Detailed Predictions for: Goat Mountain
Launch Altitude (f): 4000
LZ Altitude (f): 2500
Sounding

Station:

KOAK

Date/Time:

26 MAY 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 Sun 41 41 NW 8 4576 4000 0 Blue 0
6 AM Sun 41 41 NW 8 4576 4000 0 Blue 0
7 AM Sun 41 41 NW 8 4576 4000 0 Blue 0
8 AM Sun 43 43 W 10 4991 4206 206 Blue 2
9 AM Sun 45 45 W 10 5401 4776 776 Blue 4
10 AM Sun 47 48 W 10 6740 5387 1387 White 7
11 AM Sun 48 49 W 16 6956 5590 1590 White 8
12 Noon Sun 49 50 W 16 7172 5871 1871 White 9
1 PM Sun 49 53 W 16 7815 7698 3698 White 12
2 PM Sun 50 53 W 15 7815 7698 3698 White 12
3 PM Sun 50 53 W 15 7815 7698 3698 White 12
4 PM Sun 50 52 W 15 7601 7324 3324 White 11
5 PM Sun 49 49 NW 15 6956 5590 1590 White 8
6 PM Sun 48 48 NW 15 6740 5387 1387 White 7
7 PM Sun 46 46 NW 15 5605 4980 980 Blue 5
8 PM Sun 44 44 NW 13 5196 4562 562 Blue 3
9 PM Sun 42 42 NW 13 4785 4000 0 Blue 1
10 PM Sun 40 40 NW 13 4216 4000 0 Blue 0
11 PM Sun 39 39 NW 10 3851 4000 0 Blue 0
12 Midnight Mon 39 39 NW 10 3851 4000 0 Blue 0
1 AM Mon 39 39 NW 10 3851 4000 0 Blue 0
2 AM Mon 38 38 NW 9 3482 4000 0 Blue 0
3 AM Mon 38 38 NW 9 3482 4000 0 Blue 0
4 AM Mon 38 38 NW 9 3482 4000 0 Blue 0
5 AM Mon 38 38 NW 6 3482 4000 0 Blue 0
6 AM Mon 38 38 NW 6 3482 4000 0 Blue 0
7 AM Mon 38 38 NW 6 3482 4000 0 Blue 0
8 AM Mon 42 42 NW 8 4785 4000 0 Blue 1
9 AM Mon 47 47 NW 8 5937 5184 1184 Blue 6
10 AM Mon 51 52 NW 8 7601 7324 3324 White 11
11 AM Mon 53 54 NW 8 8028 8028 4028 White 13
12 Noon Mon 56 58 NW 8 8879 8879 4879 White 17
1 PM Mon 57 59 NW 8 9094 9094 5094 White 18
2 PM Mon 58 60 NW 6 9309 9309 5309 White 19
3 PM Mon 59 61 NW 6 9524 9524 5524 White 20
4 PM Mon 59 60 NW 6 9309 9309 5309 White 19
5 PM Mon 57 57 N 7 8664 8664 4664 White 16
6 PM Mon 56 56 N 7 8452 8452 4452 White 15
7 PM Mon 54 54 N 7 8028 8028 4028 White 13
8 PM Mon 50 50 NE 6 7172 5871 1871 White 9
9 PM Mon 47 47 NE 6 5937 5184 1184 Blue 6
10 PM Mon 46 46 NE 6 5605 4980 980 Blue 5
11 PM Mon 44 44 N 6 5196 4562 562 Blue 3
12 Midnight Tue 44 44 N 6 5196 4562 562 Blue 3
1 AM Tue 43 43 N 6 4991 4206 206 Blue 2
2 AM Tue 43 43 N 6 4991 4206 206 Blue 2
3 AM Tue 43 43 N 6 4991 4206 206 Blue 2
4 AM Tue 42 42 N 6 4785 4000 0 Blue 1
5 AM Tue 42 42 N 8 4785 4000 0 Blue 1
6 AM Tue 42 42 N 8 4785 4000 0 Blue 1
7 AM Tue 42 42 N 8 4785 4000 0 Blue 1
8 AM Tue 48 48 N 9 6740 5387 1387 White 7
9 AM Tue 53 54 N 9 8028 8028 4028 White 13
10 AM Tue 58 60 N 9 9309 9309 5309 White 19
11 AM Tue 61 67 N 9 10766 10766 6766 White 26
12 Noon Tue 65 72 N 9 11791 11710 7710 White 31
1 PM Tue 66 73 N 9 11996 11968 7968 White 32
2 PM Tue 67 75 N 7 12403 12403 8403 White 34
3 PM Tue 68 74 N 7 12200 12200 8200 White 33
4 PM Tue 69 73 N 7 11996 11968 7968 White 32
5 PM Tue 66 68 N 9 10970 10970 6970 White 27
6 PM Tue 64 65 N 9 10355 10355 6355 White 24
7 PM Tue 61 61 N 9 9524 9524 5524 White 20
8 PM Tue 57 57 N 8 8664 8664 4664 White 16
9 PM Tue 53 53 N 8 7815 7698 3698 White 12
10 PM Tue 51 51 N 8 7387 6621 2621 White 10
11 PM Tue 49 49 NW 3 6956 5590 1590 White 8
12 Midnight Wed 49 49 NW 3 6956 5590 1590 White 8
1 AM Wed 48 48 NW 3 6740 5387 1387 White 7
2 AM Wed 48 48 W 2 6740 5387 1387 White 7
3 AM Wed 47 47 W 2 5937 5184 1184 Blue 6
4 AM Wed 46 46 W 2 5605 4980 980 Blue 5
