249
UXUS97 KGJT 091306
SRGGJT
SOARING FORECAST
NATIONAL WEATHER SERVICE GRAND JUNCTION, COLORADO
706 AM MDT TUESDAY, JUNE 9, 2026
THIS FORECAST IS FOR TUESDAY, JUNE 9, 2026:
IF THE TRIGGER TEMPERATURE OF 67.7 F/19.8 C IS REACHED...THEN
THERMAL SOARING INDEX....................... GOOD
MAXIMUM RATE OF LIFT........................ 1024 FT/MIN (5.2 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 20412 FT MSL (14804 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 91.0 F/33.2 C
TIME OF TRIGGER TEMPERATURE.................... NONE
TIME OF OVERDEVELOPMENT........................ NONE
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... BROKEN/OVERCAST THIN MIDDLE
SURFACE WINDS DURING SOARING WINDOW............ BETWEEN 20 MPH AND 30 MPH
HEIGHT OF THE -3 THERMAL INDEX................. 18174 FT MSL (12566 FT AGL)
THERMAL SOARING OUTLOOK FOR WEDNESDAY 06/10.... EXCELLENT
WAVE SOARING INDEX............................. NOT AVAILABLE
REMARKS...
SUNRISE/SUNSET.................... 05:47:48 / 20:39:09 MDT
TOTAL POSSIBLE SUNSHINE........... 14 HR 51 MIN 21 SEC (891 MIN 21 SEC)
ALTITUDE OF SUN AT 13:13:29 MDT... 73.61 DEGREES
UPPER AIR DATA FROM RAWINSONDE OBSERVATION TAKEN ON 06/09/2026 AT 0600 MDT
FREEZING LEVEL.................. 13271 FT MSL (7663 FT AGL)
CONVECTIVE CONDENSATION LEVEL... 16513 FT MSL (10905 FT AGL)
LIFTED CONDENSATION LEVEL....... 19138 FT MSL (13530 FT AGL)
LIFTED INDEX.................... -0.9
K INDEX......................... +7.3
HEIGHT TEMPERATURE WIND WIND SPD LAPSE RATE CONVECTIONT THERMAL LIFT RATE
FT MSL DEG C DEG F DIR KT M/S C/KM F/KFT DEG C DEG F INDEX FPM M/S
--------------------------------------------------------------------------------
50000 -58.5 -73.3 260 40 20 4.3 2.3 M M M M M
45000 -53.3 -63.9 270 54 28 0.3 0.1 M M M M M
40000 -52.8 -63.0 270 72 37 3.5 1.9 M M M M M
38000 -50.0 -58.0 280 74 38 4.7 2.6 M M M M M
36000 -47.2 -53.0 285 77 39 4.7 2.6 M M M M M
34000 -43.4 -46.1 285 78 40 7.3 4.0 M M M M M
32000 -39.0 -38.2 290 77 40 7.3 4.0 M M M M M
30000 -33.4 -28.1 285 77 40 8.9 4.9 41.6 106.9 6.7 M M
29000 -30.7 -23.3 285 78 40 8.9 4.9 41.3 106.3 6.5 M M
28000 -28.1 -18.6 285 78 40 9.1 5.0 41.1 106.0 6.5 M M
27000 -25.6 -14.1 285 77 40 7.9 4.3 40.4 104.8 6.0 M M
26000 -23.3 -9.9 285 75 39 7.9 4.3 39.7 103.5 5.5 M M
25000 -20.9 -5.6 285 74 38 7.9 4.3 39.1 102.4 5.0 M M
24000 -18.8 -1.8 285 71 37 6.0 3.3 38.1 100.6 4.3 M M
23000 -17.0 1.4 285 68 35 6.0 3.3 36.7 98.0 3.1 M M
22000 -15.3 4.5 285 64 33 6.0 3.3 35.4 95.7 2.1 M M
21000 -13.6 7.5 280 62 32 5.5 3.0 34.0 93.1 0.9 M M
20000 -11.9 10.6 280 60 31 5.6 3.0 32.4 90.4 -0.4 1199 6.1
19500 -11.1 12.0 275 60 31 5.6 3.1 31.7 89.1 -1.1 1159 5.9
