Detailed Predictions for: Mt Diablo
Launch Altitude (f): 3000
LZ Altitude (f): 1000
Sounding

Station:

KOAK

Date/Time:

25 APR 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 Thu 58 58 SW 7 2628 3000 0 Blue 0
6 AM Thu 57 57 SW 7 2628 3000 0 Blue 0
7 AM Thu 58 58 SW 7 2628 3000 0 Blue 0
8 AM Thu 59 59 W 3 2628 3000 0 Blue 0
9 AM Thu 61 63 W 3 2628 3000 0 Blue 0
10 AM Thu 63 66 W 3 2628 3000 0 Blue 0
11 AM Thu 65 70 SW 6 2628 3000 0 Blue 0
12 Noon Thu 66 72 SW 6 2722 3000 0 Blue 0
1 PM Thu 67 74 SW 6 2983 3000 0 Blue 0
2 PM Thu 70 76 W 12 3322 3000 0 Blue 1
3 PM Thu 70 75 W 12 3114 3000 0 Blue 0
4 PM Thu 71 75 W 12 3114 3000 0 Blue 0
5 PM Thu 70 72 W 13 2722 3000 0 Blue 0
6 PM Thu 69 69 W 13 2628 3000 0 Blue 0
7 PM Thu 67 67 W 13 2628 3000 0 Blue 0
8 PM Thu 64 64 W 12 2628 3000 0 Blue 0
9 PM Thu 65 65 W 12 2628 3000 0 Blue 0
10 PM Thu 64 64 W 12 2628 3000 0 Blue 0
11 PM Thu 64 64 W 10 2628 3000 0 Blue 0
12 Midnight Fri 62 62 W 10 2628 3000 0 Blue 0
1 AM Fri 59 59 W 10 2628 3000 0 Blue 0
2 AM Fri 59 59 W 10 2628 3000 0 Blue 0
3 AM Fri 59 59 W 10 2628 3000 0 Blue 0
4 AM Fri 58 58 W 10 2628 3000 0 Blue 0
5 AM Fri 57 57 W 10 2628 3000 0 Blue 0
6 AM Fri 55 55 W 10 2628 3000 0 Blue 0
7 AM Fri 56 56 W 10 2628 3000 0 Blue 0
8 AM Fri 57 57 W 7 2628 3000 0 Blue 0
9 AM Fri 59 60 W 7 2628 3000 0 Blue 0
10 AM Fri 62 64 W 7 2628 3000 0 Blue 0
11 AM Fri 63 66 NW 3 2628 3000 0 Blue 0
12 Noon Fri 64 68 NW 3 2628 3000 0 Blue 0
1 PM Fri 66 70 NW 3 2628 3000 0 Blue 0
2 PM Fri 69 73 NW 8 2852 3000 0 Blue 0
3 PM Fri 70 73 NW 8 2852 3000 0 Blue 0
4 PM Fri 70 72 NW 8 2722 3000 0 Blue 0
5 PM Fri 70 71 W 12 2628 3000 0 Blue 0
6 PM Fri 68 68 W 12 2628 3000 0 Blue 0
7 PM Fri 66 66 W 12 2628 3000 0 Blue 0
8 PM Fri 63 63 NW 12 2628 3000 0 Blue 0
9 PM Fri 64 64 NW 12 2628 3000 0 Blue 0
10 PM Fri 63 63 NW 12 2628 3000 0 Blue 0
11 PM Fri 63 63 NW 8 2628 3000 0 Blue 0
12 Midnight Sat 61 61 NW 8 2628 3000 0 Blue 0
1 AM Sat 58 58 NW 8 2628 3000 0 Blue 0
2 AM Sat 58 58 N 6 2628 3000 0 Blue 0
3 AM Sat 58 58 N 6 2628 3000 0 Blue 0
4 AM Sat 57 57 N 6 2628 3000 0 Blue 0
5 AM Sat 56 56 N 10 2628 3000 0 Blue 0
6 AM Sat 54 54 N 10 2628 3000 0 Blue 0
7 AM Sat 55 55 N 10 2628 3000 0 Blue 0
8 AM Sat 56 56 N 8 2628 3000 0 Blue 0
9 AM Sat 58 59 N 8 2628 3000 0 Blue 0
10 AM Sat 60 63 N 8 2628 3000 0 Blue 0
11 AM Sat 62 66 N 8 2628 3000 0 Blue 0
12 Noon Sat 63 68 N 8 2628 3000 0 Blue 0
1 PM Sat 65 70 N 8 2628 3000 0 Blue 0
2 PM Sat 67 72 W 9 2722 3000 0 Blue 0
3 PM Sat 68 72 W 9 2722 3000 0 Blue 0
4 PM Sat 68 71 W 9 2628 3000 0 Blue 0
5 PM Sat 68 69 W 10 2628 3000 0 Blue 0
6 PM Sat 67 67 W 10 2628 3000 0 Blue 0
7 PM Sat 65 65 W 10 2628 3000 0 Blue 0
8 PM Sat 62 62 W 8 2628 3000 0 Blue 0
9 PM Sat 62 62 W 8 2628 3000 0 Blue 0
10 PM Sat 62 62 W 8 2628 3000 0 Blue 0
11 PM Sat 61 61 W 8 2628 3000 0 Blue 0
12 Midnight Sun 59 59 W 8 2628 3000 0 Blue 0
1 AM Sun 56 56 W 8 2628 3000 0 Blue 0
2 AM Sun 56 56 SW 8 2628 3000 0 Blue 0
3 AM Sun 56 56 SW 8 2628 3000 0 Blue 0
