892
UXUS97 KGJT 161307
SRGGJT
SOARING FORECAST
NATIONAL WEATHER SERVICE GRAND JUNCTION, COLORADO
707 AM MDT MONDAY, MARCH 16, 2026
THIS FORECAST IS FOR MONDAY, MARCH 16, 2026:
IF THE TRIGGER TEMPERATURE OF 56.4 F/13.5 C IS REACHED...THEN
THERMAL SOARING INDEX....................... FAIR
MAXIMUM RATE OF LIFT........................ 338 FT/MIN (1.7 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 10512 FT MSL (4905 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 60.0 F/16.0 C
TIME OF TRIGGER TEMPERATURE.................... 1445 MDT
TIME OF OVERDEVELOPMENT........................ NONE
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... NONE
SURFACE WINDS DURING SOARING WINDOW............ 20 MPH OR LESS
HEIGHT OF THE -3 THERMAL INDEX................. 9106 FT MSL (3499 FT AGL)
THERMAL SOARING OUTLOOK FOR TUESDAY 03/17...... GOOD
WAVE SOARING INDEX............................. NOT AVAILABLE
REMARKS...
SUNRISE/SUNSET.................... 07:23:16 / 19:22:02 MDT
TOTAL POSSIBLE SUNSHINE........... 11 HR 58 MIN 46 SEC (718 MIN 46 SEC)
ALTITUDE OF SUN AT 13:22:39 MDT... 49.04 DEGREES
UPPER AIR DATA FROM RAWINSONDE OBSERVATION TAKEN ON 03/16/2026 AT 0600 MDT
FREEZING LEVEL.................. 11490 FT MSL (5883 FT AGL)
CONVECTIVE CONDENSATION LEVEL... 19775 FT MSL (14168 FT AGL)
LIFTED CONDENSATION LEVEL....... 13907 FT MSL (8300 FT AGL)
LIFTED INDEX.................... +12.2
K INDEX......................... +0.0
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 -67.0 -88.6 350 52 27 1.5 0.8 M M M M M
45000 -64.0 -83.2 345 66 34 3.9 2.2 M M M M M
40000 -58.1 -72.6 330 79 41 5.6 3.1 M M M M M
38000 -53.3 -63.9 330 75 39 8.0 4.4 M M M M M
36000 -48.5 -55.3 335 72 37 8.0 4.4 M M M M M
34000 -43.0 -45.4 335 66 34 8.4 4.6 M M M M M
32000 -37.9 -36.2 330 61 31 8.4 4.6 M M M M M
30000 -32.8 -27.0 330 59 30 8.6 4.7 43.2 109.7 21.0 M M
29000 -30.3 -22.5 330 59 30 8.6 4.7 42.7 108.9 20.9 M M
28000 -27.7 -17.9 330 58 30 8.7 4.8 42.4 108.3 20.8 M M
27000 -25.5 -13.9 330 58 30 6.8 3.7 41.5 106.6 20.4 M M
26000 -23.5 -10.3 330 57 29 6.8 3.7 40.3 104.5 19.6 M M
25000 -21.4 -6.5 330 55 29 6.8 3.7 39.2 102.6 19.0 M M
24000 -19.5 -3.1 330 54 28 6.0 3.3 38.1 100.5 18.3 M M
23000 -17.7 0.1 330 50 26 6.1 3.3 36.7 98.0 17.3 M M
22000 -15.9 3.4 330 47 24 6.1 3.3 35.4 95.7 16.4 M M
21000 -14.2 6.4 325 45 23 5.4 3.0 34.0 93.2 15.4 M M
20000 -12.5 9.5 330 45 23 5.4 3.0 32.4 90.3 14.3 M M
19500 -11.7 10.9 330 45 23 5.4 3.0 31.7 89.0 13.7 M M
19000 -10.5 13.1 330 45 23 5.2 2.9 30.6 87.1 12.9 M M
