658
UXUS97 KGJT 151306
SRGGJT
SOARING FORECAST
NATIONAL WEATHER SERVICE GRAND JUNCTION, COLORADO
606 AM MST SATURDAY, NOVEMBER 15, 2025
THIS FORECAST IS FOR SATURDAY, NOVEMBER 15, 2025:
IF THE TRIGGER TEMPERATURE OF 64.0 F/17.8 C IS REACHED...THEN
THERMAL SOARING INDEX....................... FAIR
MAXIMUM RATE OF LIFT........................ 362 FT/MIN (1.8 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 12180 FT MSL (6573 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 66.0 F/19.3 C
TIME OF TRIGGER TEMPERATURE.................... 1245 MST
TIME OF OVERDEVELOPMENT........................ NONE
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... BROKEN/OVERCAST THIN MIDDLE
SURFACE WINDS DURING SOARING WINDOW............ 20 MPH OR LESS
HEIGHT OF THE -3 THERMAL INDEX................. 7290 FT MSL (1683 FT AGL)
THERMAL SOARING OUTLOOK FOR SUNDAY 11/16....... POOR
WAVE SOARING INDEX............................. NOT AVAILABLE
REMARKS...
SUNRISE/SUNSET.................... 06:57:57 / 16:59:37 MST
TOTAL POSSIBLE SUNSHINE........... 10 HR 1 MIN 40 SEC (601 MIN 40 SEC)
ALTITUDE OF SUN AT 11:58:47 MST... 32.19 DEGREES
UPPER AIR DATA FROM RAWINSONDE OBSERVATION TAKEN ON 11/15/2025 AT 0500 MST
FREEZING LEVEL.................. 11886 FT MSL (6279 FT AGL)
CONVECTIVE CONDENSATION LEVEL... 16032 FT MSL (10425 FT AGL)
LIFTED CONDENSATION LEVEL....... 14437 FT MSL (8830 FT AGL)
LIFTED INDEX.................... +4.5
K INDEX......................... +22.8
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 -63.2 -81.8 235 42 22 0.2 0.1 M M M M M
45000 -62.4 -80.3 235 52 27 2.4 1.3 M M M M M
40000 -58.8 -73.8 235 60 31 1.9 1.1 M M M M M
38000 -54.8 -66.6 235 62 32 7.4 4.1 M M M M M
36000 -50.3 -58.5 235 64 33 7.4 4.1 M M M M M
34000 -45.6 -50.1 235 65 33 8.3 4.6 M M M M M
32000 -40.0 -40.0 230 63 32 8.3 4.6 M M M M M
30000 -35.6 -32.1 225 59 30 6.7 3.7 39.8 103.7 15.9 M M
29000 -33.6 -28.5 225 56 29 6.7 3.7 38.6 101.5 15.2 M M
28000 -31.6 -24.9 220 53 27 6.7 3.7 37.5 99.6 14.5 M M
27000 -29.6 -21.3 220 50 26 6.4 3.5 36.3 97.4 13.7 M M
26000 -27.7 -17.9 220 47 24 6.4 3.5 35.0 94.9 12.8 M M
25000 -25.8 -14.4 220 44 23 6.4 3.5 33.8 92.8 11.9 M M
24000 -23.8 -10.8 220 41 21 8.0 4.4 32.7 90.9 11.2 M M
23000 -21.5 -6.7 220 38 20 7.9 4.3 32.0 89.5 10.7 M M
22000 -19.2 -2.6 220 35 18 7.9 4.3 31.3 88.4 10.2 M M
21000 -17.0 1.4 220 32 17 6.3 3.4 30.5 86.9 9.6 M M
20000 -15.1 4.8 220 31 16 6.4 3.5 29.3 84.7 8.6 M M
