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

Station:

KVBG

Date/Time:

4 DEC 2020

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 50 50 NE 3 2884 4600 0 Blue 0
5 AM Fri 49 49 E 1 2884 4600 0 Blue 0
6 AM Fri 49 49 E 2 2884 4600 0 Blue 0
7 AM Fri 48 48 E 2 2884 4600 0 Blue 0
8 AM Fri 46 46 NE 2 2884 4600 0 Blue 0
9 AM Fri 47 47 E 1 2884 4600 0 Blue 0
10 AM Fri 49 50 SW 2 2884 4600 0 Blue 0
11 AM Fri 49 50 W 3 2884 4600 0 Blue 0
12 Noon Fri 49 51 SW 5 2915 4600 0 Blue 0
1 PM Fri 50 51 W 5 2915 4600 0 Blue 0
2 PM Fri 50 51 W 5 2915 4600 0 Blue 0
3 PM Fri 50 50 W 3 2884 4600 0 Blue 0
4 PM Fri 48 48 N 2 2884 4600 0 Blue 0
5 PM Fri 47 47 NE 5 2884 4600 0 Blue 0
6 PM Fri 48 48 NE 2 2884 4600 0 Blue 0
7 PM Fri 48 48 E 3 2884 4600 0 Blue 0
8 PM Fri 49 49 E 2 2884 4600 0 Blue 0
9 PM Fri 49 49 E 2 2884 4600 0 Blue 0
10 PM Fri 49 49 E 3 2884 4600 0 Blue 0
11 PM Fri 48 48 E 2 2884 4600 0 Blue 0
12 Midnight Sat 49 49 E 2 2884 4600 0 Blue 0
1 AM Sat 49 49 E 3 2884 4600 0 Blue 0
2 AM Sat 50 50 E 2 2884 4600 0 Blue 0
3 AM Sat 50 50 E 3 2884 4600 0 Blue 0
4 AM Sat 50 50 E 5 2884 4600 0 Blue 0
5 AM Sat 50 50 SE 3 2884 4600 0 Blue 0
6 AM Sat 50 50 SE 3 2884 4600 0 Blue 0
7 AM Sat 49 49 SE 5 2884 4600 0 Blue 0
8 AM Sat 48 48 SE 3 2884 4600 0 Blue 0
9 AM Sat 49 49 S 3 2884 4600 0 Blue 0
10 AM Sat 50 51 SW 5 2915 4600 0 Blue 0
11 AM Sat 51 52 SW 5 3163 4600 0 Blue 0
12 Noon Sat 52 53 SW 5 3410 4600 0 Blue 0
1 PM Sat 52 53 SW 5 3410 4600 0 Blue 0
2 PM Sat 51 52 SW 5 3163 4600 0 Blue 0
3 PM Sat 50 50 SW 5 2884 4600 0 Blue 0
4 PM Sat 49 49 SW 2 2884 4600 0 Blue 0
5 PM Sat 49 49 SW 2 2884 4600 0 Blue 0
6 PM Sat 49 49 SW 2 2884 4600 0 Blue 0
7 PM Sat 49 49 E 3 2884 4600 0 Blue 0
8 PM Sat 49 49 E 3 2884 4600 0 Blue 0
9 PM Sat 49 49 E 3 2884 4600 0 Blue 0
10 PM Sat 49 49 NE 5 2884 4600 0 Blue 0
11 PM Sat 49 49 NE 5 2884 4600 0 Blue 0
12 Midnight Sun 49 49 NE 5 2884 4600 0 Blue 0
1 AM Sun 49 49 NE 6 2884 4600 0 Blue 0
2 AM Sun 49 49 NE 6 2884 4600 0 Blue 0
3 AM Sun 48 48 NE 6 2884 4600 0 Blue 0
4 AM Sun 48 48 NE 3 2884 4600 0 Blue 0
5 AM Sun 47 47 NE 3 2884 4600 0 Blue 0
6 AM Sun 47 47 NE 3 2884 4600 0 Blue 0
7 AM Sun 46 46 E 3 2884 4600 0 Blue 0
8 AM Sun 45 45 E 3 2884 4600 0 Blue 0
9 AM Sun 44 44 E 3 2884 4600 0 Blue 0
10 AM Sun 44 45 W 5 2884 4600 0 Blue 0
11 AM Sun 44 45 W 5 2884 4600 0 Blue 0
12 Noon Sun 45 46 W 5 2884 4600 0 Blue 0
1 PM Sun 45 46 W 5 2884 4600 0 Blue 0
2 PM Sun 45 45 W 5 2884 4600 0 Blue 0
3 PM Sun 44 44 W 5 2884 4600 0 Blue 0
4 PM Sun 44 44 S 5 2884 4600 0 Blue 0
5 PM Sun 44 44 S 5 2884 4600 0 Blue 0
6 PM Sun 44 44 S 5 2884 4600 0 Blue 0
7 PM Sun 44 44 E 6 2884 4600 0 Blue 0
8 PM Sun 44 44 E 6 2884 4600 0 Blue 0
9 PM Sun 44 44 E 6 2884 4600 0 Blue 0
10 PM Sun 44 44 E 6 2884 4600 0 Blue 0
11 PM Sun 45 45 E 6 2884 4600 0 Blue 0
12 Midnight Mon 45 45 E 6 2884 4600 0 Blue 0
1 AM Mon 46 46 E 8 2884 4600 0 Blue 0
2 AM Mon 47 47 E 8 2884 4600 0 Blue 0
