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

Station:

KFGZ

Date/Time:

18 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)
6 AM Fri 49 49 SW 9 7229 7183 383 Blue 5
7 AM Fri 51 51 SW 8 7353 7213 413 Blue 7
8 AM Fri 48 48 W 7 7214 7168 368 Blue 4
9 AM Fri 53 54 W 7 9687 7345 545 Blue 10
10 AM Fri 56 59 W 9 13267 10615 3815 Blue 15
11 AM Fri 58 62 NW 12 14520 13073 6273 Blue 18
12 Noon Fri 60 64 NW 14 15308 14069 7269 Blue 20
1 PM Fri 63 67 N 15 17281 15169 8369 Blue 23
2 PM Fri 64 67 N 15 17281 15169 8369 Blue 23
3 PM Fri 65 67 N 15 17281 15169 8369 Blue 23
4 PM Fri 66 67 N 13 17281 15169 8369 Blue 23
5 PM Fri 65 65 N 10 15749 14420 7620 Blue 21
6 PM Fri 64 64 N 9 15308 14069 7269 Blue 20
7 PM Fri 59 59 NW 7 13267 10615 3815 Blue 15
8 PM Fri 54 54 NW 5 9687 7345 545 Blue 10
9 PM Fri 51 51 W 3 7353 7213 413 Blue 7
10 PM Fri 49 49 W 3 7229 7183 383 Blue 5
11 PM Fri 47 47 W 3 7199 7153 353 Blue 3
12 Midnight Sat 46 46 W 3 7184 7149 349 Blue 2
1 AM Sat 45 45 W 2 7169 7149 349 Blue 1
2 AM Sat 44 44 W 2 7153 7149 349 Blue 0
3 AM Sat 43 43 W 2 0 6800 0 Blue 0
4 AM Sat 42 42 W 2 0 6800 0 Blue 0
5 AM Sat 39 39 W 2 0 6800 0 Blue 0
6 AM Sat 38 38 W 2 0 6800 0 Blue 0
7 AM Sat 38 38 W 1 0 6800 0 Blue 0
8 AM Sat 39 39 W 1 0 6800 0 Blue 0
9 AM Sat 45 46 W 1 7184 7149 349 Blue 2
10 AM Sat 51 54 W 2 9687 7345 545 Blue 10
11 AM Sat 55 59 SW 2 13267 10615 3815 Blue 15
12 Noon Sat 60 64 S 3 15308 14069 7269 Blue 20
1 PM Sat 64 68 SW 6 18720 15606 8806 Blue 24
2 PM Sat 66 69 SW 7 19440 16706 9906 Blue 25
3 PM Sat 67 69 SW 8 19440 16706 9906 Blue 25
4 PM Sat 68 69 SW 10 19440 16706 9906 Blue 25
5 PM Sat 68 68 SW 10 18720 15606 8806 Blue 24
6 PM Sat 66 66 W 12 17112 14767 7967 Blue 22
7 PM Sat 61 61 W 12 14165 12219 5419 Blue 17
8 PM Sat 56 56 SW 12 10653 8806 2006 Blue 12
9 PM Sat 51 51 SW 12 7353 7213 413 Blue 7
10 PM Sat 49 49 SW 12 7229 7183 383 Blue 5
11 PM Sat 49 49 W 12 7229 7183 383 Blue 5
12 Midnight Sun 49 49 W 12 7229 7183 383 Blue 5
1 AM Sun 48 48 W 10 7214 7168 368 Blue 4
2 AM Sun 47 47 W 9 7199 7153 353 Blue 3
3 AM Sun 45 45 W 8 7169 7149 349 Blue 1
4 AM Sun 43 43 W 7 0 6800 0 Blue 0
5 AM Sun 42 42 W 6 0 6800 0 Blue 0
6 AM Sun 41 41 W 6 0 6800 0 Blue 0
7 AM Sun 41 41 W 6 0 6800 0 Blue 0
8 AM Sun 42 42 NW 7 0 6800 0 Blue 0
9 AM Sun 44 45 NW 8 7169 7149 349 Blue 1
10 AM Sun 47 49 NW 9 7229 7183 383 Blue 5
11 AM Sun 51 54 NW 10 9687 7345 545 Blue 10
12 Noon Sun 55 59 N 12 13267 10615 3815 Blue 15
1 PM Sun 58 62 N 13 14520 13073 6273 Blue 18
2 PM Sun 60 63 NW 13 14869 13713 6913 Blue 19
3 PM Sun 61 63 NW 13 14869 13713 6913 Blue 19
4 PM Sun 62 63 NW 13 14869 13713 6913 Blue 19
5 PM Sun 61 61 NW 13 14165 12219 5419 Blue 17
6 PM Sun 59 59 NW 13 13267 10615 3815 Blue 15
7 PM Sun 56 56 NW 12 10653 8806 2006 Blue 12
8 PM Sun 52 52 NW 10 8003 7228 428 Blue 8
9 PM Sun 48 48 NW 9 7214 7168 368 Blue 4
10 PM Sun 46 46 NW 8 7184 7149 349 Blue 2
11 PM Sun 45 45 NW 7 7169 7149 349 Blue 1
12 Midnight Mon 44 44 NW 6 7153 7149 349 Blue 0
1 AM Mon 43 43 NW 6 0 6800 0 Blue 0
2 AM Mon 41 41 NW 5 0 6800 0 Blue 0
3 AM Mon 39 39 NW 5 0 6800 0 Blue 0
