Detailed Predictions for: Weaver Bally
Launch Lat, Long, Altitude (f): 40.796231, -123.00509, 6900
LZ Altitude (f): 1480
Sounding

Station:

KOAK

Date/Time:

12 MAY 2021

Temp/Wind data from:

NOAA Digital Forecast

Site Forecasts
Time
(Local)
High
Temp

Puddle
Temp

Wind
(mph)
Wind
Gust
Thermal
Ceiling

(ft)
Soaring
Ceiling

(ft)
Above
Launch

(ft)
Thermal
Type
Thermal
Index

(F)
12 Midnight Wed 57 57 NE 3 4 5279 6900 0 Blue 0
1 AM Wed 57 57 NE 3 4 5279 6900 0 Blue 0
2 AM Wed 57 57 ENE 4 5 5279 6900 0 Blue 0
3 AM Wed 57 57 ENE 4 5 5279 6900 0 Blue 0
4 AM Wed 57 57 ENE 4 5 5279 6900 0 Blue 0
5 AM Wed 57 57 ENE 2 3 5279 6900 0 Blue 0
6 AM Wed 57 57 ENE 2 3 5279 6900 0 Blue 0
7 AM Wed 58 58 ENE 2 3 5279 6900 0 Blue 0
8 AM Wed 60 61 S 2 2 5279 6900 0 Blue 0
9 AM Wed 61 63 S 2 2 5590 6900 0 Blue 0
10 AM Wed 63 67 S 2 2 8342 6900 0 Blue 2
11 AM Wed 65 69 SW 3 4 9229 7407 507 Blue 4
12 Noon Wed 67 72 SW 3 4 10622 9216 2316 Blue 7
1 PM Wed 69 75 SW 3 4 13097 10464 3564 Blue 10
2 PM Wed 71 76 W 8 10 13806 11351 4451 Blue 11
3 PM Wed 73 77 W 8 10 14476 12162 5262 Blue 12
4 PM Wed 74 77 W 8 10 14476 12162 5262 Blue 12
5 PM Wed 74 76 W 9 11 13806 11351 4451 Blue 11
6 PM Wed 74 75 W 9 11 13097 10464 3564 Blue 10
7 PM Wed 73 73 W 9 11 11520 9321 2421 Blue 8
8 PM Wed 71 71 NW 5 6 9771 8734 1834 Blue 6
9 PM Wed 69 69 NW 5 6 9229 7407 507 Blue 4
10 PM Wed 67 67 NW 5 6 8342 6900 0 Blue 2
11 PM Wed 65 65 NNW 4 5 6173 6900 0 Blue 0
12 Midnight Thu 62 62 NNW 4 5 5296 6900 0 Blue 0
1 AM Thu 60 60 NNW 4 5 5279 6900 0 Blue 0
2 AM Thu 58 58 N 2 3 5279 6900 0 Blue 0
3 AM Thu 57 57 N 2 3 5279 6900 0 Blue 0
4 AM Thu 55 55 N 2 3 5279 6900 0 Blue 0
5 AM Thu 55 55 NNE 2 3 5279 6900 0 Blue 0
6 AM Thu 55 55 NNE 2 3 5279 6900 0 Blue 0
7 AM Thu 56 56 NNE 2 3 5279 6900 0 Blue 0
8 AM Thu 58 59 ESE 2 3 5279 6900 0 Blue 0
9 AM Thu 59 61 ESE 2 3 5279 6900 0 Blue 0
10 AM Thu 61 65 ESE 2 3 6173 6900 0 Blue 0
11 AM Thu 64 69 WSW 3 4 9229 7407 507 Blue 4
12 Noon Thu 66 72 WSW 3 4 10622 9216 2316 Blue 7
1 PM Thu 68 75 WSW 3 4 13097 10464 3564 Blue 10
2 PM Thu 69 76 WSW 8 10 13806 11351 4451 Blue 11
3 PM Thu 71 76 WSW 8 10 13806 11351 4451 Blue 11
4 PM Thu 72 76 WSW 8 10 13806 11351 4451 Blue 11
5 PM Thu 72 74 W 11 14 12339 9659 2759 Blue 9
6 PM Thu 72 73 W 11 14 11520 9321 2421 Blue 8
7 PM Thu 70 70 W 11 14 9334 8310 1410 Blue 5