4 AM Sun 55 55 SW 8 2628 3000 0 Blue 0
5 AM Sun 54 54 SW 9 2628 3000 0 Blue 0
6 AM Sun 52 52 SW 9 2628 3000 0 Blue 0
7 AM Sun 53 53 SW 9 2628 3000 0 Blue 0
8 AM Sun 53 53 SW 9 2628 3000 0 Blue 0
9 AM Sun 55 56 SW 9 2628 3000 0 Blue 0
10 AM Sun 56 59 SW 9 2628 3000 0 Blue 0
11 AM Sun 58 61 SW 16 2628 3000 0 Blue 0
12 Noon Sun 59 63 SW 16 2628 3000 0 Blue 0
1 PM Sun 60 64 SW 16 2628 3000 0 Blue 0
2 PM Sun 62 66 SW 16 2628 3000 0 Blue 0
3 PM Sun 62 65 SW 16 2628 3000 0 Blue 0
4 PM Sun 62 64 SW 16 2628 3000 0 Blue 0
5 PM Sun 62 63 W 18 2628 3000 0 Blue 0
6 PM Sun 61 61 W 18 2628 3000 0 Blue 0
7 PM Sun 60 60 W 18 2628 3000 0 Blue 0
8 PM Sun 57 57 W 18 2628 3000 0 Blue 0
9 PM Sun 57 57 W 18 2628 3000 0 Blue 0
10 PM Sun 57 57 W 18 2628 3000 0 Blue 0
11 PM Sun 56 56 SW 15 2628 3000 0 Blue 0
12 Midnight Mon 55 55 SW 15 2628 3000 0 Blue 0
1 AM Mon 53 53 SW 15 2628 3000 0 Blue 0
2 AM Mon 52 52 SW 15 2628 3000 0 Blue 0
3 AM Mon 52 52 SW 15 2628 3000 0 Blue 0
4 AM Mon 51 51 SW 15 2628 3000 0 Blue 0
5 AM Mon 50 50 SW 15 2628 3000 0 Blue 0
6 AM Mon 49 49 SW 15 2628 3000 0 Blue 0
7 AM Mon 50 50 SW 15 2628 3000 0 Blue 0
8 AM Mon 50 50 SW 15 2628 3000 0 Blue 0
9 AM Mon 52 54 SW 15 2628 3000 0 Blue 0
10 AM Mon 54 57 SW 15 2628 3000 0 Blue 0
11 AM Mon 55 60 SW 18 2628 3000 0 Blue 0
12 Noon Mon 56 62 SW 18 2628 3000 0 Blue 0
1 PM Mon 57 63 SW 18 2628 3000 0 Blue 0
2 PM Mon 58 64 SW 18 2628 3000 0 Blue 0
3 PM Mon 59 64 SW 18 2628 3000 0 Blue 0
4 PM Mon 59 62 SW 18 2628 3000 0 Blue 0
5 PM Mon 59 61 SW 21 2628 3000 0 Blue 0
6 PM Mon 58 58 SW 21 2628 3000 0 Blue 0
7 PM Mon 56 56 SW 21 2628 3000 0 Blue 0
8 PM Mon 54 54 SW 21 2628 3000 0 Blue 0
9 PM Mon 54 54 SW 21 2628 3000 0 Blue 0
10 PM Mon 54 54 SW 21 2628 3000 0 Blue 0
11 PM Mon 53 53 SW 20 2628 3000 0 Blue 0
12 Midnight Tue 52 52 SW 20 2628 3000 0 Blue 0
1 AM Tue 49 49 SW 20 2628 3000 0 Blue 0
2 AM Tue 49 49 SW 20 2628 3000 0 Blue 0
3 AM Tue 49 49 SW 20 2628 3000 0 Blue 0
4 AM Tue 48 48 SW 20 2628 3000 0 Blue 0
5 AM Tue 47 47 SW 20 2628 3000 0 Blue 0
6 AM Tue 46 46 SW 20 2628 3000 0 Blue 0
7 AM Tue 47 47 SW 20 2628 3000 0 Blue 0
8 AM Tue 47 47 SW 20 2628 3000 0 Blue 0
9 AM Tue 49 51 SW 20 2628 3000 0 Blue 0
10 AM Tue 50 53 SW 20 2628 3000 0 Blue 0
11 AM Tue 52 57 W 21 2628 3000 0 Blue 0
12 Noon Tue 52 58 W 21 2628 3000 0 Blue 0
1 PM Tue 54 61 W 21 2628 3000 0 Blue 0
2 PM Tue 56 62 W 21 2628 3000 0 Blue 0
3 PM Tue 56 61 W 21 2628 3000 0 Blue 0
4 PM Tue 56 59 W 21 2628 3000 0 Blue 0
5 PM Tue 56 58 W 21 2628 3000 0 Blue 0
6 PM Tue 55 55 W 21 2628 3000 0 Blue 0
7 PM Tue 54 54 W 21 2628 3000 0 Blue 0
8 PM Tue 52 52 W 21 2628 3000 0 Blue 0
9 PM Tue 52 52 W 21 2628 3000 0 Blue 0
10 PM Tue 52 52 W 21 2628 3000 0 Blue 0
11 PM Tue 51 51 W 18 2628 3000 0 Blue 0
12 Midnight Wed 50 50 W 18 2628 3000 0 Blue 0
1 AM Wed 48 48 W 18 2628 3000 0 Blue 0
2 AM Wed 48 48 W 18 2628 3000 0 Blue 0
3 AM Wed 48 48 W 18 2628 3000 0 Blue 0
4 AM Wed 47 47 W 18 2628 3000 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