Detailed Predictions for: Whetstone Mountain
Launch Altitude (f): 5900
LZ Altitude (f): 5500
Sounding

Station:

KTUS

Date/Time:

27 MAY 2018

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)
6 AM Sun 50 50 W 7 5285 5900 0 Blue 0
7 AM Sun 51 52 SW 6 5285 5900 0 Blue 0
8 AM Sun 61 63 S 6 7753 6804 904 Blue 4
9 AM Sun 65 69 SE 6 9651 8738 2838 Blue 10
10 AM Sun 68 74 S 7 10738 10044 4144 Blue 15
11 AM Sun 72 79 S 8 13585 11731 5831 Blue 20
12 Noon Sun 75 83 SW 9 16059 13989 8089 Blue 24
1 PM Sun 77 85 SW 12 18158 15010 9110 Blue 26
2 PM Sun 79 85 SW 14 18158 15010 9110 Blue 26
3 PM Sun 80 85 W 16 18158 15010 9110 Blue 26
4 PM Sun 80 83 W 17 16059 13989 8089 Blue 24
5 PM Sun 79 80 W 17 14125 12328 6428 Blue 21
6 PM Sun 78 78 W 17 13026 11108 5208 Blue 19
7 PM Sun 76 76 W 17 11842 10483 4583 Blue 17
8 PM Sun 70 70 W 16 9861 9052 3152 Blue 11
9 PM Sun 65 65 W 15 8444 7381 1481 Blue 6
10 PM Sun 63 63 W 14 7753 6804 904 Blue 4
11 PM Sun 61 61 W 14 7069 6074 174 Blue 2
12 Midnight Mon 59 59 W 13 6547 5900 0 Blue 0
1 AM Mon 57 57 W 13 5485 5900 0 Blue 0
2 AM Mon 56 56 W 12 5285 5900 0 Blue 0
3 AM Mon 55 55 NW 12 5285 5900 0 Blue 0
4 AM Mon 54 54 NW 9 5285 5900 0 Blue 0
5 AM Mon 54 54 NW 8 5285 5900 0 Blue 0
6 AM Mon 53 53 NW 8 5285 5900 0 Blue 0
7 AM Mon 54 55 NW 7 5285 5900 0 Blue 0
8 AM Mon 63 65 N 7 8444 7381 1481 Blue 6
9 AM Mon 68 72 NE 7 10288 9628 3728 Blue 13
10 AM Mon 71 77 N 6 12446 10706 4806 Blue 18
11 AM Mon 74 81 NW 6 14648 12901 7001 Blue 22
12 Noon Mon 78 86 W 6 18494 15574 9674 Blue 27
1 PM Mon 80 88 W 8 19207 18022 12122 Blue 29
2 PM Mon 81 87 W 10 18827 16926 11026 Blue 28
3 PM Mon 82 87 W 13 18827 16926 11026 Blue 28
4 PM Mon 83 86 W 14 18494 15574 9674 Blue 27
5 PM Mon 82 83 W 15 16059 13989 8089 Blue 24
6 PM Mon 81 81 W 16 14648 12901 7001 Blue 22
7 PM Mon 79 79 W 16 13585 11731 5831 Blue 20
8 PM Mon 73 73 W 15 10514 9837 3937 Blue 14
9 PM Mon 68 68 NW 14 9396 8421 2521 Blue 9
10 PM Mon 66 66 NW 14 8764 7736 1836 Blue 7
11 PM Mon 65 65 W 13 8444 7381 1481 Blue 6
12 Midnight Tue 63 63 W 12 7753 6804 904 Blue 4
1 AM Tue 61 61 NW 10 7069 6074 174 Blue 2
2 AM Tue 60 60 NW 9 6809 5900 0 Blue 1
3 AM Tue 59 59 NW 9 6547 5900 0 Blue 0
4 AM Tue 58 58 NW 8 6072 5900 0 Blue 0
5 AM Tue 58 58 NW 8 6072 5900 0 Blue 0
6 AM Tue 56 56 NW 8 5285 5900 0 Blue 0
7 AM Tue 57 57 NW 7 5485 5900 0 Blue 0
8 AM Tue 67 69 N 6 9651 8738 2838 Blue 10
9 AM Tue 71 75 N 6 11211 10259 4359 Blue 16
10 AM Tue 74 79 N 5 13585 11731 5831 Blue 20
11 AM Tue 77 83 NE 5 16059 13989 8089 Blue 24
12 Noon Tue 80 87 NE 5 18827 16926 11026 Blue 28
1 PM Tue 82 89 N 6 19702 18356 12456 Blue 30
2 PM Tue 84 90 N 8 20183 18686 12786 Blue 31
3 PM Tue 85 90 NW 10 20183 18686 12786 Blue 31
4 PM Tue 85 88 NW 12 19207 18022 12122 Blue 29
5 PM Tue 84 85 W 14 18158 15010 9110 Blue 26
6 PM Tue 83 83 W 15 16059 13989 8089 Blue 24
7 PM Tue 81 81 W 15 14648 12901 7001 Blue 22
8 PM Tue 76 76 W 15 11842 10483 4583 Blue 17
9 PM Tue 70 70 W 14 9861 9052 3152 Blue 11
10 PM Tue 68 68 W 13 9396 8421 2521 Blue 9
11 PM Tue 67 67 W 12 9081 8086 2186 Blue 8
12 Midnight Wed 64 64 W 12 8108 7062 1162 Blue 5
1 AM Wed 63 63 W 10 7753 6804 904 Blue 4
2 AM Wed 62 62 SW 10 7395 6544 644 Blue 3
3 AM Wed 60 60 SW 9 6809 5900 0 Blue 1
4 AM Wed 60 60 SW 9 6809 5900 0 Blue 1
