Detailed Predictions for: Lake Isabella Ground Launch Center
Launch Altitude (f): 5000
LZ Altitude (f): 2591
Sounding

Station:

KVBG

Date/Time:

13 NOV 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)
4 AM Tue 39 39 SE 12 2874 5000 0 Blue 0
5 AM Tue 39 39 SE 12 2874 5000 0 Blue 0
6 AM Tue 37 37 SE 12 2874 5000 0 Blue 0
7 AM Tue 39 39 S 15 2874 5000 0 Blue 0
8 AM Tue 43 43 S 15 2874 5000 0 Blue 0
9 AM Tue 50 51 S 15 2874 5000 0 Blue 0
10 AM Tue 56 57 SE 16 2874 5000 0 Blue 0
11 AM Tue 60 62 SE 16 3715 5000 0 Blue 0
12 Noon Tue 62 64 SE 16 4354 5000 0 Blue 0
1 PM Tue 63 65 SE 16 4670 5000 0 Blue 0
2 PM Tue 64 65 SE 16 4670 5000 0 Blue 0
3 PM Tue 64 64 SE 16 4354 5000 0 Blue 0
4 PM Tue 62 62 SE 13 3715 5000 0 Blue 0
5 PM Tue 59 59 SE 13 2874 5000 0 Blue 0
6 PM Tue 55 55 SE 13 2874 5000 0 Blue 0
7 PM Tue 51 51 SE 10 2874 5000 0 Blue 0
8 PM Tue 49 49 SE 10 2874 5000 0 Blue 0
9 PM Tue 47 47 SE 10 2874 5000 0 Blue 0
10 PM Tue 46 46 SE 8 2874 5000 0 Blue 0
11 PM Tue 45 45 SE 8 2874 5000 0 Blue 0
12 Midnight Wed 44 44 SE 8 2874 5000 0 Blue 0
1 AM Wed 44 44 SE 7 2874 5000 0 Blue 0
2 AM Wed 44 44 SE 7 2874 5000 0 Blue 0
3 AM Wed 43 43 SE 7 2874 5000 0 Blue 0
4 AM Wed 43 43 E 7 2874 5000 0 Blue 0
5 AM Wed 41 41 E 7 2874 5000 0 Blue 0
6 AM Wed 40 40 E 7 2874 5000 0 Blue 0
7 AM Wed 41 41 E 6 2874 5000 0 Blue 0
8 AM Wed 46 46 E 6 2874 5000 0 Blue 0
9 AM Wed 53 54 E 6 2874 5000 0 Blue 0
10 AM Wed 60 62 S 3 3715 5000 0 Blue 0
11 AM Wed 65 67 S 3 5279 5000 0 Blue 0
12 Noon Wed 68 70 S 3 6145 5258 258 Blue 3
1 PM Wed 69 71 S 5 6429 5546 546 Blue 4
2 PM Wed 70 71 S 5 6429 5546 546 Blue 4
3 PM Wed 69 69 S 5 5858 5000 0 Blue 2
4 PM Wed 67 67 S 6 5279 5000 0 Blue 0
5 PM Wed 64 64 S 6 4354 5000 0 Blue 0
6 PM Wed 60 60 S 6 3066 5000 0 Blue 0
7 PM Wed 56 56 S 6 2874 5000 0 Blue 0
8 PM Wed 53 53 S 6 2874 5000 0 Blue 0
9 PM Wed 50 50 S 6 2874 5000 0 Blue 0
10 PM Wed 49 49 NE 6 2874 5000 0 Blue 0
11 PM Wed 48 48 NE 6 2874 5000 0 Blue 0
12 Midnight Thu 47 47 NE 6 2874 5000 0 Blue 0
1 AM Thu 47 47 NE 6 2874 5000 0 Blue 0
2 AM Thu 46 46 NE 6 2874 5000 0 Blue 0
3 AM Thu 44 44 NE 6 2874 5000 0 Blue 0
4 AM Thu 43 43 NE 6 2874 5000 0 Blue 0
5 AM Thu 42 42 NE 6 2874 5000 0 Blue 0
6 AM Thu 42 42 NE 6 2874 5000 0 Blue 0
7 AM Thu 44 44 NE 6 2874 5000 0 Blue 0
8 AM Thu 49 49 NE 6 2874 5000 0 Blue 0
9 AM Thu 56 57 NE 6 2874 5000 0 Blue 0
10 AM Thu 62 64 E 7 4354 5000 0 Blue 0
11 AM Thu 67 69 E 7 5858 5000 0 Blue 2
12 Noon Thu 70 72 E 7 6712 5832 832 Blue 5
1 PM Thu 71 73 E 7 7024 6116 1116 Blue 6
2 PM Thu 72 73 E 7 7024 6116 1116 Blue 6
3 PM Thu 71 71 E 7 6429 5546 546 Blue 4
4 PM Thu 69 69 S 3 5858 5000 0 Blue 2
5 PM Thu 66 66 S 3 4983 5000 0 Blue 0
6 PM Thu 61 61 S 3 3392 5000 0 Blue 0
7 PM Thu 57 57 S 3 2874 5000 0 Blue 0
8 PM Thu 54 54 S 3 2874 5000 0 Blue 0
9 PM Thu 52 52 S 3 2874 5000 0 Blue 0
10 PM Thu 50 50 NW 1 2874 5000 0 Blue 0
11 PM Thu 49 49 NW 1 2874 5000 0 Blue 0
12 Midnight Fri 49 49 NW 1 2874 5000 0 Blue 0
