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

Station:

KOAK

Date/Time:

20 OCT 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 Sun 51 46 SE 2 1883 4460 0 Blue 0
6 AM Sun 50 45 E 6 1883 4460 0 Blue 0
7 AM Sun 50 45 SE 5 1883 4460 0 Blue 0
8 AM Sun 52 47 E 3 1883 4460 0 Blue 0
9 AM Sun 57 52 S 1 1883 4460 0 Blue 0
10 AM Sun 63 60 SW 3 3184 4460 0 Blue 2
11 AM Sun 66 64 SW 5 5174 4460 0 Blue 6
12 Noon Sun 68 67 SW 7 6115 5145 685 Blue 9
1 PM Sun 70 69 SW 7 6715 5778 1318 Blue 11
2 PM Sun 71 69 SW 7 6715 5778 1318 Blue 11
3 PM Sun 71 68 W 6 6416 5469 1009 Blue 10
4 PM Sun 71 67 W 6 6115 5145 685 Blue 9
5 PM Sun 69 64 W 6 5174 4460 0 Blue 6
6 PM Sun 66 61 NW 5 3488 4460 0 Blue 3
7 PM Sun 61 56 N 6 1883 4460 0 Blue 0
8 PM Sun 58 53 NE 6 1883 4460 0 Blue 0
9 PM Sun 56 51 E 3 1883 4460 0 Blue 0
10 PM Sun 56 51 SE 7 1883 4460 0 Blue 0
11 PM Sun 56 51 SE 7 1883 4460 0 Blue 0
12 Midnight Mon 56 51 SE 7 1883 4460 0 Blue 0
1 AM Mon 56 51 SE 6 1883 4460 0 Blue 0
2 AM Mon 55 50 E 5 1883 4460 0 Blue 0
3 AM Mon 55 50 E 3 1883 4460 0 Blue 0
4 AM Mon 55 50 SE 3 1883 4460 0 Blue 0
5 AM Mon 54 49 E 3 1883 4460 0 Blue 0
6 AM Mon 53 48 E 3 1883 4460 0 Blue 0
7 AM Mon 53 48 SE 5 1883 4460 0 Blue 0
8 AM Mon 56 51 E 3 1883 4460 0 Blue 0
9 AM Mon 61 56 SE 2 1883 4460 0 Blue 0
10 AM Mon 68 65 S 3 5501 4491 31 Blue 7
11 AM Mon 72 70 SW 3 7153 6079 1619 Blue 12
12 Noon Mon 75 74 SW 3 7811 7291 2831 Blue 16
1 PM Mon 77 76 SW 3 8138 7618 3158 Blue 18
2 PM Mon 77 76 W 5 8138 7618 3158 Blue 18
3 PM Mon 78 76 W 5 8138 7618 3158 Blue 18
4 PM Mon 78 74 W 5 7811 7291 2831 Blue 16
5 PM Mon 76 71 W 2 7318 6377 1917 Blue 13
6 PM Mon 73 68 W 2 6416 5469 1009 Blue 10
7 PM Mon 67 62 W 2 4521 4460 0 Blue 4
8 PM Mon 64 59 NE 5 2878 4460 0 Blue 1
9 PM Mon 63 58 NE 5 2365 4460 0 Blue 0
10 PM Mon 62 57 NE 5 1917 4460 0 Blue 0
11 PM Mon 63 58 NE 5 2365 4460 0 Blue 0
12 Midnight Tue 62 57 NE 5 1917 4460 0 Blue 0
1 AM Tue 62 57 NE 5 1917 4460 0 Blue 0
2 AM Tue 61 56 NE 6 1883 4460 0 Blue 0
3 AM Tue 61 56 NE 6 1883 4460 0 Blue 0
4 AM Tue 61 56 NE 6 1883 4460 0 Blue 0
5 AM Tue 60 55 NE 6 1883 4460 0 Blue 0
6 AM Tue 59 54 NE 6 1883 4460 0 Blue 0
7 AM Tue 59 54 NE 6 1883 4460 0 Blue 0
8 AM Tue 61 56 E 5 1883 4460 0 Blue 0
9 AM Tue 66 61 E 5 3488 4460 0 Blue 3
10 AM Tue 73 70 E 5 7153 6079 1619 Blue 12
11 AM Tue 76 74 SW 3 7811 7291 2831 Blue 16
12 Noon Tue 79 78 SW 3 8854 7944 3484 Blue 20
1 PM Tue 81 80 SW 3 9564 8408 3948 White 22
2 PM Tue 82 81 W 6 9776 8776 4316 White 23
3 PM Tue 82 80 W 6 9564 8408 3948 White 22
4 PM Tue 82 78 W 6 8854 7944 3484 Blue 20
5 PM Tue 80 75 W 5 7974 7455 2995 Blue 17
6 PM Tue 76 71 W 5 7318 6377 1917 Blue 13
7 PM Tue 68 63 W 5 4889 4460 0 Blue 5
8 PM Tue 65 60 NE 5 3184 4460 0 Blue 2
9 PM Tue 63 58 NE 5 2365 4460 0 Blue 0
10 PM Tue 62 57 NE 5 1917 4460 0 Blue 0
11 PM Tue 62 57 NE 5 1917 4460 0 Blue 0
12 Midnight Wed 62 57 NE 5 1917 4460 0 Blue 0
1 AM Wed 62 57 NE 5 1917 4460 0 Blue 0
2 AM Wed 61 56 NE 6 1883 4460 0 Blue 0
3 AM Wed 61 56 NE 6 1883 4460 0 Blue 0