18500 -9.8 14.4 330 45 23 5.0 2.8 29.8 85.6 12.2 M M
18000 -9.0 15.8 330 45 23 5.0 2.8 29.0 84.2 11.6 M M
17500 -8.3 17.1 330 45 23 5.2 2.8 28.2 82.7 11.0 M M
17000 -7.5 18.5 330 45 23 5.1 2.8 27.4 81.3 10.3 M M
16500 -6.7 19.9 335 45 23 5.3 2.9 26.6 79.9 9.7 M M
16000 -5.9 21.4 335 44 23 5.4 3.0 25.9 78.6 9.1 M M
15500 -5.1 22.8 335 43 22 5.4 2.9 25.2 77.3 8.5 M M
15000 -4.4 24.1 335 41 21 5.3 2.9 24.4 75.9 7.8 M M
14500 -3.7 25.3 335 39 20 5.4 3.0 23.7 74.6 7.1 M M
14000 -3.0 26.6 335 36 19 4.7 2.6 22.9 73.2 6.3 M M
13500 -2.3 27.9 335 33 17 5.0 2.7 22.1 71.8 5.5 M M
13000 -1.7 28.9 330 31 16 4.4 2.4 21.3 70.3 4.7 M M
12500 -1.1 30.0 330 28 14 4.5 2.5 20.4 68.7 3.9 M M
12000 -0.6 30.9 325 26 13 3.9 2.1 19.5 67.2 3.0 M M
11500 -0.0 32.0 320 24 13 3.9 2.1 18.6 65.4 2.1 M M
11000 0.5 32.9 315 23 12 2.5 1.4 17.6 63.6 1.1 M M
10500 0.8 33.4 310 22 11 2.5 1.3 16.4 61.5 0.0 M M
10250 1.0 33.8 310 21 11 3.2 1.8 15.8 60.5 -0.5 325 1.7
10000 1.2 34.2 305 19 10 2.8 1.5 15.3 59.6 -1.0 310 1.6
9750 1.4 34.5 305 18 9 2.2 1.2 14.7 58.5 -1.5 298 1.5
9500 1.6 34.9 300 16 8 2.3 1.2 14.1 57.5 -2.1 285 1.4
9250 1.8 35.2 300 15 8 2.4 1.3 13.6 56.4 -2.6 272 1.4
9000 2.0 35.6 295 13 7 4.0 2.2 13.0 55.5 -3.1 257 1.3
8750 2.4 36.3 290 12 6 4.9 2.7 12.6 54.8 -3.5 239 1.2
8500 2.8 37.0 285 10 5 4.7 2.6 12.3 54.1 -3.8 220 1.1
8250 3.2 37.8 280 9 4 4.6 2.5 11.9 53.4 -4.2 202 1.0
8000 3.5 38.3 280 7 4 4.8 2.6 11.5 52.7 -4.6 183 0.9
7750 3.9 39.0 275 6 3 4.8 2.7 11.1 52.0 -4.9 164 0.8
7500 4.3 39.7 270 5 3 5.1 2.8 10.7 51.3 -5.3 145 0.7
7250 4.7 40.5 260 4 2 5.5 3.0 10.4 50.7 -5.6 125 0.6
7000 5.2 41.4 235 3 2 5.6 3.1 10.1 50.2 -5.9 104 0.5
6750 5.6 42.1 220 3 2 5.4 3.0 9.8 49.6 -6.2 84 0.4
6500 6.0 42.8 205 3 2 3.1 1.7 9.4 48.9 -6.6 66 0.3
6250 6.0 42.8 185 4 2 -0.9 -0.5 8.7 47.7 -7.3 56 0.3
6000 6.1 43.0 170 4 2 7.1 3.9 8.1 46.5 -7.9 46 0.2
5750 6.8 44.2 160 4 2 1.7 1.0 8.0 46.4 -8.0 19 0.1
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 * * * * * *
03/16/2026 AT 0900 MDT | 03/16/2026 AT 1200 MDT
|
CAPE... 0.0 LI... +9.6 | CAPE... 0.0 LI... +9.0
CINH... -1.1 K INDEX... +4.5 | CINH... -0.0 K INDEX... +6.0
|
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 -60.7 -77.3 345 71 37 1.9 1.0 | -61.1 -78.0 345 71 37 2.3 1.3
45000 -58.0 -72.4 340 91 47 -0.5 -0.3 | -57.8 -72.0 345 89 46 -1.7 -1.0
40000 -59.8 -75.6 350 139 72 -1.0 -0.6 | -60.2 -76.4 355 136 70 -1.4 -0.8
38000 -57.3 -71.1 350 146 75 6.6 3.6 | -57.4 -71.3 355 141 72 7.4 4.0
