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

Station:

KVBG

Date/Time:

24 AUG 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 Sat 72 72 E 3 3579 5075 0 Blue 0
6 AM Sat 70 70 E 3 3579 5075 0 Blue 0
7 AM Sat 70 70 E 3 3579 5075 0 Blue 0
8 AM Sat 77 77 E 2 4781 5075 0 Blue 3
9 AM Sat 81 83 SW 2 7871 6046 971 Blue 9
10 AM Sat 83 87 SW 6 8417 7963 2888 Blue 13
11 AM Sat 85 91 SW 6 9426 8592 3517 Blue 17
12 Noon Sat 88 95 W 6 10770 9665 4590 Blue 21
1 PM Sat 89 97 W 6 11572 10243 5168 Blue 23
2 PM Sat 91 98 W 6 11744 10665 5590 Blue 24
3 PM Sat 92 98 W 6 11744 10665 5590 Blue 24
4 PM Sat 91 95 W 6 10770 9665 4590 Blue 21
5 PM Sat 90 92 W 6 9720 8784 3709 Blue 18
6 PM Sat 88 89 W 5 8831 8182 3107 Blue 15
7 PM Sat 82 82 W 3 7761 5576 501 Blue 8
8 PM Sat 75 75 NW 2 4368 5075 0 Blue 1
9 PM Sat 75 75 NE 2 4368 5075 0 Blue 1
10 PM Sat 74 74 E 2 4116 5075 0 Blue 0
11 PM Sat 73 73 S 2 3592 5075 0 Blue 0
12 Midnight Sun 74 74 E 2 4116 5075 0 Blue 0
1 AM Sun 73 73 E 2 3592 5075 0 Blue 0
2 AM Sun 73 73 E 3 3592 5075 0 Blue 0
3 AM Sun 73 73 NE 3 3592 5075 0 Blue 0
4 AM Sun 74 74 E 3 4116 5075 0 Blue 0
5 AM Sun 73 73 NE 3 3592 5075 0 Blue 0
6 AM Sun 71 71 E 3 3579 5075 0 Blue 0
7 AM Sun 71 71 E 3 3579 5075 0 Blue 0
8 AM Sun 78 78 W 2 5116 5075 0 Blue 4
9 AM Sun 82 84 W 2 7977 7192 2117 Blue 10
10 AM Sun 84 88 W 6 8623 8070 2995 Blue 14
11 AM Sun 86 92 W 6 9720 8784 3709 Blue 18
12 Noon Sun 88 95 W 6 10770 9665 4590 Blue 21
1 PM Sun 90 98 W 6 11744 10665 5590 Blue 24
2 PM Sun 91 97 W 7 11572 10243 5168 Blue 23
3 PM Sun 92 97 W 7 11572 10243 5168 Blue 23
4 PM Sun 92 95 W 7 10770 9665 4590 Blue 21
5 PM Sun 90 92 W 6 9720 8784 3709 Blue 18
6 PM Sun 85 86 W 6 8211 7857 2782 Blue 12
7 PM Sun 80 80 W 6 6079 5075 0 Blue 6
8 PM Sun 75 75 NW 2 4368 5075 0 Blue 1
9 PM Sun 74 74 NW 2 4116 5075 0 Blue 0
10 PM Sun 73 73 NW 2 3592 5075 0 Blue 0
11 PM Sun 74 74 NW 3 4116 5075 0 Blue 0
12 Midnight Mon 74 74 NW 3 4116 5075 0 Blue 0
1 AM Mon 74 74 NW 3 4116 5075 0 Blue 0
2 AM Mon 74 74 NE 3 4116 5075 0 Blue 0
3 AM Mon 74 74 NE 3 4116 5075 0 Blue 0
4 AM Mon 74 74 NE 3 4116 5075 0 Blue 0
5 AM Mon 74 74 NE 3 4116 5075 0 Blue 0
6 AM Mon 75 75 NE 3 4368 5075 0 Blue 1
7 AM Mon 77 77 NE 3 4781 5075 0 Blue 3
8 AM Mon 79 79 NW 2 5603 5075 0 Blue 5
9 AM Mon 81 83 NW 2 7871 6046 971 Blue 9
10 AM Mon 84 87 NW 2 8417 7963 2888 Blue 13
11 AM Mon 86 90 SW 6 9129 8387 3312 Blue 16
12 Noon Mon 88 93 SW 6 10012 9080 4005 Blue 19
1 PM Mon 91 96 SW 6 11245 9955 4880 Blue 22
2 PM Mon 92 96 W 6 11245 9955 4880 Blue 22
3 PM Mon 93 96 W 6 11245 9955 4880 Blue 22
4 PM Mon 93 95 W 6 10770 9665 4590 Blue 21
5 PM Mon 91 92 W 6 9720 8784 3709 Blue 18
6 PM Mon 86 86 W 6 8211 7857 2782 Blue 12
7 PM Mon 81 81 W 6 7401 5096 21 Blue 7
8 PM Mon 76 76 W 2 4575 5075 0 Blue 2
9 PM Mon 75 75 W 2 4368 5075 0 Blue 1
10 PM Mon 74 74 W 2 4116 5075 0 Blue 0
11 PM Mon 75 75 NE 2 4368 5075 0 Blue 1
12 Midnight Tue 75 75 NE 2 4368 5075 0 Blue 1
1 AM Tue 75 75 NE 2 4368 5075 0 Blue 1
2 AM Tue 75 75 E 3 4368 5075 0 Blue 1
3 AM Tue 74 74 E 3 4116 5075 0 Blue 0
