Detailed Predictions for: The Y
Launch Altitude (f): 4900
LZ Altitude (f): 3150
Sounding

Station:

KTUS

Date/Time:

12Z 23 SEP 2017

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 Sat 53 53 S 6 3999 4900 0 Blue 0
7 AM Sat 53 53 S 5 3999 4900 0 Blue 0
8 AM Sat 55 55 SE 5 3999 4900 0 Blue 0
9 AM Sat 57 59 S 6 3999 4900 0 Blue 0
10 AM Sat 60 63 S 7 4445 4900 0 Blue 0
11 AM Sat 63 68 S 9 7884 6222 1322 Blue 4
12 Noon Sat 66 72 S 12 10116 8718 3818 Blue 8
1 PM Sat 68 74 S 13 10563 9667 4767 Blue 10
2 PM Sat 70 75 SW 13 10893 10076 5176 Blue 11
3 PM Sat 72 75 SW 13 10893 10076 5176 Blue 11
4 PM Sat 73 75 SW 12 10893 10076 5176 Blue 11
5 PM Sat 73 73 SW 12 10323 9279 4379 Blue 9
6 PM Sat 72 72 W 12 10116 8718 3818 Blue 8
7 PM Sat 71 71 W 10 9736 7800 2900 Blue 7
8 PM Sat 69 69 W 9 8862 6883 1983 Blue 5
9 PM Sat 67 67 NW 9 7353 5142 242 Blue 3
10 PM Sat 66 66 NW 8 6918 4900 0 Blue 2
11 PM Sat 65 65 NW 7 6313 4900 0 Blue 1
12 Midnight Sun 64 64 NW 6 5177 4900 0 Blue 0
1 AM Sun 62 62 NW 6 3999 4900 0 Blue 0
2 AM Sun 61 61 N 5 3999 4900 0 Blue 0
3 AM Sun 59 59 N 6 3999 4900 0 Blue 0
4 AM Sun 57 57 N 7 3999 4900 0 Blue 0
5 AM Sun 55 55 N 8 3999 4900 0 Blue 0
6 AM Sun 54 54 N 8 3999 4900 0 Blue 0
7 AM Sun 53 53 N 6 3999 4900 0 Blue 0
8 AM Sun 53 53 N 6 3999 4900 0 Blue 0
9 AM Sun 55 57 N 6 3999 4900 0 Blue 0
10 AM Sun 58 62 NW 6 3999 4900 0 Blue 0
11 AM Sun 62 67 NW 6 7353 5142 242 Blue 3
12 Noon Sun 66 72 NW 5 10116 8718 3818 Blue 8
1 PM Sun 68 74 NW 7 10563 9667 4767 Blue 10
2 PM Sun 70 75 NW 8 10893 10076 5176 Blue 11
3 PM Sun 72 76 W 8 11046 10281 5381 Blue 12
4 PM Sun 73 75 NW 9 10893 10076 5176 Blue 11
5 PM Sun 75 75 NW 10 10893 10076 5176 Blue 11
6 PM Sun 75 75 W 10 10893 10076 5176 Blue 11
7 PM Sun 74 74 NW 12 10563 9667 4767 Blue 10
8 PM Sun 72 72 NW 10 10116 8718 3818 Blue 8
9 PM Sun 69 69 NW 8 8862 6883 1983 Blue 5
10 PM Sun 66 66 N 10 6918 4900 0 Blue 2
11 PM Sun 64 64 N 10 5177 4900 0 Blue 0
12 Midnight Mon 62 62 N 8 3999 4900 0 Blue 0
1 AM Mon 60 60 N 9 3999 4900 0 Blue 0
2 AM Mon 59 59 N 10 3999 4900 0 Blue 0
3 AM Mon 58 58 NE 9 3999 4900 0 Blue 0
4 AM Mon 56 56 NE 10 3999 4900 0 Blue 0
5 AM Mon 55 55 NE 10 3999 4900 0 Blue 0
6 AM Mon 54 54 NE 9 3999 4900 0 Blue 0
7 AM Mon 54 54 NE 9 3999 4900 0 Blue 0
8 AM Mon 55 55 NE 8 3999 4900 0 Blue 0
9 AM Mon 58 60 NE 8 3999 4900 0 Blue 0
10 AM Mon 61 64 N 6 5177 4900 0 Blue 0
11 AM Mon 66 71 N 5 9736 7800 2900 Blue 7
12 Noon Mon 70 76 E 3 11046 10281 5381 Blue 12
1 PM Mon 72 78 N 3 11445 10859 5959 Blue 14
2 PM Mon 74 79 N 5 11831 11012 6112 Blue 15
3 PM Mon 75 78 W 3 11445 10859 5959 Blue 14
4 PM Mon 76 78 NW 6 11445 10859 5959 Blue 14
5 PM Mon 77 77 NW 7 11199 10486 5586 Blue 13
6 PM Mon 77 77 W 7 11199 10486 5586 Blue 13
7 PM Mon 75 75 NW 8 10893 10076 5176 Blue 11
8 PM Mon 73 73 NW 8 10323 9279 4379 Blue 9
9 PM Mon 71 71 NW 8 9736 7800 2900 Blue 7
10 PM Mon 69 69 N 8 8862 6883 1983 Blue 5
11 PM Mon 68 68 N 8 7884 6222 1322 Blue 4
12 Midnight Tue 67 67 N 7 7353 5142 242 Blue 3
1 AM Tue 64 64 N 9 5177 4900 0 Blue 0
2 AM Tue 61 61 N 9 3999 4900 0 Blue 0
3 AM Tue 59 59 NE 9 3999 4900 0 Blue 0
4 AM Tue 57 57 NE 9 3999 4900 0 Blue 0