3 AM Mon 47 47 E 8 2884 4600 0 Blue 0
4 AM Mon 47 47 NE 12 2884 4600 0 Blue 0
5 AM Mon 46 46 NE 12 2884 4600 0 Blue 0
6 AM Mon 46 46 NE 12 2884 4600 0 Blue 0
7 AM Mon 45 45 NE 6 2884 4600 0 Blue 0
8 AM Mon 45 45 NE 6 2884 4600 0 Blue 0
9 AM Mon 45 45 NE 6 2884 4600 0 Blue 0
10 AM Mon 46 47 NE 3 2884 4600 0 Blue 0
11 AM Mon 47 48 NE 3 2884 4600 0 Blue 0
12 Noon Mon 47 49 NE 3 2884 4600 0 Blue 0
1 PM Mon 48 49 NW 6 2884 4600 0 Blue 0
2 PM Mon 48 49 NW 6 2884 4600 0 Blue 0
3 PM Mon 48 48 NW 6 2884 4600 0 Blue 0
4 PM Mon 48 48 SE 3 2884 4600 0 Blue 0
5 PM Mon 48 48 SE 3 2884 4600 0 Blue 0
6 PM Mon 48 48 SE 3 2884 4600 0 Blue 0
7 PM Mon 48 48 NE 5 2884 4600 0 Blue 0
8 PM Mon 48 48 NE 5 2884 4600 0 Blue 0
9 PM Mon 48 48 NE 5 2884 4600 0 Blue 0
10 PM Mon 48 48 NE 6 2884 4600 0 Blue 0
11 PM Mon 48 48 NE 6 2884 4600 0 Blue 0
12 Midnight Tue 49 49 NE 6 2884 4600 0 Blue 0
1 AM Tue 49 49 NE 6 2884 4600 0 Blue 0
2 AM Tue 49 49 NE 6 2884 4600 0 Blue 0
3 AM Tue 49 49 NE 6 2884 4600 0 Blue 0
4 AM Tue 49 49 NE 5 2884 4600 0 Blue 0
5 AM Tue 49 49 NE 5 2884 4600 0 Blue 0
6 AM Tue 48 48 NE 5 2884 4600 0 Blue 0
7 AM Tue 48 48 E 6 2884 4600 0 Blue 0
8 AM Tue 48 48 E 6 2884 4600 0 Blue 0
9 AM Tue 49 49 E 6 2884 4600 0 Blue 0
10 AM Tue 50 51 SE 3 2915 4600 0 Blue 0
11 AM Tue 51 53 SE 3 3410 4600 0 Blue 0
12 Noon Tue 52 54 SE 3 3656 4600 0 Blue 0
1 PM Tue 53 54 W 5 3656 4600 0 Blue 0
2 PM Tue 53 54 W 5 3656 4600 0 Blue 0
3 PM Tue 52 52 W 5 3163 4600 0 Blue 0
4 PM Tue 51 51 E 1 2915 4600 0 Blue 0
5 PM Tue 51 51 E 1 2915 4600 0 Blue 0
6 PM Tue 51 51 E 1 2915 4600 0 Blue 0
7 PM Tue 51 51 NE 2 2915 4600 0 Blue 0
8 PM Tue 51 51 NE 2 2915 4600 0 Blue 0
9 PM Tue 51 51 NE 2 2915 4600 0 Blue 0
10 PM Tue 51 51 E 3 2915 4600 0 Blue 0
11 PM Tue 51 51 E 3 2915 4600 0 Blue 0
12 Midnight Wed 52 52 E 3 3163 4600 0 Blue 0
1 AM Wed 52 52 E 3 3163 4600 0 Blue 0
2 AM Wed 52 52 E 3 3163 4600 0 Blue 0
3 AM Wed 52 52 E 3 3163 4600 0 Blue 0
4 AM Wed 52 52 NE 3 3163 4600 0 Blue 0
5 AM Wed 51 51 NE 3 2915 4600 0 Blue 0
6 AM Wed 51 51 NE 3 2915 4600 0 Blue 0
7 AM Wed 50 50 E 3 2884 4600 0 Blue 0
8 AM Wed 49 49 E 3 2884 4600 0 Blue 0
9 AM Wed 49 49 E 3 2884 4600 0 Blue 0
10 AM Wed 49 50 SW 2 2884 4600 0 Blue 0
11 AM Wed 50 51 SW 2 2915 4600 0 Blue 0
12 Noon Wed 50 52 SW 2 3163 4600 0 Blue 0
1 PM Wed 51 52 W 5 3163 4600 0 Blue 0
2 PM Wed 51 52 W 5 3163 4600 0 Blue 0
3 PM Wed 50 50 W 5 2884 4600 0 Blue 0
4 PM Wed 50 50 W 2 2884 4600 0 Blue 0
5 PM Wed 50 50 W 2 2884 4600 0 Blue 0
6 PM Wed 49 49 W 2 2884 4600 0 Blue 0
7 PM Wed 49 49 NE 2 2884 4600 0 Blue 0
8 PM Wed 49 49 NE 2 2884 4600 0 Blue 0
9 PM Wed 48 48 NE 2 2884 4600 0 Blue 0
10 PM Wed 48 48 E 2 2884 4600 0 Blue 0
11 PM Wed 48 48 E 2 2884 4600 0 Blue 0
12 Midnight Thu 48 48 E 2 2884 4600 0 Blue 0
1 AM Thu 48 48 E 2 2884 4600 0 Blue 0
2 AM Thu 48 48 E 2 2884 4600 0 Blue 0
3 AM Thu 48 48 E 2 2884 4600 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