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

Station:

KOAK

Date/Time:

22 MAR 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 Fri 32 32 SW 6 3930 4590 0 Blue 0
6 AM Fri 32 32 SW 6 3930 4590 0 Blue 0
7 AM Fri 33 33 SW 6 3930 4590 0 Blue 0
8 AM Fri 35 35 E 5 3930 4590 0 Blue 0
9 AM Fri 37 37 E 5 3930 4590 0 Blue 0
10 AM Fri 41 42 E 5 4461 4590 0 Blue 1
11 AM Fri 44 44 SW 7 4772 4590 0 Blue 3
12 Noon Fri 46 46 SW 7 5330 4614 24 Blue 5
1 PM Fri 47 47 SW 7 5835 4769 179 Blue 6
2 PM Fri 47 47 SW 8 5835 4769 179 Blue 6
3 PM Fri 46 46 SW 8 5330 4614 24 Blue 5
4 PM Fri 45 45 SW 8 5040 4590 0 Blue 4
5 PM Fri 44 44 W 7 4772 4590 0 Blue 3
6 PM Fri 43 43 W 7 4617 4590 0 Blue 2
7 PM Fri 42 42 W 7 4461 4590 0 Blue 1
8 PM Fri 41 41 NW 3 4151 4590 0 Blue 0
9 PM Fri 40 40 NW 3 3930 4590 0 Blue 0
10 PM Fri 39 39 NW 3 3930 4590 0 Blue 0
11 PM Fri 38 38 NW 3 3930 4590 0 Blue 0
12 Midnight Sat 38 38 NW 3 3930 4590 0 Blue 0
1 AM Sat 38 38 NW 3 3930 4590 0 Blue 0
2 AM Sat 38 38 N 2 3930 4590 0 Blue 0
3 AM Sat 37 37 N 2 3930 4590 0 Blue 0
4 AM Sat 36 36 N 2 3930 4590 0 Blue 0
5 AM Sat 35 35 N 2 3930 4590 0 Blue 0
6 AM Sat 34 34 N 2 3930 4590 0 Blue 0
7 AM Sat 34 34 N 2 3930 4590 0 Blue 0
8 AM Sat 35 35 NW 2 3930 4590 0 Blue 0
9 AM Sat 36 36 NW 2 3930 4590 0 Blue 0
10 AM Sat 38 38 NW 2 3930 4590 0 Blue 0
11 AM Sat 41 42 W 5 4461 4590 0 Blue 1
12 Noon Sat 44 45 W 5 5040 4590 0 Blue 4
1 PM Sat 46 47 W 5 5835 4769 179 Blue 6
2 PM Sat 47 48 W 7 6327 5033 443 Blue 7
3 PM Sat 48 49 W 7 6807 5309 719 Blue 8
4 PM Sat 48 48 W 7 6327 5033 443 Blue 7
5 PM Sat 46 46 W 7 5330 4614 24 Blue 5
6 PM Sat 44 44 W 7 4772 4590 0 Blue 3
7 PM Sat 42 42 W 7 4461 4590 0 Blue 1
8 PM Sat 40 40 W 7 3930 4590 0 Blue 0
9 PM Sat 38 38 W 7 3930 4590 0 Blue 0
10 PM Sat 37 37 W 7 3930 4590 0 Blue 0
11 PM Sat 35 35 S 3 3930 4590 0 Blue 0
12 Midnight Sun 34 34 S 3 3930 4590 0 Blue 0
1 AM Sun 34 34 S 3 3930 4590 0 Blue 0
2 AM Sun 33 33 S 3 3930 4590 0 Blue 0
3 AM Sun 33 33 S 3 3930 4590 0 Blue 0
4 AM Sun 33 33 S 3 3930 4590 0 Blue 0
5 AM Sun 32 32 SE 3 3930 4590 0 Blue 0
6 AM Sun 31 31 SE 3 3930 4590 0 Blue 0
7 AM Sun 31 31 SE 3 3930 4590 0 Blue 0
8 AM Sun 32 32 SE 3 3930 4590 0 Blue 0
9 AM Sun 36 36 SE 3 3930 4590 0 Blue 0
10 AM Sun 41 42 SE 3 4461 4590 0 Blue 1
11 AM Sun 45 47 S 5 5835 4769 179 Blue 6
12 Noon Sun 49 51 S 5 7843 6291 1701 Blue 10
1 PM Sun 52 55 S 5 9600 8262 3672 Blue 14
2 PM Sun 54 57 S 5 11009 8821 4231 Blue 16
3 PM Sun 55 57 S 5 11009 8821 4231 Blue 16
4 PM Sun 56 57 S 5 11009 8821 4231 Blue 16
5 PM Sun 55 55 S 6 9600 8262 3672 Blue 14
6 PM Sun 51 51 S 6 7843 6291 1701 Blue 10
7 PM Sun 46 46 S 6 5330 4614 24 Blue 5
8 PM Sun 42 42 S 6 4461 4590 0 Blue 1
9 PM Sun 40 40 S 6 3930 4590 0 Blue 0
10 PM Sun 40 40 S 6 3930 4590 0 Blue 0
11 PM Sun 40 40 S 6 3930 4590 0 Blue 0
12 Midnight Mon 39 39 S 6 3930 4590 0 Blue 0
1 AM Mon 38 38 S 6 3930 4590 0 Blue 0
2 AM Mon 37 37 S 6 3930 4590 0 Blue 0
