Detailed Predictions for: Ed Levin
Launch Altitude (f): 2150
LZ Altitude (f): 400
Sounding

Station:

KOAK

Date/Time:

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)
5 AM Sat 51 51 N 15 1106 2150 0 Blue 0
6 AM Sat 51 51 N 15 1106 2150 0 Blue 0
7 AM Sat 52 52 N 15 1106 2150 0 Blue 0
8 AM Sat 53 53 N 12 1106 2150 0 Blue 0
9 AM Sat 56 57 N 12 2044 2150 0 Blue 0
10 AM Sat 59 61 N 12 4086 2617 467 Blue 4
11 AM Sat 63 67 NW 13 7507 6083 3933 White 10
12 Noon Sat 65 70 NW 13 8134 7710 5560 White 13
1 PM Sat 68 74 NW 13 8967 8967 6817 White 17
2 PM Sat 69 74 NW 18 8967 8967 6817 White 17
3 PM Sat 70 74 NW 18 8967 8967 6817 White 17
4 PM Sat 70 73 NW 18 8759 8759 6609 White 16
5 PM Sat 69 70 NW 20 8134 7710 5560 White 13
6 PM Sat 66 66 NW 20 7144 5073 2923 Blue 9
7 PM Sat 62 62 NW 20 4342 3025 875 Blue 5
8 PM Sat 59 59 NW 14 3063 2150 0 Blue 2
9 PM Sat 58 58 NW 14 2622 2150 0 Blue 1
10 PM Sat 57 57 NW 14 2044 2150 0 Blue 0
11 PM Sat 58 58 N 7 2622 2150 0 Blue 1
12 Midnight Sun 57 57 N 7 2044 2150 0 Blue 0
1 AM Sun 57 57 N 7 2044 2150 0 Blue 0
2 AM Sun 57 57 N 5 2044 2150 0 Blue 0
3 AM Sun 56 56 N 5 1683 2150 0 Blue 0
4 AM Sun 55 55 N 5 1318 2150 0 Blue 0
5 AM Sun 54 54 N 8 1106 2150 0 Blue 0
6 AM Sun 54 54 N 8 1106 2150 0 Blue 0
7 AM Sun 55 55 N 8 1318 2150 0 Blue 0
8 AM Sun 56 56 N 9 1683 2150 0 Blue 0
9 AM Sun 59 60 N 9 3850 2150 0 Blue 3
10 AM Sun 63 65 N 9 6730 4321 2171 Blue 8
11 AM Sun 66 70 N 12 8134 7710 5560 White 13
12 Noon Sun 69 74 N 12 8967 8967 6817 White 17
1 PM Sun 71 76 N 12 9378 9378 7228 White 19
2 PM Sun 73 78 N 15 9789 9789 7639 White 21
3 PM Sun 74 78 N 15 9789 9789 7639 White 21
4 PM Sun 75 78 N 15 9789 9789 7639 White 21
5 PM Sun 74 75 NW 17 9173 9173 7023 White 18
6 PM Sun 71 71 NW 17 8344 8344 6194 White 14
7 PM Sun 67 67 NW 17 7507 6083 3933 White 10
8 PM Sun 64 64 NW 17 6142 4069 1919 Blue 7
9 PM Sun 62 62 NW 17 4342 3025 875 Blue 5
10 PM Sun 61 61 NW 17 4086 2617 467 Blue 4
11 PM Sun 61 61 N 10 4086 2617 467 Blue 4
12 Midnight Mon 61 61 N 10 4086 2617 467 Blue 4
1 AM Mon 60 60 N 10 3850 2150 0 Blue 3
2 AM Mon 60 60 N 10 3850 2150 0 Blue 3
3 AM Mon 59 59 N 10 3063 2150 0 Blue 2
4 AM Mon 58 58 N 10 2622 2150 0 Blue 1
5 AM Mon 58 58 N 14 2622 2150 0 Blue 1
6 AM Mon 57 57 N 14 2044 2150 0 Blue 0
7 AM Mon 57 57 N 14 2044 2150 0 Blue 0
8 AM Mon 58 58 N 14 2622 2150 0 Blue 1
9 AM Mon 61 62 N 14 4342 3025 875 Blue 5
10 AM Mon 65 67 N 14 7507 6083 3933 White 10
11 AM Mon 69 73 N 14 8759 8759 6609 White 16
12 Noon Mon 73 78 N 14 9789 9789 7639 White 21
1 PM Mon 75 80 N 14 10217 10217 8067 White 23
2 PM Mon 77 82 N 14 10621 10621 8471 White 25
3 PM Mon 78 82 N 14 10621 10621 8471 White 25
4 PM Mon 78 81 N 14 10419 10419 8269 White 24
5 PM Mon 78 79 NW 15 10014 10014 7864 White 22
6 PM Mon 75 75 NW 15 9173 9173 7023 White 18
7 PM Mon 73 73 NW 15 8759 8759 6609 White 16
8 PM Mon 70 70 NW 15 8134 7710 5560 White 13
9 PM Mon 69 69 NW 15 7925 7072 4922 White 12
10 PM Mon 68 68 NW 15 7716 6663 4513 White 11
11 PM Mon 68 68 N 8 7716 6663 4513 White 11
12 Midnight Tue 67 67 N 8 7507 6083 3933 White 10
1 AM Tue 67 67 N 8 7507 6083 3933 White 10
2 AM Tue 67 67 N 8 7507 6083 3933 White 10
3 AM Tue 66 66 N 8 7144 5073 2923 Blue 9
4 AM Tue 65 65 N 8 6730 4321 2171 Blue 8
