67 70 NNW 6 16 4038 4590 0 Blue 0
5 PM Sun 67 68 NNW 5 14 4038 4590 0 Blue 0
6 PM Sun 65 65 NNW 5 14 4038 4590 0 Blue 0
7 PM Sun 63 63 NNW 5 14 4038 4590 0 Blue 0
8 PM Sun 60 60 NE 4 8 4038 4590 0 Blue 0
9 PM Sun 57 57 NE 4 8 4038 4590 0 Blue 0
10 PM Sun 54 54 NE 4 8 4038 4590 0 Blue 0
11 PM Sun 51 51 E 3 6 4038 4590 0 Blue 0
12 Midnight Mon 49 49 E 3 6 4038 4590 0 Blue 0
1 AM Mon 48 48 E 3 6 4038 4590 0 Blue 0
2 AM Mon 46 46 E 2 3 4038 4590 0 Blue 0
3 AM Mon 44 44 E 2 3 4038 4590 0 Blue 0
4 AM Mon 42 42 E 2 3 4038 4590 0 Blue 0
5 AM Mon 41 41 ESE 3 4 4038 4590 0 Blue 0
6 AM Mon 40 40 ESE 3 4 4038 4590 0 Blue 0
7 AM Mon 42 42 ESE 3 4 4038 4590 0 Blue 0
8 AM Mon 44 44 E 5 10 4038 4590 0 Blue 0
9 AM Mon 49 50 E 5 10 4038 4590 0 Blue 0
10 AM Mon 55 58 E 5 10 4038 4590 0 Blue 0
11 AM Mon 62 66 NE 5 11 4038 4590 0 Blue 0
12 Noon Mon 67 72 NE 5 11 4141 4590 0 Blue 1
1 PM Mon 71 77 NE 5 11 4958 4590 0 Blue 6
2 PM Mon 74 79 N 4 11 7168 4590 0 Blue 8
3 PM Mon 76 80 N 4 11 8166 4947 357 Blue 9
4 PM Mon 77 80 N 4 11 8166 4947 357 Blue 9
5 PM Mon 76 77 NNW 5 12 4958 4590 0 Blue 6
6 PM Mon 73 73 NNW 5 12 4202 4590 0 Blue 2
7 PM Mon 70 70 NNW 5 12 4038 4590 0 Blue 0
8 PM Mon 66 66 WSW 1 3 4038 4590 0 Blue 0
9 PM Mon 62 62 WSW 1 3 4038 4590 0 Blue 0
10 PM Mon 58 58 WSW 1 3 4038 4590 0 Blue 0
11 PM Mon 55 55 SSE 3 4 4038 4590 0 Blue 0
12 Midnight Tue 53 53 SSE 3 4 4038 4590 0 Blue 0
1 AM Tue 52 52 SSE 3 4 4038 4590 0 Blue 0
2 AM Tue 50 50 SSE 3 5 4038 4590 0 Blue 0
3 AM Tue 48 48 SSE 3 5 4038 4590 0 Blue 0
4 AM Tue 46 46 SSE 3 5 4038 4590 0 Blue 0
5 AM Tue 45 45 SE 2 3 4038 4590 0 Blue 0
6 AM Tue 45 45 SE 2 3 4038 4590 0 Blue 0
7 AM Tue 46 46 SE 2 3 4038 4590 0 Blue 0
8 AM Tue 49 49 SE 4 8 4038 4590 0 Blue 0
9 AM Tue 54 55 SE 4 8 4038 4590 0 Blue 0
10 AM Tue 60 62 SE 4 8 4038 4590 0 Blue 0
11 AM Tue 65 69 NNW 4 8 4038 4590 0 Blue 0
12 Noon Tue 69 74 NNW 4 8 4280 4590 0 Blue 3
1 PM Tue 72 78 NNW 4 8 5443 4590 0 Blue 7
2 PM Tue 75 80 WNW 6 14 8166 4947 357 Blue 9
3 PM Tue 76 80 WNW 6 14 8166 4947 357 Blue 9
4 PM Tue 77 80 WNW 6 14 8166 4947 357 Blue 9
5 PM Tue 76 77 W 8 16 4958 4590 0 Blue 6
6 PM Tue 73 73 W 8 16 4202 4590 0 Blue 2
7 PM Tue 69 69 W 8 16 4038 4590 0 Blue 0