36000 -53.3 -63.9 345 147 76 6.6 3.6 | -52.9 -63.2 350 140 72 7.4 4.0
34000 -49.2 -56.6 345 142 73 7.6 4.2 | -48.4 -55.1 350 136 70 8.0 4.4
32000 -44.6 -48.3 340 123 63 7.6 4.2 | -43.6 -46.5 350 129 67 8.0 4.4
30000 -40.1 -40.2 340 106 55 7.2 4.0 | -39.0 -38.2 350 117 60 6.7 3.7
29000 -37.9 -36.2 335 101 52 7.2 4.0 | -37.1 -34.8 345 106 54 6.6 3.6
28000 -35.8 -32.4 335 96 49 7.2 4.0 | -35.1 -31.2 345 94 49 6.6 3.6
27000 -33.6 -28.5 330 91 47 7.7 4.2 | -32.5 -26.5 345 83 43 7.0 3.9
26000 -31.2 -24.2 330 88 45 8.0 4.4 | -30.4 -22.7 345 79 40 7.0 3.9
25000 -28.3 -18.9 330 84 43 8.0 4.4 | -28.3 -18.9 340 75 38 7.0 3.9
24000 -25.9 -14.6 330 81 42 7.4 4.1 | -26.2 -15.2 340 71 36 7.3 4.0
23000 -23.7 -10.7 335 77 40 7.3 4.0 | -24.0 -11.2 340 67 35 7.3 4.0
22000 -21.5 -6.7 335 74 38 7.4 4.0 | -21.9 -7.4 340 64 33 7.3 4.0
21000 -19.5 -3.1 335 71 36 5.9 3.2 | -19.7 -3.5 340 61 31 7.4 4.0
20000 -17.7 0.1 335 68 35 6.1 3.3 | -17.5 0.5 340 59 31 7.4 4.0
19500 -16.8 1.8 335 66 34 6.1 3.3 | -16.4 2.5 340 59 30 7.4 4.1
19000 -15.9 3.4 335 64 33 6.2 3.4 | -15.3 4.5 345 58 30 7.5 4.1
18500 -15.1 4.8 340 63 32 4.8 2.6 | -14.3 6.3 345 58 30 5.9 3.2
18000 -14.4 6.1 340 61 32 4.6 2.5 | -13.4 7.9 345 57 29 5.8 3.2
17500 -13.7 7.3 340 60 31 4.2 2.3 | -12.6 9.3 345 56 29 5.5 3.0
17000 -13.2 8.2 340 58 30 3.1 1.7 | -11.8 10.8 345 55 28 5.1 2.8
16500 -12.8 9.0 340 56 29 3.1 1.7 | -11.1 12.0 345 54 28 5.2 2.9
16000 -12.3 9.9 340 55 28 3.5 1.9 | -10.5 13.1 345 52 27 3.6 2.0
15500 -11.8 10.8 340 54 28 3.5 1.9 | -9.9 14.2 345 51 26 3.8 2.1
15000 -11.3 11.7 340 52 27 3.7 2.0 | -9.4 15.1 345 49 25 3.1 1.7
14500 -10.7 12.7 340 50 26 3.8 2.1 | -9.0 15.8 345 48 25 2.9 1.6
14000 -10.2 13.6 340 48 25 3.8 2.1 | -8.6 16.5 345 46 24 2.8 1.5
13500 -9.6 14.7 340 44 23 3.9 2.1 | -8.2 17.2 345 44 23 2.7 1.5
13000 -9.0 15.8 340 41 21 3.8 2.1 | -7.8 18.0 345 42 21 2.7 1.5
12500 -8.5 16.7 335 37 19 3.8 2.1 | -7.4 18.7 345 38 20 2.6 1.4
12000 -7.9 17.8 335 32 17 3.6 2.0 | -7.0 19.4 345 35 18 2.8 1.6
11500 -7.4 18.7 330 28 15 3.4 1.8 | -6.6 20.1 340 30 16 3.2 1.8
11000 -6.9 19.6 325 24 12 2.8 1.5 | -6.1 21.0 340 26 13 3.1 1.7
10500 -6.5 20.3 325 20 10 2.1 1.1 | -5.6 21.9 335 21 11 2.9 1.6
10250 -6.3 20.7 320 18 9 2.0 1.1 | -5.4 22.3 330 18 9 2.9 1.6
10000 -6.1 21.0 320 16 8 3.2 1.7 | -5.1 22.8 330 16 8 3.7 2.0
9750 -5.8 21.6 315 14 7 3.8 2.1 | -4.8 23.4 325 14 7 3.6 2.0
9500 -5.5 22.1 315 13 6 3.1 1.7 | -4.6 23.7 320 12 6 2.9 1.6
9250 -5.3 22.5 315 11 5 3.7 2.0 | -4.3 24.3 315 9 5 3.5 1.9