19500 -14.2 6.4 220 30 15 6.4 3.5 28.7 83.6 8.2 M M
19000 -13.3 8.1 220 29 15 6.5 3.6 28.1 82.7 7.7 M M
18500 -12.4 9.7 220 28 15 5.5 3.0 27.5 81.6 7.2 M M
18000 -11.2 11.8 220 28 14 5.5 3.0 26.4 79.6 6.2 M M
17500 -10.4 13.3 225 27 14 5.8 3.2 25.7 78.3 5.6 M M
17000 -9.6 14.7 225 27 14 5.8 3.2 25.1 77.1 5.0 M M
16500 -8.8 16.2 225 27 14 5.7 3.1 24.4 75.9 4.4 M M
16000 -8.0 17.6 225 26 14 5.5 3.0 23.7 74.6 3.8 M M
15500 -7.2 19.0 225 26 13 5.6 3.0 23.0 73.4 3.1 M M
15000 -6.4 20.5 220 25 13 5.6 3.1 22.3 72.1 2.5 M M
14500 -5.6 21.9 220 24 12 5.4 3.0 21.6 70.9 1.8 M M
14000 -4.7 23.5 220 23 12 7.0 3.8 21.0 69.8 1.3 M M
13500 -3.6 25.5 220 23 12 6.9 3.8 20.6 69.0 0.9 M M
13000 -2.6 27.3 220 22 12 7.6 4.2 20.2 68.3 0.5 M M
12500 -1.4 29.5 220 23 12 7.7 4.2 19.8 67.7 0.2 M M
12000 -0.3 31.5 220 23 12 8.2 4.5 19.5 67.2 -0.1 543 2.8
11500 1.0 33.8 215 23 12 8.3 4.6 19.3 66.7 -0.3 491 2.5
11000 2.2 36.0 215 23 12 8.1 4.4 19.1 66.3 -0.5 439 2.2
10500 3.4 38.1 215 23 12 8.6 4.7 18.8 65.8 -0.8 389 2.0
10250 4.1 39.4 215 24 12 9.6 5.3 18.8 65.8 -0.9 361 1.8
10000 4.8 40.6 210 24 12 8.8 4.8 18.7 65.7 -0.9 333 1.7
9750 5.4 41.7 210 24 12 8.2 4.5 18.6 65.5 -1.0 307 1.6
9500 6.0 42.8 210 24 12 8.4 4.6 18.5 65.3 -1.1 281 1.4
9250 6.7 44.1 205 24 12 8.3 4.5 18.4 65.1 -1.2 254 1.3
9000 7.3 45.1 205 24 12 7.8 4.3 18.3 64.9 -1.3 229 1.2
8750 7.8 46.0 205 24 12 7.6 4.2 18.1 64.6 -1.5 204 1.0
8500 8.4 47.1 200 23 12 7.8 4.3 17.9 64.3 -1.6 179 0.9
8250 9.0 48.2 200 23 12 7.2 4.0 17.8 64.0 -1.8 155 0.8
8000 9.5 49.1 195 23 12 6.1 3.3 17.6 63.6 -2.0 132 0.7
7750 10.0 50.0 195 22 11 5.8 3.2 17.3 63.1 -2.3 111 0.6
7500 10.4 50.7 190 20 11 6.0 3.3 17.0 62.5 -2.6 91 0.5
7250 10.8 51.4 185 20 10 3.2 1.8 16.6 61.9 -2.9 71 0.4
7000 10.9 51.6 180 20 10 1.8 1.0 16.0 60.8 -3.5 60 0.3
6750 11.2 52.2 175 18 9 4.2 2.3 15.5 59.9 -4.0 45 0.2
6500 11.4 52.5 170 16 8 0.3 0.2 15.0 59.0 -4.5 31 0.2
6250 11.1 52.0 160 14 7 -8.8 -4.8 13.9 57.1 -5.6 33 0.2
6000 10.5 50.9 150 12 6 -3.6 -2.0 12.6 54.6 -6.9 44 0.2
5750 10.4 50.7 145 10 5 -3.1 -1.7 11.8 53.3 -7.7 38 0.2
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 * * * * * *
11/15/2025 AT 0800 MST | 11/15/2025 AT 1100 MST
|
CAPE... 0.0 LI... +7.3 | CAPE... 0.0 LI... +6.3
CINH... -0.2 K INDEX... +9.9 | CINH... -0.1 K INDEX... +10.1
|
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 -65.7 -86.3 260 37 19 1.7 1.0 | -65.5 -85.9 250 36 19 1.1 0.6
45000 -62.8 -81.0 250 49 25 2.9 1.6 | -63.3 -81.9 245 49 25 3.5 1.9