19000 -10.3 13.5 275 59 30 5.6 3.1 31.1 87.9 -1.7 1120 5.7
18500 -9.5 14.9 275 57 30 5.0 2.7 30.3 86.5 -2.4 1082 5.5
18000 -8.4 16.9 275 55 28 5.0 2.8 29.1 84.3 -3.4 1026 5.2
17500 -7.6 18.3 275 53 27 5.0 2.7 28.3 82.9 -4.1 989 5.0
17000 -6.9 19.6 275 50 26 4.9 2.7 27.5 81.4 -4.9 952 4.8
16500 -6.1 21.0 270 48 25 5.4 3.0 26.7 80.0 -5.6 914 4.6
16000 -5.3 22.5 270 45 23 5.6 3.1 26.0 78.7 -6.3 876 4.4
15500 -4.5 23.9 270 43 22 5.9 3.2 25.3 77.5 -7.0 837 4.3
15000 -3.6 25.5 270 40 21 6.7 3.7 24.7 76.5 -7.6 795 4.0
14500 -2.7 27.1 270 38 19 6.7 3.7 24.2 75.6 -8.1 751 3.8
14000 -1.6 29.1 270 35 18 8.1 4.4 23.8 74.9 -8.6 705 3.6
13500 -0.5 31.1 265 33 17 8.0 4.4 23.6 74.4 -8.9 655 3.3
13000 0.7 33.3 265 30 16 8.0 4.4 23.3 73.9 -9.3 606 3.1
12500 1.9 35.4 265 28 15 8.0 4.4 23.0 73.4 -9.6 556 2.8
12000 3.0 37.4 260 26 13 7.8 4.3 22.7 72.9 -10.0 507 2.6
11500 4.1 39.4 260 24 12 7.9 4.3 22.4 72.3 -10.4 459 2.3
11000 5.2 41.4 260 21 11 6.5 3.6 22.0 71.6 -10.8 412 2.1
10500 6.1 43.0 260 17 9 7.4 4.1 21.5 70.6 -11.4 370 1.9
10250 6.7 44.1 260 16 8 8.1 4.5 21.4 70.4 -11.6 345 1.8
10000 7.2 45.0 260 15 8 6.2 3.4 21.1 70.1 -11.8 322 1.6
9750 7.6 45.7 265 14 7 5.7 3.2 20.8 69.5 -12.2 302 1.5
9500 8.1 46.6 265 12 6 6.1 3.3 20.5 69.0 -12.5 282 1.4
9250 8.5 47.3 270 11 6 7.8 4.3 20.3 68.6 -12.8 261 1.3
9000 9.2 48.6 275 11 6 8.4 4.6 20.2 68.4 -12.9 235 1.2
8750 9.7 49.5 280 10 5 7.8 4.3 20.1 68.1 -13.1 210 1.1
8500 10.3 50.5 285 10 5 8.1 4.5 19.9 67.9 -13.3 185 0.9
8250 10.9 51.6 295 9 5 7.3 4.0 19.8 67.6 -13.5 160 0.8
8000 11.4 52.5 295 9 5 7.0 3.9 19.6 67.2 -13.7 137 0.7
7750 12.0 53.6 300 9 4 7.6 4.2 19.4 66.9 -13.9 113 0.6
7500 12.5 54.5 305 8 4 7.5 4.1 19.2 66.6 -14.1 89 0.5
7250 13.1 55.6 305 8 4 7.6 4.2 19.1 66.3 -14.3 64 0.3
7000 13.7 56.7 305 7 4 6.4 3.5 18.9 66.0 -14.5 41 0.2
6750 14.1 57.4 305 6 3 6.2 3.4 18.6 65.4 -14.9 20 0.1
6500 14.5 58.1 305 5 2 4.3 2.3 18.3 64.9 -15.2 M M
6250 14.7 58.5 305 3 1 -0.6 -0.3 17.7 63.8 -15.8 M M
6000 14.7 58.5 310 1 0 2.8 1.5 16.9 62.5 -16.5 M M
5750 14.8 58.6 000 0 0 -4.4 -2.4 16.4 61.4 -17.2 M M
5500 M M M M M M M M M M M M
5250 M M M M M M M M M M M M
5000 M M M M M M M M M M M M
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *
06/09/2026 AT 0900 MDT | 06/09/2026 AT 1200 MDT
|
CAPE... 0.0 LI... +3.2 | CAPE... +1.3 LI... +2.0
CINH... -0.3 K INDEX... +6.3 | CINH... -3.2 K INDEX... +12.9
|
HEIGHT TEMPERATURE WND WNDSPD LAPSE RATE | TEMPERATURE WND WNDSPD LAPSE RATE
FT MSL DEG C DEG F DIR KT M/S C/KM F/KFT | DEG C DEG F DIR KT M/S C/KM F/KFT
--------------------------------------------------------------------------------
50000 -58.6 -73.5 245 37 19 0.4 0.2 | -58.6 -73.5 250 39 20 0.2 0.1
45000 -57.4 -71.3 250 43 22 2.7 1.5 | -57.1 -70.8 250 51 26 4.0 2.2
