142
UXUS97 KGJT 161307
SRGGJT
SOARING FORECAST
NATIONAL WEATHER SERVICE GRAND JUNCTION, COLORADO
607 AM MST MONDAY, FEBRUARY 16, 2026
THIS FORECAST IS FOR MONDAY, FEBRUARY 16, 2026:
IF THE TRIGGER TEMPERATURE OF 41.2 F/5.1 C IS REACHED...THEN
THERMAL SOARING INDEX....................... EXCELLENT
MAXIMUM RATE OF LIFT........................ 868 FT/MIN (4.4 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 18684 FT MSL (13076 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 61.0 F/16.6 C
TIME OF TRIGGER TEMPERATURE.................... 0845 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................. 15686 FT MSL (10077 FT AGL)
THERMAL SOARING OUTLOOK FOR TUESDAY 02/17...... FAIR
WAVE SOARING INDEX............................. NOT AVAILABLE
REMARKS...
SUNRISE/SUNSET.................... 07:03:58 / 17:52:22 MST
TOTAL POSSIBLE SUNSHINE........... 10 HR 48 MIN 24 SEC (648 MIN 24 SEC)
ALTITUDE OF SUN AT 12:28:10 MST... 38.34 DEGREES
UPPER AIR DATA FROM RAWINSONDE OBSERVATION TAKEN ON 02/16/2026 AT 0500 MST
FREEZING LEVEL.................. 6676 FT MSL (1068 FT AGL)
CONVECTIVE CONDENSATION LEVEL... 9194 FT MSL (3586 FT AGL)
LIFTED CONDENSATION LEVEL....... 13705 FT MSL (8097 FT AGL)
LIFTED INDEX.................... -3.4
K INDEX......................... +15.7
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 -54.6 -66.3 240 67 35 1.1 0.6 M M M M M
45000 -52.9 -63.2 240 79 41 1.1 0.6 M M M M M
40000 -49.4 -56.9 240 104 53 2.4 1.3 M M M M M
38000 -48.2 -54.8 240 115 59 0.1 0.0 M M M M M
36000 -48.1 -54.6 240 126 65 0.2 0.1 M M M M M
34000 -47.9 -54.2 240 140 72 -0.1 -0.0 M M M M M
32000 -46.6 -51.9 235 141 73 2.5 1.4 M M M M M
30000 -45.1 -49.2 235 142 73 2.2 1.2 M M M M M
29000 -43.8 -46.8 235 137 71 5.5 3.0 29.3 84.7 10.0 M M
28000 -42.1 -43.8 230 131 67 5.5 3.0 27.5 81.6 8.8 M M
27000 -40.5 -40.9 230 124 64 5.5 3.0 25.9 78.7 7.7 M M
26000 -38.9 -38.0 230 117 60 4.8 2.6 24.4 75.8 6.5 M M
25000 -37.4 -35.3 225 107 55 4.9 2.7 22.4 72.3 5.0 M M
24000 -36.0 -32.8 220 97 50 4.9 2.7 20.6 69.1 3.6 M M
23000 -34.4 -29.9 215 87 45 7.4 4.1 19.0 66.3 2.4 M M
22000 -32.1 -25.8 215 80 41 7.8 4.3 18.2 64.8 1.7 M M
21000 -29.8 -21.6 210 72 37 7.9 4.3 17.6 63.6 1.1 M M
20000 -26.8 -16.2 210 66 34 8.4 4.6 16.9 62.4 0.5 M M
19500 -25.5 -13.9 210 64 33 8.4 4.6 16.6 61.9 0.3 M M
19000 -24.3 -11.7 210 62 32 8.4 4.6 16.4 61.5 0.1 M M
18500 -23.0 -9.4 210 61 31 8.4 4.6 16.2 61.1 -0.1 1038 5.3
18000 -21.8 -7.2 215 59 30 7.1 3.9 15.9 60.7 -0.3 987 5.0
