Detailed Predictions for: Merriam Crater
Launch Altitude (f): 6800
LZ Altitude (f): 6000
Sounding

Station:

KFGZ

Date/Time:

24 AUG 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)
6 AM Sat 64 64 W 6 7331 7296 496 Blue 14
7 AM Sat 67 67 W 5 7368 7331 531 Blue 17
8 AM Sat 72 73 W 5 8950 7968 1168 Blue 23
9 AM Sat 76 79 W 6 12752 9776 2976 Blue 29
10 AM Sat 81 86 W 6 15317 13743 6943 Blue 36
11 AM Sat 85 91 W 6 17692 15964 9164 Blue 40
12 Noon Sat 87 94 W 6 19171 17525 10725 Blue 43
1 PM Sat 89 96 W 6 19648 18497 11697 Blue 45
2 PM Sat 90 96 W 7 19648 18497 11697 Blue 45
3 PM Sat 91 96 W 8 19648 18497 11697 Blue 45
4 PM Sat 91 94 W 10 19171 17525 10725 Blue 43
5 PM Sat 90 91 W 12 17692 15964 9164 Blue 40
6 PM Sat 87 87 W 13 15546 13858 7058 Blue 37
7 PM Sat 83 83 W 13 13772 12954 6154 Blue 33
8 PM Sat 78 78 W 12 11534 9680 2880 Blue 28
9 PM Sat 75 75 W 12 9691 8529 1729 Blue 25
10 PM Sat 73 73 W 12 8950 7968 1168 Blue 23
11 PM Sat 71 71 W 13 8268 7383 583 Blue 21
12 Midnight Sun 70 70 W 13 7985 7368 568 Blue 20
1 AM Sun 69 69 W 13 7700 7353 553 Blue 19
2 AM Sun 68 68 W 12 7384 7342 542 Blue 18
3 AM Sun 67 67 W 10 7368 7331 531 Blue 17
4 AM Sun 66 66 W 9 7354 7319 519 Blue 16
5 AM Sun 65 65 W 9 7342 7308 508 Blue 15
6 AM Sun 64 64 W 9 7331 7296 496 Blue 14
7 AM Sun 67 67 W 8 7368 7331 531 Blue 17
8 AM Sun 72 73 W 7 8950 7968 1168 Blue 23
9 AM Sun 77 80 W 6 13011 9871 3071 Blue 30
10 AM Sun 81 86 W 5 15317 13743 6943 Blue 36
11 AM Sun 85 92 W 5 18206 16647 9847 Blue 41
12 Noon Sun 88 95 NW 6 19445 18002 11202 Blue 44
1 PM Sun 90 97 NW 6 19962 18978 12178 Blue 46
2 PM Sun 91 98 W 7 20380 19336 12536 Blue 47
3 PM Sun 92 97 W 9 19962 18978 12178 Blue 46
4 PM Sun 92 95 W 10 19445 18002 11202 Blue 44
5 PM Sun 91 92 W 13 18206 16647 9847 Blue 41
6 PM Sun 88 88 W 14 16197 14926 8126 Blue 38
7 PM Sun 84 84 W 14 13886 13210 6410 Blue 34
8 PM Sun 79 79 W 14 12752 9776 2976 Blue 29
9 PM Sun 76 76 W 13 9787 8913 2113 Blue 26
10 PM Sun 75 75 W 13 9691 8529 1729 Blue 25
11 PM Sun 73 73 W 14 8950 7968 1168 Blue 23
12 Midnight Mon 72 72 W 14 8550 7686 886 Blue 22
1 AM Mon 71 71 W 14 8268 7383 583 Blue 21
2 AM Mon 70 70 W 13 7985 7368 568 Blue 20
3 AM Mon 69 69 W 12 7700 7353 553 Blue 19
4 AM Mon 68 68 W 12 7384 7342 542 Blue 18
5 AM Mon 67 67 W 10 7368 7331 531 Blue 17
6 AM Mon 66 66 W 9 7354 7319 519 Blue 16
7 AM Mon 69 69 W 8 7700 7353 553 Blue 19
8 AM Mon 74 75 W 6 9691 8529 1729 Blue 25
9 AM Mon 79 82 W 5 13657 12669 5869 Blue 32
10 AM Mon 84 89 NW 5 16883 15248 8448 Blue 38
11 AM Mon 88 95 NW 5 19445 18002 11202 Blue 44
12 Noon Mon 91 98 NW 5 20380 19336 12536 Blue 47
1 PM Mon 93 101 NW 5 21324 20180 13380 Blue 50
2 PM Mon 94 101 NW 3 21324 20180 13380 Blue 50
3 PM Mon 95 100 NW 3 21026 19764 12964 Blue 49
4 PM Mon 95 98 W 6 20380 19336 12536 Blue 47
5 PM Mon 94 95 W 7 19445 18002 11202 Blue 44
6 PM Mon 91 91 W 8 17692 15964 9164 Blue 40
7 PM Mon 86 86 W 9 15317 13743 6943 Blue 36
8 PM Mon 81 81 W 10 13269 11182 4382 Blue 31
9 PM Mon 78 78 W 12 11534 9680 2880 Blue 28
10 PM Mon 76 76 W 13 9787 8913 2113 Blue 26
11 PM Mon 75 75 W 13 9691 8529 1729 Blue 25
12 Midnight Tue 73 73 W 13 8950 7968 1168 Blue 23
1 AM Tue 72 72 W 12 8550 7686 886 Blue 22
2 AM Tue 71 71 W 10 8268 7383 583 Blue 21
3 AM Tue 70 70 W 9 7985 7368 568 Blue 20
