Detailed Predictions for: Dunlap
Launch Altitude (f): 4600
LZ Altitude (f): 2200
Sounding

Station:

KVBG

Date/Time:

17 NOV 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)
4 AM Fri 44 44 S 10 2589 4600 0 Blue 0
5 AM Fri 44 44 S 10 2589 4600 0 Blue 0
6 AM Fri 44 44 S 10 2589 4600 0 Blue 0
7 AM Fri 44 44 W 8 2589 4600 0 Blue 0
8 AM Fri 46 46 W 8 3181 4600 0 Blue 0
9 AM Fri 49 49 W 8 4419 4600 0 Blue 0
10 AM Fri 50 51 SW 2 5187 4600 0 Blue 1
11 AM Fri 51 52 SW 2 5543 4600 0 Blue 2
12 Noon Fri 52 53 SW 2 5834 4814 214 White 3
1 PM Fri 52 53 W 3 5834 4814 214 White 3
2 PM Fri 51 52 W 3 5543 4600 0 Blue 2
3 PM Fri 50 50 W 3 4820 4600 0 Blue 0
4 PM Fri 49 49 NW 1 4419 4600 0 Blue 0
5 PM Fri 45 45 NW 1 2755 4600 0 Blue 0
6 PM Fri 44 44 NW 1 2589 4600 0 Blue 0
7 PM Fri 43 43 E 1 2589 4600 0 Blue 0
8 PM Fri 43 43 E 1 2589 4600 0 Blue 0
9 PM Fri 43 43 E 1 2589 4600 0 Blue 0
10 PM Fri 42 42 E 2 2589 4600 0 Blue 0
11 PM Fri 42 42 E 2 2589 4600 0 Blue 0
12 Midnight Sat 42 42 E 2 2589 4600 0 Blue 0
1 AM Sat 42 42 E 3 2589 4600 0 Blue 0
2 AM Sat 41 41 E 3 2589 4600 0 Blue 0
3 AM Sat 42 42 E 3 2589 4600 0 Blue 0
4 AM Sat 41 41 SE 3 2589 4600 0 Blue 0
5 AM Sat 41 41 SE 3 2589 4600 0 Blue 0
6 AM Sat 41 41 SE 3 2589 4600 0 Blue 0
7 AM Sat 42 42 NE 1 2589 4600 0 Blue 0
8 AM Sat 46 46 NE 1 3181 4600 0 Blue 0
9 AM Sat 51 52 NE 1 5543 4600 0 Blue 2
10 AM Sat 53 55 NW 3 6278 5530 930 White 5
11 AM Sat 54 56 NW 3 6499 5879 1279 White 6
12 Noon Sat 56 58 NW 3 6942 6564 1964 White 8
1 PM Sat 57 59 W 5 7163 6902 2302 White 9
2 PM Sat 56 57 W 5 6721 6223 1623 White 7
3 PM Sat 55 55 W 5 6278 5530 930 White 5
4 PM Sat 53 53 NW 3 5834 4814 214 White 3
5 PM Sat 48 48 NW 3 4013 4600 0 Blue 0
6 PM Sat 46 46 NW 3 3181 4600 0 Blue 0
7 PM Sat 45 45 NE 5 2755 4600 0 Blue 0
8 PM Sat 44 44 NE 5 2589 4600 0 Blue 0
9 PM Sat 45 45 NE 5 2755 4600 0 Blue 0
10 PM Sat 44 44 NE 5 2589 4600 0 Blue 0
11 PM Sat 43 43 NE 5 2589 4600 0 Blue 0
12 Midnight Sun 43 43 NE 5 2589 4600 0 Blue 0
1 AM Sun 43 43 NE 5 2589 4600 0 Blue 0
2 AM Sun 42 42 NE 5 2589 4600 0 Blue 0
3 AM Sun 43 43 NE 5 2589 4600 0 Blue 0
4 AM Sun 42 42 NE 3 2589 4600 0 Blue 0
5 AM Sun 42 42 NE 3 2589 4600 0 Blue 0
6 AM Sun 42 42 NE 3 2589 4600 0 Blue 0
7 AM Sun 43 43 NE 3 2589 4600 0 Blue 0
8 AM Sun 47 47 NE 3 3600 4600 0 Blue 0
9 AM Sun 52 53 NE 3 5834 4814 214 White 3
10 AM Sun 54 55 W 3 6278 5530 930 White 5
11 AM Sun 55 57 W 3 6721 6223 1623 White 7
12 Noon Sun 57 59 W 3 7163 6902 2302 White 9
1 PM Sun 58 59 W 3 7163 6902 2302 White 9
2 PM Sun 57 58 W 3 6942 6564 1964 White 8
3 PM Sun 56 56 W 3 6499 5879 1279 White 6
4 PM Sun 54 54 NE 2 6057 5178 578 White 4
5 PM Sun 50 50 NE 2 4820 4600 0 Blue 0
6 PM Sun 48 48 NE 2 4013 4600 0 Blue 0
7 PM Sun 47 47 NE 2 3600 4600 0 Blue 0
8 PM Sun 47 47 NE 2 3600 4600 0 Blue 0
9 PM Sun 47 47 NE 2 3600 4600 0 Blue 0
10 PM Sun 47 47 NE 3 3600 4600 0 Blue 0
11 PM Sun 46 46 NE 3 3181 4600 0 Blue 0
12 Midnight Mon 46 46 NE 3 3181 4600 0 Blue 0
1 AM Mon 46 46 NE 3 3181 4600 0 Blue 0
2 AM Mon 45 45 NE 3 2755 4600 0 Blue 0
3 AM Mon 46 46 NE 3 3181 4600 0 Blue 0