40000 -53.0 -63.4 260 55 28 5.5 3.0 | -50.8 -59.4 250 64 33 4.1 2.2
38000 -49.5 -57.1 260 55 29 5.7 3.1 | -48.3 -54.9 250 67 34 4.1 2.2
36000 -46.1 -51.0 260 56 29 5.7 3.1 | -45.9 -50.6 245 69 36 4.1 2.2
34000 -42.5 -44.5 250 56 29 6.2 3.4 | -42.6 -44.7 245 68 35 6.2 3.4
32000 -38.8 -37.8 240 56 29 6.1 3.4 | -38.9 -38.0 245 64 33 6.1 3.4
30000 -34.9 -30.8 240 57 29 7.0 3.8 | -34.7 -30.5 240 62 32 7.6 4.2
29000 -32.8 -27.0 240 56 29 7.0 3.8 | -32.5 -26.5 240 60 31 7.6 4.2
28000 -30.7 -23.3 235 56 29 7.0 3.8 | -30.2 -22.4 240 59 30 7.7 4.2
27000 -28.8 -19.8 235 56 29 6.1 3.3 | -28.0 -18.4 235 59 30 7.4 4.1
26000 -27.0 -16.6 230 57 29 6.1 3.3 | -25.2 -13.4 235 59 31 7.4 4.1
25000 -25.2 -13.4 230 57 29 6.1 3.3 | -23.0 -9.4 235 60 31 7.5 4.1
24000 -22.6 -8.7 225 58 30 7.6 4.2 | -21.2 -6.2 230 60 31 5.0 2.8
23000 -20.3 -4.5 225 57 30 7.7 4.2 | -19.7 -3.5 230 59 31 5.0 2.7
22000 -18.0 -0.4 225 57 30 7.6 4.2 | -18.2 -0.8 225 59 30 4.8 2.6
21000 -15.6 3.9 225 56 29 8.1 4.5 | -16.1 3.0 225 57 29 7.8 4.3
20000 -13.2 8.2 225 54 28 8.1 4.5 | -13.8 7.2 225 54 28 7.8 4.3
19500 -11.9 10.6 225 53 27 8.1 4.5 | -12.6 9.3 230 53 27 7.8 4.3
19000 -10.7 12.7 225 52 27 7.7 4.2 | -11.4 11.5 230 51 26 7.2 3.9
18500 -9.6 14.7 230 51 26 7.5 4.1 | -10.4 13.3 230 49 25 6.8 3.7
18000 -8.5 16.7 230 49 25 7.5 4.1 | -9.4 15.1 230 47 24 6.8 3.7
17500 -7.4 18.7 230 48 25 7.0 3.9 | -8.4 16.9 230 44 23 7.1 3.9
17000 -6.4 20.5 230 46 24 7.1 3.9 | -7.4 18.7 230 42 22 7.0 3.9
16500 -5.3 22.5 230 44 23 7.0 3.8 | -6.3 20.7 225 40 20 7.7 4.2
16000 -4.3 24.3 230 42 22 7.0 3.8 | -5.2 22.6 225 38 19 8.0 4.4
15500 -3.3 26.1 225 40 21 7.1 3.9 | -4.0 24.8 225 35 18 8.3 4.5
15000 -2.2 28.0 225 39 20 7.5 4.1 | -2.7 27.1 225 34 17 8.8 4.8
14500 -1.1 30.0 225 37 19 7.5 4.1 | -1.4 29.5 225 32 16 8.8 4.8
14000 0.0 32.0 225 36 19 8.0 4.4 | -0.1 31.8 225 31 16 9.2 5.0
13500 1.2 34.2 225 35 18 8.0 4.4 | 1.3 34.3 225 30 15 9.1 5.0
13000 2.3 36.1 225 33 17 8.1 4.4 | 2.6 36.7 225 29 15 9.3 5.1
12500 3.5 38.3 225 32 17 8.1 4.4 | 4.0 39.2 225 28 14 9.3 5.1
12000 4.7 40.5 220 31 16 8.4 4.6 | 5.4 41.7 225 27 14 9.4 5.2
11500 6.0 42.8 220 29 15 8.5 4.7 | 6.8 44.2 225 26 14 9.5 5.2
11000 7.2 45.0 220 27 14 7.4 4.1 | 8.2 46.8 230 25 13 8.4 4.6
10500 8.3 46.9 220 25 13 6.5 3.6 | 9.4 48.9 230 24 12 8.0 4.4
10250 8.8 47.8 220 24 13 10.4 5.7 | 10.1 50.2 230 24 12 12.1 6.6
10000 9.8 49.6 215 24 12 11.3 6.2 | 11.1 52.0 230 25 13 12.1 6.6
9750 10.4 50.7 215 24 12 8.0 4.4 | 11.8 53.2 230 24 13 8.9 4.9
9500 11.1 52.0 215 23 12 9.1 5.0 | 12.6 54.7 230 24 12 9.8 5.4
9250 11.7 53.1 215 23 12 8.0 4.4 | 13.3 55.9 230 24 12 9.4 5.2
9000 12.3 54.1 215 21 11 8.0 4.4 | 14.7 58.5 235 23 12 10.0 5.5