40000 -58.0 -72.4 235 48 25 7.7 4.2 | -57.7 -71.9 230 49 25 6.9 3.8
38000 -53.0 -63.4 235 42 22 8.2 4.5 | -53.1 -63.6 230 45 23 7.7 4.2
36000 -48.1 -54.6 240 36 19 8.2 4.5 | -48.5 -55.3 235 42 21 7.7 4.2
34000 -43.2 -45.8 240 38 19 8.2 4.5 | -43.8 -46.8 235 41 21 7.8 4.3
32000 -38.3 -36.9 240 42 22 8.2 4.5 | -39.1 -38.4 235 42 22 7.8 4.3
30000 -33.6 -28.5 240 43 22 7.5 4.1 | -34.4 -29.9 235 41 21 8.1 4.4
29000 -31.4 -24.5 240 42 22 7.5 4.1 | -32.0 -25.6 235 39 20 8.1 4.4
28000 -29.1 -20.4 245 42 21 7.5 4.1 | -29.5 -21.1 240 37 19 8.1 4.4
27000 -26.8 -16.2 245 40 21 8.0 4.4 | -27.2 -17.0 240 35 18 7.9 4.3
26000 -24.4 -11.9 250 38 20 8.0 4.4 | -24.8 -12.6 240 33 17 7.9 4.3
25000 -21.4 -6.5 250 36 18 8.1 4.4 | -21.9 -7.4 240 30 15 7.9 4.3
24000 -19.2 -2.6 255 34 18 7.1 3.9 | -19.6 -3.3 240 28 14 7.3 4.0
23000 -17.1 1.2 255 33 17 7.1 3.9 | -17.4 0.7 240 27 14 7.3 4.0
22000 -15.0 5.0 255 31 16 7.1 3.9 | -15.3 4.5 240 26 13 7.4 4.1
21000 -13.0 8.6 260 30 15 6.5 3.6 | -13.3 8.1 245 24 12 6.3 3.4
20000 -11.1 12.0 265 28 14 6.5 3.6 | -11.4 11.5 245 22 11 6.3 3.4
19500 -10.2 13.6 265 27 14 6.5 3.6 | -10.5 13.1 250 21 11 6.3 3.4
19000 -9.2 15.4 270 26 14 6.3 3.4 | -9.6 14.7 250 20 10 6.1 3.4
18500 -8.3 17.1 270 25 13 6.1 3.3 | -8.7 16.3 255 20 10 6.1 3.3
18000 -7.4 18.7 270 24 12 6.2 3.4 | -7.8 18.0 255 19 10 6.1 3.4
17500 -6.6 20.1 270 23 12 5.0 2.8 | -7.0 19.4 260 18 9 5.6 3.1
17000 -5.9 21.4 270 22 11 5.2 2.8 | -6.2 20.8 260 18 9 5.7 3.1
16500 -5.2 22.6 270 21 11 4.0 2.2 | -5.4 22.3 260 17 9 5.0 2.7
16000 -4.7 23.5 270 20 10 3.3 1.8 | -4.7 23.5 265 15 8 4.6 2.5
15500 -4.3 24.3 275 19 10 3.3 1.8 | -4.1 24.6 270 14 7 4.5 2.5
15000 -3.8 25.2 280 17 9 3.2 1.7 | -3.5 25.7 270 12 6 4.2 2.3
14500 -3.4 25.9 285 15 8 3.0 1.7 | -2.9 26.8 275 10 5 4.2 2.3
14000 -2.8 27.0 290 14 7 5.0 2.8 | -2.2 28.0 275 8 4 5.2 2.8
13500 -2.1 28.2 295 12 6 4.8 2.6 | -1.5 29.3 270 7 3 5.1 2.8
13000 -1.4 29.5 295 10 5 5.9 3.2 | -0.8 30.6 260 5 3 5.2 2.9
12500 -0.5 31.1 290 9 5 5.9 3.2 | -0.0 32.0 250 5 2 5.2 2.8
12000 0.4 32.7 285 8 4 6.2 3.4 | 0.8 33.4 235 4 2 5.8 3.2
11500 1.4 34.5 280 7 3 6.3 3.4 | 1.7 35.1 225 4 2 5.9 3.2
11000 2.4 36.3 275 6 3 6.4 3.5 | 2.6 36.7 210 4 2 6.1 3.3
10500 3.4 38.1 265 5 2 6.9 3.8 | 3.6 38.5 200 4 2 6.4 3.5
10250 3.9 39.0 255 4 2 4.4 2.4 | 4.1 39.4 195 4 2 5.3 2.9
10000 4.1 39.4 250 4 2 4.8 2.6 | 4.4 39.9 195 4 2 5.9 3.2
9750 4.7 40.5 245 4 2 7.6 4.2 | 5.0 41.0 190 4 2 7.3 4.0
