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

Station:

KFGZ

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)
6 AM Sun 50 50 W 8 7504 7271 471 Blue 13
7 AM Sun 47 47 NW 8 7272 7225 425 Blue 10
8 AM Sun 41 41 NW 9 7195 7163 363 Blue 4
9 AM Sun 47 48 NW 10 7309 7236 436 Blue 11
10 AM Sun 50 53 N 12 8061 7496 696 Blue 16
11 AM Sun 52 56 N 12 9207 8043 1243 Blue 19
12 Noon Sun 55 59 N 13 10412 9188 2388 Blue 22
1 PM Sun 59 63 N 14 11420 10857 4057 Blue 26
2 PM Sun 60 63 N 14 11420 10857 4057 Blue 26
3 PM Sun 61 63 N 14 11420 10857 4057 Blue 26
4 PM Sun 61 62 N 14 11242 10259 3459 Blue 25
5 PM Sun 61 61 N 13 11064 9548 2748 Blue 24
6 PM Sun 59 59 N 12 10412 9188 2388 Blue 22
7 PM Sun 54 54 N 10 8627 7679 879 Blue 17
8 PM Sun 49 49 N 8 7346 7246 446 Blue 12
9 PM Sun 46 46 NW 8 7246 7215 415 Blue 9
10 PM Sun 45 45 NW 7 7236 7205 405 Blue 8
11 PM Sun 43 43 NW 7 7215 7184 384 Blue 6
12 Midnight Mon 41 41 NW 6 7195 7163 363 Blue 4
1 AM Mon 40 40 NW 5 7184 7153 353 Blue 3
2 AM Mon 39 39 NW 5 7174 7149 349 Blue 2
3 AM Mon 38 38 W 5 7164 7149 349 Blue 1
4 AM Mon 36 36 W 3 0 6800 0 Blue 0
5 AM Mon 35 35 NW 3 0 6800 0 Blue 0
6 AM Mon 34 34 W 3 0 6800 0 Blue 0
7 AM Mon 34 34 W 3 0 6800 0 Blue 0
8 AM Mon 35 35 NW 3 0 6800 0 Blue 0
9 AM Mon 42 43 NW 5 7215 7184 384 Blue 6
10 AM Mon 47 49 N 6 7346 7246 446 Blue 12
11 AM Mon 51 55 N 7 9025 7861 1061 Blue 18
12 Noon Mon 55 59 NE 7 10412 9188 2388 Blue 22
1 PM Mon 58 62 NE 8 11242 10259 3459 Blue 25
2 PM Mon 62 65 NE 9 12341 11212 4412 Blue 28
3 PM Mon 64 66 N 10 12927 11389 4589 Blue 29
4 PM Mon 65 66 N 10 12927 11389 4589 Blue 29
5 PM Mon 64 64 N 9 11644 11035 4235 Blue 27
6 PM Mon 62 62 N 8 11242 10259 3459 Blue 25
7 PM Mon 58 58 N 7 9569 9008 2208 Blue 21
8 PM Mon 55 55 N 5 9025 7861 1061 Blue 18
9 PM Mon 51 51 N 5 7688 7307 507 Blue 14
10 PM Mon 49 49 NW 3 7346 7246 446 Blue 12
11 PM Mon 47 47 NW 5 7272 7225 425 Blue 10
12 Midnight Tue 46 46 NW 5 7246 7215 415 Blue 9
1 AM Tue 45 45 NW 5 7236 7205 405 Blue 8
2 AM Tue 44 44 NW 5 7226 7194 394 Blue 7
3 AM Tue 43 43 NW 5 7215 7184 384 Blue 6
4 AM Tue 41 41 N 5 7195 7163 363 Blue 4
5 AM Tue 39 39 N 5 7174 7149 349 Blue 2
6 AM Tue 38 38 N 5 7164 7149 349 Blue 1
7 AM Tue 39 39 N 6 7174 7149 349 Blue 2
8 AM Tue 42 42 N 5 7205 7174 374 Blue 5
9 AM Tue 45 46 N 5 7246 7215 415 Blue 9
10 AM Tue 50 53 N 5 8061 7496 696 Blue 16
11 AM Tue 54 58 NE 6 9569 9008 2208 Blue 21
12 Noon Tue 59 63 NE 7 11420 10857 4057 Blue 26
1 PM Tue 62 66 E 8 12927 11389 4589 Blue 29
2 PM Tue 65 68 E 8 13546 12177 5377 Blue 31
3 PM Tue 67 69 E 8 13650 12799 5999 Blue 32
4 PM Tue 69 70 E 8 13778 13352 6552 Blue 33
5 PM Tue 69 69 NE 8 13650 12799 5999 Blue 32
6 PM Tue 67 67 NE 8 13442 11595 4795 Blue 30
7 PM Tue 63 63 NE 6 11420 10857 4057 Blue 26
8 PM Tue 57 57 N 3 9388 8582 1782 Blue 20
9 PM Tue 53 53 N 3 8061 7496 696 Blue 16
10 PM Tue 50 50 S 5 7504 7271 471 Blue 13
11 PM Tue 50 50 S 5 7504 7271 471 Blue 13
12 Midnight Wed 49 49 SW 5 7346 7246 446 Blue 12
1 AM Wed 49 49 SW 3 7346 7246 446 Blue 12
2 AM Wed 48 48 W 3 7309 7236 436 Blue 11
3 AM Wed 46 46 W 3 7246 7215 415 Blue 9
4 AM Wed 44 44 NW 3 7226 7194 394 Blue 7