8750 12.9 55.2 215 21 11 8.7 4.8 | 15.5 59.9 235 23 12 10.0 5.5
8500 14.2 57.6 215 20 10 8.6 4.7 | 16.2 61.2 235 23 12 9.8 5.4
8250 14.9 58.8 215 18 9 8.7 4.8 | 16.9 62.4 235 22 11 9.9 5.4
8000 15.5 59.9 215 18 9 8.6 4.7 | 17.7 63.9 235 22 11 10.2 5.6
7750 16.2 61.2 210 17 9 8.8 4.8 | 18.5 65.3 235 22 11 10.5 5.7
7500 16.8 62.2 210 17 9 7.1 3.9 | 19.2 66.6 235 22 11 9.3 5.1
7250 17.3 63.1 210 16 8 6.3 3.5 | 19.9 67.8 235 21 11 8.8 4.8
7000 17.8 64.0 205 15 8 8.9 4.9 | 20.6 69.1 240 21 11 10.7 5.9
6750 18.6 65.5 205 15 8 10.2 5.6 | 21.5 70.7 235 20 10 11.5 6.3
6500 19.3 66.7 200 14 7 10.0 5.5 | 22.3 72.1 235 20 10 11.2 6.1
6250 20.1 68.2 200 13 7 10.8 5.9 | 23.1 73.6 240 19 10 12.0 6.6
6000 20.8 69.4 200 13 6 7.6 4.2 | 24.0 75.2 240 19 10 7.9 4.3
5750 21.3 70.3 200 12 6 9.3 5.1 | 24.5 76.1 240 18 9 12.4 6.8
5500 23.5 74.3 195 10 5 63.7 35.0 | 27.7 81.9 240 16 8 94.8 52.0
5250 M M M M M M M | M M M M M M M
5000 M M M M M M M | M M M M M M M
06/09/2026 AT 1500 MDT | 06/09/2026 AT 1800 MDT
|
CAPE... +1.7 LI... +0.7 | CAPE... +4.1 LI... +1.1
CINH... -2.5 K INDEX... +9.6 | CINH... -0.3 K INDEX... +14.5
|
HEIGHT TEMPERATURE WND WNDSPD LAPSE RATE | TEMPERATURE WND WNDSPD LAPSE RATE
FT MSL DEG C DEG F DIR KT M/S C/KM F/KFT | DEG C DEG F DIR KT M/S C/KM F/KFT
--------------------------------------------------------------------------------
50000 -58.2 -72.8 255 43 22 0.7 0.4 | -58.2 -72.8 250 40 20 1.8 1.0
45000 -55.8 -68.4 250 60 31 4.1 2.2 | -54.5 -66.1 255 59 30 4.1 2.2
40000 -49.7 -57.5 250 70 36 4.3 2.4 | -48.4 -55.1 255 75 39 4.1 2.2
38000 -47.1 -52.8 245 72 37 4.3 2.4 | -46.0 -50.8 250 74 38 4.0 2.2
36000 -44.4 -47.9 240 75 39 4.4 2.4 | -43.6 -46.5 250 72 37 4.0 2.2
34000 -41.9 -43.4 240 75 39 4.2 2.3 | -41.2 -42.2 245 70 36 3.2 1.8
32000 -39.3 -38.7 240 72 37 4.2 2.3 | -39.2 -38.6 245 69 35 3.2 1.8
30000 -35.7 -32.3 240 68 35 7.3 4.0 | -36.3 -33.3 245 65 33 6.2 3.4
29000 -33.5 -28.3 240 65 33 7.4 4.0 | -34.4 -29.9 245 62 32 6.2 3.4
28000 -31.3 -24.3 240 61 32 7.4 4.0 | -32.5 -26.5 245 59 30 6.2 3.4
27000 -28.3 -18.9 240 60 31 8.4 4.6 | -30.3 -22.5 245 57 29 8.5 4.7
26000 -25.9 -14.6 240 59 30 8.5 4.6 | -27.7 -17.9 245 55 28 8.5 4.7
25000 -23.4 -10.1 240 59 30 8.6 4.7 | -25.2 -13.4 245 53 27 8.5 4.7
24000 -21.3 -6.3 235 58 30 6.2 3.4 | -22.8 -9.0 245 51 26 7.5 4.1
23000 -19.4 -2.9 235 58 30 6.2 3.4 | -20.5 -4.9 245 49 25 7.6 4.2
22000 -17.6 0.3 235 57 29 6.2 3.4 | -17.7 0.1 250 46 24 7.7 4.2
21000 -15.7 3.7 230 54 28 6.2 3.4 | -15.6 3.9 245 44 23 7.5 4.1
20000 -13.9 7.0 230 49 25 6.2 3.4 | -13.4 7.9 245 41 21 7.5 4.1
19500 -12.9 8.8 230 47 24 6.3 3.4 | -12.3 9.9 240 40 21 7.6 4.2
19000 -12.0 10.4 225 45 23 7.5 4.1 | -11.2 11.8 240 39 20 7.8 4.3