5 AM Wed 47 47 E 2 5937 5184 1184 Blue 6
6 AM Wed 46 46 E 2 5605 4980 980 Blue 5
7 AM Wed 47 47 E 2 5937 5184 1184 Blue 6
8 AM Wed 52 53 W 3 7815 7698 3698 White 12
9 AM Wed 58 61 W 3 9524 9524 5524 White 20
10 AM Wed 63 67 W 3 10766 10766 6766 White 26
11 AM Wed 66 71 N 7 11586 11586 7586 White 30
12 Noon Wed 69 75 N 7 12403 12403 8403 White 34
1 PM Wed 70 77 N 7 12811 12811 8811 White 35
2 PM Wed 72 73 NW 8 11996 11968 7968 White 32
3 PM Wed 72 73 NW 8 11996 11968 7968 White 32
4 PM Wed 73 74 NW 8 12200 12200 8200 White 33
5 PM Wed 70 71 NW 9 11586 11586 7586 White 30
6 PM Wed 68 68 NW 9 10970 10970 6970 White 27
7 PM Wed 65 65 NW 9 10355 10355 6355 White 24
8 PM Wed 60 60 NW 7 9309 9309 5309 White 19
9 PM Wed 56 56 NW 7 8452 8452 4452 White 15
10 PM Wed 54 54 NW 7 8028 8028 4028 White 13
11 PM Wed 51 51 W 5 7387 6621 2621 White 10
12 Midnight Thu 51 51 W 5 7387 6621 2621 White 10
1 AM Thu 50 50 W 5 7172 5871 1871 White 9
2 AM Thu 50 50 W 5 7172 5871 1871 White 9
3 AM Thu 49 49 W 5 6956 5590 1590 White 8
4 AM Thu 48 48 W 5 6740 5387 1387 White 7
5 AM Thu 48 48 W 5 6740 5387 1387 White 7
6 AM Thu 48 48 W 5 6740 5387 1387 White 7
7 AM Thu 48 48 W 5 6740 5387 1387 White 7
8 AM Thu 54 55 W 3 8240 8240 4240 White 14
9 AM Thu 59 62 W 3 9735 9735 5735 White 21
10 AM Thu 63 68 W 3 10970 10970 6970 White 27
11 AM Thu 66 72 NW 7 11791 11710 7710 White 31
12 Noon Thu 69 77 NW 7 12811 12811 8811 White 35
1 PM Thu 70 78 NW 7 13014 13014 9014 White 36
2 PM Thu 72 79 W 8 13214 13214 9214 White 37
3 PM Thu 72 78 W 8 13014 13014 9014 White 36
4 PM Thu 73 77 W 8 12811 12811 8811 White 35
5 PM Thu 70 72 NW 10 11791 11710 7710 White 31
6 PM Thu 68 69 NW 10 11176 11176 7176 White 28
7 PM Thu 65 65 NW 10 10355 10355 6355 White 24
8 PM Thu 60 60 W 7 9309 9309 5309 White 19
9 PM Thu 56 56 W 7 8452 8452 4452 White 15
10 PM Thu 53 53 W 7 7815 7698 3698 White 12
11 PM Thu 51 51 W 6 7387 6621 2621 White 10
12 Midnight Fri 51 51 W 6 7387 6621 2621 White 10
1 AM Fri 50 50 W 6 7172 5871 1871 White 9
2 AM Fri 50 50 W 6 7172 5871 1871 White 9
3 AM Fri 49 49 W 6 6956 5590 1590 White 8
4 AM Fri 48 48 W 6 6740 5387 1387 White 7
5 AM Fri 48 48 W 6 6740 5387 1387 White 7
6 AM Fri 48 48 W 6 6740 5387 1387 White 7
7 AM Fri 48 48 W 6 6740 5387 1387 White 7
8 AM Fri 54 54 W 5 8028 8028 4028 White 13
9 AM Fri 59 60 W 5 9309 9309 5309 White 19
10 AM Fri 64 67 W 5 10766 10766 6766 White 26
11 AM Fri 67 70 N 7 11380 11380 7380 White 29
12 Noon Fri 70 74 N 7 12200 12200 8200 White 33
1 PM Fri 71 75 N 7 12403 12403 8403 White 34
2 PM Fri 73 77 W 9 12811 12811 8811 White 35
3 PM Fri 73 76 W 9 12607 12607 8607 White 34
4 PM Fri 74 76 W 9 12607 12607 8607 White 34
5 PM Fri 72 74 W 9 12200 12200 8200 White 33
6 PM Fri 69 69 W 9 11176 11176 7176 White 28
7 PM Fri 66 66 W 9 10561 10561 6561 White 25
8 PM Fri 61 61 W 7 9524 9524 5524 White 20
9 PM Fri 58 58 W 7 8879 8879 4879 White 17
10 PM Fri 55 55 W 7 8240 8240 4240 White 14
11 PM Fri 53 53 W 7 7815 7698 3698 White 12
12 Midnight Sat 53 53 W 7 7815 7698 3698 White 12
1 AM Sat 52 52 W 7 7601 7324 3324 White 11
2 AM Sat 52 52 W 6 7601 7324 3324 White 11
3 AM Sat 51 51 W 6 7387 6621 2621 White 10
4 AM Sat 50 50 W 6 7172 5871 1871 White 9

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