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

Station:

KOAK

Date/Time:

22 MAR 2019

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 Fri 41 36 N 6 1844 4460 0 Blue 0
6 AM Fri 39 34 N 6 1844 4460 0 Blue 0
7 AM Fri 39 34 N 6 1844 4460 0 Blue 0
8 AM Fri 40 35 NE 6 1844 4460 0 Blue 0
9 AM Fri 48 44 NE 6 2481 4460 0 Blue 0
10 AM Fri 53 50 NE 6 4069 4460 0 Blue 6
11 AM Fri 54 51 W 3 4411 4460 0 Blue 7
12 Noon Fri 56 53 W 3 4734 4460 0 Blue 9
1 PM Fri 57 54 W 3 4976 4460 0 Blue 10
2 PM Fri 58 55 W 5 5208 4571 111 Blue 11
3 PM Fri 58 54 W 5 4976 4460 0 Blue 10
4 PM Fri 58 54 W 5 4976 4460 0 Blue 10
5 PM Fri 57 52 W 6 4582 4460 0 Blue 8
6 PM Fri 56 51 W 6 4411 4460 0 Blue 7
7 PM Fri 53 48 W 6 3331 4460 0 Blue 4
8 PM Fri 50 45 NE 7 2730 4460 0 Blue 1
9 PM Fri 49 44 NE 7 2481 4460 0 Blue 0
10 PM Fri 49 44 NE 7 2481 4460 0 Blue 0
11 PM Fri 48 43 NE 5 2107 4460 0 Blue 0
12 Midnight Sat 47 42 NE 5 1844 4460 0 Blue 0
1 AM Sat 47 42 NE 5 1844 4460 0 Blue 0
2 AM Sat 47 42 NE 3 1844 4460 0 Blue 0
3 AM Sat 46 41 NE 3 1844 4460 0 Blue 0
4 AM Sat 46 41 NE 3 1844 4460 0 Blue 0
5 AM Sat 46 41 NE 6 1844 4460 0 Blue 0
6 AM Sat 46 41 NE 6 1844 4460 0 Blue 0
7 AM Sat 46 41 NE 6 1844 4460 0 Blue 0
8 AM Sat 47 42 E 5 1844 4460 0 Blue 0
9 AM Sat 51 46 E 5 2862 4460 0 Blue 2
10 AM Sat 53 48 E 5 3331 4460 0 Blue 4
11 AM Sat 54 49 SW 3 3744 4460 0 Blue 5
12 Noon Sat 55 50 SW 3 4069 4460 0 Blue 6
1 PM Sat 55 50 SW 3 4069 4460 0 Blue 6
2 PM Sat 56 51 SW 6 4411 4460 0 Blue 7
3 PM Sat 56 51 SW 6 4411 4460 0 Blue 7
4 PM Sat 56 51 SW 6 4411 4460 0 Blue 7
5 PM Sat 55 51 N 7 4411 4460 0 Blue 7
6 PM Sat 53 48 N 7 3331 4460 0 Blue 4
7 PM Sat 48 43 N 7 2107 4460 0 Blue 0
8 PM Sat 45 40 N 7 1844 4460 0 Blue 0
9 PM Sat 43 38 N 7 1844 4460 0 Blue 0
10 PM Sat 43 38 N 7 1844 4460 0 Blue 0
11 PM Sat 42 37 NE 6 1844 4460 0 Blue 0
12 Midnight Sun 41 36 NE 6 1844 4460 0 Blue 0
1 AM Sun 41 36 NE 6 1844 4460 0 Blue 0
2 AM Sun 40 35 NE 6 1844 4460 0 Blue 0
3 AM Sun 40 35 NE 6 1844 4460 0 Blue 0
4 AM Sun 39 34 NE 6 1844 4460 0 Blue 0
5 AM Sun 39 34 N 6 1844 4460 0 Blue 0
6 AM Sun 39 34 N 6 1844 4460 0 Blue 0
7 AM Sun 39 34 N 6 1844 4460 0 Blue 0
8 AM Sun 40 35 N 6 1844 4460 0 Blue 0
9 AM Sun 49 45 N 6 2730 4460 0 Blue 1
10 AM Sun 56 54 N 6 4976 4460 0 Blue 10
11 AM Sun 58 57 SW 3 6155 4957 497 Blue 13
12 Noon Sun 59 59 SW 3 6983 5621 1161 Blue 15
1 PM Sun 60 60 SW 3 7620 6096 1636 Blue 16
2 PM Sun 62 62 SW 3 8354 6956 2496 White 18
3 PM Sun 62 61 SW 3 8143 6560 2100 White 17
4 PM Sun 62 59 SW 3 6983 5621 1161 Blue 15
5 PM Sun 61 57 SE 3 6155 4957 497 Blue 13
6 PM Sun 58 53 SE 3 4734 4460 0 Blue 9
7 PM Sun 53 48 SE 3 3331 4460 0 Blue 4
8 PM Sun 50 45 SE 3 2730 4460 0 Blue 1
9 PM Sun 48 43 SE 3 2107 4460 0 Blue 0
10 PM Sun 47 42 SE 3 1844 4460 0 Blue 0
11 PM Sun 46 41 SE 2 1844 4460 0 Blue 0
12 Midnight Mon 45 40 SE 2 1844 4460 0 Blue 0
1 AM Mon 45 40 SE 2 1844 4460 0 Blue 0
2 AM Mon 44 39 SE 2 1844 4460 0 Blue 0
3 AM Mon 44 39 SE 2 1844 4460 0 Blue 0