4 AM Mon 45 45 E 1 2755 4600 0 Blue 0
5 AM Mon 45 45 E 1 2755 4600 0 Blue 0
6 AM Mon 45 45 E 1 2755 4600 0 Blue 0
7 AM Mon 45 45 E 1 2755 4600 0 Blue 0
8 AM Mon 49 49 E 1 4419 4600 0 Blue 0
9 AM Mon 52 52 E 1 5543 4600 0 Blue 2
10 AM Mon 54 54 SW 2 6057 5178 578 White 4
11 AM Mon 55 55 SW 2 6278 5530 930 White 5
12 Noon Mon 57 58 SW 2 6942 6564 1964 White 8
1 PM Mon 57 57 SW 2 6721 6223 1623 White 7
2 PM Mon 57 57 SW 2 6721 6223 1623 White 7
3 PM Mon 56 56 SW 2 6499 5879 1279 White 6
4 PM Mon 54 54 N 3 6057 5178 578 White 4
5 PM Mon 51 51 N 3 5187 4600 0 Blue 1
6 PM Mon 50 50 N 3 4820 4600 0 Blue 0
7 PM Mon 49 49 N 3 4419 4600 0 Blue 0
8 PM Mon 49 49 N 3 4419 4600 0 Blue 0
9 PM Mon 49 49 N 3 4419 4600 0 Blue 0
10 PM Mon 48 48 NE 3 4013 4600 0 Blue 0
11 PM Mon 48 48 NE 3 4013 4600 0 Blue 0
12 Midnight Tue 48 48 NE 3 4013 4600 0 Blue 0
1 AM Tue 47 47 NE 3 3600 4600 0 Blue 0
2 AM Tue 47 47 NE 3 3600 4600 0 Blue 0
3 AM Tue 48 48 NE 3 4013 4600 0 Blue 0
4 AM Tue 47 47 E 5 3600 4600 0 Blue 0
5 AM Tue 47 47 E 5 3600 4600 0 Blue 0
6 AM Tue 47 47 E 5 3600 4600 0 Blue 0
7 AM Tue 48 48 E 5 4013 4600 0 Blue 0
8 AM Tue 52 52 E 5 5543 4600 0 Blue 2
9 AM Tue 57 57 E 5 6721 6223 1623 White 7
10 AM Tue 59 60 S 2 7382 7236 2636 White 10
11 AM Tue 61 62 S 2 7820 7820 3220 White 12
12 Noon Tue 63 64 S 2 8256 8256 3656 White 14
1 PM Tue 64 65 S 2 8473 8473 3873 White 15
2 PM Tue 63 64 S 2 8256 8256 3656 White 14
3 PM Tue 62 62 S 2 7820 7820 3220 White 12
4 PM Tue 61 61 S 2 7601 7601 3001 White 11
5 PM Tue 57 57 S 2 6721 6223 1623 White 7
6 PM Tue 56 56 S 2 6499 5879 1279 White 6
7 PM Tue 55 55 S 2 6278 5530 930 White 5
8 PM Tue 55 55 S 2 6278 5530 930 White 5
9 PM Tue 55 55 S 2 6278 5530 930 White 5
10 PM Tue 54 54 E 5 6057 5178 578 White 4
11 PM Tue 54 54 E 5 6057 5178 578 White 4
12 Midnight Wed 54 54 E 5 6057 5178 578 White 4
1 AM Wed 54 54 E 5 6057 5178 578 White 4
2 AM Wed 53 53 E 5 5834 4814 214 White 3
3 AM Wed 54 54 E 5 6057 5178 578 White 4
4 AM Wed 53 53 E 3 5834 4814 214 White 3
5 AM Wed 53 53 E 3 5834 4814 214 White 3
6 AM Wed 53 53 E 3 5834 4814 214 White 3
7 AM Wed 54 54 E 3 6057 5178 578 White 4
8 AM Wed 58 58 E 3 6942 6564 1964 White 8
9 AM Wed 62 62 E 3 7820 7820 3220 White 12
10 AM Wed 64 65 SW 2 8473 8473 3873 White 15
11 AM Wed 65 67 SW 2 8907 8907 4307 White 17
12 Noon Wed 68 70 SW 2 9556 9556 4956 White 20
1 PM Wed 68 70 SW 2 9556 9556 4956 White 20
2 PM Wed 67 68 SW 2 9124 9124 4524 White 18
3 PM Wed 66 66 SW 2 8690 8690 4090 White 16
4 PM Wed 64 64 N 2 8256 8256 3656 White 14
5 PM Wed 60 60 N 2 7382 7236 2636 White 10
6 PM Wed 58 58 N 2 6942 6564 1964 White 8
7 PM Wed 57 57 N 2 6721 6223 1623 White 7
8 PM Wed 57 57 N 2 6721 6223 1623 White 7
9 PM Wed 57 57 N 2 6721 6223 1623 White 7
10 PM Wed 57 57 NE 3 6721 6223 1623 White 7
11 PM Wed 56 56 NE 3 6499 5879 1279 White 6
12 Midnight Thu 56 56 NE 3 6499 5879 1279 White 6
1 AM Thu 56 56 NE 3 6499 5879 1279 White 6
2 AM Thu 55 55 NE 3 6278 5530 930 White 5
3 AM Thu 56 56 NE 3 6499 5879 1279 White 6

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