18500 -10.7 12.7 225 43 22 8.4 4.6 | -10.0 14.0 240 38 20 7.8 4.3
18000 -9.4 15.1 225 41 21 8.5 4.7 | -8.9 16.0 235 37 19 7.9 4.3
17500 -8.1 17.4 220 39 20 9.1 5.0 | -7.6 18.3 235 36 19 9.0 4.9
17000 -6.8 19.8 220 38 19 9.0 4.9 | -6.3 20.7 235 36 18 8.9 4.9
16500 -5.4 22.3 220 37 19 9.1 5.0 | -4.9 23.2 235 35 18 9.3 5.1
16000 -4.1 24.6 220 36 18 9.1 5.0 | -3.5 25.7 235 35 18 9.5 5.2
15500 -2.7 27.1 220 35 18 9.2 5.0 | -2.1 28.2 235 35 18 9.4 5.1
15000 -1.3 29.7 220 34 18 9.5 5.2 | -0.7 30.7 235 34 18 9.2 5.0
14500 0.1 32.2 220 34 17 9.5 5.2 | 0.7 33.3 235 34 17 9.2 5.0
14000 1.5 34.7 225 33 17 9.3 5.1 | 2.1 35.8 235 33 17 9.3 5.1
13500 2.9 37.2 225 33 17 9.3 5.1 | 3.5 38.3 235 33 17 9.2 5.1
13000 4.3 39.7 225 32 16 9.4 5.1 | 4.9 40.8 235 32 17 9.5 5.2
12500 5.7 42.3 225 31 16 9.4 5.1 | 6.3 43.3 235 32 16 9.5 5.2
12000 7.1 44.8 225 30 16 9.4 5.1 | 7.7 45.9 235 31 16 9.5 5.2
11500 8.5 47.3 230 30 15 9.4 5.2 | 9.1 48.4 240 31 16 9.5 5.2
11000 9.9 49.8 230 29 15 8.6 4.7 | 10.5 50.9 240 30 15 8.3 4.6
10500 11.1 52.0 235 28 14 8.6 4.7 | 11.6 52.9 240 29 15 8.5 4.7
10250 11.9 53.4 235 28 14 11.8 6.4 | 12.4 54.3 240 29 15 12.3 6.7
10000 12.8 55.0 235 28 14 11.2 6.2 | 13.4 56.1 240 28 15 11.2 6.1
9750 13.5 56.3 235 27 14 8.9 4.9 | 14.0 57.2 240 28 14 8.8 4.8
9500 14.9 58.8 240 27 14 10.2 5.6 | 14.7 58.5 240 28 14 9.1 5.0
9250 15.7 60.3 240 27 14 10.6 5.8 | 15.4 59.7 240 27 14 10.2 5.6
9000 16.5 61.7 240 26 14 9.7 5.3 | 16.2 61.2 240 27 14 10.7 5.9
8750 17.2 63.0 240 26 13 10.0 5.5 | 17.0 62.6 240 26 14 9.6 5.3
8500 17.9 64.2 240 26 13 9.5 5.2 | 18.4 65.1 240 26 13 9.6 5.3
8250 18.6 65.5 245 26 13 9.7 5.3 | 19.1 66.4 245 26 13 9.6 5.3
8000 19.4 66.9 245 25 13 10.2 5.6 | 19.9 67.8 245 25 13 9.8 5.4
7750 20.2 68.4 245 25 13 10.4 5.7 | 20.6 69.1 245 24 13 10.0 5.5
7500 20.9 69.6 245 24 12 9.3 5.1 | 21.3 70.3 245 24 12 9.2 5.0
7250 21.6 70.9 245 25 13 8.6 4.7 | 22.0 71.6 245 24 12 8.6 4.7
7000 22.3 72.1 250 24 13 10.5 5.7 | 22.7 72.9 245 24 12 10.1 5.5
6750 23.1 73.6 250 23 12 11.3 6.2 | 23.5 74.3 245 23 12 10.7 5.9
6500 23.9 75.0 250 22 11 10.8 6.2 | 24.3 75.7 245 21 11 10.6 5.8
6250 24.8 76.6 250 22 11 11.4 6.3 | 25.1 77.2 245 21 11 11.3 6.2
6000 25.6 78.1 250 22 11 8.3 4.6 | 25.9 78.6 245 21 11 8.7 4.8
5750 26.2 79.2 250 20 10 13.3 7.3 | 26.5 79.7 245 19 10 10.5 5.8
5500 29.2 84.6 255 18 9 84.7 46.5 | 28.4 83.1 245 16 8 54.6 30.0
5250 M M M M M M M | M M M M M M M
5000 M M M M M M M | M M M M M M M
________________________________________________________________________________
THIS PRODUCT IS ISSUED TWICE PER DAY, ONCE BY APPROXIMATELY 0630 MST/0730 MDT
(1330 UTC) AND AGAIN BY APPROXIMATELY 1830 MST/1930 MDT (0130 UTC). IT IS NOT
CONTINUOUSLY MONITORED NOR UPDATED AFTER ITS INITIAL ISSUANCE.
