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

Station:

 KVBG

Date/Time:

 4 FEB 2012

Temp/Wind data from:

NOAA Digital Forecast

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 40 40 E 9 2618 5075 0 Blue 0
5 AM Sat 40 40 E 9 2618 5075 0 Blue 0
6 AM Sat 40 40 E 9 2618 5075 0 Blue 0
7 AM Sat 40 40 E 8 2618 5075 0 Blue 0
8 AM Sat 41 41 E 8 2618 5075 0 Blue 0
9 AM Sat 43 44 E 8 2618 5075 0 Blue 0
10 AM Sat 45 47 SW 3 2618 5075 0 Blue 0
11 AM Sat 48 50 SW 3 4582 5075 0 Blue 0
12 Noon Sat 50 53 SW 3 6417 5075 0 Blue 3
1 PM Sat 52 54 W 6 6946 5280 205 Blue 4
2 PM Sat 54 56 W 6 7787 6371 1296 Blue 6
3 PM Sat 54 55 W 6 7460 5834 759 Blue 5
4 PM Sat 53 53 W 5 6417 5075 0 Blue 3
5 PM Sat 50 50 W 5 4582 5075 0 Blue 0
6 PM Sat 47 47 W 5 2618 5075 0 Blue 0
7 PM Sat 44 44 E 5 2618 5075 0 Blue 0
8 PM Sat 43 43 E 5 2618 5075 0 Blue 0
9 PM Sat 43 43 E 5 2618 5075 0 Blue 0
10 PM Sat 43 43 NE 7 2618 5075 0 Blue 0
11 PM Sat 43 43 NE 7 2618 5075 0 Blue 0
12 Midnight Sun 42 42 NE 7 2618 5075 0 Blue 0
1 AM Sun 42 42 NE 5 2618 5075 0 Blue 0
2 AM Sun 41 41 NE 5 2618 5075 0 Blue 0
3 AM Sun 40 40 NE 5 2618 5075 0 Blue 0
4 AM Sun 39 39 E 6 2618 5075 0 Blue 0
5 AM Sun 39 39 E 6 2618 5075 0 Blue 0
6 AM Sun 40 40 E 6 2618 5075 0 Blue 0
7 AM Sun 41 41 E 9 2618 5075 0 Blue 0
8 AM Sun 42 42 E 9 2618 5075 0 Blue 0
9 AM Sun 44 44 E 9 2618 5075 0 Blue 0
10 AM Sun 46 47 SW 3 2618 5075 0 Blue 0
11 AM Sun 49 51 SW 3 5308 5075 0 Blue 1
12 Noon Sun 52 54 SW 3 6946 5280 205 Blue 4
1 PM Sun 54 56 W 6 7787 6371 1296 Blue 6
2 PM Sun 54 55 W 6 7460 5834 759 Blue 5
3 PM Sun 54 55 W 6 7460 5834 759 Blue 5
4 PM Sun 52 52 W 5 5872 5075 0 Blue 2
5 PM Sun 50 50 W 5 4582 5075 0 Blue 0
6 PM Sun 48 48 W 5 2618 5075 0 Blue 0
7 PM Sun 46 46 E 5 2618 5075 0 Blue 0
8 PM Sun 45 45 E 5 2618 5075 0 Blue 0
9 PM Sun 44 44 E 5 2618 5075 0 Blue 0
10 PM Sun 44 44 E 6 2618 5075 0 Blue 0
11 PM Sun 44 44 E 6 2618 5075 0 Blue 0
12 Midnight Mon 44 44 E 6 2618 5075 0 Blue 0
1 AM Mon 44 44 NE 6 2618 5075 0 Blue 0
2 AM Mon 44 44 NE 6 2618 5075 0 Blue 0
3 AM Mon 43 43 NE 6 2618 5075 0 Blue 0
4 AM Mon 43 43 E 6 2618 5075 0 Blue 0
5 AM Mon 42 42 E 6 2618 5075 0 Blue 0
6 AM Mon 42 42 E 6 2618 5075 0 Blue 0
7 AM Mon 42 42 E 6 2618 5075 0 Blue 0
8 AM Mon 44 44 E 6 2618 5075 0 Blue 0
9 AM Mon 46 46 E 6 2618 5075 0 Blue 0
10 AM Mon 48 49 SW 5 3478 5075 0 Blue 0
11 AM Mon 51 53 SW 5 6417 5075 0 Blue 3
12 Noon Mon 53 55 SW 5 7460 5834 759 Blue 5
1 PM Mon 55 57 SW 5 7905 6893 1818 Blue 7
2 PM Mon 56 57 SW 5 7905 6893 1818 Blue 7
3 PM Mon 56 56 SW 5 7787 6371 1296 Blue 6
4 PM Mon 54 54 N 2 6946 5280 205 Blue 4
5 PM Mon 52 52 N 2 5872 5075 0 Blue 2
6 PM Mon 50 50 N 2 4582 5075 0 Blue 0
7 PM Mon 48 48 N 2 2618 5075 0 Blue 0
8 PM Mon 47 47 N 2 2618 5075 0 Blue 0
9 PM Mon 48 48 N 2 2618 5075 0 Blue 0
10 PM Mon 48 48 E 7 2618 5075 0 Blue 0
11 PM Mon 48 48 E 7 2618 5075 0 Blue 0
12 Midnight Tue 48 48 E 7 2618 5075 0 Blue 0
1 AM Tue 48 48 E 7 2618 5075 0 Blue 0