8 PM Tue 66 66 SW 2 3 4038 4590 0 Blue 0
9 PM Tue 62 62 SW 2 3 4038 4590 0 Blue 0
10 PM Tue 59 59 SW 2 3 4038 4590 0 Blue 0
11 PM Tue 56 56 SSE 4 8 4038 4590 0 Blue 0
12 Midnight Wed 54 54 SSE 4 8 4038 4590 0 Blue 0
1 AM Wed 52 52 SSE 4 8 4038 4590 0 Blue 0
2 AM Wed 51 51 SSE 3 4 4038 4590 0 Blue 0
3 AM Wed 50 50 SSE 3 4 4038 4590 0 Blue 0
4 AM Wed 48 48 SSE 3 4 4038 4590 0 Blue 0
5 AM Wed 48 48 SE 2 3 4038 4590 0 Blue 0
6 AM Wed 48 48 SE 2 3 4038 4590 0 Blue 0
7 AM Wed 49 49 SE 2 3 4038 4590 0 Blue 0
8 AM Wed 51 51 ESE 5 10 4038 4590 0 Blue 0
9 AM Wed 56 57 ESE 5 10 4038 4590 0 Blue 0
10 AM Wed 62 64 ESE 5 10 4038 4590 0 Blue 0
11 AM Wed 68 72 N 4 9 4141 4590 0 Blue 1
12 Noon Wed 72 77 N 4 9 4958 4590 0 Blue 6
1 PM Wed 75 80 N 4 9 8166 4947 357 Blue 9
2 PM Wed 77 82 WNW 4 12 10679 6977 2387 Blue 11
3 PM Wed 78 82 WNW 4 12 10679 6977 2387 Blue 11
4 PM Wed 78 81 WNW 4 12 10301 5421 831 Blue 10
5 PM Wed 77 78 W 5 12 5443 4590 0 Blue 7
6 PM Wed 74 74 W 5 12 4280 4590 0 Blue 3
7 PM Wed 71 71 W 5 12 4038 4590 0 Blue 0
8 PM Wed 67 67 SSW 2 3 4038 4590 0 Blue 0
9 PM Wed 63 63 SSW 2 3 4038 4590 0 Blue 0
10 PM Wed 60 60 SSW 2 3 4038 4590 0 Blue 0
11 PM Wed 57 57 SSE 4 9 4038 4590 0 Blue 0
12 Midnight Thu 55 55 SSE 4 9 4038 4590 0 Blue 0
1 AM Thu 54 54 SSE 4 9 4038 4590 0 Blue 0
2 AM Thu 53 53 SSE 3 4 4038 4590 0 Blue 0
3 AM Thu 52 52 SSE 3 4 4038 4590 0 Blue 0
4 AM Thu 50 50 SSE 3 4 4038 4590 0 Blue 0
5 AM Thu 50 50 SSE 3 4 4038 4590 0 Blue 0
6 AM Thu 50 50 SSE 3 4 4038 4590 0 Blue 0
7 AM Thu 51 51 SSE 3 4 4038 4590 0 Blue 0
8 AM Thu 54 54 SE 3 4 4038 4590 0 Blue 0
9 AM Thu 59 60 SE 3 4 4038 4590 0 Blue 0
10 AM Thu 65 67 SE 3 4 4038 4590 0 Blue 0
11 AM Thu 70 74 NNW 3 8 4280 4590 0 Blue 3
12 Noon Thu 74 79 NNW 3 8 7168 4590 0 Blue 8
1 PM Thu 76 81 NNW 3 8 10301 5421 831 Blue 10
2 PM Thu 78 83 WNW 4 13 11525 8115 3525 Blue 12
3 PM Thu 79 83 WNW 4 13 11525 8115 3525 Blue 12
4 PM Thu 78 81 WNW 4 13 10301 5421 831 Blue 10
5 PM Thu 77 78 W 8 16 5443 4590 0 Blue 7
6 PM Thu 75 75 W 8 16 4359 4590 0 Blue 4
7 PM Thu 72 72 W 8 16 4141 4590 0 Blue 1
8 PM Thu 68 68 WSW 2 3 4038 4590 0 Blue 0
9 PM Thu 64 64 WSW 2 3 4038 4590 0 Blue 0
10 PM Thu 61 61 WSW 2 3 4038 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]