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

Station:

 KVBG

Date/Time:

 11 MAR 2010

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)
7 AM Thu 31 31 NE 5 2667 5075 0 Blue 0
8 AM Thu 34 35 NE 5 2667 5075 0 Blue 0
9 AM Thu 32 34 NE 5 2667 5075 0 Blue 0
10 AM Thu 46 50 SE 5 4839 5075 0 Blue 6
11 AM Thu 47 52 SE 5 5200 5075 0 Blue 8
12 Noon Thu 45 50 SE 5 4839 5075 0 Blue 6
1 PM Thu 46 51 S 7 4993 5075 0 Blue 7
2 PM Thu 45 49 S 7 4759 5075 0 Blue 5
3 PM Thu 54 56 S 7 6253 5451 376 Blue 12
4 PM Thu 46 47 SE 4 4683 5075 0 Blue 3
5 PM Thu 46 46 SE 4 4651 5075 0 Blue 2
6 PM Thu 49 49 SE 4 4759 5075 0 Blue 5
7 PM Thu 52 52 E 6 5200 5075 0 Blue 8
8 PM Thu 51 51 E 6 4993 5075 0 Blue 7
9 PM Thu 47 47 E 6 4683 5075 0 Blue 3
10 PM Thu 46 46 E 7 4651 5075 0 Blue 2
11 PM Thu 44 44 E 7 4587 5075 0 Blue 0
12 Midnight Fri 41 41 E 7 3417 5075 0 Blue 0
1 AM Fri 46 46 E 7 4651 5075 0 Blue 2
2 AM Fri 45 45 E 7 4619 5075 0 Blue 1
3 AM Fri 44 44 E 7 4587 5075 0 Blue 0
4 AM Fri 43 43 E 6 4234 5075 0 Blue 0
5 AM Fri 43 43 E 6 4234 5075 0 Blue 0
6 AM Fri 37 37 E 6 2667 5075 0 Blue 0
7 AM Fri 36 36 E 6 2667 5075 0 Blue 0
8 AM Fri 39 39 E 6 2667 5075 0 Blue 0
9 AM Fri 37 38 E 6 2667 5075 0 Blue 0
10 AM Fri 52 54 SW 6 5729 5075 0 Blue 10
11 AM Fri 53 55 SW 6 5991 5188 113 Blue 11
12 Noon Fri 51 54 SW 6 5729 5075 0 Blue 10
1 PM Fri 51 53 SW 6 5465 5075 0 Blue 9
2 PM Fri 50 52 SW 6 5200 5075 0 Blue 8
3 PM Fri 60 61 SW 6 7579 6745 1670 Blue 17
4 PM Fri 52 52 SW 7 5200 5075 0 Blue 8
5 PM Fri 51 51 SW 7 4993 5075 0 Blue 7
6 PM Fri 54 54 SW 7 5729 5075 0 Blue 10
7 PM Fri 57 57 SW 7 6512 5712 637 Blue 13
8 PM Fri 57 57 SW 7 6512 5712 637 Blue 13
9 PM Fri 52 52 SW 7 5200 5075 0 Blue 8
10 PM Fri 51 51 SW 6 4993 5075 0 Blue 7
11 PM Fri 49 49 SW 6 4759 5075 0 Blue 5
12 Midnight Sat 45 45 SW 6 4619 5075 0 Blue 1
1 AM Sat 51 51 SW 6 4993 5075 0 Blue 7
2 AM Sat 50 50 SW 6 4839 5075 0 Blue 6
3 AM Sat 49 49 SW 6 4759 5075 0 Blue 5
4 AM Sat 47 47 W 6 4683 5075 0 Blue 3
5 AM Sat 48 48 W 6 4715 5075 0 Blue 4
6 AM Sat 41 41 W 6 3417 5075 0 Blue 0
7 AM Sat 40 40 W 6 2998 5075 0 Blue 0
8 AM Sat 41 41 W 6 3417 5075 0 Blue 0
9 AM Sat 40 41 W 6 3417 5075 0 Blue 0
10 AM Sat 45 46 NW 8 4651 5075 0 Blue 2
11 AM Sat 46 48 NW 8 4715 5075 0 Blue 4
12 Noon Sat 45 47 NW 8 4683 5075 0 Blue 3
1 PM Sat 45 47 NW 8 4683 5075 0 Blue 3
2 PM Sat 45 46 NW 8 4651 5075 0 Blue 2
3 PM Sat 48 49 NW 8 4759 5075 0 Blue 5
4 PM Sat 42 42 NW 8 3829 5075 0 Blue 0
5 PM Sat 41 41 NW 8 3417 5075 0 Blue 0
6 PM Sat 44 44 NW 8 4587 5075 0 Blue 0
7 PM Sat 46 46 NW 8 4651 5075 0 Blue 2
8 PM Sat 46 46 NW 8 4651 5075 0 Blue 2
9 PM Sat 43 43 NW 8 4234 5075 0 Blue 0
10 PM Sat 42 42 E 2 3829 5075 0 Blue 0
11 PM Sat 40 40 E 2 2998 5075 0 Blue 0
12 Midnight Sun 38 38 E 2 2667 5075 0 Blue 0
1 AM Sun 42 42 E 2 3829 5075 0 Blue 0
2 AM Sun 41 41 E 2 3417 5075 0 Blue 0
3 AM Sun 41 41 E 2 3417 5075 0 Blue 0
4 AM Sun 39 39 E 2 2667 5075 0 Blue 0
5 AM Sun 39 39 E 2 2667 5075 0 Blue 0
6 AM Sun 34 34 E 2 2667 5075 0 Blue 0