THE INFORMATION CONTAINED HEREIN IS BASED ON RAWINSONDE OBSERVATION AND/OR
NUMERICAL WEATHER PREDICTION MODEL DATA TAKEN AT WALKER FIELD IN GRAND
JUNCTION, COLORADO AT
NORTH LATITUDE: 39 DEG 07 MIN 00.001 SEC
WEST LONGITUDE: 108 DEG 31 MIN 59.998 SEC
ELEVATION: 4839 FEET (1475 METERS)
AND MAY NOT BE REPRESENTATIVE OF OTHER AREAS ALONG THE WESTERN SLOPE OF
COLORADO. NOTE THAT SOME ELEVATIONS IN NUMERICAL WEATHER PREDICTION MODELS
DIFFER FROM ACTUAL STATION ELEVATIONS, WHICH CAN LEAD TO DATA WHICH APPEAR
TO BE BELOW GROUND. ERRONEOUS DATA SUCH AS THESE SHOULD NOT BE USED.
THE CONTENT AND FORMAT OF THIS REPORT AS WELL AS THE ISSUANCE TIMES ARE SUBJECT
TO CHANGE WITHOUT PRIOR NOTICE. COMMENTS AND SUGGESTIONS ARE WELCOME AND SHOULD
BE DIRECTED TO ONE OF THE ADDRESSES OR PHONE NUMBERS SHOWN AT THE BOTTOM OF THIS
PAGE. TO EXPEDITE A RESPONSE TO COMMENTS, BE SURE TO MENTION YOUR INTEREST IN
THE SOARING FORECAST.
DEFINITIONS:
CAPE (CONVECTIVE AVAILABLE POTENTIAL ENERGY) - AN INTEGRATED MEASURE OF THE
ENERGY AVAILABLE FOR CONVECTIVE DEVELOPMENT, ALSO KNOWN AS THE POSITIVE
AREA ON A THERMODYNAMIC DIAGRAM. UNITS ARE JOULES PER KILOGRAM. LARGER
VALUES ARE INDICATIVE OF GREATER INSTABILITY AND THE POSSIBILITY OF
STRONGER CONVECTIVE ACTIVITY, INCLUDING THUNDERSTORMS. VALUES AROUND OR
GREATER THAN 1000 SUGGEST THE POSSIBILITY OF SEVERE WEATHER SHOULD
CONVECTIVE ACTIVITY DEVELOP.
CINH (CONVECTIVE INHIBITION) - AN INTEGRATED MEASURE OF THE AMOUNT OF ENERGY
NEEDED TO INITIATE CONVECTIVE ACTIVITY, ALSO KNOWN AS THE NEGATIVE AREA ON
A THERMODYNAMIC DIAGRAM. UNITS ARE JOULES PER KILOGRAM. THE MORE NEGATIVE
THIS NUMBER, THE MORE ENERGY IS REQUIRED TO INITIATE CONVECTION. THIS
INHIBITIVE ENERGY CAN BE OVERCOME THROUGH SURFACE HEATING, COOLING ALOFT,
LIFTING MECHANISMS (OROGRAPHIC, FRONTAL, GRAVITY WAVES, ETC.)
CONVECTIVE CONDENSATION LEVEL - THE HEIGHT TO WHICH AN AIR PARCEL POSSESSING THE
AVERAGE SATURATION MIXING RATIO IN THE LOWEST 4000 FEET OF THE AIRMASS,
IF HEATED SUFFICIENTLY FROM BELOW, WILL RISE DRY ADIABATICALLY UNTIL IT
JUST BECOMES SATURATED. IT ESTIMATES THE BASE OF CUMULUS CLOUDS THAT ARE
PRODUCED BY SURFACE HEATING ONLY.
CONVECTION TEMPERATURE (CONVECTIONT) - THE SURFACE TEMPERATURE REQUIRED TO MAKE
THE AIRMASS DRY ADIABATIC UP TO THE GIVEN LEVEL. IT CAN BE CONSIDERED A
"TRIGGER TEMPERATURE" FOR THAT LEVEL.
FREEZING LEVEL - THE HEIGHT WHERE THE TEMPERATURE IS ZERO DEGREES CELSIUS.
HEIGHT OF STABLE LAYER - THE HEIGHT (BETWEEN 12,000 AND 18,000 FEET ABOVE
MEAN SEA LEVEL) WHERE THE SMALLEST LAPSE RATE EXISTS. THE LOCATION AND
EXISTENCE OF THIS FEATURE IS IMPORTANT IN THE GENERATION OF MOUNTAIN
WAVES.