9000 -4.9 23.2 310 9 5 5.0 2.7 | -3.5 25.7 295 6 3 6.4 3.5
8750 -4.5 23.9 305 7 4 5.5 3.0 | -3.0 26.6 290 5 2 6.8 3.7
8500 -3.7 25.3 300 4 2 5.5 3.0 | -2.5 27.5 280 4 2 6.2 3.4
8250 -3.3 26.1 300 3 2 5.4 2.9 | -2.1 28.2 275 3 2 4.6 2.5
8000 -2.8 27.0 295 2 1 6.6 3.6 | -1.6 29.1 260 3 1 8.8 4.8
7750 -2.3 27.9 285 1 1 7.6 4.2 | -0.8 30.6 265 2 1 11.5 6.3
7500 -1.7 28.9 000 0 0 6.3 3.4 | -0.0 32.0 265 2 1 8.2 4.5
7250 -1.3 29.7 155 1 0 5.4 3.0 | 0.5 32.9 260 2 1 5.5 3.0
7000 -0.9 30.4 145 1 1 7.1 3.9 | 1.0 33.8 255 2 1 11.6 6.4
6750 -0.3 31.5 135 2 1 7.2 4.0 | 2.1 35.8 260 2 1 13.2 7.3
6500 0.2 32.4 125 3 1 5.8 3.2 | 2.9 37.2 260 1 1 9.0 4.9
6250 0.6 33.1 120 3 2 5.9 3.2 | 3.6 38.5 255 1 1 9.2 5.0
6000 1.1 34.0 115 3 2 7.0 3.8 | 4.3 39.7 255 1 1 12.7 7.0
5750 1.7 35.1 130 3 1 9.9 5.4 | 5.7 42.3 265 1 1 24.0 13.2
5500 2.3 36.1 125 2 1 2.3 1.3 | 7.3 45.1 265 1 0 12.5 6.8
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
03/16/2026 AT 1500 MDT | 03/16/2026 AT 1800 MDT
|
CAPE... 0.0 LI... +7.7 | CAPE... 0.0 LI... +6.6
CINH... -0.1 K INDEX... +5.7 | CINH... -1.1 K INDEX... +8.3
|
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 -62.1 -79.8 345 70 36 2.0 1.1 | -63.0 -81.4 345 75 39 0.8 0.4
45000 -59.3 -74.7 345 88 45 -1.0 -0.5 | -61.9 -79.4 340 101 52 0.7 0.4
40000 -60.5 -76.9 360 131 67 -0.6 -0.3 | -60.9 -77.6 360 121 62 0.8 0.5
38000 -57.1 -70.8 360 134 69 8.2 4.5 | -56.8 -70.2 360 122 63 8.7 4.8
36000 -52.2 -62.0 355 131 68 8.2 4.5 | -51.0 -59.8 360 121 62 8.7 4.8
34000 -46.8 -52.2 355 127 65 7.8 4.3 | -46.1 -51.0 355 115 59 7.5 4.1
32000 -42.1 -43.8 355 119 61 7.8 4.3 | -41.7 -43.1 355 106 54 7.5 4.1
30000 -37.5 -35.5 355 109 56 7.4 4.1 | -37.1 -34.8 355 98 50 7.7 4.2
29000 -35.3 -31.5 355 103 53 7.4 4.1 | -34.8 -30.6 355 94 49 7.7 4.2
28000 -33.1 -27.6 355 96 49 7.4 4.1 | -32.5 -26.5 355 91 47 7.7 4.2
27000 -31.0 -23.8 355 89 46 6.1 3.4 | -30.2 -22.4 355 87 45 7.9 4.3
26000 -29.1 -20.4 350 81 42 6.3 3.4 | -27.9 -18.2 355 83 43 7.9 4.3
25000 -27.2 -17.0 345 73 38 6.3 3.4 | -25.5 -13.9 355 79 41 7.9 4.3
24000 -25.4 -13.7 340 66 34 6.4 3.5 | -23.2 -9.8 350 75 39 7.0 3.9
23000 -23.5 -10.3 340 64 33 6.4 3.5 | -21.2 -6.2 350 72 37 6.9 3.8
22000 -21.6 -6.9 340 62 32 6.4 3.5 | -18.6 -1.5 345 68 35 6.9 3.8
21000 -19.1 -2.4 345 59 30 7.3 4.0 | -16.8 1.8 345 64 33 5.0 2.8
20000 -16.9 1.6 345 57 29 7.3 4.0 | -15.3 4.5 345 61 31 5.0 2.8
19500 -15.9 3.4 345 56 29 7.3 4.0 | -14.6 5.7 345 59 31 5.1 2.8
19000 -14.8 5.4 345 56 29 7.3 4.0 | -13.9 7.0 345 58 30 5.1 2.8