1 AM Fri 48 48 NW 1 2874 5000 0 Blue 0
2 AM Fri 47 47 NW 1 2874 5000 0 Blue 0
3 AM Fri 46 46 NW 1 2874 5000 0 Blue 0
4 AM Fri 44 44 NE 5 2874 5000 0 Blue 0
5 AM Fri 42 42 NE 5 2874 5000 0 Blue 0
6 AM Fri 41 41 NE 5 2874 5000 0 Blue 0
7 AM Fri 42 42 NE 5 2874 5000 0 Blue 0
8 AM Fri 46 46 NE 5 2874 5000 0 Blue 0
9 AM Fri 53 54 NE 5 2874 5000 0 Blue 0
10 AM Fri 59 61 S 2 3392 5000 0 Blue 0
11 AM Fri 64 66 S 2 4983 5000 0 Blue 0
12 Noon Fri 67 70 S 2 6145 5258 258 Blue 3
1 PM Fri 69 71 S 2 6429 5546 546 Blue 4
2 PM Fri 70 71 S 2 6429 5546 546 Blue 4
3 PM Fri 70 70 S 2 6145 5258 258 Blue 3
4 PM Fri 68 68 S 6 5570 5000 0 Blue 1
5 PM Fri 63 63 S 6 4036 5000 0 Blue 0
6 PM Fri 58 58 S 6 2874 5000 0 Blue 0
7 PM Fri 54 54 S 6 2874 5000 0 Blue 0
8 PM Fri 51 51 S 6 2874 5000 0 Blue 0
9 PM Fri 50 50 S 6 2874 5000 0 Blue 0
10 PM Fri 49 49 NE 5 2874 5000 0 Blue 0
11 PM Fri 47 47 NE 5 2874 5000 0 Blue 0
12 Midnight Sat 46 46 NE 5 2874 5000 0 Blue 0
1 AM Sat 45 45 NE 5 2874 5000 0 Blue 0
2 AM Sat 44 44 NE 5 2874 5000 0 Blue 0
3 AM Sat 43 43 NE 5 2874 5000 0 Blue 0
4 AM Sat 42 42 E 5 2874 5000 0 Blue 0
5 AM Sat 40 40 E 5 2874 5000 0 Blue 0
6 AM Sat 39 39 E 5 2874 5000 0 Blue 0
7 AM Sat 40 40 E 5 2874 5000 0 Blue 0
8 AM Sat 44 44 E 5 2874 5000 0 Blue 0
9 AM Sat 50 51 E 5 2874 5000 0 Blue 0
10 AM Sat 57 59 S 5 2874 5000 0 Blue 0
11 AM Sat 62 64 S 5 4354 5000 0 Blue 0
12 Noon Sat 66 68 S 5 5570 5000 0 Blue 1
1 PM Sat 68 70 S 5 6145 5258 258 Blue 3
2 PM Sat 69 70 S 5 6145 5258 258 Blue 3
3 PM Sat 68 68 S 5 5570 5000 0 Blue 1
4 PM Sat 66 66 SE 7 4983 5000 0 Blue 0
5 PM Sat 61 61 SE 7 3392 5000 0 Blue 0
6 PM Sat 57 57 SE 7 2874 5000 0 Blue 0
7 PM Sat 52 52 SE 7 2874 5000 0 Blue 0
8 PM Sat 50 50 SE 7 2874 5000 0 Blue 0
9 PM Sat 48 48 SE 7 2874 5000 0 Blue 0
10 PM Sat 47 47 E 5 2874 5000 0 Blue 0
11 PM Sat 46 46 E 5 2874 5000 0 Blue 0
12 Midnight Sun 45 45 E 5 2874 5000 0 Blue 0
1 AM Sun 44 44 E 5 2874 5000 0 Blue 0
2 AM Sun 43 43 E 5 2874 5000 0 Blue 0
3 AM Sun 43 43 E 5 2874 5000 0 Blue 0
4 AM Sun 43 43 NE 5 2874 5000 0 Blue 0
5 AM Sun 41 41 NE 5 2874 5000 0 Blue 0
6 AM Sun 41 41 NE 5 2874 5000 0 Blue 0
7 AM Sun 43 43 NE 5 2874 5000 0 Blue 0
8 AM Sun 47 47 NE 5 2874 5000 0 Blue 0
9 AM Sun 53 54 NE 5 2874 5000 0 Blue 0
10 AM Sun 59 61 E 8 3392 5000 0 Blue 0
11 AM Sun 63 65 E 8 4670 5000 0 Blue 0
12 Noon Sun 66 68 E 8 5570 5000 0 Blue 1
1 PM Sun 67 69 E 8 5858 5000 0 Blue 2
2 PM Sun 67 68 E 8 5570 5000 0 Blue 1
3 PM Sun 66 66 E 8 4983 5000 0 Blue 0
4 PM Sun 64 64 E 10 4354 5000 0 Blue 0
5 PM Sun 61 61 E 10 3392 5000 0 Blue 0
6 PM Sun 58 58 E 10 2874 5000 0 Blue 0
7 PM Sun 54 54 E 10 2874 5000 0 Blue 0
8 PM Sun 52 52 E 10 2874 5000 0 Blue 0
9 PM Sun 50 50 E 10 2874 5000 0 Blue 0
10 PM Sun 49 49 E 6 2874 5000 0 Blue 0
11 PM Sun 48 48 E 6 2874 5000 0 Blue 0
12 Midnight Mon 47 47 E 6 2874 5000 0 Blue 0
1 AM Mon 47 47 E 6 2874 5000 0 Blue 0
2 AM Mon 46 46 E 6 2874 5000 0 Blue 0
3 AM Mon 46 46 E 6 2874 5000 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