3 AM Mon 36 36 S 6 3930 4590 0 Blue 0
4 AM Mon 36 36 S 6 3930 4590 0 Blue 0
5 AM Mon 36 36 S 9 3930 4590 0 Blue 0
6 AM Mon 35 35 S 9 3930 4590 0 Blue 0
7 AM Mon 35 35 S 9 3930 4590 0 Blue 0
8 AM Mon 36 36 S 9 3930 4590 0 Blue 0
9 AM Mon 37 37 S 9 3930 4590 0 Blue 0
10 AM Mon 40 40 S 9 3930 4590 0 Blue 0
11 AM Mon 43 43 S 10 4617 4590 0 Blue 2
12 Noon Mon 45 45 S 10 5040 4590 0 Blue 4
1 PM Mon 47 47 S 10 5835 4769 179 Blue 6
2 PM Mon 48 48 S 10 6327 5033 443 Blue 7
3 PM Mon 49 49 S 10 6807 5309 719 Blue 8
4 PM Mon 49 49 S 10 6807 5309 719 Blue 8
5 PM Mon 48 48 SW 9 6327 5033 443 Blue 7
6 PM Mon 46 46 SW 9 5330 4614 24 Blue 5
7 PM Mon 43 43 SW 9 4617 4590 0 Blue 2
8 PM Mon 41 41 SW 9 4151 4590 0 Blue 0
9 PM Mon 39 39 SW 9 3930 4590 0 Blue 0
10 PM Mon 38 38 SW 9 3930 4590 0 Blue 0
11 PM Mon 38 38 S 3 3930 4590 0 Blue 0
12 Midnight Tue 37 37 S 3 3930 4590 0 Blue 0
1 AM Tue 37 37 S 3 3930 4590 0 Blue 0
2 AM Tue 36 36 S 3 3930 4590 0 Blue 0
3 AM Tue 36 36 S 3 3930 4590 0 Blue 0
4 AM Tue 35 35 S 3 3930 4590 0 Blue 0
5 AM Tue 35 35 SE 5 3930 4590 0 Blue 0
6 AM Tue 35 35 SE 5 3930 4590 0 Blue 0
7 AM Tue 36 36 SE 5 3930 4590 0 Blue 0
8 AM Tue 37 37 SE 5 3930 4590 0 Blue 0
9 AM Tue 39 39 SE 5 3930 4590 0 Blue 0
10 AM Tue 41 41 SE 5 4151 4590 0 Blue 0
11 AM Tue 44 44 S 8 4772 4590 0 Blue 3
12 Noon Tue 46 46 S 8 5330 4614 24 Blue 5
1 PM Tue 48 49 S 8 6807 5309 719 Blue 8
2 PM Tue 49 49 S 8 6807 5309 719 Blue 8
3 PM Tue 49 49 S 8 6807 5309 719 Blue 8
4 PM Tue 49 49 S 8 6807 5309 719 Blue 8
5 PM Tue 47 47 SW 9 5835 4769 179 Blue 6
6 PM Tue 46 46 SW 9 5330 4614 24 Blue 5
7 PM Tue 44 44 SW 9 4772 4590 0 Blue 3
8 PM Tue 43 43 SW 9 4617 4590 0 Blue 2
9 PM Tue 41 41 SW 9 4151 4590 0 Blue 0
10 PM Tue 41 41 SW 9 4151 4590 0 Blue 0
11 PM Tue 40 40 S 5 3930 4590 0 Blue 0
12 Midnight Wed 40 40 S 5 3930 4590 0 Blue 0
1 AM Wed 39 39 S 5 3930 4590 0 Blue 0
2 AM Wed 39 39 S 5 3930 4590 0 Blue 0
3 AM Wed 39 39 S 5 3930 4590 0 Blue 0
4 AM Wed 38 38 S 5 3930 4590 0 Blue 0
5 AM Wed 38 38 S 6 3930 4590 0 Blue 0
6 AM Wed 37 37 S 6 3930 4590 0 Blue 0
7 AM Wed 36 36 S 6 3930 4590 0 Blue 0
8 AM Wed 36 36 S 6 3930 4590 0 Blue 0
9 AM Wed 38 38 S 6 3930 4590 0 Blue 0
10 AM Wed 40 40 S 6 3930 4590 0 Blue 0
11 AM Wed 43 43 S 8 4617 4590 0 Blue 2
12 Noon Wed 45 45 S 8 5040 4590 0 Blue 4
1 PM Wed 46 46 S 8 5330 4614 24 Blue 5
2 PM Wed 46 46 S 8 5330 4614 24 Blue 5
3 PM Wed 46 46 S 8 5330 4614 24 Blue 5
4 PM Wed 45 45 S 8 5040 4590 0 Blue 4
5 PM Wed 44 44 SW 9 4772 4590 0 Blue 3
6 PM Wed 42 42 SW 9 4461 4590 0 Blue 1
7 PM Wed 40 40 SW 9 3930 4590 0 Blue 0
8 PM Wed 39 39 SW 9 3930 4590 0 Blue 0
9 PM Wed 38 38 SW 9 3930 4590 0 Blue 0
10 PM Wed 37 37 SW 9 3930 4590 0 Blue 0
11 PM Wed 37 37 S 6 3930 4590 0 Blue 0
12 Midnight Thu 36 36 S 6 3930 4590 0 Blue 0
1 AM Thu 36 36 S 6 3930 4590 0 Blue 0
2 AM Thu 36 36 S 6 3930 4590 0 Blue 0
3 AM Thu 36 36 S 6 3930 4590 0 Blue 0
4 AM Thu 35 35 S 6 3930 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