5 AM Tue 56 56 NE 9 3999 4900 0 Blue 0
6 AM Tue 56 56 NE 8 3999 4900 0 Blue 0
7 AM Tue 58 58 NE 8 3999 4900 0 Blue 0
8 AM Tue 60 60 NE 7 3999 4900 0 Blue 0
9 AM Tue 63 65 NE 6 6313 4900 0 Blue 1
10 AM Tue 66 69 NE 3 8862 6883 1983 Blue 5
11 AM Tue 69 74 N 2 10563 9667 4767 Blue 10
12 Noon Tue 72 78 SE 3 11445 10859 5959 Blue 14
1 PM Tue 75 81 N 2 12596 11353 6453 Blue 17
2 PM Tue 77 82 N 3 12972 11735 6835 Blue 18
3 PM Tue 78 81 NW 5 12596 11353 6453 Blue 17
4 PM Tue 79 81 W 6 12596 11353 6453 Blue 17
5 PM Tue 79 79 W 7 11831 11012 6112 Blue 15
6 PM Tue 79 79 SW 7 11831 11012 6112 Blue 15
7 PM Tue 77 77 W 8 11199 10486 5586 Blue 13
8 PM Tue 76 76 W 8 11046 10281 5381 Blue 12
9 PM Tue 74 74 NW 8 10563 9667 4767 Blue 10
10 PM Tue 71 71 NW 7 9736 7800 2900 Blue 7
11 PM Tue 69 69 NW 7 8862 6883 1983 Blue 5
12 Midnight Wed 66 66 NW 5 6918 4900 0 Blue 2
1 AM Wed 63 63 N 6 4445 4900 0 Blue 0
2 AM Wed 61 61 N 7 3999 4900 0 Blue 0
3 AM Wed 59 59 NE 7 3999 4900 0 Blue 0
4 AM Wed 58 58 NE 7 3999 4900 0 Blue 0
5 AM Wed 58 58 E 7 3999 4900 0 Blue 0
6 AM Wed 59 59 E 7 3999 4900 0 Blue 0
7 AM Wed 60 60 NE 6 3999 4900 0 Blue 0
8 AM Wed 63 63 N 5 4445 4900 0 Blue 0
9 AM Wed 66 68 N 3 7884 6222 1322 Blue 4
10 AM Wed 69 72 NW 2 10116 8718 3818 Blue 8
11 AM Wed 72 76 W 1 11046 10281 5381 Blue 12
12 Noon Wed 75 79 S 3 11831 11012 6112 Blue 15
1 PM Wed 77 81 W 1 12596 11353 6453 Blue 17
2 PM Wed 79 83 W 3 13398 12113 7213 Blue 19
3 PM Wed 80 83 W 5 13398 12113 7213 Blue 19
4 PM Wed 80 81 W 7 12596 11353 6453 Blue 17
5 PM Wed 80 80 W 8 12214 11164 6264 Blue 16
6 PM Wed 79 79 W 9 11831 11012 6112 Blue 15
7 PM Wed 77 77 W 10 11199 10486 5586 Blue 13
8 PM Wed 75 75 W 9 10893 10076 5176 Blue 11
9 PM Wed 73 73 NW 9 10323 9279 4379 Blue 9
10 PM Wed 70 70 NW 8 9344 7309 2409 Blue 6
11 PM Wed 67 67 N 8 7353 5142 242 Blue 3
12 Midnight Thu 65 65 N 6 6313 4900 0 Blue 1
1 AM Thu 63 63 N 8 4445 4900 0 Blue 0
2 AM Thu 62 62 N 8 3999 4900 0 Blue 0
3 AM Thu 61 61 NE 9 3999 4900 0 Blue 0
4 AM Thu 60 60 NE 9 3999 4900 0 Blue 0
5 AM Thu 60 60 NE 10 3999 4900 0 Blue 0
6 AM Thu 60 60 E 12 3999 4900 0 Blue 0
7 AM Thu 61 61 NE 9 3999 4900 0 Blue 0
8 AM Thu 62 62 NE 9 3999 4900 0 Blue 0
9 AM Thu 63 64 NE 8 5177 4900 0 Blue 0
10 AM Thu 65 67 NE 8 7353 5142 242 Blue 3
11 AM Thu 67 70 NE 7 9344 7309 2409 Blue 6
12 Noon Thu 69 73 E 9 10323 9279 4379 Blue 9
1 PM Thu 72 76 NE 6 11046 10281 5381 Blue 12
2 PM Thu 75 78 NE 5 11445 10859 5959 Blue 14
3 PM Thu 78 80 NE 5 12214 11164 6264 Blue 16
4 PM Thu 80 81 N 5 12596 11353 6453 Blue 17
5 PM Thu 81 81 N 5 12596 11353 6453 Blue 17
6 PM Thu 81 81 NW 5 12596 11353 6453 Blue 17
7 PM Thu 80 80 N 5 12214 11164 6264 Blue 16
8 PM Thu 78 78 N 6 11445 10859 5959 Blue 14
9 PM Thu 76 76 NE 7 11046 10281 5381 Blue 12
10 PM Thu 74 74 NE 8 10563 9667 4767 Blue 10
11 PM Thu 71 71 NE 9 9736 7800 2900 Blue 7
12 Midnight Fri 68 68 NE 9 7884 6222 1322 Blue 4
1 AM Fri 66 66 NE 10 6918 4900 0 Blue 2
2 AM Fri 64 64 NE 10 5177 4900 0 Blue 0
3 AM Fri 63 63 NE 12 4445 4900 0 Blue 0
4 AM Fri 62 62 NE 12 3999 4900 0 Blue 0
5 AM Fri 61 61 E 12 3999 4900 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