Detailed Predictions for: La Cumbre Peak
Launch Lat, Long, Altitude (f): 34.4946, -119.713218, 3960
LZ Altitude (f): 695
Sounding

Station:

KVBG

Date/Time:

17 APR 2021

Temp/Wind data from:

NOAA Digital Forecast

Site Forecasts
Time
(Local)
High
Temp

Puddle
Temp

Wind
(mph)
Wind
Gust
Thermal
Ceiling

(ft)
Soaring
Ceiling

(ft)
Above
Launch

(ft)
Thermal
Type
Thermal
Index

(F)
12 Midnight Sat 54 54 SW 6 13 3777 3960 0 Blue 0
1 AM Sat 52 52 ESE 5 12 2539 3960 0 Blue 0
2 AM Sat 50 50 N 5 10 2539 3960 0 Blue 0
3 AM Sat 50 50 N 4 10 2539 3960 0 Blue 0
4 AM Sat 50 50 NNE 4 9 2539 3960 0 Blue 0
5 AM Sat 50 50 NNE 4 8 2539 3960 0 Blue 0
6 AM Sat 55 55 SE 3 6 4477 3960 0 Blue 0
7 AM Sat 59 59 SW 2 4 7485 5340 1380 Blue 3
8 AM Sat 64 65 NNW 1 2 9433 8425 4465 Blue 9
9 AM Sat 67 69 WNW 3 3 10537 9689 5729 Blue 13
10 AM Sat 69 73 W 4 5 13542 10937 6977 White 17
11 AM Sat 72 78 SW 5 6 14557 14557 10597 White 22
12 Noon Sat 72 79 SW 5 6 14759 14759 10799 White 23
1 PM Sat 72 79 SW 6 6 14759 14759 10799 White 23
2 PM Sat 72 78 SW 6 6 14557 14557 10597 White 22
3 PM Sat 72 77 WSW 7 9 14355 14060 10100 White 21
4 PM Sat 72 75 W 9 12 13949 12411 8451 White 19
5 PM Sat 73 75 W 11 14 13949 12411 8451 White 19
6 PM Sat 70 70 WNW 11 16 10994 9998 6038 Blue 14
7 PM Sat 68 68 NW 10 18 10238 9377 5417 Blue 12
8 PM Sat 65 65 NNW 9 20 9433 8425 4465 Blue 9
9 PM Sat 63 63 NNW 8 18 8796 7776 3816 Blue 7
10 PM Sat 60 60 NNW 8 17 7817 6778 2818 Blue 4
11 PM Sat 58 58 N 7 16 7149 4466 506 Blue 2
12 Midnight Sun 57 57 WSW 7 15 6810 3960 0 Blue 1
1 AM Sun 57 57 SE 7 15 6810 3960 0 Blue 1
2 AM Sun 57 57 N 6 14 6810 3960 0 Blue 1
3 AM Sun 57 57 NNE 7 14 6810 3960 0 Blue 1
4 AM Sun 57 57 NNE 7 15 6810 3960 0 Blue 1
5 AM Sun 57 57 NNE 7 15 6810 3960 0 Blue 1
6 AM Sun 60 60 NNE 6 12 7817 6778 2818 Blue 4
7 AM Sun 63 63 NNE 4 10 8796 7776 3816 Blue 7
8 AM Sun 66 67 NNE 3 7 10060 9062 5102 Blue 11
9 AM Sun 70 72 ESE 4 7 12676 10390 6430 Blue 16
10 AM Sun 73 77 S 5 7 14355 14060 10100 White 21
11 AM Sun 77 83 WSW 6 6 15564 15564 11604 White 27
12 Noon Sun 77 84 WSW 6 7 15766 15766 11806 White 28
1 PM Sun 77 85 WSW 7 8 15965 15965 12005 White 29
2 PM Sun 77 84 WSW 8 9 15766 15766 11806 White 28
3 PM Sun 76 82 W 10 13 15365 15365 11405 White 26
4 PM Sun 76 80 W 13 17 14961 14961 11001 White 24
5 PM Sun 75 77 W 15 21 14355 14060 10100 White 21
6 PM Sun 74 74 WNW 13 20 13746 11442 7482 White 18
7 PM Sun 72 72 WNW 11 20 12676 10390 6430 Blue 16
8 PM Sun 70 70 NW 9 19 10994 9998 6038 Blue 14
9 PM Sun 68 68 NW 9 19 10238 9377 5417 Blue 12
10 PM Sun 65 65 NNW 9 19 9433 8425 4465 Blue 9
11 PM Sun 63 63 NNW 9 19 8796 7776 3816 Blue 7
12 Midnight Mon 61 61 NNW 9 19 8147 7114 3154 Blue 5
1 AM Mon 60 60 N 9 19 7817 6778 2818 Blue 4
2 AM Mon 59 59 N 8 18 7485 5340 1380 Blue 3
3 AM Mon 59 59 N 8 17 7485 5340 1380 Blue 3
4 AM Mon 59 59 N 8 16 7485 5340 1380 Blue 3
5 AM Mon 58 58 N 7 15 7149 4466 506 Blue 2
6 AM Mon 62 62 WSW 6 13 8473 7447 3487 Blue 6
7 AM Mon 66 66 SE 5 9 9748 8745 4785 Blue 10
8 AM Mon 70 71 NNE 4 6 11707 10202 6242 Blue 15
9 AM Mon 73 75 E 4 7 13949 12411 8451 White 19
10 AM Mon 76 80 SSE 5 7 14961 14961 11001 White 24
11 AM Mon 80 85 WSW 6 7 15965 15965 12005 White 29
12 Noon Mon 80 86 WSW 7 8 16166 16166 12206 White 30
1 PM Mon 80 86 WSW 7 9 16166 16166 12206 White 30
2 PM Mon 80 85 WSW 8 10 15965 15965 12005 White 29
3 PM Mon 80 84 WSW 9 11 15766 15766 11806 White 28
4 PM Mon 79 81 WSW 9 12 15163 15163 11203 White 25
5 PM Mon 78 79 W 10 13 14759 14759 10799 White 23
6 PM Mon 77 77 WNW 8 13 14355 14060 10100 White 21
7 PM Mon 76 76 NW 7 13 14152 13274 9314 White 20
8 PM Mon 74 74 NW 6 12 13746 11442 7482 White 18
9 PM Mon 73 73 NNW 5 11 13542 10937 6977 White 17
10 PM Mon 72 72 NNW 5 11 12676 10390 6430 Blue 16
11 PM Mon 71 71 NNW 4 10 11707 10202 6242 Blue 15

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 or WeatherAPI.com website.  Puddle temperatures can exceed this temperature. 

Puddle Temp: This estimate is based on the High Temp and the National Weather Service or WeatherAPI.com 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 or WeatherAPI.com website.

Wind Gust: This estimate is taken from the National Weather Service or WeatherAPI.com 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