5 AM Wed 42 42 NW 5 7205 7174 374 Blue 5
6 AM Wed 41 41 NW 5 7195 7163 363 Blue 4
7 AM Wed 42 42 NW 5 7205 7174 374 Blue 5
8 AM Wed 45 45 N 5 7236 7205 405 Blue 8
9 AM Wed 49 50 N 5 7504 7271 471 Blue 13
10 AM Wed 54 56 N 6 9207 8043 1243 Blue 19
11 AM Wed 58 61 N 7 11064 9548 2748 Blue 24
12 Noon Wed 62 66 N 8 12927 11389 4589 Blue 29
1 PM Wed 65 69 N 9 13650 12799 5999 Blue 32
2 PM Wed 67 70 N 10 13778 13352 6552 Blue 33
3 PM Wed 69 71 N 10 13989 13520 6720 Blue 34
4 PM Wed 70 71 N 10 13989 13520 6720 Blue 34
5 PM Wed 70 70 N 10 13778 13352 6552 Blue 33
6 PM Wed 68 68 N 10 13546 12177 5377 Blue 31
7 PM Wed 63 63 N 9 11420 10857 4057 Blue 26
8 PM Wed 58 58 N 7 9569 9008 2208 Blue 21
9 PM Wed 54 54 N 6 8627 7679 879 Blue 17
10 PM Wed 52 52 NW 6 7871 7344 544 Blue 15
11 PM Wed 51 51 NW 6 7688 7307 507 Blue 14
12 Midnight Thu 50 50 NW 7 7504 7271 471 Blue 13
1 AM Thu 49 49 NW 7 7346 7246 446 Blue 12
2 AM Thu 48 48 N 7 7309 7236 436 Blue 11
3 AM Thu 46 46 N 7 7246 7215 415 Blue 9
4 AM Thu 43 43 N 8 7215 7184 384 Blue 6
5 AM Thu 41 41 N 9 7195 7163 363 Blue 4
6 AM Thu 40 40 N 10 7184 7153 353 Blue 3
7 AM Thu 40 40 N 10 7184 7153 353 Blue 3
8 AM Thu 41 41 N 10 7195 7163 363 Blue 4
9 AM Thu 43 44 N 10 7226 7194 394 Blue 7
10 AM Thu 46 48 N 12 7309 7236 436 Blue 11
11 AM Thu 49 52 N 13 7871 7344 544 Blue 15
12 Noon Thu 51 55 N 14 9025 7861 1061 Blue 18
1 PM Thu 54 58 N 15 9569 9008 2208 Blue 21
2 PM Thu 57 60 N 16 10885 9368 2568 Blue 23
3 PM Thu 58 60 N 17 10885 9368 2568 Blue 23
4 PM Thu 59 59 N 17 10412 9188 2388 Blue 22
5 PM Thu 58 58 N 17 9569 9008 2208 Blue 21
6 PM Thu 56 56 N 16 9207 8043 1243 Blue 19
7 PM Thu 52 52 N 14 7871 7344 544 Blue 15
8 PM Thu 48 48 N 12 7309 7236 436 Blue 11
9 PM Thu 44 44 N 9 7226 7194 394 Blue 7
10 PM Thu 42 42 N 8 7205 7174 374 Blue 5
11 PM Thu 42 42 N 8 7205 7174 374 Blue 5
12 Midnight Fri 41 41 N 8 7195 7163 363 Blue 4
1 AM Fri 40 40 N 8 7184 7153 353 Blue 3
2 AM Fri 39 39 N 8 7174 7149 349 Blue 2
3 AM Fri 37 37 N 8 7153 7149 349 Blue 0
4 AM Fri 36 36 N 8 0 6800 0 Blue 0
5 AM Fri 34 34 N 7 0 6800 0 Blue 0
6 AM Fri 34 34 N 7 0 6800 0 Blue 0
7 AM Fri 35 35 N 7 0 6800 0 Blue 0
8 AM Fri 37 37 NE 7 7153 7149 349 Blue 0
9 AM Fri 39 40 NE 8 7184 7153 353 Blue 3
10 AM Fri 43 45 NE 9 7236 7205 405 Blue 8
11 AM Fri 46 49 NE 12 7346 7246 446 Blue 12
12 Noon Fri 50 53 NE 13 8061 7496 696 Blue 16
1 PM Fri 53 56 NE 14 9207 8043 1243 Blue 19
2 PM Fri 55 57 E 14 9388 8582 1782 Blue 20
3 PM Fri 57 58 E 13 9569 9008 2208 Blue 21
4 PM Fri 59 59 E 12 10412 9188 2388 Blue 22
5 PM Fri 59 59 E 9 10412 9188 2388 Blue 22
6 PM Fri 57 57 E 8 9388 8582 1782 Blue 20
7 PM Fri 54 54 SE 7 8627 7679 879 Blue 17
8 PM Fri 49 49 S 6 7346 7246 446 Blue 12
9 PM Fri 45 45 SW 5 7236 7205 405 Blue 8
10 PM Fri 43 43 W 5 7215 7184 384 Blue 6
11 PM Fri 43 43 W 5 7215 7184 384 Blue 6
12 Midnight Sat 43 43 W 5 7215 7184 384 Blue 6
1 AM Sat 42 42 W 5 7205 7174 374 Blue 5
2 AM Sat 41 41 SW 3 7195 7163 363 Blue 4
3 AM Sat 39 39 SW 3 7174 7149 349 Blue 2
4 AM Sat 38 38 SW 3 7164 7149 349 Blue 1
5 AM Sat 36 36 SW 5 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 [email protected]