7 AM Sun 34 34 E 2 2667 5075 0 Blue 0
8 AM Sun 37 38 E 2 2667 5075 0 Blue 0
9 AM Sun 35 37 E 2 2667 5075 0 Blue 0
10 AM Sun 49 52 SW 4 5200 5075 0 Blue 8
11 AM Sun 49 53 SW 4 5465 5075 0 Blue 9
12 Noon Sun 48 53 SW 4 5465 5075 0 Blue 9
1 PM Sun 48 52 SW 4 5200 5075 0 Blue 8
2 PM Sun 47 50 SW 4 4839 5075 0 Blue 6
3 PM Sun 56 58 SW 4 6771 5973 898 Blue 14
4 PM Sun 50 51 W 3 4993 5075 0 Blue 7
5 PM Sun 49 49 W 3 4759 5075 0 Blue 5
6 PM Sun 52 52 W 3 5200 5075 0 Blue 8
7 PM Sun 54 54 W 3 5729 5075 0 Blue 10
8 PM Sun 54 54 W 3 5729 5075 0 Blue 10
9 PM Sun 50 50 W 3 4839 5075 0 Blue 6
10 PM Sun 49 49 E 4 4759 5075 0 Blue 5
11 PM Sun 48 48 E 4 4715 5075 0 Blue 4
12 Midnight Mon 45 45 E 4 4619 5075 0 Blue 1
1 AM Mon 49 49 E 4 4759 5075 0 Blue 5
2 AM Mon 48 48 E 4 4715 5075 0 Blue 4
3 AM Mon 48 48 E 4 4715 5075 0 Blue 4
4 AM Mon 47 47 E 3 4683 5075 0 Blue 3
5 AM Mon 47 47 E 3 4683 5075 0 Blue 3
6 AM Mon 41 41 E 3 3417 5075 0 Blue 0
7 AM Mon 41 41 E 3 3417 5075 0 Blue 0
8 AM Mon 44 45 E 3 4619 5075 0 Blue 1
9 AM Mon 42 44 E 3 4587 5075 0 Blue 0
10 AM Mon 58 62 W 3 7910 7001 1926 Blue 18
11 AM Mon 59 64 W 3 8563 7538 2463 Blue 20
12 Noon Mon 56 61 W 3 7579 6745 1670 Blue 17
1 PM Mon 57 62 W 3 7910 7001 1926 Blue 18
2 PM Mon 56 60 W 3 7284 6489 1414 Blue 16
3 PM Mon 66 68 W 3 10019 8830 3755 Blue 24
4 PM Mon 57 58 W 2 6771 5973 898 Blue 14
5 PM Mon 56 56 W 2 6253 5451 376 Blue 12
6 PM Mon 60 60 W 2 7284 6489 1414 Blue 16
7 PM Mon 63 63 W 2 8238 7254 2179 Blue 19
8 PM Mon 62 62 W 2 7910 7001 1926 Blue 18
9 PM Mon 58 58 W 2 6771 5973 898 Blue 14
10 PM Mon 56 56 E 11 6253 5451 376 Blue 12
11 PM Mon 54 54 E 11 5729 5075 0 Blue 10
12 Midnight Tue 50 50 E 11 4839 5075 0 Blue 6
1 AM Tue 56 56 E 11 6253 5451 376 Blue 12
2 AM Tue 54 54 E 11 5729 5075 0 Blue 10
3 AM Tue 54 54 E 11 5729 5075 0 Blue 10
4 AM Tue 52 52 E 10 5200 5075 0 Blue 8
5 AM Tue 53 53 E 10 5465 5075 0 Blue 9
6 AM Tue 45 45 E 10 4619 5075 0 Blue 1
7 AM Tue 44 44 E 10 4587 5075 0 Blue 0
8 AM Tue 47 48 E 10 4715 5075 0 Blue 4
9 AM Tue 45 47 E 10 4683 5075 0 Blue 3
10 AM Tue 59 62 SW 2 7910 7001 1926 Blue 18
11 AM Tue 59 63 SW 2 8238 7254 2179 Blue 19
12 Noon Tue 58 63 SW 2 8238 7254 2179 Blue 19
1 PM Tue 58 62 SW 2 7910 7001 1926 Blue 18
2 PM Tue 57 60 SW 2 7284 6489 1414 Blue 16
3 PM Tue 66 68 SW 2 10019 8830 3755 Blue 24
4 PM Tue 56 57 W 4 6512 5712 637 Blue 13
5 PM Tue 55 55 W 4 5991 5188 113 Blue 11
6 PM Tue 59 59 W 4 7028 6232 1157 Blue 15
7 PM Tue 63 63 W 4 8238 7254 2179 Blue 19
8 PM Tue 62 62 W 4 7910 7001 1926 Blue 18
9 PM Tue 57 57 W 4 6512 5712 637 Blue 13
10 PM Tue 56 56 E 3 6253 5451 376 Blue 12
11 PM Tue 54 54 E 3 5729 5075 0 Blue 10
12 Midnight Wed 49 49 E 3 4759 5075 0 Blue 5
1 AM Wed 56 56 E 3 6253 5451 376 Blue 12
2 AM Wed 54 54 E 3 5729 5075 0 Blue 10
3 AM Wed 54 54 E 3 5729 5075 0 Blue 10
4 AM Wed 52 52 E 2 5200 5075 0 Blue 8
5 AM Wed 52 52 E 2 5200 5075 0 Blue 8
6 AM Wed 44 44 E 2 4587 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