Detailed Predictions for: Slick Rock
Launch Altitude (f): 5075
LZ Altitude (f): 1140
Sounding

Station:

KVBG

Date/Time:

16 FEB 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)
4 AM Sat 32 32 NW 3 3294 5075 0 Blue 0
5 AM Sat 32 32 NW 3 3294 5075 0 Blue 0
6 AM Sat 32 32 NW 3 3294 5075 0 Blue 0
7 AM Sat 31 31 NW 3 3294 5075 0 Blue 0
8 AM Sat 32 32 NW 3 3294 5075 0 Blue 0
9 AM Sat 38 38 NW 3 5273 5075 0 White 4
10 AM Sat 39 39 W 5 5492 5132 57 White 5
11 AM Sat 40 41 W 5 5929 5783 708 White 7
12 Noon Sat 40 41 W 5 5929 5783 708 White 7
1 PM Sat 41 42 W 6 6146 6146 1071 White 8
2 PM Sat 40 40 W 6 5711 5459 384 White 6
3 PM Sat 40 40 W 6 5711 5459 384 White 6
4 PM Sat 38 38 W 6 5273 5075 0 White 4
5 PM Sat 35 35 W 6 4611 5075 0 White 1
6 PM Sat 34 34 W 6 4213 5075 0 Blue 0
7 PM Sat 35 35 NW 5 4611 5075 0 White 1
8 PM Sat 35 35 NW 5 4611 5075 0 White 1
9 PM Sat 35 35 NW 5 4611 5075 0 White 1
10 PM Sat 34 34 W 3 4213 5075 0 Blue 0
11 PM Sat 35 35 W 3 4611 5075 0 White 1
12 Midnight Sun 33 33 W 3 3294 5075 0 Blue 0
1 AM Sun 32 32 NW 2 3294 5075 0 Blue 0
2 AM Sun 32 32 NW 2 3294 5075 0 Blue 0
3 AM Sun 31 31 NW 2 3294 5075 0 Blue 0
4 AM Sun 31 31 NW 2 3294 5075 0 Blue 0
5 AM Sun 31 31 NW 2 3294 5075 0 Blue 0
6 AM Sun 31 31 NW 2 3294 5075 0 Blue 0
7 AM Sun 30 30 S 2 3294 5075 0 Blue 0
8 AM Sun 30 30 S 2 3294 5075 0 Blue 0
9 AM Sun 36 36 S 2 4834 5075 0 White 2
10 AM Sun 37 37 W 6 5054 5075 0 White 3
11 AM Sun 37 37 W 6 5054 5075 0 White 3
12 Noon Sun 38 38 W 6 5273 5075 0 White 4
1 PM Sun 38 38 W 5 5273 5075 0 White 4
2 PM Sun 38 38 W 5 5273 5075 0 White 4
3 PM Sun 37 37 W 5 5054 5075 0 White 3
4 PM Sun 36 36 W 5 4834 5075 0 White 2
5 PM Sun 35 35 W 5 4611 5075 0 White 1
6 PM Sun 33 33 W 5 3294 5075 0 Blue 0
7 PM Sun 32 32 W 2 3294 5075 0 Blue 0
8 PM Sun 31 31 W 2 3294 5075 0 Blue 0
9 PM Sun 30 30 W 2 3294 5075 0 Blue 0
10 PM Sun 30 30 NW 2 3294 5075 0 Blue 0
11 PM Sun 30 30 NW 2 3294 5075 0 Blue 0
12 Midnight Mon 30 30 NW 2 3294 5075 0 Blue 0
1 AM Mon 30 30 N 2 3294 5075 0 Blue 0
2 AM Mon 30 30 N 2 3294 5075 0 Blue 0
3 AM Mon 29 29 N 2 3294 5075 0 Blue 0
4 AM Mon 29 29 NE 3 3294 5075 0 Blue 0
5 AM Mon 28 28 NE 3 3294 5075 0 Blue 0
6 AM Mon 27 27 NE 3 3294 5075 0 Blue 0
7 AM Mon 28 28 N 5 3294 5075 0 Blue 0
8 AM Mon 31 31 N 5 3294 5075 0 Blue 0
9 AM Mon 35 36 N 5 4834 5075 0 White 2
10 AM Mon 38 39 W 5 5492 5132 57 White 5
11 AM Mon 39 41 W 5 5929 5783 708 White 7
12 Noon Mon 39 41 W 5 5929 5783 708 White 7
1 PM Mon 39 41 W 5 5929 5783 708 White 7
2 PM Mon 39 40 W 5 5711 5459 384 White 6
3 PM Mon 38 39 W 3 5492 5132 57 White 5
4 PM Mon 37 37 W 3 5054 5075 0 White 3
5 PM Mon 35 35 NW 3 4611 5075 0 White 1
6 PM Mon 34 34 N 2 4213 5075 0 Blue 0
7 PM Mon 32 32 NE 2 3294 5075 0 Blue 0
8 PM Mon 31 31 NE 2 3294 5075 0 Blue 0
9 PM Mon 31 31 NE 3 3294 5075 0 Blue 0
10 PM Mon 31 31 NE 3 3294 5075 0 Blue 0
11 PM Mon 30 30 NE 3 3294 5075 0 Blue 0
12 Midnight Tue 30 30 NE 3 3294 5075 0 Blue 0
1 AM Tue 29 29 NE 3 3294 5075 0 Blue 0
2 AM Tue 29 29 NE 3 3294 5075 0 Blue 0
