Detailed Predictions for: BJ
Launch Altitude (f): 582
LZ Altitude (f): 180
Sounding

Station:

KOTX

Date/Time:

26 APR 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)
5 AM Thu 50 50 NE 2 2437 2412 1830 Blue 6
6 AM Thu 50 50 NE 2 2437 2412 1830 Blue 6
7 AM Thu 51 51 NE 2 2445 2420 1838 Blue 7
8 AM Thu 51 52 N 1 2453 2428 1846 Blue 8
9 AM Thu 57 59 N 1 2567 2495 1913 Blue 15
10 AM Thu 61 64 N 1 2880 2705 2123 Blue 20
11 AM Thu 65 70 N 2 3685 3372 2790 Blue 26
12 Noon Thu 69 75 N 2 4609 3880 3298 Blue 31
1 PM Thu 74 80 N 2 7798 7275 6693 Blue 36
2 PM Thu 76 82 N 5 7900 7737 7155 Blue 38
3 PM Thu 77 82 N 5 7900 7737 7155 Blue 38
4 PM Thu 77 80 N 5 7798 7275 6693 Blue 36
5 PM Thu 76 78 N 5 7669 4523 3941 Blue 34
6 PM Thu 74 75 N 5 4609 3880 3298 Blue 31
7 PM Thu 69 69 N 5 3583 3227 2645 Blue 25
8 PM Thu 64 64 NE 7 2880 2705 2123 Blue 20
9 PM Thu 62 62 NE 7 2769 2565 1983 Blue 18
10 PM Thu 60 60 NE 7 2612 2512 1930 Blue 16
11 PM Thu 60 60 E 7 2612 2512 1930 Blue 16
12 Midnight Fri 58 58 E 7 2529 2479 1897 Blue 14
1 AM Fri 58 58 E 7 2529 2479 1897 Blue 14
2 AM Fri 56 56 E 3 2496 2460 1878 Blue 12
3 AM Fri 54 54 E 3 2469 2444 1862 Blue 10
4 AM Fri 54 54 E 3 2469 2444 1862 Blue 10
5 AM Fri 53 53 W 1 2461 2436 1854 Blue 9
6 AM Fri 53 53 W 1 2461 2436 1854 Blue 9
7 AM Fri 53 53 W 1 2461 2436 1854 Blue 9
8 AM Fri 54 55 S 2 2480 2452 1870 Blue 11
9 AM Fri 57 59 S 2 2567 2495 1913 Blue 15
10 AM Fri 60 63 S 2 2824 2610 2028 Blue 19
11 AM Fri 63 67 SW 5 3379 2877 2295 Blue 23
12 Noon Fri 66 71 SW 5 3787 3474 2892 Blue 27
1 PM Fri 69 74 SW 5 4274 3778 3196 Blue 30
2 PM Fri 70 75 SW 9 4609 3880 3298 Blue 31
3 PM Fri 70 74 SW 9 4274 3778 3196 Blue 30
4 PM Fri 70 73 SW 9 3993 3677 3095 Blue 29
5 PM Fri 69 70 S 14 3685 3372 2790 Blue 26
6 PM Fri 67 67 S 14 3379 2877 2295 Blue 23
7 PM Fri 63 63 S 14 2824 2610 2028 Blue 19
8 PM Fri 59 59 S 12 2567 2495 1913 Blue 15
9 PM Fri 57 57 S 12 2512 2468 1886 Blue 13
10 PM Fri 55 55 S 12 2480 2452 1870 Blue 11
11 PM Fri 55 55 S 10 2480 2452 1870 Blue 11
12 Midnight Sat 54 54 S 10 2469 2444 1862 Blue 10
1 AM Sat 53 53 S 10 2461 2436 1854 Blue 9
2 AM Sat 51 51 S 7 2445 2420 1838 Blue 7
3 AM Sat 50 50 S 7 2437 2412 1830 Blue 6
4 AM Sat 49 49 S 7 2429 2404 1822 Blue 5
5 AM Sat 49 49 S 3 2429 2404 1822 Blue 5
6 AM Sat 48 48 S 3 2421 2396 1814 Blue 4
7 AM Sat 48 48 S 3 2421 2396 1814 Blue 4
8 AM Sat 49 49 S 5 2429 2404 1822 Blue 5
9 AM Sat 50 50 S 5 2437 2412 1830 Blue 6
10 AM Sat 51 51 S 5 2445 2420 1838 Blue 7
11 AM Sat 52 52 S 8 2453 2428 1846 Blue 8
12 Noon Sat 53 53 S 8 2461 2436 1854 Blue 9
1 PM Sat 55 55 S 8 2480 2452 1870 Blue 11
2 PM Sat 55 55 S 9 2480 2452 1870 Blue 11
3 PM Sat 55 55 S 9 2480 2452 1870 Blue 11
4 PM Sat 55 55 S 9 2480 2452 1870 Blue 11
5 PM Sat 55 55 S 8 2480 2452 1870 Blue 11
6 PM Sat 54 54 S 8 2469 2444 1862 Blue 10
7 PM Sat 52 52 S 8 2453 2428 1846 Blue 8
8 PM Sat 50 50 S 7 2437 2412 1830 Blue 6
9 PM Sat 49 49 S 7 2429 2404 1822 Blue 5
10 PM Sat 48 48 S 7 2421 2396 1814 Blue 4
11 PM Sat 48 48 S 7 2421 2396 1814 Blue 4
12 Midnight Sun 48 48 S 7 2421 2396 1814 Blue 4
1 AM Sun 47 47 S 7 2413 2389 1807 Blue 3
2 AM Sun 46 46 S 9 2405 2388 1806 Blue 2