9500 5.2 41.4 240 4 2 7.0 3.9 | 5.5 41.9 180 4 2 7.2 3.9
9250 5.7 42.3 230 3 2 6.5 3.6 | 6.1 43.0 175 4 2 6.2 3.4
9000 6.2 43.2 220 3 2 5.9 3.2 | 6.5 43.7 170 5 2 5.9 3.2
8750 7.1 44.8 200 3 2 6.3 3.5 | 7.5 45.5 160 5 2 7.2 3.9
8500 7.6 45.7 190 3 2 5.4 3.0 | 8.0 46.4 155 5 2 5.3 2.9
8250 7.9 46.2 175 4 2 4.7 2.6 | 8.3 46.9 155 5 3 4.2 2.3
8000 8.3 46.9 170 4 2 5.7 3.1 | 8.7 47.7 155 6 3 6.5 3.6
7750 8.8 47.8 165 4 2 5.5 3.0 | 9.2 48.6 150 5 3 6.4 3.5
7500 9.1 48.4 160 4 2 4.1 2.3 | 9.6 49.3 145 5 3 4.0 2.2
7250 9.4 48.9 155 5 2 3.3 1.8 | 9.9 49.8 145 5 3 2.6 1.4
7000 9.7 49.5 155 5 3 5.1 2.8 | 10.2 50.4 140 5 3 8.7 4.8
6750 10.1 50.2 150 5 2 3.0 1.6 | 11.1 52.0 130 4 2 10.2 5.6
6500 10.1 50.2 145 5 2 -0.6 -0.3 | 11.6 52.9 130 4 2 6.7 3.7
6250 10.1 50.2 135 5 2 1.1 0.6 | 12.1 53.8 125 3 2 6.6 3.6
6000 10.1 50.2 130 4 2 -2.8 -1.5 | 12.7 54.9 120 3 2 10.2 5.6
5750 9.4 48.9 110 4 2 -18.3 -10.0 | 13.8 56.8 115 3 1 20.0 10.9
5500 7.3 45.1 090 4 2 -38.0 -20.8 | 15.0 59.0 115 3 1 5.7 3.1
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
11/15/2025 AT 1400 MST | 11/15/2025 AT 1700 MST
|
CAPE... 0.0 LI... +4.5 | CAPE... 0.0 LI... +3.9
CINH... 0.0 K INDEX... +10.7 | CINH... -0.4 K INDEX... +8.0
|
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 -65.1 -85.2 245 36 18 1.6 0.9 | -64.8 -84.6 240 36 19 2.0 1.1
45000 -62.4 -80.3 245 45 23 2.9 1.6 | -61.7 -79.1 235 42 21 2.2 1.2
40000 -57.7 -71.9 225 50 26 5.9 3.3 | -58.3 -72.9 220 48 25 5.8 3.2
38000 -53.2 -63.8 230 47 24 7.5 4.1 | -53.5 -64.3 225 45 23 7.9 4.3
36000 -48.7 -55.7 235 45 23 7.5 4.1 | -48.8 -55.8 225 43 22 7.9 4.3
34000 -44.1 -47.4 235 42 22 7.7 4.2 | -44.2 -47.6 225 40 21 7.5 4.1
32000 -39.4 -38.9 230 40 20 7.7 4.2 | -39.6 -39.3 225 38 19 7.5 4.1
30000 -34.7 -30.5 230 35 18 7.8 4.3 | -34.9 -30.8 220 33 17 8.3 4.5
29000 -32.4 -26.3 230 32 16 7.8 4.3 | -32.4 -26.3 220 30 15 8.3 4.5
28000 -30.0 -22.0 230 29 15 7.9 4.3 | -29.9 -21.8 220 27 14 8.3 4.5
27000 -27.7 -17.9 230 26 13 7.7 4.2 | -27.5 -17.5 215 25 13 7.8 4.3
26000 -24.8 -12.6 230 24 12 7.7 4.2 | -25.2 -13.4 215 23 12 7.8 4.3
25000 -22.5 -8.5 225 23 12 7.7 4.2 | -22.3 -8.1 215 21 11 7.8 4.3
24000 -20.3 -4.5 225 21 11 7.1 3.9 | -20.2 -4.4 210 20 10 6.1 3.3
23000 -18.2 -0.8 225 20 10 7.1 3.9 | -18.4 -1.1 210 18 9 6.0 3.3
22000 -16.1 3.0 220 19 10 7.1 3.9 | -16.6 2.1 205 17 9 6.0 3.3
21000 -14.1 6.6 225 18 9 6.6 3.6 | -14.7 5.5 205 16 8 6.4 3.5
20000 -12.1 10.2 225 17 9 6.6 3.6 | -12.8 9.0 205 16 8 6.4 3.5