4 AM Tue 74 74 E 3 4116 5075 0 Blue 0
5 AM Tue 74 74 E 5 4116 5075 0 Blue 0
6 AM Tue 75 75 E 5 4368 5075 0 Blue 1
7 AM Tue 77 77 E 5 4781 5075 0 Blue 3
8 AM Tue 80 80 E 2 6079 5075 0 Blue 6
9 AM Tue 83 85 E 2 8084 7739 2664 Blue 11
10 AM Tue 85 89 E 2 8831 8182 3107 Blue 15
11 AM Tue 88 93 W 6 10012 9080 4005 Blue 19
12 Noon Tue 91 98 W 6 11744 10665 5590 Blue 24
1 PM Tue 93 100 W 6 12088 11529 6454 Blue 26
2 PM Tue 94 101 W 6 12259 11700 6625 Blue 27
3 PM Tue 95 101 W 6 12259 11700 6625 Blue 27
4 PM Tue 95 99 W 6 11916 11134 6059 Blue 25
5 PM Tue 93 95 W 5 10770 9665 4590 Blue 21
6 PM Tue 88 88 W 5 8623 8070 2995 Blue 14
7 PM Tue 83 83 W 5 7871 6046 971 Blue 9
8 PM Tue 78 78 W 2 5116 5075 0 Blue 4
9 PM Tue 76 76 W 2 4575 5075 0 Blue 2
10 PM Tue 76 76 W 2 4575 5075 0 Blue 2
11 PM Tue 76 76 E 3 4575 5075 0 Blue 2
12 Midnight Wed 76 76 E 3 4575 5075 0 Blue 2
1 AM Wed 76 76 E 3 4575 5075 0 Blue 2
2 AM Wed 76 76 NE 3 4575 5075 0 Blue 2
3 AM Wed 75 75 NE 3 4368 5075 0 Blue 1
4 AM Wed 75 75 NE 3 4368 5075 0 Blue 1
5 AM Wed 75 75 E 3 4368 5075 0 Blue 1
6 AM Wed 76 76 E 3 4575 5075 0 Blue 2
7 AM Wed 79 79 E 3 5603 5075 0 Blue 5
8 AM Wed 81 81 E 2 7401 5096 21 Blue 7
9 AM Wed 83 85 E 2 8084 7739 2664 Blue 11
10 AM Wed 86 90 E 2 9129 8387 3312 Blue 16
11 AM Wed 88 93 SW 6 10012 9080 4005 Blue 19
12 Noon Wed 90 96 SW 6 11245 9955 4880 Blue 22
1 PM Wed 92 99 SW 6 11916 11134 6059 Blue 25
2 PM Wed 93 99 W 6 11916 11134 6059 Blue 25
3 PM Wed 94 99 W 6 11916 11134 6059 Blue 25
4 PM Wed 94 98 W 6 11744 10665 5590 Blue 24
5 PM Wed 92 94 W 6 10302 9373 4298 Blue 20
6 PM Wed 87 87 W 6 8417 7963 2888 Blue 13
7 PM Wed 81 81 W 6 7401 5096 21 Blue 7
8 PM Wed 76 76 N 2 4575 5075 0 Blue 2
9 PM Wed 74 74 N 2 4116 5075 0 Blue 0
10 PM Wed 74 74 N 2 4116 5075 0 Blue 0
11 PM Wed 74 74 W 2 4116 5075 0 Blue 0
12 Midnight Thu 74 74 W 2 4116 5075 0 Blue 0
1 AM Thu 74 74 W 2 4116 5075 0 Blue 0
2 AM Thu 74 74 E 3 4116 5075 0 Blue 0
3 AM Thu 73 73 E 3 3592 5075 0 Blue 0
4 AM Thu 73 73 E 3 3592 5075 0 Blue 0
5 AM Thu 73 73 E 3 3592 5075 0 Blue 0
6 AM Thu 74 74 E 3 4116 5075 0 Blue 0
7 AM Thu 75 75 E 3 4368 5075 0 Blue 1
8 AM Thu 77 77 S 2 4781 5075 0 Blue 3
9 AM Thu 80 82 S 2 7761 5576 501 Blue 8
10 AM Thu 82 86 S 2 8211 7857 2782 Blue 12
11 AM Thu 85 89 W 6 8831 8182 3107 Blue 15
12 Noon Thu 87 92 W 6 9720 8784 3709 Blue 18
1 PM Thu 89 95 W 6 10770 9665 4590 Blue 21
2 PM Thu 90 95 W 6 10770 9665 4590 Blue 21
3 PM Thu 91 95 W 6 10770 9665 4590 Blue 21
4 PM Thu 91 94 W 6 10302 9373 4298 Blue 20
5 PM Thu 89 91 W 6 9426 8592 3517 Blue 17
6 PM Thu 84 84 W 6 7977 7192 2117 Blue 10
7 PM Thu 79 79 W 6 5603 5075 0 Blue 5
8 PM Thu 74 74 W 2 4116 5075 0 Blue 0
9 PM Thu 73 73 W 2 3592 5075 0 Blue 0
10 PM Thu 72 72 W 2 3579 5075 0 Blue 0
11 PM Thu 73 73 E 2 3592 5075 0 Blue 0
12 Midnight Fri 73 73 E 2 3592 5075 0 Blue 0
1 AM Fri 73 73 E 2 3592 5075 0 Blue 0
2 AM Fri 73 73 E 3 3592 5075 0 Blue 0
3 AM Fri 72 72 E 3 3579 5075 0 Blue 0
4 AM Fri 72 72 E 3 3579 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