4 AM Tue 69 69 W 8 7700 7353 553 Blue 19
5 AM Tue 68 68 W 7 7384 7342 542 Blue 18
6 AM Tue 67 67 W 6 7368 7331 531 Blue 17
7 AM Tue 70 70 W 6 7985 7368 568 Blue 20
8 AM Tue 75 76 W 6 9787 8913 2113 Blue 26
9 AM Tue 80 82 W 6 13657 12669 5869 Blue 32
10 AM Tue 85 89 NW 7 16883 15248 8448 Blue 38
11 AM Tue 89 94 N 9 19171 17525 10725 Blue 43
12 Noon Tue 92 98 N 10 20380 19336 12536 Blue 47
1 PM Tue 94 100 N 10 21026 19764 12964 Blue 49
2 PM Tue 95 100 W 10 21026 19764 12964 Blue 49
3 PM Tue 96 99 W 10 20726 19555 12755 Blue 48
4 PM Tue 96 98 W 10 20380 19336 12536 Blue 47
5 PM Tue 95 96 W 9 19648 18497 11697 Blue 45
6 PM Tue 92 92 W 9 18206 16647 9847 Blue 41
7 PM Tue 87 87 W 9 15546 13858 7058 Blue 37
8 PM Tue 82 82 W 8 13657 12669 5869 Blue 32
9 PM Tue 79 79 W 8 12752 9776 2976 Blue 29
10 PM Tue 77 77 W 9 9883 9318 2518 Blue 27
11 PM Tue 76 76 W 9 9787 8913 2113 Blue 26
12 Midnight Wed 74 74 SW 10 9360 8249 1449 Blue 24
1 AM Wed 73 73 W 10 8950 7968 1168 Blue 23
2 AM Wed 72 72 W 9 8550 7686 886 Blue 22
3 AM Wed 71 71 W 8 8268 7383 583 Blue 21
4 AM Wed 70 70 W 7 7985 7368 568 Blue 20
5 AM Wed 69 69 W 7 7700 7353 553 Blue 19
6 AM Wed 68 68 W 6 7384 7342 542 Blue 18
7 AM Wed 71 71 W 6 8268 7383 583 Blue 21
8 AM Wed 75 76 W 6 9787 8913 2113 Blue 26
9 AM Wed 80 82 W 6 13657 12669 5869 Blue 32
10 AM Wed 84 87 W 7 15546 13858 7058 Blue 37
11 AM Wed 88 92 W 8 18206 16647 9847 Blue 41
12 Noon Wed 90 95 W 10 19445 18002 11202 Blue 44
1 PM Wed 92 96 W 13 19648 18497 11697 Blue 45
2 PM Wed 93 97 W 14 19962 18978 12178 Blue 46
3 PM Wed 94 97 W 15 19962 18978 12178 Blue 46
4 PM Wed 94 95 W 15 19445 18002 11202 Blue 44
5 PM Wed 93 93 W 15 18704 17161 10361 Blue 42
6 PM Wed 90 90 W 15 17298 15475 8675 Blue 39
7 PM Wed 85 85 W 14 15088 13608 6808 Blue 35
8 PM Wed 80 80 W 14 13011 9871 3071 Blue 30
9 PM Wed 77 77 W 13 9883 9318 2518 Blue 27
10 PM Wed 75 75 W 13 9691 8529 1729 Blue 25
11 PM Wed 74 74 W 13 9360 8249 1449 Blue 24
12 Midnight Thu 72 72 W 13 8550 7686 886 Blue 22
1 AM Thu 71 71 W 12 8268 7383 583 Blue 21
2 AM Thu 70 70 W 9 7985 7368 568 Blue 20
3 AM Thu 69 69 W 8 7700 7353 553 Blue 19
4 AM Thu 68 68 W 7 7384 7342 542 Blue 18
5 AM Thu 67 67 W 7 7368 7331 531 Blue 17
6 AM Thu 66 66 W 7 7354 7319 519 Blue 16
7 AM Thu 69 69 W 7 7700 7353 553 Blue 19
8 AM Thu 73 74 W 7 9360 8249 1449 Blue 24
9 AM Thu 78 80 W 7 13011 9871 3071 Blue 30
10 AM Thu 82 85 W 8 15088 13608 6808 Blue 35
11 AM Thu 85 89 W 10 16883 15248 8448 Blue 38
12 Noon Thu 88 92 W 12 18206 16647 9847 Blue 41
1 PM Thu 90 94 W 13 19171 17525 10725 Blue 43
2 PM Thu 90 94 W 13 19171 17525 10725 Blue 43
3 PM Thu 91 94 W 13 19171 17525 10725 Blue 43
4 PM Thu 91 93 W 13 18704 17161 10361 Blue 42
5 PM Thu 90 90 W 13 17298 15475 8675 Blue 39
6 PM Thu 87 87 W 13 15546 13858 7058 Blue 37
7 PM Thu 83 83 W 13 13772 12954 6154 Blue 33
8 PM Thu 78 78 W 12 11534 9680 2880 Blue 28
9 PM Thu 75 75 W 12 9691 8529 1729 Blue 25
10 PM Thu 74 74 W 12 9360 8249 1449 Blue 24
11 PM Thu 72 72 W 12 8550 7686 886 Blue 22
12 Midnight Fri 71 71 W 12 8268 7383 583 Blue 21
1 AM Fri 70 70 W 10 7985 7368 568 Blue 20
2 AM Fri 69 69 W 10 7700 7353 553 Blue 19
3 AM Fri 68 68 W 9 7384 7342 542 Blue 18
4 AM Fri 67 67 W 8 7368 7331 531 Blue 17
5 AM Fri 66 66 W 8 7354 7319 519 Blue 16

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