19500 -11.2 11.8 225 17 9 6.5 3.6 | -11.9 10.6 205 15 8 6.5 3.5
19000 -10.2 13.6 225 16 8 6.5 3.6 | -10.9 12.4 205 15 8 6.6 3.6
18500 -9.2 15.4 230 15 8 6.5 3.5 | -9.9 14.2 205 15 8 6.8 3.7
18000 -8.3 17.1 230 15 8 6.5 3.5 | -8.9 16.0 210 14 7 6.8 3.7
17500 -7.3 18.9 235 14 7 6.7 3.7 | -7.9 17.8 210 13 7 6.9 3.8
17000 -6.4 20.5 235 14 7 6.7 3.7 | -6.9 19.6 210 13 7 6.9 3.8
16500 -5.4 22.3 240 13 7 6.4 3.5 | -5.9 21.4 210 12 6 7.0 3.8
16000 -4.5 23.9 245 12 6 6.1 3.4 | -4.9 23.2 215 12 6 7.1 3.9
15500 -3.7 25.3 250 11 6 6.0 3.3 | -3.9 25.0 215 11 6 6.9 3.8
15000 -2.9 26.8 250 10 5 5.1 2.8 | -3.0 26.6 215 10 5 5.8 3.2
14500 -2.2 28.0 250 8 4 5.1 2.8 | -2.1 28.2 215 9 5 6.0 3.3
14000 -1.4 29.5 245 7 4 5.9 3.2 | -1.3 29.7 215 9 5 5.9 3.3
13500 -0.6 30.9 240 6 3 5.8 3.2 | -0.5 31.1 215 9 5 6.0 3.3
13000 0.2 32.4 230 6 3 5.4 3.0 | 0.4 32.7 215 9 5 6.0 3.3
12500 1.0 33.8 220 6 3 5.4 2.9 | 1.2 34.2 215 9 5 6.0 3.3
12000 1.8 35.2 215 6 3 5.8 3.2 | 2.1 35.8 210 9 5 6.5 3.5
11500 2.7 36.9 210 7 3 6.0 3.3 | 3.1 37.6 210 9 5 6.6 3.6
11000 3.6 38.5 205 7 4 6.1 3.4 | 4.1 39.4 210 9 5 6.5 3.6
10500 4.6 40.3 205 7 4 5.9 3.3 | 5.1 41.2 210 8 4 6.1 3.4
10250 5.0 41.0 205 7 3 7.1 3.9 | 5.6 42.1 210 8 4 7.7 4.2
10000 5.6 42.1 200 6 3 7.6 4.2 | 6.2 43.2 205 7 4 7.8 4.3
9750 6.2 43.2 200 6 3 6.9 3.8 | 6.7 44.1 205 7 3 6.5 3.5
9500 6.7 44.1 195 5 3 7.1 3.9 | 7.2 45.0 210 6 3 6.6 3.6
9250 7.3 45.1 195 5 3 6.9 3.8 | 7.7 45.9 210 5 3 7.4 4.0
9000 7.8 46.0 190 5 3 6.8 3.8 | 8.3 46.9 210 5 3 7.2 3.9
8750 8.8 47.8 185 4 2 7.1 3.9 | 9.3 48.7 215 4 2 6.4 3.5
8500 9.4 48.9 185 3 1 5.8 3.2 | 9.8 49.6 225 3 2 6.0 3.3
8250 9.7 49.5 185 2 1 5.4 3.0 | 10.2 50.4 225 3 1 5.9 3.2
8000 10.2 50.4 185 2 1 7.7 4.2 | 10.7 51.3 235 2 1 6.4 3.5
7750 10.8 51.4 185 1 1 8.3 4.5 | 11.2 52.2 260 2 1 6.7 3.7
7500 11.4 52.5 190 1 0 6.1 3.3 | 11.7 53.1 285 2 1 6.0 3.3
7250 11.8 53.2 000 0 0 4.8 2.6 | 12.1 53.8 290 2 1 5.5 3.0
7000 12.3 54.1 000 0 0 10.2 5.6 | 12.5 54.5 300 2 1 6.4 3.5
6750 13.2 55.8 000 0 0 12.0 6.6 | 13.0 55.4 305 3 1 6.9 3.8
6500 14.0 57.2 305 1 0 9.0 4.9 | 13.5 56.3 305 3 2 6.9 3.8
6250 14.6 58.3 305 1 0 8.8 4.8 | 14.1 57.4 305 4 2 7.2 3.9
6000 15.3 59.5 305 1 0 9.9 5.4 | 14.6 58.3 300 5 2 6.4 3.5
5750 16.2 61.2 310 1 0 15.1 8.3 | 14.8 58.6 300 4 2 -3.4 -1.9
5500 17.6 63.7 305 1 1 22.3 12.2 | 13.4 56.1 300 4 2 -41.3 -22.7
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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