17500 -20.9 -5.6 215 57 30 6.5 3.5 15.4 59.6 -0.9 944 4.8
17000 -19.9 -3.8 215 56 29 6.3 3.4 14.8 58.6 -1.4 901 4.6
16500 -19.1 -2.4 220 54 28 5.4 3.0 14.1 57.4 -2.0 861 4.4
16000 -18.2 -0.8 220 53 27 5.5 3.0 13.4 56.1 -2.7 822 4.2
15500 -17.5 0.5 225 52 27 4.9 2.7 12.6 54.7 -3.4 784 4.0
15000 -16.7 1.9 225 53 27 5.0 2.7 11.8 53.3 -4.1 747 3.8
14500 -16.0 3.2 230 54 28 4.6 2.5 11.0 51.8 -4.9 710 3.6
14000 -15.4 4.3 235 54 28 4.5 2.5 10.1 50.3 -5.7 676 3.4
13500 -14.7 5.5 240 55 28 4.9 2.7 9.3 48.7 -6.5 641 3.3
13000 -13.9 7.0 240 57 29 5.3 2.9 8.6 47.4 -7.3 603 3.1
12500 -13.1 8.4 245 58 30 5.6 3.1 7.8 46.1 -8.0 564 2.9
12000 -12.2 10.0 245 57 29 6.0 3.3 7.2 45.0 -8.6 524 2.7
11500 -11.4 11.5 245 56 29 6.9 3.8 6.6 43.9 -9.2 483 2.5
11000 -10.2 13.6 245 54 28 7.9 4.3 6.3 43.3 -9.6 433 2.2
10500 -9.0 15.8 245 53 27 8.5 4.6 6.0 42.9 -9.9 383 1.9
10250 -8.4 16.9 245 53 27 8.4 4.6 6.0 42.7 -10.1 357 1.8
10000 -7.8 18.0 245 52 27 7.8 4.3 5.8 42.5 -10.2 332 1.7
9750 -7.2 19.0 245 51 26 8.0 4.4 5.7 42.2 -10.4 307 1.6
9500 -6.6 20.1 245 50 26 8.5 4.6 5.5 42.0 -10.6 282 1.4
9250 -6.0 21.2 240 50 26 8.4 4.6 5.5 41.8 -10.7 256 1.3
9000 -5.4 22.3 240 49 25 7.7 4.2 5.3 41.6 -10.9 231 1.2
8750 -4.9 23.2 240 47 24 7.9 4.3 5.2 41.3 -11.1 207 1.1
8500 -4.3 24.3 240 46 24 8.7 4.8 5.0 41.1 -11.2 181 0.9
8250 -3.7 25.3 240 45 23 8.7 4.8 5.0 40.9 -11.4 155 0.8
8000 -3.1 26.4 240 43 22 7.1 3.9 4.8 40.7 -11.6 130 0.7
7750 -2.6 27.3 240 41 21 6.9 3.8 4.6 40.3 -11.8 108 0.6
7500 -2.0 28.4 240 39 20 7.7 4.2 4.4 40.0 -12.1 85 0.4
7250 -1.5 29.3 240 37 19 7.5 4.1 4.3 39.7 -12.3 61 0.3
7000 -1.0 30.2 240 34 18 8.0 4.4 4.1 39.4 -12.5 37 0.2
6750 -0.4 31.3 235 32 16 8.0 4.4 4.0 39.2 -12.7 12 0.1
6500 0.2 32.4 235 29 15 7.6 4.2 3.8 38.9 -12.9 M M
6250 0.7 33.3 235 26 13 8.0 4.4 3.7 38.6 -13.1 M M
6000 1.4 34.5 235 24 12 9.1 5.0 3.6 38.5 -13.2 M M
5750 2.1 35.8 235 20 10 9.9 5.5 3.6 38.4 -13.3 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 * * * * * *
02/16/2026 AT 0800 MST | 02/16/2026 AT 1100 MST
|
CAPE... 0.0 LI... +4.1 | CAPE... 0.0 LI... +4.7
CINH... -0.2 K INDEX... +8.8 | CINH... 0.0 K INDEX... +5.4
|
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 -60.4 -76.7 245 68 35 1.5 0.8 | -61.0 -77.8 245 73 37 1.5 0.8
45000 -58.2 -72.8 250 88 45 1.2 0.6 | -58.7 -73.7 245 91 47 1.2 0.7
40000 -61.7 -79.1 245 110 56 -2.5 -1.4 | -62.1 -79.8 240 108 55 -2.4 -1.3
38000 -60.1 -76.2 245 111 57 7.4 4.1 | -60.3 -76.5 240 109 56 7.7 4.2