18500 -13.7 7.3 345 55 28 7.1 3.9 | -13.0 8.6 350 56 29 6.3 3.5
18000 -12.7 9.1 345 55 28 7.1 3.9 | -12.1 10.2 350 55 28 6.2 3.4
17500 -11.7 10.9 345 55 28 6.6 3.6 | -11.2 11.8 350 53 28 5.9 3.2
17000 -10.7 12.7 345 55 28 6.4 3.5 | -10.4 13.3 350 53 27 5.8 3.2
16500 -9.8 14.4 345 55 28 6.2 3.4 | -9.6 14.7 350 52 27 5.6 3.1
16000 -8.9 16.0 345 54 28 5.5 3.0 | -8.8 16.2 350 52 27 5.1 2.8
15500 -8.1 17.4 345 54 28 5.7 3.1 | -8.1 17.4 350 51 26 5.2 2.9
15000 -7.4 18.7 345 53 27 4.4 2.4 | -7.3 18.9 345 50 26 4.8 2.6
14500 -6.7 19.9 345 51 26 4.5 2.5 | -6.6 20.1 345 48 25 4.9 2.7
14000 -6.2 20.8 345 49 25 3.2 1.7 | -6.0 21.2 345 46 23 4.1 2.3
13500 -5.7 21.7 345 46 24 2.9 1.6 | -5.4 22.3 345 42 22 4.0 2.2
13000 -5.3 22.5 345 43 22 1.9 1.0 | -4.8 23.4 340 39 20 4.0 2.2
12500 -5.2 22.6 345 38 20 1.4 0.8 | -4.2 24.4 340 35 18 3.9 2.2
12000 -5.0 23.0 340 34 17 2.0 1.1 | -3.7 25.3 335 31 16 4.2 2.3
11500 -4.6 23.7 340 30 15 2.5 1.4 | -3.0 26.6 330 27 14 4.4 2.4
11000 -4.2 24.4 340 25 13 3.3 1.8 | -2.3 27.9 330 24 12 5.0 2.7
10500 -3.6 25.5 335 20 10 3.8 2.1 | -1.5 29.3 325 20 10 5.3 2.9
10250 -3.3 26.1 335 18 9 4.0 2.2 | -1.0 30.2 325 18 9 5.6 3.1
10000 -3.0 26.6 335 16 8 4.7 2.6 | -0.6 30.9 325 18 9 5.6 3.1
9750 -2.6 27.3 335 14 7 5.1 2.8 | -0.2 31.6 325 16 8 5.6 3.1
9500 -2.2 28.0 330 12 6 4.8 2.6 | 0.2 32.4 325 13 7 5.3 2.9
9250 -1.8 28.8 330 10 5 5.6 3.1 | 0.7 33.3 320 11 6 6.4 3.5
9000 -1.3 29.7 325 8 4 7.5 4.1 | 1.2 34.2 320 10 5 7.7 4.3
8750 -0.7 30.7 325 7 4 8.1 4.5 | 1.8 35.2 315 9 5 7.1 3.9
8500 -0.1 31.8 320 7 3 8.4 4.6 | 2.3 36.1 315 8 4 6.7 3.7
8250 0.5 32.9 320 6 3 7.3 4.0 | 2.8 37.0 310 7 3 7.0 3.8
8000 1.0 33.8 315 5 3 6.2 3.4 | 4.0 39.2 305 6 3 9.3 5.1
7750 2.5 36.5 315 5 2 12.0 6.6 | 4.7 40.5 305 5 3 10.1 5.5
7500 3.3 37.9 315 4 2 8.3 4.5 | 5.4 41.7 305 5 3 8.3 4.5
7250 3.8 38.8 305 4 2 5.7 3.1 | 6.0 42.8 300 5 2 6.9 3.8
7000 4.4 39.9 300 4 2 12.7 6.9 | 6.6 43.9 295 5 2 10.5 5.7
6750 5.6 42.1 310 4 2 13.5 7.4 | 7.5 45.5 300 4 2 11.7 6.4
6500 6.3 43.3 305 4 2 8.5 4.7 | 8.3 46.9 295 4 2 9.5 5.2
6250 7.0 44.6 300 3 2 8.7 4.8 | 9.0 48.2 290 4 2 9.7 5.3
6000 7.7 45.9 295 3 2 13.0 7.1 | 9.7 49.5 290 4 2 10.1 5.5
5750 9.1 48.4 300 3 2 26.4 14.5 | 10.6 51.1 295 4 2 13.4 7.3
5500 10.9 51.6 290 3 2 11.0 6.0 | 11.8 53.2 285 4 2 20.7 11.4
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
________________________________________________________________________________
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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