Detailed Predictions for: Dunlap
Launch Altitude (f): 4460
LZ Altitude (f): 1950
Sounding

Station:

KOAK

Date/Time:

25 NOV 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 Wed 45 40 E 1 2087 4460 0 Blue 0
5 AM Wed 44 39 E 1 2087 4460 0 Blue 0
6 AM Wed 44 39 N 0 2087 4460 0 Blue 0
7 AM Wed 43 38 SE 2 2087 4460 0 Blue 0
8 AM Wed 45 40 SE 1 2087 4460 0 Blue 0
9 AM Wed 48 44 S 1 2087 4460 0 Blue 0
10 AM Wed 51 47 SW 3 2465 4460 0 Blue 0
11 AM Wed 52 49 SW 5 3438 4460 0 Blue 2
12 Noon Wed 53 50 W 6 3563 4460 0 Blue 3
1 PM Wed 53 50 W 8 3563 4460 0 Blue 3
2 PM Wed 53 49 W 7 3438 4460 0 Blue 2
3 PM Wed 52 47 W 7 2465 4460 0 Blue 0
4 PM Wed 50 45 W 7 2130 4460 0 Blue 0
5 PM Wed 47 42 NW 6 2087 4460 0 Blue 0
6 PM Wed 44 39 NW 5 2087 4460 0 Blue 0
7 PM Wed 43 38 E 1 2087 4460 0 Blue 0
8 PM Wed 42 37 E 3 2087 4460 0 Blue 0
9 PM Wed 42 37 E 5 2087 4460 0 Blue 0
10 PM Wed 42 37 E 3 2087 4460 0 Blue 0
11 PM Wed 41 36 E 3 2087 4460 0 Blue 0
12 Midnight Thu 41 36 E 3 2087 4460 0 Blue 0
1 AM Thu 40 35 E 2 2087 4460 0 Blue 0
2 AM Thu 40 35 E 3 2087 4460 0 Blue 0
3 AM Thu 41 36 E 3 2087 4460 0 Blue 0
4 AM Thu 40 35 N 1 2087 4460 0 Blue 0
5 AM Thu 38 33 N 1 2087 4460 0 Blue 0
6 AM Thu 38 33 N 2 2087 4460 0 Blue 0
7 AM Thu 37 32 NW 2 2087 4460 0 Blue 0
8 AM Thu 39 34 NW 2 2087 4460 0 Blue 0
9 AM Thu 42 37 NW 2 2087 4460 0 Blue 0
10 AM Thu 45 41 W 2 2087 4460 0 Blue 0
11 AM Thu 47 44 W 2 2087 4460 0 Blue 0
12 Noon Thu 48 45 W 2 2130 4460 0 Blue 0
1 PM Thu 49 46 W 3 2284 4460 0 Blue 0
2 PM Thu 49 45 W 3 2130 4460 0 Blue 0
3 PM Thu 48 43 W 3 2087 4460 0 Blue 0
4 PM Thu 46 41 W 2 2087 4460 0 Blue 0
5 PM Thu 44 39 W 2 2087 4460 0 Blue 0
6 PM Thu 42 37 W 2 2087 4460 0 Blue 0
7 PM Thu 40 35 E 3 2087 4460 0 Blue 0
8 PM Thu 39 34 E 3 2087 4460 0 Blue 0
9 PM Thu 39 34 E 3 2087 4460 0 Blue 0
10 PM Thu 39 34 NE 3 2087 4460 0 Blue 0
11 PM Thu 39 34 NE 3 2087 4460 0 Blue 0
12 Midnight Fri 40 35 NE 3 2087 4460 0 Blue 0
1 AM Fri 40 35 N 2 2087 4460 0 Blue 0
2 AM Fri 40 35 N 2 2087 4460 0 Blue 0
3 AM Fri 40 35 N 2 2087 4460 0 Blue 0
4 AM Fri 40 35 NE 3 2087 4460 0 Blue 0
5 AM Fri 39 34 NE 3 2087 4460 0 Blue 0
6 AM Fri 39 34 NE 3 2087 4460 0 Blue 0
7 AM Fri 39 34 SE 2 2087 4460 0 Blue 0
8 AM Fri 42 37 SE 2 2087 4460 0 Blue 0
9 AM Fri 45 40 SE 2 2087 4460 0 Blue 0
10 AM Fri 49 45 SW 2 2130 4460 0 Blue 0
11 AM Fri 51 48 SW 2 3151 4460 0 Blue 1
12 Noon Fri 53 50 SW 2 3563 4460 0 Blue 3
1 PM Fri 54 51 W 3 3689 4460 0 Blue 4
2 PM Fri 54 50 W 3 3563 4460 0 Blue 3
3 PM Fri 53 48 W 3 3151 4460 0 Blue 1
4 PM Fri 51 46 W 1 2284 4460 0 Blue 0
5 PM Fri 49 44 W 1 2087 4460 0 Blue 0
6 PM Fri 47 42 W 1 2087 4460 0 Blue 0
7 PM Fri 45 40 E 2 2087 4460 0 Blue 0
8 PM Fri 44 39 E 2 2087 4460 0 Blue 0
9 PM Fri 44 39 E 2 2087 4460 0 Blue 0
10 PM Fri 44 39 E 2 2087 4460 0 Blue 0
11 PM Fri 44 39 E 2 2087 4460 0 Blue 0
12 Midnight Sat 45 40 E 2 2087 4460 0 Blue 0
1 AM Sat 45 40 E 2 2087 4460 0 Blue 0