8 PM Thu 69 69 W 8 10 9229 7407 507 Blue 4
9 PM Thu 67 67 W 8 10 8342 6900 0 Blue 2
10 PM Thu 65 65 W 8 10 6173 6900 0 Blue 0
11 PM Thu 63 63 NNW 8 10 5590 6900 0 Blue 0
12 Midnight Fri 60 60 NNW 8 10 5279 6900 0 Blue 0
1 AM Fri 58 58 NNW 8 10 5279 6900 0 Blue 0
2 AM Fri 56 56 NW 5 6 5279 6900 0 Blue 0
3 AM Fri 55 55 NW 5 6 5279 6900 0 Blue 0
4 AM Fri 53 53 NW 5 6 5279 6900 0 Blue 0
5 AM Fri 53 53 NNW 4 5 5279 6900 0 Blue 0
6 AM Fri 53 53 NNW 4 5 5279 6900 0 Blue 0
7 AM Fri 54 54 NNW 4 5 5279 6900 0 Blue 0
8 AM Fri 56 56 NNW 4 5 5279 6900 0 Blue 0
9 AM Fri 58 60 NNW 4 5 5279 6900 0 Blue 0
10 AM Fri 60 63 NNW 4 5 5590 6900 0 Blue 0
11 AM Fri 62 65 W 1 1 6173 6900 0 Blue 0
12 Noon Fri 64 68 W 1 1 8794 6900 0 Blue 3
1 PM Fri 66 70 W 1 1 9334 8310 1410 Blue 5
2 PM Fri 67 71 W 1 1 9771 8734 1834 Blue 6
3 PM Fri 68 71 W 1 1 9771 8734 1834 Blue 6
4 PM Fri 68 70 W 1 1 9334 8310 1410 Blue 5
5 PM Fri 68 69 NNW 8 10 9229 7407 507 Blue 4
6 PM Fri 67 67 NNW 8 10 8342 6900 0 Blue 2
7 PM Fri 66 66 NNW 8 10 7488 6900 0 Blue 1
8 PM Fri 64 64 NNW 8 10 5883 6900 0 Blue 0
9 PM Fri 62 62 NNW 8 10 5296 6900 0 Blue 0
10 PM Fri 60 60 NNW 8 10 5279 6900 0 Blue 0
11 PM Fri 58 58 N 5 6 5279 6900 0 Blue 0
12 Midnight Sat 57 57 N 5 6 5279 6900 0 Blue 0
1 AM Sat 55 55 N 5 6 5279 6900 0 Blue 0
2 AM Sat 53 53 N 5 6 5279 6900 0 Blue 0
3 AM Sat 52 52 N 5 6 5279 6900 0 Blue 0
4 AM Sat 51 51 N 5 6 5279 6900 0 Blue 0
5 AM Sat 51 51 NNE 4 5 5279 6900 0 Blue 0
6 AM Sat 51 51 NNE 4 5 5279 6900 0 Blue 0
7 AM Sat 52 52 NNE 4 5 5279 6900 0 Blue 0
8 AM Sat 53 53 NNE 4 5 5279 6900 0 Blue 0
9 AM Sat 54 55 NNE 4 5 5279 6900 0 Blue 0
10 AM Sat 56 58 NNE 4 5 5279 6900 0 Blue 0
11 AM Sat 58 63 NNE 2 3 5590 6900 0 Blue 0
12 Noon Sat 60 66 NNE 2 3 7488 6900 0 Blue 1
1 PM Sat 62 68 NNE 2 3 8794 6900 0 Blue 3
2 PM Sat 64 70 NNE 2 3 9334 8310 1410 Blue 5
3 PM Sat 66 71 NNE 2 3 9771 8734 1834 Blue 6
4 PM Sat 68 71 NNE 2 3 9771 8734 1834 Blue 6
5 PM Sat 69 71 N 4 5 9771 8734 1834 Blue 6
6 PM Sat 69 70 N 4 5 9334 8310 1410 Blue 5
7 PM Sat 68 68 N 4 5 8794 6900 0 Blue 3
8 PM Sat 67 67 N 4 5 8342 6900 0 Blue 2
9 PM Sat 65 65 N 4 5 6173 6900 0 Blue 0
10 PM Sat 63 63 N 4 5 5590 6900 0 Blue 0
11 PM Sat 61 61 N 5 6 5279 6900 0 Blue 0
12 Midnight Sun 59 59 N 5 6 5279 6900 0 Blue 0
1 AM Sun 57 57 N 5 6 5279 6900 0 Blue 0
2 AM Sun 55 55 N 5 6 5279 6900 0 Blue 0