K INDEX - A MEASURE OF STABILITY WHICH COMBINES THE TEMPERATURE DIFFERENCE
BETWEEN APPROXIMATELY 5,000 AND 18,000 FEET ABOVE THE SURFACE, THE AMOUNT
OF MOISTURE AT APPROXIMATELY 5,000 FEET ABOVE THE SURFACE, AND A MEASURE
OF THE DRYNESS AT APPROXIMATELY 10,000 FEET ABOVE THE SURFACE. LARGER
POSITIVE NUMBERS INDICATE MORE INSTABILITY AND A GREATER LIKELIHOOD OF
THUNDERSTORM DEVELOPMENT. ONE INTERPRETATION OF K INDEX VALUES REGARDING
SOARING IN THE WESTERN UNITED STATES IS GIVEN IN WMO TECHNICAL NOTE 158
AND IS REPRODUCED IN THE FOLLOWING TABLE:
BELOW -10 NO OR WEAK THERMALS
-10 TO 5 DRY THERMALS OR 1/8 CUMULUS WITH MODERATE THERMALS
5 TO 15 GOOD SOARING CONDITIONS
15 TO 20 GOOD SOARING CONDITIONS WITH OCCASIONAL SHOWERS
20 TO 30 EXCELLENT SOARING CONDITIONS, BUT INCREASING
PROBABILITY OF SHOWERS AND THUNDERSTORMS
ABOVE 30 MORE THAN 60 PERCENT PROBABILITY OF THUNDERSTORMS
LAPSE RATE - THE CHANGE WITH HEIGHT OF THE TEMPERATURE. NEGATIVE VALUES INDICATE
INVERSIONS.
LIFTED CONDENSATION LEVEL - THE HEIGHT TO WHICH AN AIR PARCEL POSSESSING THE
AVERAGE DEW POINT IN THE LOWEST 4000 FEET OF THE AIRMASS AND THE FORECAST
MAXIMUM TEMPERATURE MUST BE LIFTED DRY ADIABATICALLY TO ATTAIN SATURATION.
LIFTED INDEX (LI) - THE DIFFERENCE BETWEEN THE ENVIRONMENTAL TEMPERATURE AT A
LEVEL APPROXIMATELY 18,000 FEET ABOVE THE SURFACE AND THE TEMPERATURE OF
AN AIR PARCEL LIFTED DRY ADIABATICALLY FROM THE SURFACE TO ITS LIFTED
CONDENSATION LEVEL AND THEN PSEUDOADIABATICALLY THEREAFTER TO THIS SAME
LEVEL. THE PARCEL'S INITIAL TEMPERATURE IS THE FORECAST MAXIMUM
TEMPERATURE AND ITS DEW POINT IS THE AVERAGE DEW POINT IN THE LOWEST 4000
FEET OF THE AIRMASS. NEGATIVE VALUES ARE INDICATIVE OF INSTABILITY WITH
POSITIVE VALUES SHOWING STABLE CONDITIONS.
LIFT RATE - AN EXPERIMENTAL ESTIMATE OF THE STRENGTH OF THERMALS. IT IS
COMPUTED THE SAME WAY AS THE MAXIMUM RATE OF LIFT BUT USES THE ACTUAL
LEVEL RATHER THAN THE MAXIMUM HEIGHT OF THERMALS IN THE CALCULATION.
ALSO, NONE OF THE EMPIRICAL ADJUSTMENTS BASED ON CLOUDINESS AND K-INDEX
ARE APPLIED TO THESE CALCULATIONS.
MAXIMUM HEIGHT OF THERMALS - THE HEIGHT WHERE THE DRY ADIABAT THROUGH THE
FORECAST MAXIMUM TEMPERATURE INTERSECTS THE ENVIRONMENTAL TEMPERATURE.
MAXIMUM RATE OF LIFT - AN ESTIMATE OF THE MAXIMUM STRENGTH OF THERMALS. IT
IS COMPUTED FROM AN EMPIRICAL FORMULA WHICH COMBINES THE EXPECTED MAXIMUM
HEIGHT OF THERMALS WITH THE DIFFERENCE IN THE ENVIRONMENTAL TEMPERATURES
BETWEEN THE MAXIMUM HEIGHT OF THERMALS AND THE TEMPERATURE 4,000 FEET
ABOVE THE GROUND. AFTER THIS COMPUTATION, FURTHER EMPIRICAL ADJUSTMENTS
ARE MADE BASED ON THE VALUE OF THE K-INDEX AND THE AMOUNT AND OPACITY OF
MIDDLE AND HIGH LEVEL CLOUDINESS EXPECTED BETWEEN THE TIME OF TRIGGER
TEMPERATURE AND THE TIME OF OVERDEVELOPMENT.