3 AM Sun 46 46 S 9 2405 2388 1806 Blue 2
4 AM Sun 46 46 S 9 2405 2388 1806 Blue 2
5 AM Sun 45 45 S 5 2397 2388 1806 Blue 1
6 AM Sun 45 45 S 5 2397 2388 1806 Blue 1
7 AM Sun 45 45 S 5 2397 2388 1806 Blue 1
8 AM Sun 45 45 S 5 2397 2388 1806 Blue 1
9 AM Sun 47 47 S 5 2413 2389 1807 Blue 3
10 AM Sun 47 47 S 5 2413 2389 1807 Blue 3
11 AM Sun 48 48 SW 6 2421 2396 1814 Blue 4
12 Noon Sun 49 49 SW 6 2429 2404 1822 Blue 5
1 PM Sun 50 50 SW 6 2437 2412 1830 Blue 6
2 PM Sun 50 50 SW 6 2437 2412 1830 Blue 6
3 PM Sun 50 50 SW 6 2437 2412 1830 Blue 6
4 PM Sun 50 50 SW 6 2437 2412 1830 Blue 6
5 PM Sun 50 50 SW 7 2437 2412 1830 Blue 6
6 PM Sun 50 50 SW 7 2437 2412 1830 Blue 6
7 PM Sun 48 48 SW 7 2421 2396 1814 Blue 4
8 PM Sun 47 47 SW 7 2413 2389 1807 Blue 3
9 PM Sun 46 46 SW 7 2405 2388 1806 Blue 2
10 PM Sun 46 46 SW 7 2405 2388 1806 Blue 2
11 PM Sun 46 46 S 6 2405 2388 1806 Blue 2
12 Midnight Mon 46 46 S 6 2405 2388 1806 Blue 2
1 AM Mon 46 46 S 6 2405 2388 1806 Blue 2
2 AM Mon 45 45 S 6 2397 2388 1806 Blue 1
3 AM Mon 45 45 S 6 2397 2388 1806 Blue 1
4 AM Mon 44 44 S 6 2389 2388 1806 Blue 0
5 AM Mon 44 44 S 6 2389 2388 1806 Blue 0
6 AM Mon 44 44 S 6 2389 2388 1806 Blue 0
7 AM Mon 44 44 S 6 2389 2388 1806 Blue 0
8 AM Mon 45 45 S 6 2397 2388 1806 Blue 1
9 AM Mon 46 46 S 6 2405 2388 1806 Blue 2
10 AM Mon 48 48 S 6 2421 2396 1814 Blue 4
11 AM Mon 49 49 SW 7 2429 2404 1822 Blue 5
12 Noon Mon 50 50 SW 7 2437 2412 1830 Blue 6
1 PM Mon 51 51 SW 7 2445 2420 1838 Blue 7
2 PM Mon 52 52 SW 7 2453 2428 1846 Blue 8
3 PM Mon 52 52 SW 7 2453 2428 1846 Blue 8
4 PM Mon 52 52 SW 7 2453 2428 1846 Blue 8
5 PM Mon 52 52 SW 7 2453 2428 1846 Blue 8
6 PM Mon 51 51 SW 7 2445 2420 1838 Blue 7
7 PM Mon 49 49 SW 7 2429 2404 1822 Blue 5
8 PM Mon 48 48 SW 7 2421 2396 1814 Blue 4
9 PM Mon 47 47 SW 7 2413 2389 1807 Blue 3
10 PM Mon 46 46 SW 7 2405 2388 1806 Blue 2
11 PM Mon 46 46 S 5 2405 2388 1806 Blue 2
12 Midnight Tue 45 45 S 5 2397 2388 1806 Blue 1
1 AM Tue 45 45 S 5 2397 2388 1806 Blue 1
2 AM Tue 44 44 S 5 2389 2388 1806 Blue 0
3 AM Tue 44 44 S 5 2389 2388 1806 Blue 0
4 AM Tue 44 44 S 5 2389 2388 1806 Blue 0
5 AM Tue 43 43 S 6 0 582 0 Blue 0
6 AM Tue 44 44 S 6 2389 2388 1806 Blue 0
7 AM Tue 44 44 S 6 2389 2388 1806 Blue 0
8 AM Tue 44 44 S 6 2389 2388 1806 Blue 0
9 AM Tue 47 47 S 6 2413 2389 1807 Blue 3
10 AM Tue 49 49 S 6 2429 2404 1822 Blue 5
11 AM Tue 51 52 W 7 2453 2428 1846 Blue 8
12 Noon Tue 53 54 W 7 2469 2444 1862 Blue 10
1 PM Tue 55 56 W 7 2496 2460 1878 Blue 12
2 PM Tue 57 58 W 7 2529 2479 1897 Blue 14
3 PM Tue 57 58 W 7 2529 2479 1897 Blue 14
4 PM Tue 57 57 W 7 2512 2468 1886 Blue 13
5 PM Tue 56 57 W 7 2512 2468 1886 Blue 13
6 PM Tue 55 55 W 7 2480 2452 1870 Blue 11
7 PM Tue 52 52 W 7 2453 2428 1846 Blue 8
8 PM Tue 49 49 W 7 2429 2404 1822 Blue 5
9 PM Tue 48 48 W 7 2421 2396 1814 Blue 4
10 PM Tue 47 47 W 7 2413 2389 1807 Blue 3
11 PM Tue 47 47 SE 5 2413 2389 1807 Blue 3
12 Midnight Wed 46 46 SE 5 2405 2388 1806 Blue 2
1 AM Wed 45 45 SE 5 2397 2388 1806 Blue 1
2 AM Wed 44 44 SE 5 2389 2388 1806 Blue 0
3 AM Wed 43 43 SE 5 0 582 0 Blue 0
4 AM Wed 43 43 SE 5 0 582 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