739
UXUS97 KGJT 311306
SRGGJT
SOARING FORECAST
NATIONAL WEATHER SERVICE GRAND JUNCTION, COLORADO
706 AM MDT MONDAY, MARCH 31, 2025
THIS FORECAST IS FOR MONDAY, MARCH 31, 2025:
IF THE TRIGGER TEMPERATURE OF 44.9 F/7.2 C IS REACHED...THEN
THERMAL SOARING INDEX....................... EXCELLENT
MAXIMUM RATE OF LIFT........................ 1687 FT/MIN (8.6 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 26072 FT MSL (20463 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 70.0 F/21.6 C
TIME OF TRIGGER TEMPERATURE.................... 0700 MDT
TIME OF OVERDEVELOPMENT........................ 1000 MDT
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................. 22747 FT MSL (17138 FT AGL)
THERMAL SOARING OUTLOOK FOR TUESDAY 04/01...... FAIR
WAVE SOARING INDEX............................. NOT AVAILABLE
REMARKS...
SUNRISE/SUNSET.................... 06:59:11 / 19:37:01 MDT
TOTAL POSSIBLE SUNSHINE........... 12 HR 37 MIN 50 SEC (757 MIN 50 SEC)
ALTITUDE OF SUN AT 13:18:06 MDT... 55.12 DEGREES
UPPER AIR DATA FROM RAWINSONDE OBSERVATION TAKEN ON 03/31/2025 AT 0600 MDT
FREEZING LEVEL.................. 7477 FT MSL (1868 FT AGL)
CONVECTIVE CONDENSATION LEVEL... 10409 FT MSL (4800 FT AGL)
LIFTED CONDENSATION LEVEL....... 15675 FT MSL (10066 FT AGL)
LIFTED INDEX.................... -8.3
K INDEX......................... +18.8
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 -55.6 -68.1 265 43 22 0.8 0.5 M M M M M
45000 -54.3 -65.7 270 67 35 0.8 0.5 M M M M M
40000 -53.7 -64.7 255 82 42 0.3 0.2 M M M M M
38000 -53.4 -64.1 250 90 46 2.2 1.2 M M M M M
36000 -51.9 -61.4 250 97 50 2.4 1.3 M M M M M
34000 -50.5 -58.9 250 104 53 2.4 1.3 M M M M M
32000 -48.2 -54.8 250 105 54 3.7 2.1 M M M M M
30000 -46.0 -50.8 250 104 54 3.7 2.0 M M M M M
29000 -44.9 -48.8 250 100 51 3.7 2.0 27.8 82.1 5.1 M M
28000 -43.8 -46.8 250 93 48 3.7 2.0 25.3 77.6 3.3 M M
27000 -42.7 -44.9 250 87 45 3.7 2.0 23.0 73.5 1.5 M M
26000 -41.5 -42.7 250 80 41 6.2 3.4 21.0 69.8 -0.1 1882 9.6
25000 -39.4 -38.9 250 75 39 7.0 3.8 19.8 67.7 -1.0 1790 9.1
24000 -37.3 -35.1 250 69 36 7.0 3.8 18.8 65.8 -1.9 1698 8.6
23000 -35.2 -31.4 250 64 33 6.9 3.8 17.9 64.2 -2.7 1606 8.2
22000 -33.2 -27.8 250 60 31 6.8 3.8 16.7 62.1 -3.7 1516 7.7
21000 -31.2 -24.2 245 56 29 6.8 3.8 15.7 60.2 -4.6 1425 7.2
20000 -29.1 -20.4 245 52 27 7.9 4.3 14.8 58.6 -5.4 1332 6.8
19500 -27.9 -18.2 245 50 26 7.8 4.3 14.4 58.0 -5.8 1283 6.5
19000 -26.1 -15.0 245 47 24 7.8 4.3 13.9 57.0 -6.3 1208 6.1
18500 -25.0 -13.0 245 45 23 7.9 4.3 13.6 56.5 -6.6 1158 5.9
18000 -23.8 -10.8 240 43 22 8.3 4.5 13.3 56.0 -6.9 1109 5.6