MIDDLE/HIGH CLOUDS - THE AMOUNT AND OPACITY OF MIDDLE (ALTOSTRATUS, ALTOCUMULUS)
OR HIGH (CIRRUS, CIRROSTRATUS, CIRROCUMULUS) CLOUDS. BROKEN MEANS THAT
BETWEEN 60% AND 90% OF THE SKY IS COVERED BY THE CLOUD, WITH OVERCAST
CONDITIONS OCCURRING WHEN MORE THAN 90% OF THE SKY IS COVERED BY THE CLOUD.
THIN IMPLIES THAT THE CLOUDS ARE PREDOMINANTLY TRANSPARENT, MEANING THAT
SOME SUNLIGHT IS REACHING THE GROUND, IN CONTRAST TO OPAQUE WHICH SUGGESTS
THAT LITTLE SUNLIGHT IS REACHING THE GROUND.
POTENTIAL HEIGHT OF WAVE - THE MINIMUM OF THE FOLLOWING TWO HEIGHTS:
1. LEVEL ABOVE THE HEIGHT OF STABLE LAYER (OR 14,000 FEET IF NONE EXISTS)
WHERE THE WIND DIRECTION CHANGES BY 30 DEGREES OR MORE
2. LEVEL ABOVE THE HEIGHT OF STABLE LAYER (OR 14,000 FEET IF NONE EXISTS)
WHERE THE WIND SPEED NO LONGER INCREASES WITH HEIGHT
PVA/NVA - POSITIVE VORTICITY ADVECTION (PVA)/NEGATIVE VORTICITY ADVECTION (NVA)
ON THE 500 MILLIBAR ISOBARIC SURFACE (APPROXIMATELY 18,000 FEET ABOVE MEAN
SEA LEVEL). WEAK PVA HAS BEEN SHOWN TO ASSIST IN MOUNTAIN WAVE SOARING.
SOARING WINDOW - THE TIME BETWEEN THE TIME THE TRIGGER TEMPERATURE IS REACHED
AND THE TIME OF OVERDEVELOPMENT.
THERMAL INDEX - THE DIFFERENCE BETWEEN THE ENVIRONMENTAL TEMPERATURE AND THE
TEMPERATURE AT A PARTICULAR LEVEL DETERMINED BY FOLLOWING THE DRY ADIABAT
THROUGH THE FORECAST MAXIMUM TEMPERATURE UP TO THAT LEVEL. NEGATIVE VALUES
ARE INDICATIVE OF THERMAL LIFT.
THERMAL SOARING INDEX - AN ADJECTIVE RATING (FOR SAILPLANES) BASED ON THE
COMPUTED MAXIMUM RATE OF LIFT, AND THE WIND SPEED AND MIDDLE AND HIGH
CLOUD COVER EXPECTED DURING THE SOARING WINDOW (THE TIME OF THE TRIGGER
TEMPERATURE AND THE TIME OF OVERDEVELOPMENT) ACCORDING TO THE FOLLOWING:
MAXIMUM RATE OF LIFT ADJECTIVE RATING
>= 800 FPM EXCELLENT
>= 400 AND < 800 FPM GOOD
>= 200 AND < 400 FPM FAIR
< 200 FPM POOR
TIME OF OVERDEVELOPMENT - THE TIME ONE OR MORE OF THE FOLLOWING PHENOMENA,
WHICH ESSENTIALLY SHUT OFF THERMAL LIFT, IS EXPECTED TO OCCUR:
1. FORMATION OF BROKEN TO OVERCAST CONVECTIVE CLOUD COVER
2. FORMATION OF SCATTERED TO NUMEROUS DOWNBURSTS
3. INITIATION OF WIDESPREAD PRECIPITATION
TIME OF TRIGGER TEMPERATURE - THE TIME THE SURFACE TEMPERATURE IS EXPECTED TO
REACH THE TRIGGER TEMPERATURE.
TRIGGER TEMPERATURE - THE SURFACE TEMPERATURE REQUIRED TO MAKE THE FIRST 4000
FEET OF THE ATMOSPHERE DRY ADIABATIC.
WAVE SOARING INDEX - AN EMPIRICAL, ADJECTIVE RATING (FOR SAILPLANES) WHICH
ATTEMPTS TO COMBINE A VARIETY OF PHENOMENA IMPORTANT IN MOUNTAIN WAVE
SOARING INTO A SINGLE INDEX NUMBER. OBJECTIVE POINTS ARE ASSIGNED TO
THESE PHENOMENA: WIND SPEED AND DIRECTION AT 14,000 FT MSL, THE STATIC
STABILITY IN THE 12,000-18,000 FT MSL LAYER, THE WIND SPEED GRADIENT ABOVE
THE STABLE LAYER, JET STREAM LOCATION AND FRONTAL AND UPPER TROUGH
MOVEMENTS.
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