2 AM Sat 45 40 E 2 2087 4460 0 Blue 0
3 AM Sat 46 41 E 2 2087 4460 0 Blue 0
4 AM Sat 46 41 E 2 2087 4460 0 Blue 0
5 AM Sat 45 40 E 2 2087 4460 0 Blue 0
6 AM Sat 44 39 E 2 2087 4460 0 Blue 0
7 AM Sat 44 39 E 2 2087 4460 0 Blue 0
8 AM Sat 46 41 E 2 2087 4460 0 Blue 0
9 AM Sat 50 45 E 2 2130 4460 0 Blue 0
10 AM Sat 53 49 SW 3 3438 4460 0 Blue 2
11 AM Sat 55 52 SW 3 3814 4460 0 Blue 5
12 Noon Sat 57 54 SW 3 4065 4460 0 Blue 7
1 PM Sat 57 54 W 3 4065 4460 0 Blue 7
2 PM Sat 56 52 W 3 3814 4460 0 Blue 5
3 PM Sat 55 50 W 3 3563 4460 0 Blue 3
4 PM Sat 53 48 W 2 3151 4460 0 Blue 1
5 PM Sat 51 46 W 2 2284 4460 0 Blue 0
6 PM Sat 49 44 W 2 2087 4460 0 Blue 0
7 PM Sat 48 43 E 2 2087 4460 0 Blue 0
8 PM Sat 47 42 E 2 2087 4460 0 Blue 0
9 PM Sat 46 41 E 2 2087 4460 0 Blue 0
10 PM Sat 46 41 E 3 2087 4460 0 Blue 0
11 PM Sat 46 41 E 3 2087 4460 0 Blue 0
12 Midnight Sun 46 41 E 3 2087 4460 0 Blue 0
1 AM Sun 46 41 E 3 2087 4460 0 Blue 0
2 AM Sun 46 41 E 3 2087 4460 0 Blue 0
3 AM Sun 46 41 E 3 2087 4460 0 Blue 0
4 AM Sun 46 41 E 5 2087 4460 0 Blue 0
5 AM Sun 45 40 E 5 2087 4460 0 Blue 0
6 AM Sun 45 40 E 5 2087 4460 0 Blue 0
7 AM Sun 45 40 E 5 2087 4460 0 Blue 0
8 AM Sun 48 43 E 5 2087 4460 0 Blue 0
9 AM Sun 52 47 E 5 2465 4460 0 Blue 0
10 AM Sun 55 51 SW 3 3689 4460 0 Blue 4
11 AM Sun 57 53 SW 3 3940 4460 0 Blue 6
12 Noon Sun 59 55 SW 3 4191 4460 0 Blue 8
1 PM Sun 59 55 W 3 4191 4460 0 Blue 8
2 PM Sun 58 54 W 3 4065 4460 0 Blue 7
3 PM Sun 57 52 W 3 3814 4460 0 Blue 5
4 PM Sun 55 50 W 2 3563 4460 0 Blue 3
5 PM Sun 53 48 W 2 3151 4460 0 Blue 1
6 PM Sun 51 46 W 2 2284 4460 0 Blue 0
7 PM Sun 49 44 NE 2 2087 4460 0 Blue 0
8 PM Sun 48 43 NE 2 2087 4460 0 Blue 0
9 PM Sun 48 43 NE 2 2087 4460 0 Blue 0
10 PM Sun 48 43 E 3 2087 4460 0 Blue 0
11 PM Sun 48 43 E 3 2087 4460 0 Blue 0
12 Midnight Mon 48 43 E 3 2087 4460 0 Blue 0
1 AM Mon 48 43 NE 5 2087 4460 0 Blue 0
2 AM Mon 48 43 NE 5 2087 4460 0 Blue 0
3 AM Mon 48 43 NE 5 2087 4460 0 Blue 0
4 AM Mon 48 43 E 5 2087 4460 0 Blue 0
5 AM Mon 47 42 E 5 2087 4460 0 Blue 0
6 AM Mon 46 41 E 5 2087 4460 0 Blue 0
7 AM Mon 46 41 E 5 2087 4460 0 Blue 0
8 AM Mon 48 43 E 5 2087 4460 0 Blue 0
9 AM Mon 50 45 E 5 2130 4460 0 Blue 0
10 AM Mon 53 49 SW 3 3438 4460 0 Blue 2
11 AM Mon 55 51 SW 3 3689 4460 0 Blue 4
12 Noon Mon 56 53 SW 3 3940 4460 0 Blue 6
1 PM Mon 56 52 W 5 3814 4460 0 Blue 5
2 PM Mon 56 52 W 5 3814 4460 0 Blue 5
3 PM Mon 55 50 W 5 3563 4460 0 Blue 3
4 PM Mon 53 48 W 2 3151 4460 0 Blue 1
5 PM Mon 51 46 W 2 2284 4460 0 Blue 0
6 PM Mon 49 44 W 2 2087 4460 0 Blue 0
7 PM Mon 47 42 NE 2 2087 4460 0 Blue 0
8 PM Mon 46 41 NE 2 2087 4460 0 Blue 0
9 PM Mon 45 40 NE 2 2087 4460 0 Blue 0
10 PM Mon 45 40 NE 3 2087 4460 0 Blue 0
11 PM Mon 45 40 NE 3 2087 4460 0 Blue 0
12 Midnight Tue 44 39 NE 3 2087 4460 0 Blue 0
1 AM Tue 44 39 NE 3 2087 4460 0 Blue 0
2 AM Tue 44 39 NE 3 2087 4460 0 Blue 0
3 AM Tue 44 39 NE 3 2087 4460 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