3 AM Sun 53 53 N 5 6 5279 6900 0 Blue 0
4 AM Sun 52 52 N 5 6 5279 6900 0 Blue 0
5 AM Sun 52 52 NE 4 5 5279 6900 0 Blue 0
6 AM Sun 53 53 NE 4 5 5279 6900 0 Blue 0
7 AM Sun 54 54 NE 4 5 5279 6900 0 Blue 0
8 AM Sun 56 56 NE 4 5 5279 6900 0 Blue 0
9 AM Sun 58 59 NE 4 5 5279 6900 0 Blue 0
10 AM Sun 61 63 NE 4 5 5590 6900 0 Blue 0
11 AM Sun 64 69 ESE 1 1 9229 7407 507 Blue 4
12 Noon Sun 66 72 ESE 1 1 10622 9216 2316 Blue 7
1 PM Sun 69 75 ESE 1 1 13097 10464 3564 Blue 10
2 PM Sun 71 77 ESE 1 1 14476 12162 5262 Blue 12
3 PM Sun 72 77 ESE 1 1 14476 12162 5262 Blue 12
4 PM Sun 74 77 ESE 1 1 14476 12162 5262 Blue 12
5 PM Sun 74 76 WSW 3 4 13806 11351 4451 Blue 11
6 PM Sun 74 75 WSW 3 4 13097 10464 3564 Blue 10
7 PM Sun 73 73 WSW 3 4 11520 9321 2421 Blue 8
8 PM Sun 71 71 WSW 3 4 9771 8734 1834 Blue 6
9 PM Sun 69 69 WSW 3 4 9229 7407 507 Blue 4
10 PM Sun 67 67 WSW 3 4 8342 6900 0 Blue 2
11 PM Sun 65 65 WNW 3 4 6173 6900 0 Blue 0
12 Midnight Mon 62 62 WNW 3 4 5296 6900 0 Blue 0
1 AM Mon 60 60 WNW 3 4 5279 6900 0 Blue 0
2 AM Mon 58 58 WNW 3 4 5279 6900 0 Blue 0
3 AM Mon 56 56 WNW 3 4 5279 6900 0 Blue 0
4 AM Mon 54 54 WNW 3 4 5279 6900 0 Blue 0
5 AM Mon 53 53 NNW 1 1 5279 6900 0 Blue 0
6 AM Mon 53 53 NNW 1 1 5279 6900 0 Blue 0
7 AM Mon 53 53 NNW 1 1 5279 6900 0 Blue 0
8 AM Mon 54 54 NNW 1 1 5279 6900 0 Blue 0
9 AM Mon 55 56 NNW 1 1 5279 6900 0 Blue 0
10 AM Mon 57 59 NNW 1 1 5279 6900 0 Blue 0
11 AM Mon 59 62 WSW 2 3 5296 6900 0 Blue 0
12 Noon Mon 61 65 WSW 2 3 6173 6900 0 Blue 0
1 PM Mon 64 68 WSW 2 3 8794 6900 0 Blue 3
2 PM Mon 66 70 WSW 2 3 9334 8310 1410 Blue 5
3 PM Mon 67 71 WSW 2 3 9771 8734 1834 Blue 6
4 PM Mon 68 70 WSW 2 3 9334 8310 1410 Blue 5
5 PM Mon 68 70 W 9 11 9334 8310 1410 Blue 5
6 PM Mon 67 68 W 9 11 8794 6900 0 Blue 3
7 PM Mon 66 66 W 9 11 7488 6900 0 Blue 1
8 PM Mon 64 64 W 9 11 5883 6900 0 Blue 0
9 PM Mon 62 62 W 9 11 5296 6900 0 Blue 0
10 PM Mon 60 60 W 9 11 5279 6900 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 or WeatherAPI.com website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the National Weather Service or WeatherAPI.com 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 or WeatherAPI.com website.

Wind Gust: This estimate is taken from the National Weather Service or WeatherAPI.com 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