36000 -55.6 -68.1 245 106 55 7.4 4.1 | -55.7 -68.3 240 104 53 7.7 4.2
34000 -51.1 -60.0 245 101 52 7.7 4.2 | -51.1 -60.0 235 99 51 8.0 4.4
32000 -46.5 -51.7 245 98 51 7.7 4.2 | -46.3 -51.3 235 96 49 8.0 4.4
30000 -41.9 -43.4 245 95 49 7.6 4.1 | -41.6 -42.9 235 92 47 6.9 3.8
29000 -39.6 -39.3 245 91 47 7.6 4.2 | -39.5 -39.1 235 88 45 7.0 3.8
28000 -37.3 -35.1 245 88 45 7.6 4.2 | -37.5 -35.5 235 84 43 7.0 3.8
27000 -35.0 -31.0 245 84 43 7.4 4.0 | -35.4 -31.7 235 80 41 7.1 3.9
26000 -33.0 -27.4 245 78 40 6.5 3.6 | -33.2 -27.8 235 78 40 7.4 4.0
25000 -31.1 -24.0 245 72 37 6.5 3.6 | -31.0 -23.8 235 76 39 7.4 4.0
24000 -28.7 -19.7 240 65 33 7.0 3.8 | -28.8 -19.8 235 75 38 7.4 4.1
23000 -26.5 -15.7 240 64 33 7.4 4.0 | -26.1 -15.0 235 73 37 7.1 3.9
22000 -24.3 -11.7 240 62 32 7.4 4.1 | -24.0 -11.2 235 71 37 7.1 3.9
21000 -22.1 -7.8 240 61 32 6.9 3.8 | -21.9 -7.4 235 70 36 7.3 4.0
20000 -20.1 -4.2 240 59 31 6.8 3.8 | -19.7 -3.5 235 66 34 7.3 4.0
19500 -19.0 -2.2 240 58 30 6.8 3.8 | -18.6 -1.5 235 64 33 7.3 4.0
19000 -18.0 -0.4 240 57 30 6.8 3.8 | -17.5 0.5 235 63 32 7.3 4.0
18500 -17.0 1.4 240 56 29 7.3 4.0 | -16.5 2.3 235 61 31 7.1 3.9
18000 -15.9 3.4 240 55 28 7.5 4.1 | -15.4 4.3 230 59 30 7.0 3.9
17500 -14.7 5.5 240 53 27 7.5 4.1 | -14.3 6.3 230 57 30 7.0 3.9
17000 -13.6 7.5 240 52 27 7.1 3.9 | -13.3 8.1 230 56 29 6.6 3.6
16500 -12.6 9.3 235 50 26 7.2 3.9 | -12.3 9.9 230 54 28 6.7 3.7
16000 -11.6 11.1 235 49 25 6.4 3.5 | -11.3 11.7 230 52 27 6.3 3.5
15500 -10.6 12.9 235 47 24 6.3 3.5 | -10.4 13.3 230 50 26 6.3 3.4
15000 -9.7 14.5 235 45 23 6.0 3.3 | -9.4 15.1 230 48 25 6.0 3.3
14500 -8.8 16.2 235 43 22 5.8 3.2 | -8.6 16.5 230 46 24 5.8 3.2
14000 -7.9 17.8 235 41 21 5.7 3.2 | -7.7 18.1 230 44 23 5.7 3.1
13500 -7.1 19.2 235 38 20 5.6 3.1 | -6.9 19.6 225 41 21 5.5 3.0
13000 -6.3 20.7 230 36 18 5.6 3.1 | -6.1 21.0 225 39 20 5.5 3.0
12500 -5.4 22.3 230 34 17 5.9 3.2 | -5.2 22.6 225 36 18 5.7 3.1
12000 -4.6 23.7 225 31 16 5.9 3.3 | -4.4 24.1 225 33 17 5.7 3.1
11500 -3.7 25.3 225 29 15 6.4 3.5 | -3.6 25.5 220 31 16 6.3 3.4
11000 -2.8 27.0 220 27 14 6.4 3.5 | -2.7 27.1 215 28 15 6.3 3.4
10500 -1.9 28.6 220 25 13 5.8 3.2 | -1.8 28.8 215 26 14 5.9 3.2
10250 -1.5 29.3 215 24 12 6.2 3.4 | -1.4 29.5 215 26 13 6.3 3.5
10000 -0.9 30.4 215 24 12 9.2 5.0 | -0.8 30.6 210 25 13 8.1 4.5
9750 -0.2 31.6 210 24 12 8.8 4.8 | -0.2 31.6 210 24 12 8.4 4.6
9500 0.3 32.5 210 23 12 6.8 3.7 | 0.3 32.5 205 24 12 7.5 4.1
9250 0.8 33.4 210 22 11 7.2 3.9 | 0.9 33.6 205 23 12 7.8 4.3