4 AM Mon 43 38 SE 2 1844 4460 0 Blue 0
5 AM Mon 43 38 E 5 1844 4460 0 Blue 0
6 AM Mon 43 38 E 5 1844 4460 0 Blue 0
7 AM Mon 43 38 E 5 1844 4460 0 Blue 0
8 AM Mon 44 39 E 5 1844 4460 0 Blue 0
9 AM Mon 53 49 E 5 3744 4460 0 Blue 5
10 AM Mon 58 55 E 5 5208 4571 111 Blue 11
11 AM Mon 60 58 S 10 6624 5187 727 Blue 14
12 Noon Mon 61 60 S 10 7620 6096 1636 Blue 16
1 PM Mon 62 61 S 10 8143 6560 2100 White 17
2 PM Mon 64 63 S 10 8564 7547 3087 White 19
3 PM Mon 64 62 S 10 8354 6956 2496 White 18
4 PM Mon 64 61 S 10 8143 6560 2100 White 17
5 PM Mon 63 59 S 6 6983 5621 1161 Blue 15
6 PM Mon 60 55 S 6 5208 4571 111 Blue 11
7 PM Mon 55 50 S 6 4069 4460 0 Blue 6
8 PM Mon 52 47 S 6 2995 4460 0 Blue 3
9 PM Mon 50 45 S 6 2730 4460 0 Blue 1
10 PM Mon 49 44 S 6 2481 4460 0 Blue 0
11 PM Mon 48 43 S 1 2107 4460 0 Blue 0
12 Midnight Tue 47 42 S 1 1844 4460 0 Blue 0
1 AM Tue 47 42 S 1 1844 4460 0 Blue 0
2 AM Tue 46 41 S 1 1844 4460 0 Blue 0
3 AM Tue 46 41 S 1 1844 4460 0 Blue 0
4 AM Tue 45 40 S 1 1844 4460 0 Blue 0
5 AM Tue 45 40 NW 2 1844 4460 0 Blue 0
6 AM Tue 45 40 NW 2 1844 4460 0 Blue 0
7 AM Tue 45 40 NW 2 1844 4460 0 Blue 0
8 AM Tue 46 41 NW 2 1844 4460 0 Blue 0
9 AM Tue 53 49 NW 2 3744 4460 0 Blue 5
10 AM Tue 58 55 NW 2 5208 4571 111 Blue 11
11 AM Tue 60 57 S 10 6155 4957 497 Blue 13
12 Noon Tue 61 58 S 10 6624 5187 727 Blue 14
1 PM Tue 62 59 S 10 6983 5621 1161 Blue 15
2 PM Tue 63 60 S 10 7620 6096 1636 Blue 16
3 PM Tue 63 60 S 10 7620 6096 1636 Blue 16
4 PM Tue 63 59 S 10 6983 5621 1161 Blue 15
5 PM Tue 62 57 S 7 6155 4957 497 Blue 13
6 PM Tue 60 55 S 7 5208 4571 111 Blue 11
7 PM Tue 55 50 S 7 4069 4460 0 Blue 6
8 PM Tue 51 46 S 7 2862 4460 0 Blue 2
9 PM Tue 50 45 S 7 2730 4460 0 Blue 1
10 PM Tue 49 44 S 7 2481 4460 0 Blue 0
11 PM Tue 48 43 S 9 2107 4460 0 Blue 0
12 Midnight Wed 47 42 S 9 1844 4460 0 Blue 0
1 AM Wed 47 42 S 9 1844 4460 0 Blue 0
2 AM Wed 46 41 S 9 1844 4460 0 Blue 0
3 AM Wed 46 41 S 9 1844 4460 0 Blue 0
4 AM Wed 45 40 S 9 1844 4460 0 Blue 0
5 AM Wed 45 40 S 10 1844 4460 0 Blue 0
6 AM Wed 45 40 S 10 1844 4460 0 Blue 0
7 AM Wed 45 40 S 10 1844 4460 0 Blue 0
8 AM Wed 46 41 S 10 1844 4460 0 Blue 0
9 AM Wed 50 45 S 10 2730 4460 0 Blue 1
10 AM Wed 52 47 S 10 2995 4460 0 Blue 3
11 AM Wed 53 48 SW 8 3331 4460 0 Blue 4
12 Noon Wed 54 49 SW 8 3744 4460 0 Blue 5
1 PM Wed 54 49 SW 8 3744 4460 0 Blue 5
2 PM Wed 55 50 SW 8 4069 4460 0 Blue 6
3 PM Wed 55 50 SW 8 4069 4460 0 Blue 6
4 PM Wed 55 50 SW 8 4069 4460 0 Blue 6
5 PM Wed 54 49 SW 16 3744 4460 0 Blue 5
6 PM Wed 52 47 SW 16 2995 4460 0 Blue 3
7 PM Wed 49 44 SW 16 2481 4460 0 Blue 0
8 PM Wed 46 41 SW 16 1844 4460 0 Blue 0
9 PM Wed 45 40 SW 16 1844 4460 0 Blue 0
10 PM Wed 44 39 SW 16 1844 4460 0 Blue 0
11 PM Wed 43 38 W 2 1844 4460 0 Blue 0
12 Midnight Thu 43 38 W 2 1844 4460 0 Blue 0
1 AM Thu 42 37 W 2 1844 4460 0 Blue 0
2 AM Thu 42 37 W 2 1844 4460 0 Blue 0
3 AM Thu 41 36 W 2 1844 4460 0 Blue 0
4 AM Thu 41 36 W 2 1844 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