5 AM Wed 60 60 SW 9 6809 5900 0 Blue 1
6 AM Wed 58 58 SW 9 6072 5900 0 Blue 0
7 AM Wed 59 60 SW 9 6809 5900 0 Blue 1
8 AM Wed 68 70 SW 10 9861 9052 3152 Blue 11
9 AM Wed 72 76 SW 10 11842 10483 4583 Blue 17
10 AM Wed 75 81 SW 12 14648 12901 7001 Blue 22
11 AM Wed 78 86 SW 13 18494 15574 9674 Blue 27
12 Noon Wed 81 90 SW 14 20183 18686 12786 Blue 31
1 PM Wed 83 91 SW 15 22300 19013 13113 White 32
2 PM Wed 84 91 SW 16 22300 19013 13113 White 32
3 PM Wed 86 91 SW 17 22300 19013 13113 White 32
4 PM Wed 86 89 SW 18 19702 18356 12456 Blue 30
5 PM Wed 85 86 SW 18 18494 15574 9674 Blue 27
6 PM Wed 84 84 SW 18 17360 14507 8607 Blue 25
7 PM Wed 81 81 SW 18 14648 12901 7001 Blue 22
8 PM Wed 75 75 SW 17 11211 10259 4359 Blue 16
9 PM Wed 70 70 SW 16 9861 9052 3152 Blue 11
10 PM Wed 67 67 SW 15 9081 8086 2186 Blue 8
11 PM Wed 66 66 SW 14 8764 7736 1836 Blue 7
12 Midnight Thu 63 63 SW 13 7753 6804 904 Blue 4
1 AM Thu 61 61 SW 13 7069 6074 174 Blue 2
2 AM Thu 60 60 S 12 6809 5900 0 Blue 1
3 AM Thu 59 59 S 12 6547 5900 0 Blue 0
4 AM Thu 58 58 S 12 6072 5900 0 Blue 0
5 AM Thu 58 58 S 12 6072 5900 0 Blue 0
6 AM Thu 56 56 S 12 5285 5900 0 Blue 0
7 AM Thu 57 58 S 13 6072 5900 0 Blue 0
8 AM Thu 66 68 S 14 9396 8421 2521 Blue 9
9 AM Thu 70 74 S 15 10738 10044 4144 Blue 15
10 AM Thu 73 79 S 16 13585 11731 5831 Blue 20
11 AM Thu 76 83 SW 17 16059 13989 8089 Blue 24
12 Noon Thu 80 88 SW 18 19207 18022 12122 Blue 29
1 PM Thu 82 90 SW 20 20183 18686 12786 Blue 31
2 PM Thu 83 90 SW 20 20183 18686 12786 Blue 31
3 PM Thu 84 89 SW 21 19702 18356 12456 Blue 30
4 PM Thu 85 88 SW 22 19207 18022 12122 Blue 29
5 PM Thu 84 85 SW 22 18158 15010 9110 Blue 26
6 PM Thu 83 83 SW 21 16059 13989 8089 Blue 24
7 PM Thu 80 80 SW 21 14125 12328 6428 Blue 21
8 PM Thu 74 74 SW 18 10738 10044 4144 Blue 15
9 PM Thu 69 69 SW 17 9651 8738 2838 Blue 10
10 PM Thu 66 66 SW 15 8764 7736 1836 Blue 7
11 PM Thu 64 64 SW 14 8108 7062 1162 Blue 5
12 Midnight Fri 62 62 SW 13 7395 6544 644 Blue 3
1 AM Fri 60 60 SW 12 6809 5900 0 Blue 1
2 AM Fri 59 59 SW 12 6547 5900 0 Blue 0
3 AM Fri 58 58 SW 10 6072 5900 0 Blue 0
4 AM Fri 57 57 S 10 5485 5900 0 Blue 0
5 AM Fri 57 57 S 12 5485 5900 0 Blue 0
6 AM Fri 55 55 S 12 5285 5900 0 Blue 0
7 AM Fri 56 57 S 12 5485 5900 0 Blue 0
8 AM Fri 66 68 S 13 9396 8421 2521 Blue 9
9 AM Fri 70 74 SW 14 10738 10044 4144 Blue 15
10 AM Fri 73 79 SW 15 13585 11731 5831 Blue 20
11 AM Fri 76 84 SW 15 17360 14507 8607 Blue 25
12 Noon Fri 80 88 SW 16 19207 18022 12122 Blue 29
1 PM Fri 82 90 SW 17 20183 18686 12786 Blue 31
2 PM Fri 83 90 SW 17 20183 18686 12786 Blue 31
3 PM Fri 85 90 SW 18 20183 18686 12786 Blue 31
4 PM Fri 85 88 W 18 19207 18022 12122 Blue 29
5 PM Fri 84 85 W 18 18158 15010 9110 Blue 26
6 PM Fri 83 83 W 18 16059 13989 8089 Blue 24
7 PM Fri 80 80 W 17 14125 12328 6428 Blue 21
8 PM Fri 74 74 W 16 10738 10044 4144 Blue 15
9 PM Fri 69 69 W 14 9651 8738 2838 Blue 10
10 PM Fri 66 66 W 13 8764 7736 1836 Blue 7
11 PM Fri 65 65 W 10 8444 7381 1481 Blue 6
12 Midnight Sat 62 62 W 9 7395 6544 644 Blue 3
1 AM Sat 60 60 SW 9 6809 5900 0 Blue 1
2 AM Sat 59 59 S 8 6547 5900 0 Blue 0
3 AM Sat 58 58 S 8 6072 5900 0 Blue 0
4 AM Sat 57 57 SE 7 5485 5900 0 Blue 0
5 AM Sat 57 57 E 7 5485 5900 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