9000 1.4 34.5 210 21 11 7.5 4.1 | 1.5 34.7 205 23 12 7.4 4.1
8750 1.9 35.4 205 22 11 7.7 4.2 | 2.0 35.6 200 22 11 7.7 4.2
8500 3.0 37.4 200 20 10 7.3 4.0 | 3.2 37.8 195 21 11 7.9 4.3
8250 3.6 38.5 200 19 10 7.7 4.2 | 3.8 38.8 195 20 10 8.6 4.7
8000 4.2 39.6 200 19 10 7.1 3.9 | 4.4 39.9 190 19 10 8.7 4.8
7750 4.6 40.3 195 17 9 6.3 3.4 | 5.0 41.0 190 18 9 8.2 4.5
7500 5.1 41.2 190 16 8 6.3 3.5 | 5.6 42.1 185 17 9 8.1 4.5
7250 5.5 41.9 190 16 8 5.7 3.1 | 6.2 43.2 185 16 8 6.9 3.8
7000 6.0 42.8 185 15 8 5.4 3.0 | 6.7 44.1 180 15 8 8.3 4.6
6750 6.4 43.5 180 14 7 6.1 3.3 | 7.4 45.3 180 14 7 9.9 5.4
6500 6.8 44.2 170 12 6 4.2 2.3 | 8.2 46.8 180 13 7 9.8 5.4
6250 7.0 44.6 165 11 6 1.8 1.0 | 9.0 48.2 175 13 7 11.3 6.2
6000 7.2 45.0 155 10 5 3.8 2.1 | 9.7 49.5 170 12 6 8.4 4.6
5750 7.3 45.1 150 7 4 -4.9 -2.7 | 10.3 50.5 175 11 6 8.0 4.4
5500 5.2 41.4 115 3 2 -64.3 -35.3 | 11.9 53.4 170 9 5 48.2 26.4
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
02/16/2026 AT 1400 MST | 02/16/2026 AT 1700 MST
|
CAPE... +0.1 LI... +2.8 | CAPE... 0.0 LI... +2.9
CINH... -0.1 K INDEX... +10.1 | CINH... -0.1 K INDEX... +10.9
|
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 -60.3 -76.5 240 77 40 0.7 0.4 | -60.1 -76.2 240 79 41 0.5 0.3
45000 -59.3 -74.7 245 97 50 0.6 0.3 | -59.3 -74.7 240 100 52 0.5 0.2
40000 -62.1 -79.8 235 106 54 -2.0 -1.1 | -60.8 -77.4 235 100 52 -1.1 -0.6
38000 -60.3 -76.5 235 104 54 7.4 4.0 | -59.8 -75.6 230 99 51 5.7 3.1
36000 -55.9 -68.6 235 98 51 7.4 4.0 | -56.5 -69.7 230 94 49 5.6 3.1
34000 -51.4 -60.5 235 93 48 8.4 4.6 | -52.3 -62.1 230 90 46 8.7 4.8
32000 -46.4 -51.5 235 90 46 8.3 4.6 | -47.2 -53.0 235 88 45 8.6 4.7
30000 -41.5 -42.7 235 88 45 6.9 3.8 | -42.2 -44.0 235 85 44 7.7 4.2
29000 -39.4 -38.9 235 86 44 7.0 3.9 | -39.9 -39.8 235 83 43 7.7 4.2
28000 -37.3 -35.1 235 85 44 7.0 3.9 | -37.6 -35.7 235 81 42 7.7 4.2
27000 -35.2 -31.4 235 83 43 7.1 3.9 | -35.3 -31.5 235 79 40 7.7 4.2
26000 -33.0 -27.4 235 81 42 7.6 4.1 | -33.1 -27.6 235 77 40 7.2 4.0
25000 -30.8 -23.4 235 79 41 7.6 4.1 | -31.0 -23.8 235 75 39 7.2 4.0
24000 -28.5 -19.3 235 78 40 7.6 4.2 | -28.8 -19.8 235 73 38 7.3 4.0
23000 -25.8 -14.4 230 74 38 7.4 4.0 | -26.7 -16.1 230 72 37 7.1 3.9
22000 -23.6 -10.5 230 70 36 7.4 4.1 | -24.1 -11.4 230 69 36 7.1 3.9
21000 -21.4 -6.5 230 67 34 6.5 3.6 | -22.0 -7.6 230 67 35 7.0 3.8
20000 -19.6 -3.3 230 65 33 6.3 3.4 | -20.0 -4.0 230 66 34 7.0 3.8
19500 -18.7 -1.7 230 63 33 6.3 3.4 | -18.9 -2.0 230 66 34 7.0 3.8