4 AM Mon 37 37 NW 5 0 6800 0 Blue 0
5 AM Mon 36 36 NW 5 0 6800 0 Blue 0
6 AM Mon 35 35 NW 6 0 6800 0 Blue 0
7 AM Mon 36 36 N 6 0 6800 0 Blue 0
8 AM Mon 38 38 N 6 0 6800 0 Blue 0
9 AM Mon 42 43 N 6 0 6800 0 Blue 0
10 AM Mon 45 48 N 6 7214 7168 368 Blue 4
11 AM Mon 49 53 N 6 8880 7243 443 Blue 9
12 Noon Mon 53 57 N 7 11448 9598 2798 Blue 13
1 PM Mon 57 61 N 7 14165 12219 5419 Blue 17
2 PM Mon 60 63 N 7 14869 13713 6913 Blue 19
3 PM Mon 62 64 N 7 15308 14069 7269 Blue 20
4 PM Mon 63 64 N 8 15308 14069 7269 Blue 20
5 PM Mon 63 63 N 8 14869 13713 6913 Blue 19
6 PM Mon 61 61 N 8 14165 12219 5419 Blue 17
7 PM Mon 57 57 N 7 11448 9598 2798 Blue 13
8 PM Mon 53 53 N 6 8880 7243 443 Blue 9
9 PM Mon 49 49 N 5 7229 7183 383 Blue 5
10 PM Mon 47 47 N 5 7199 7153 353 Blue 3
11 PM Mon 46 46 N 6 7184 7149 349 Blue 2
12 Midnight Tue 46 46 N 6 7184 7149 349 Blue 2
1 AM Tue 45 45 N 6 7169 7149 349 Blue 1
2 AM Tue 44 44 N 5 7153 7149 349 Blue 0
3 AM Tue 43 43 N 5 0 6800 0 Blue 0
4 AM Tue 40 40 N 5 0 6800 0 Blue 0
5 AM Tue 39 39 NW 5 0 6800 0 Blue 0
6 AM Tue 38 38 NW 5 0 6800 0 Blue 0
7 AM Tue 39 39 N 5 0 6800 0 Blue 0
8 AM Tue 42 42 N 5 0 6800 0 Blue 0
9 AM Tue 46 47 N 5 7199 7153 353 Blue 3
10 AM Tue 50 53 NE 6 8880 7243 443 Blue 9
11 AM Tue 54 58 NE 7 12406 10332 3532 Blue 14
12 Noon Tue 58 62 E 8 14520 13073 6273 Blue 18
1 PM Tue 61 65 NE 9 15749 14420 7620 Blue 21
2 PM Tue 64 67 NE 9 17281 15169 8369 Blue 23
3 PM Tue 66 68 NE 9 18720 15606 8806 Blue 24
4 PM Tue 67 68 NE 9 18720 15606 8806 Blue 24
5 PM Tue 67 67 N 8 17281 15169 8369 Blue 23
6 PM Tue 65 65 N 8 15749 14420 7620 Blue 21
7 PM Tue 61 61 N 6 14165 12219 5419 Blue 17
8 PM Tue 56 56 N 5 10653 8806 2006 Blue 12
9 PM Tue 52 52 N 3 8003 7228 428 Blue 8
10 PM Tue 50 50 N 3 7244 7198 398 Blue 6
11 PM Tue 49 49 NW 3 7229 7183 383 Blue 5
12 Midnight Wed 48 48 W 3 7214 7168 368 Blue 4
1 AM Wed 47 47 W 3 7199 7153 353 Blue 3
2 AM Wed 46 46 W 2 7184 7149 349 Blue 2
3 AM Wed 44 44 W 2 7153 7149 349 Blue 0
4 AM Wed 43 43 W 2 0 6800 0 Blue 0
5 AM Wed 41 41 S 2 0 6800 0 Blue 0
6 AM Wed 41 41 S 3 0 6800 0 Blue 0
7 AM Wed 42 42 S 3 0 6800 0 Blue 0
8 AM Wed 44 44 S 3 7153 7149 349 Blue 0
9 AM Wed 48 49 S 5 7229 7183 383 Blue 5
10 AM Wed 52 55 SE 6 10398 7948 1148 Blue 11
11 AM Wed 57 61 E 8 14165 12219 5419 Blue 17
12 Noon Wed 61 65 NE 9 15749 14420 7620 Blue 21
1 PM Wed 65 69 NE 10 19440 16706 9906 Blue 25
2 PM Wed 67 70 NE 12 19713 17216 10416 Blue 26
3 PM Wed 69 71 N 13 19867 17690 10890 Blue 27
4 PM Wed 70 71 N 13 19867 17690 10890 Blue 27
5 PM Wed 70 70 NW 13 19713 17216 10416 Blue 26
6 PM Wed 68 68 NW 12 18720 15606 8806 Blue 24
7 PM Wed 64 64 NW 9 15308 14069 7269 Blue 20
8 PM Wed 60 60 W 7 13806 11272 4472 Blue 16
9 PM Wed 56 56 W 5 10653 8806 2006 Blue 12
10 PM Wed 53 53 W 5 8880 7243 443 Blue 9
11 PM Wed 52 52 W 5 8003 7228 428 Blue 8
12 Midnight Thu 51 51 W 6 7353 7213 413 Blue 7
1 AM Thu 50 50 W 5 7244 7198 398 Blue 6
2 AM Thu 48 48 W 5 7214 7168 368 Blue 4
3 AM Thu 47 47 W 5 7199 7153 353 Blue 3
4 AM Thu 45 45 W 5 7169 7149 349 Blue 1
5 AM Thu 43 43 NW 6 0 6800 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