5 AM Tue 64 64 N 7 6142 4069 1919 Blue 7
6 AM Tue 61 61 N 7 4086 2617 467 Blue 4
7 AM Tue 60 60 N 7 3850 2150 0 Blue 3
8 AM Tue 60 60 N 7 3850 2150 0 Blue 3
9 AM Tue 64 65 N 7 6730 4321 2171 Blue 8
10 AM Tue 68 70 N 7 8134 7710 5560 White 13
11 AM Tue 73 77 N 3 9583 9583 7433 White 20
12 Noon Tue 77 82 N 3 10621 10621 8471 White 25
1 PM Tue 79 85 N 3 11222 11222 9072 White 28
2 PM Tue 81 86 N 3 11421 11421 9271 White 29
3 PM Tue 83 87 N 3 11619 11619 9469 White 30
4 PM Tue 83 86 N 3 11421 11421 9271 White 29
5 PM Tue 82 83 N 7 10821 10821 8671 White 26
6 PM Tue 79 79 N 7 10014 10014 7864 White 22
7 PM Tue 75 75 N 7 9173 9173 7023 White 18
8 PM Tue 72 72 N 7 8552 8552 6402 White 15
9 PM Tue 70 70 N 7 8134 7710 5560 White 13
10 PM Tue 70 70 N 7 8134 7710 5560 White 13
11 PM Tue 69 69 W 2 7925 7072 4922 White 12
12 Midnight Wed 67 67 W 2 7507 6083 3933 White 10
1 AM Wed 65 65 W 2 6730 4321 2171 Blue 8
2 AM Wed 64 64 W 2 6142 4069 1919 Blue 7
3 AM Wed 64 64 W 2 6142 4069 1919 Blue 7
4 AM Wed 66 66 W 2 7144 5073 2923 Blue 9
5 AM Wed 66 66 E 2 7144 5073 2923 Blue 9
6 AM Wed 65 65 E 2 6730 4321 2171 Blue 8
7 AM Wed 64 64 E 2 6142 4069 1919 Blue 7
8 AM Wed 64 64 E 2 6142 4069 1919 Blue 7
9 AM Wed 68 69 E 2 7925 7072 4922 White 12
10 AM Wed 74 76 E 2 9378 9378 7228 White 19
11 AM Wed 79 82 E 2 10621 10621 8471 White 25
12 Noon Wed 82 86 E 2 11421 11421 9271 White 29
1 PM Wed 84 88 E 2 11817 11817 9667 White 31
2 PM Wed 85 89 E 2 12015 12015 9865 White 32
3 PM Wed 86 89 E 2 12015 12015 9865 White 32
4 PM Wed 86 88 E 2 11817 11817 9667 White 31
5 PM Wed 85 86 W 6 11421 11421 9271 White 29
6 PM Wed 82 82 W 6 10621 10621 8471 White 25
7 PM Wed 78 78 W 6 9789 9789 7639 White 21
8 PM Wed 75 75 W 6 9173 9173 7023 White 18
9 PM Wed 73 73 W 6 8759 8759 6609 White 16
10 PM Wed 73 73 W 6 8759 8759 6609 White 16
11 PM Wed 72 72 W 1 8552 8552 6402 White 15
12 Midnight Thu 70 70 W 1 8134 7710 5560 White 13
1 AM Thu 67 67 W 1 7507 6083 3933 White 10
2 AM Thu 66 66 W 1 7144 5073 2923 Blue 9
3 AM Thu 66 66 W 1 7144 5073 2923 Blue 9
4 AM Thu 68 68 W 1 7716 6663 4513 White 11
5 AM Thu 68 68 E 1 7716 6663 4513 White 11
6 AM Thu 66 66 E 1 7144 5073 2923 Blue 9
7 AM Thu 64 64 E 1 6142 4069 1919 Blue 7
8 AM Thu 65 65 E 1 6730 4321 2171 Blue 8
9 AM Thu 69 69 E 1 7925 7072 4922 White 12
10 AM Thu 75 77 E 1 9583 9583 7433 White 20
11 AM Thu 81 84 NE 1 11022 11022 8872 White 27
12 Noon Thu 83 87 NE 1 11619 11619 9469 White 30
1 PM Thu 84 88 NE 1 11817 11817 9667 White 31
2 PM Thu 84 88 NE 1 11817 11817 9667 White 31
3 PM Thu 85 88 NE 1 11817 11817 9667 White 31
4 PM Thu 86 88 NE 1 11817 11817 9667 White 31
5 PM Thu 85 86 W 8 11421 11421 9271 White 29
6 PM Thu 82 82 W 8 10621 10621 8471 White 25
7 PM Thu 77 77 W 8 9583 9583 7433 White 20
8 PM Thu 74 74 W 8 8967 8967 6817 White 17
9 PM Thu 73 73 W 8 8759 8759 6609 White 16
10 PM Thu 73 73 W 8 8759 8759 6609 White 16
11 PM Thu 73 73 W 3 8759 8759 6609 White 16
12 Midnight Fri 71 71 W 3 8344 8344 6194 White 14
1 AM Fri 68 68 W 3 7716 6663 4513 White 11
2 AM Fri 66 66 W 3 7144 5073 2923 Blue 9
3 AM Fri 67 67 W 3 7507 6083 3933 White 10
4 AM Fri 69 69 W 3 7925 7072 4922 White 12

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