3 AM Tue 29 29 NE 5 3294 5075 0 Blue 0
4 AM Tue 29 29 NE 5 3294 5075 0 Blue 0
5 AM Tue 28 28 NE 5 3294 5075 0 Blue 0
6 AM Tue 27 27 NE 5 3294 5075 0 Blue 0
7 AM Tue 28 28 NE 5 3294 5075 0 Blue 0
8 AM Tue 32 32 E 5 3294 5075 0 Blue 0
9 AM Tue 36 37 S 3 5054 5075 0 White 3
10 AM Tue 40 42 SW 3 6146 6146 1071 White 8
11 AM Tue 42 45 W 3 6791 6791 1716 White 11
12 Noon Tue 42 45 NW 5 6791 6791 1716 White 11
1 PM Tue 42 45 NW 5 6791 6791 1716 White 11
2 PM Tue 42 44 NW 5 6577 6577 1502 White 10
3 PM Tue 41 42 NW 3 6146 6146 1071 White 8
4 PM Tue 40 40 NW 1 5711 5459 384 White 6
5 PM Tue 38 38 NW 1 5273 5075 0 White 4
6 PM Tue 35 35 NW 1 4611 5075 0 White 1
7 PM Tue 33 33 NW 1 3294 5075 0 Blue 0
8 PM Tue 32 32 NW 1 3294 5075 0 Blue 0
9 PM Tue 31 31 NW 1 3294 5075 0 Blue 0
10 PM Tue 31 31 NE 3 3294 5075 0 Blue 0
11 PM Tue 31 31 NE 3 3294 5075 0 Blue 0
12 Midnight Wed 30 30 NE 3 3294 5075 0 Blue 0
1 AM Wed 30 30 NE 3 3294 5075 0 Blue 0
2 AM Wed 30 30 NE 3 3294 5075 0 Blue 0
3 AM Wed 30 30 NE 3 3294 5075 0 Blue 0
4 AM Wed 30 30 NE 3 3294 5075 0 Blue 0
5 AM Wed 30 30 NE 3 3294 5075 0 Blue 0
6 AM Wed 30 30 NE 3 3294 5075 0 Blue 0
7 AM Wed 31 31 NE 3 3294 5075 0 Blue 0
8 AM Wed 34 34 NE 3 4213 5075 0 Blue 0
9 AM Wed 39 39 NE 3 5492 5132 57 White 5
10 AM Wed 42 43 SW 5 6361 6361 1286 White 9
11 AM Wed 44 46 SW 5 7005 7005 1930 White 12
12 Noon Wed 44 46 SW 5 7005 7005 1930 White 12
1 PM Wed 44 46 SW 5 7005 7005 1930 White 12
2 PM Wed 43 45 SW 5 6791 6791 1716 White 11
3 PM Wed 42 43 SW 5 6361 6361 1286 White 9
4 PM Wed 40 40 W 5 5711 5459 384 White 6
5 PM Wed 39 39 W 5 5492 5132 57 White 5
6 PM Wed 37 37 W 5 5054 5075 0 White 3
7 PM Wed 36 36 W 5 4834 5075 0 White 2
8 PM Wed 35 35 W 5 4611 5075 0 White 1
9 PM Wed 35 35 W 5 4611 5075 0 White 1
10 PM Wed 35 35 N 3 4611 5075 0 White 1
11 PM Wed 35 35 N 3 4611 5075 0 White 1
12 Midnight Thu 35 35 N 3 4611 5075 0 White 1
1 AM Thu 35 35 N 3 4611 5075 0 White 1
2 AM Thu 35 35 N 3 4611 5075 0 White 1
3 AM Thu 35 35 N 3 4611 5075 0 White 1
4 AM Thu 35 35 SW 1 4611 5075 0 White 1
5 AM Thu 34 34 SW 1 4213 5075 0 Blue 0
6 AM Thu 33 33 SW 1 3294 5075 0 Blue 0
7 AM Thu 33 33 SW 1 3294 5075 0 Blue 0
8 AM Thu 34 34 SW 1 4213 5075 0 Blue 0
9 AM Thu 36 36 SW 1 4834 5075 0 White 2
10 AM Thu 38 39 W 6 5492 5132 57 White 5
11 AM Thu 39 40 W 6 5711 5459 384 White 6
12 Noon Thu 40 41 W 6 5929 5783 708 White 7
1 PM Thu 40 41 W 6 5929 5783 708 White 7
2 PM Thu 39 40 W 6 5711 5459 384 White 6
3 PM Thu 38 38 W 6 5273 5075 0 White 4
4 PM Thu 36 36 W 3 4834 5075 0 White 2
5 PM Thu 35 35 W 3 4611 5075 0 White 1
6 PM Thu 34 34 W 3 4213 5075 0 Blue 0
7 PM Thu 33 33 W 3 3294 5075 0 Blue 0
8 PM Thu 33 33 W 3 3294 5075 0 Blue 0
9 PM Thu 32 32 W 3 3294 5075 0 Blue 0
10 PM Thu 32 32 E 3 3294 5075 0 Blue 0
11 PM Thu 32 32 E 3 3294 5075 0 Blue 0
12 Midnight Fri 31 31 E 3 3294 5075 0 Blue 0
1 AM Fri 31 31 E 3 3294 5075 0 Blue 0
2 AM Fri 31 31 E 3 3294 5075 0 Blue 0
3 AM Fri 31 31 E 3 3294 5075 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