19000 -17.7 0.1 230 62 32 6.3 3.4 | -17.9 -0.2 230 65 34 7.0 3.8
18500 -16.8 1.8 225 61 32 6.3 3.4 | -16.9 1.6 230 65 33 6.8 3.7
18000 -15.9 3.4 225 60 31 6.2 3.4 | -15.9 3.4 230 63 32 6.5 3.6
17500 -14.9 5.2 225 58 30 6.2 3.4 | -14.9 5.2 225 61 32 6.4 3.5
17000 -14.0 6.8 225 56 29 6.7 3.7 | -13.9 7.0 225 60 31 7.7 4.2
16500 -12.9 8.8 225 54 28 6.7 3.7 | -12.7 9.1 225 58 30 7.6 4.2
16000 -11.9 10.6 225 52 27 7.3 4.0 | -11.6 11.1 225 56 29 7.4 4.0
15500 -10.8 12.6 225 51 26 7.4 4.1 | -10.5 13.1 225 54 28 7.2 4.0
15000 -9.6 14.7 225 50 26 7.2 4.0 | -9.4 15.1 225 52 27 7.0 3.9
14500 -8.6 16.5 225 48 25 6.9 3.8 | -8.4 16.9 225 51 26 6.5 3.6
14000 -7.6 18.3 220 45 23 6.7 3.7 | -7.5 18.5 220 50 26 6.5 3.6
13500 -6.7 19.9 220 43 22 5.6 3.1 | -6.5 20.3 220 47 24 6.1 3.3
13000 -5.8 21.6 220 40 20 5.7 3.1 | -5.6 21.9 220 44 23 6.0 3.3
12500 -5.0 23.0 215 37 19 6.5 3.6 | -4.7 23.5 215 42 21 7.0 3.9
12000 -4.0 24.8 215 35 18 6.4 3.5 | -3.7 25.3 215 40 20 6.9 3.8
11500 -3.1 26.4 210 33 17 7.1 3.9 | -2.6 27.3 210 38 20 7.6 4.1
11000 -2.1 28.2 210 32 16 7.0 3.9 | -1.5 29.3 210 37 19 7.6 4.1
10500 -1.0 30.2 205 30 16 7.0 3.8 | -0.4 31.3 205 37 19 7.4 4.0
10250 -0.5 31.1 205 30 15 7.6 4.1 | 0.1 32.2 205 37 19 7.7 4.2
10000 0.1 32.2 205 29 15 9.1 5.0 | 0.7 33.3 205 36 19 7.9 4.3
9750 0.8 33.4 200 28 15 9.4 5.2 | 1.3 34.3 200 35 18 8.7 4.8
9500 1.4 34.5 200 28 14 8.9 4.9 | 2.0 35.6 200 35 18 9.4 5.1
9250 2.1 35.8 200 27 14 9.4 5.1 | 2.6 36.7 200 35 18 9.6 5.3
9000 2.8 37.0 200 26 13 7.9 4.4 | 3.3 37.9 200 35 18 8.0 4.4
8750 3.3 37.9 200 26 13 8.1 4.4 | 3.9 39.0 200 33 17 8.1 4.4
8500 4.0 39.2 200 25 13 9.7 5.3 | 5.2 41.4 200 33 17 9.3 5.1
8250 5.4 41.7 200 24 12 9.8 5.4 | 5.9 42.6 200 33 17 9.2 5.0
8000 6.1 43.0 200 23 12 9.6 5.3 | 6.6 43.9 200 30 15 9.1 5.0
7750 6.8 44.2 200 22 11 8.9 4.9 | 7.3 45.1 200 28 15 9.1 5.0
7500 7.5 45.5 200 21 11 9.1 5.0 | 8.0 46.4 200 27 14 9.4 5.1
7250 8.1 46.6 195 21 11 8.7 4.8 | 8.6 47.5 200 26 13 8.3 4.6
7000 8.8 47.8 195 21 11 9.4 5.2 | 9.2 48.6 200 28 14 8.5 4.7
6750 9.5 49.1 195 19 10 10.1 5.6 | 9.9 49.8 200 25 13 9.7 5.3
6500 10.3 50.5 195 18 9 10.2 5.6 | 10.6 51.1 200 22 11 9.4 5.2
6250 11.1 52.0 195 17 9 11.5 6.3 | 11.4 52.5 200 20 10 10.4 5.7
6000 11.9 53.4 195 17 9 9.1 5.0 | 12.1 53.8 200 20 11 8.5 4.7
5750 12.5 54.5 195 15 8 7.6 4.2 | 12.5 54.5 195 16 8 3.6 2.0
5500 13.9 57.0 195 12 6 39.5 21.7 | 13.0 55.4 195 12 6 12.8 7.0
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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