2 AM Tue 47 47 E 7 2618 5075 0 Blue 0
3 AM Tue 46 46 E 7 2618 5075 0 Blue 0
4 AM Tue 45 45 E 7 2618 5075 0 Blue 0
5 AM Tue 45 45 E 7 2618 5075 0 Blue 0
6 AM Tue 46 46 E 7 2618 5075 0 Blue 0
7 AM Tue 46 46 E 7 2618 5075 0 Blue 0
8 AM Tue 46 46 E 7 2618 5075 0 Blue 0
9 AM Tue 47 47 E 7 2618 5075 0 Blue 0
10 AM Tue 48 48 S 7 2618 5075 0 Blue 0
11 AM Tue 49 49 S 7 3478 5075 0 Blue 0
12 Noon Tue 51 51 S 7 5308 5075 0 Blue 1
1 PM Tue 52 52 S 7 5872 5075 0 Blue 2
2 PM Tue 52 52 S 7 5872 5075 0 Blue 2
3 PM Tue 51 51 S 7 5308 5075 0 Blue 1
4 PM Tue 50 50 S 3 4582 5075 0 Blue 0
5 PM Tue 49 49 S 3 3478 5075 0 Blue 0
6 PM Tue 47 47 S 3 2618 5075 0 Blue 0
7 PM Tue 46 46 S 3 2618 5075 0 Blue 0
8 PM Tue 46 46 S 3 2618 5075 0 Blue 0
9 PM Tue 45 45 S 3 2618 5075 0 Blue 0
10 PM Tue 45 45 E 3 2618 5075 0 Blue 0
11 PM Tue 45 45 E 3 2618 5075 0 Blue 0
12 Midnight Wed 45 45 E 3 2618 5075 0 Blue 0
1 AM Wed 45 45 E 3 2618 5075 0 Blue 0
2 AM Wed 45 45 E 3 2618 5075 0 Blue 0
3 AM Wed 45 45 E 3 2618 5075 0 Blue 0
4 AM Wed 45 45 E 1 2618 5075 0 Blue 0
5 AM Wed 44 44 E 1 2618 5075 0 Blue 0
6 AM Wed 44 44 E 1 2618 5075 0 Blue 0
7 AM Wed 44 44 E 1 2618 5075 0 Blue 0
8 AM Wed 44 44 E 1 2618 5075 0 Blue 0
9 AM Wed 44 44 E 1 2618 5075 0 Blue 0
10 AM Wed 44 45 W 2 2618 5075 0 Blue 0
11 AM Wed 45 46 W 2 2618 5075 0 Blue 0
12 Noon Wed 47 48 W 2 2618 5075 0 Blue 0
1 PM Wed 48 49 W 2 3478 5075 0 Blue 0
2 PM Wed 48 49 W 2 3478 5075 0 Blue 0
3 PM Wed 48 48 W 2 2618 5075 0 Blue 0
4 PM Wed 47 47 W 6 2618 5075 0 Blue 0
5 PM Wed 46 46 W 6 2618 5075 0 Blue 0
6 PM Wed 45 45 W 6 2618 5075 0 Blue 0
7 PM Wed 43 43 W 6 2618 5075 0 Blue 0
8 PM Wed 42 42 W 6 2618 5075 0 Blue 0
9 PM Wed 42 42 W 6 2618 5075 0 Blue 0
10 PM Wed 42 42 E 12 2618 5075 0 Blue 0
11 PM Wed 42 42 E 12 2618 5075 0 Blue 0
12 Midnight Thu 42 42 E 12 2618 5075 0 Blue 0
1 AM Thu 42 42 E 12 2618 5075 0 Blue 0
2 AM Thu 41 41 E 12 2618 5075 0 Blue 0
3 AM Thu 40 40 E 12 2618 5075 0 Blue 0
4 AM Thu 39 39 E 12 2618 5075 0 Blue 0
5 AM Thu 39 39 E 12 2618 5075 0 Blue 0
6 AM Thu 39 39 E 12 2618 5075 0 Blue 0
7 AM Thu 40 40 E 12 2618 5075 0 Blue 0
8 AM Thu 41 41 E 12 2618 5075 0 Blue 0
9 AM Thu 43 44 E 12 2618 5075 0 Blue 0
10 AM Thu 46 48 SW 3 2618 5075 0 Blue 0
11 AM Thu 48 50 SW 3 4582 5075 0 Blue 0
12 Noon Thu 51 54 SW 3 6946 5280 205 Blue 4
1 PM Thu 52 54 SW 3 6946 5280 205 Blue 4
2 PM Thu 53 55 SW 3 7460 5834 759 Blue 5
3 PM Thu 53 54 SW 3 6946 5280 205 Blue 4
4 PM Thu 51 51 W 5 5308 5075 0 Blue 1
5 PM Thu 49 49 W 5 3478 5075 0 Blue 0
6 PM Thu 47 47 W 5 2618 5075 0 Blue 0
7 PM Thu 45 45 W 5 2618 5075 0 Blue 0
8 PM Thu 45 45 W 5 2618 5075 0 Blue 0
9 PM Thu 45 45 W 5 2618 5075 0 Blue 0
10 PM Thu 45 45 E 8 2618 5075 0 Blue 0
11 PM Thu 44 44 E 8 2618 5075 0 Blue 0
12 Midnight Fri 43 43 E 8 2618 5075 0 Blue 0
1 AM Fri 43 43 E 8 2618 5075 0 Blue 0
2 AM Fri 42 42 E 8 2618 5075 0 Blue 0
3 AM Fri 42 42 E 8 2618 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