4 AM Wed 61 56 NE 6 1883 4460 0 Blue 0
5 AM Wed 59 54 NE 6 1883 4460 0 Blue 0
6 AM Wed 58 53 NE 6 1883 4460 0 Blue 0
7 AM Wed 58 53 NE 6 1883 4460 0 Blue 0
8 AM Wed 60 55 NE 5 1883 4460 0 Blue 0
9 AM Wed 65 60 NE 5 3184 4460 0 Blue 2
10 AM Wed 71 67 NE 5 6115 5145 685 Blue 9
11 AM Wed 75 73 SW 3 7646 7127 2667 Blue 15
12 Noon Wed 77 75 SW 3 7974 7455 2995 Blue 17
1 PM Wed 79 78 SW 3 8854 7944 3484 Blue 20
2 PM Wed 80 79 SW 6 9221 8107 3647 Blue 21
3 PM Wed 80 78 SW 6 8854 7944 3484 Blue 20
4 PM Wed 80 76 SW 6 8138 7618 3158 Blue 18
5 PM Wed 78 73 W 3 7646 7127 2667 Blue 15
6 PM Wed 74 69 W 3 6715 5778 1318 Blue 11
7 PM Wed 67 62 W 3 4521 4460 0 Blue 4
8 PM Wed 64 59 NE 5 2878 4460 0 Blue 1
9 PM Wed 62 57 NE 5 1917 4460 0 Blue 0
10 PM Wed 62 57 NE 5 1917 4460 0 Blue 0
11 PM Wed 62 57 NE 6 1917 4460 0 Blue 0
12 Midnight Thu 62 57 NE 6 1917 4460 0 Blue 0
1 AM Thu 61 56 NE 6 1883 4460 0 Blue 0
2 AM Thu 61 56 NE 6 1883 4460 0 Blue 0
3 AM Thu 60 55 NE 6 1883 4460 0 Blue 0
4 AM Thu 60 55 NE 6 1883 4460 0 Blue 0
5 AM Thu 59 54 NE 6 1883 4460 0 Blue 0
6 AM Thu 58 53 NE 6 1883 4460 0 Blue 0
7 AM Thu 58 53 NE 6 1883 4460 0 Blue 0
8 AM Thu 60 55 E 6 1883 4460 0 Blue 0
9 AM Thu 65 60 E 6 3184 4460 0 Blue 2
10 AM Thu 72 68 E 6 6416 5469 1009 Blue 10
11 AM Thu 75 72 SW 5 7482 6672 2212 Blue 14
12 Noon Thu 78 75 SW 5 7974 7455 2995 Blue 17
1 PM Thu 80 78 SW 5 8854 7944 3484 Blue 20
2 PM Thu 81 78 W 6 8854 7944 3484 Blue 20
3 PM Thu 81 78 W 6 8854 7944 3484 Blue 20
4 PM Thu 81 77 W 6 8483 7781 3321 Blue 19
5 PM Thu 79 74 W 5 7811 7291 2831 Blue 16
6 PM Thu 75 70 W 5 7153 6079 1619 Blue 12
7 PM Thu 68 63 W 5 4889 4460 0 Blue 5
8 PM Thu 64 59 NE 5 2878 4460 0 Blue 1
9 PM Thu 62 57 NE 5 1917 4460 0 Blue 0
10 PM Thu 62 57 NE 5 1917 4460 0 Blue 0
11 PM Thu 62 57 E 5 1917 4460 0 Blue 0
12 Midnight Fri 62 57 E 5 1917 4460 0 Blue 0
1 AM Fri 62 57 E 5 1917 4460 0 Blue 0
2 AM Fri 61 56 E 6 1883 4460 0 Blue 0
3 AM Fri 61 56 E 6 1883 4460 0 Blue 0
4 AM Fri 61 56 E 6 1883 4460 0 Blue 0
5 AM Fri 59 54 E 6 1883 4460 0 Blue 0
6 AM Fri 58 53 E 6 1883 4460 0 Blue 0
7 AM Fri 58 53 E 6 1883 4460 0 Blue 0
8 AM Fri 60 55 E 3 1883 4460 0 Blue 0
9 AM Fri 65 60 E 3 3184 4460 0 Blue 2
10 AM Fri 71 67 E 3 6115 5145 685 Blue 9
11 AM Fri 75 73 SW 3 7646 7127 2667 Blue 15
12 Noon Fri 77 76 SW 3 8138 7618 3158 Blue 18
1 PM Fri 79 78 SW 3 8854 7944 3484 Blue 20
2 PM Fri 80 78 W 6 8854 7944 3484 Blue 20
3 PM Fri 80 77 W 6 8483 7781 3321 Blue 19
4 PM Fri 80 76 W 6 8138 7618 3158 Blue 18
5 PM Fri 78 73 W 5 7646 7127 2667 Blue 15
6 PM Fri 74 69 W 5 6715 5778 1318 Blue 11
7 PM Fri 66 61 W 5 3488 4460 0 Blue 3
8 PM Fri 63 58 W 5 2365 4460 0 Blue 0
9 PM Fri 61 56 W 5 1883 4460 0 Blue 0
10 PM Fri 60 55 W 5 1883 4460 0 Blue 0
11 PM Fri 60 55 NE 3 1883 4460 0 Blue 0
12 Midnight Sat 60 55 NE 3 1883 4460 0 Blue 0
1 AM Sat 60 55 NE 3 1883 4460 0 Blue 0
2 AM Sat 59 54 NE 5 1883 4460 0 Blue 0
3 AM Sat 59 54 NE 5 1883 4460 0 Blue 0
4 AM Sat 59 54 NE 5 1883 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 [email protected]