17500 -22.5 -8.5 240 41 21 8.7 4.8 13.1 55.6 -7.1 1055 5.4
17000 -21.2 -6.2 240 39 20 8.7 4.8 13.0 55.3 -7.3 1002 5.1
16500 -20.0 -4.0 240 38 20 8.2 4.5 12.7 54.9 -7.6 950 4.8
16000 -18.8 -1.8 240 38 19 8.3 4.6 12.5 54.5 -7.9 898 4.6
15500 -17.6 0.3 240 37 19 7.9 4.3 12.2 54.0 -8.2 847 4.3
15000 -16.4 2.5 240 36 18 7.8 4.3 11.9 53.4 -8.5 798 4.1
14500 -15.3 4.5 240 34 18 7.8 4.3 11.6 52.8 -8.9 749 3.8
14000 -14.1 6.6 240 33 17 7.9 4.3 11.3 52.3 -9.3 700 3.6
13500 -13.0 8.6 240 32 16 7.8 4.3 11.0 51.7 -9.6 650 3.3
13000 -11.8 10.8 240 30 15 7.7 4.2 10.6 51.1 -10.0 602 3.1
12500 -10.7 12.7 245 28 14 7.7 4.2 10.3 50.5 -10.4 553 2.8
12000 -9.6 14.7 245 28 15 7.6 4.2 9.9 49.9 -10.8 505 2.6
11500 -8.5 16.7 245 29 15 7.3 4.0 9.6 49.3 -11.2 456 2.3
11000 -7.5 18.5 245 30 15 6.5 3.6 9.1 48.4 -11.7 412 2.1
10500 -6.5 20.3 245 30 15 6.8 3.7 8.6 47.5 -12.3 369 1.9
10250 -6.0 21.2 245 31 16 6.8 3.7 8.4 47.1 -12.6 347 1.8
10000 -5.6 21.9 245 30 16 6.5 3.5 8.1 46.6 -12.9 325 1.7
9750 -5.1 22.8 245 30 16 6.3 3.5 7.9 46.2 -13.2 304 1.5
9500 -4.6 23.7 245 30 16 7.3 4.0 7.6 45.7 -13.4 282 1.4
9250 -4.1 24.6 245 31 16 7.6 4.2 7.5 45.5 -13.6 258 1.3
9000 -3.6 25.5 245 30 16 6.6 3.6 7.3 45.1 -13.9 235 1.2
8750 -3.1 26.4 245 30 15 6.6 3.6 7.0 44.6 -14.2 214 1.1
8500 -2.6 27.3 245 29 15 8.2 4.5 6.8 44.3 -14.4 191 1.0
8250 -1.9 28.6 245 29 15 9.1 5.0 6.8 44.2 -14.5 163 0.8
8000 -1.3 29.7 245 28 15 7.1 3.9 6.6 43.9 -14.7 138 0.7
7750 -0.8 30.6 245 27 14 7.0 3.8 6.4 43.5 -15.0 116 0.6
7500 -0.2 31.6 245 26 13 8.2 4.5 6.2 43.2 -15.2 92 0.5
7250 0.4 32.7 245 25 13 8.4 4.6 6.1 43.0 -15.4 66 0.3
7000 1.0 33.8 245 23 12 8.1 4.4 6.0 42.8 -15.5 40 0.2
6750 1.6 34.9 245 22 11 7.9 4.4 5.9 42.6 -15.7 15 0.1
6500 2.2 36.0 245 20 10 8.0 4.4 5.8 42.4 -15.9 M M
6250 2.7 36.9 245 18 9 8.2 4.5 5.6 42.1 -16.1 M M
6000 3.3 37.9 245 16 8 7.2 4.0 5.5 41.9 -16.2 M M
5750 3.8 38.8 245 13 7 4.3 2.3 5.2 41.3 -16.6 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 * * * * * *
03/31/2025 AT 0900 MDT | 03/31/2025 AT 1200 MDT
|
CAPE... 0.0 LI... +1.1 | CAPE... +2.5 LI... +1.3
CINH... -0.0 K INDEX... +12.4 | CINH... -0.3 K INDEX... +10.3
|
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 -56.7 -70.1 270 42 22 0.5 0.3 | -57.6 -71.7 265 44 23 0.6 0.3
45000 -55.9 -68.6 280 64 33 0.8 0.5 | -56.7 -70.1 270 59 30 1.0 0.6
40000 -59.7 -75.5 275 92 48 -2.8 -1.5 | -60.8 -77.4 270 99 51 -3.0 -1.6
38000 -60.3 -76.5 275 101 52 2.7 1.5 | -61.1 -78.0 275 110 56 4.1 2.3
36000 -58.7 -73.7 280 103 53 2.7 1.5 | -58.6 -73.5 275 109 56 4.1 2.3
34000 -56.9 -70.4 280 105 54 6.8 3.7 | -56.0 -68.8 275 108 56 7.7 4.2
32000 -51.5 -60.7 280 97 50 8.9 4.9 | -50.6 -59.1 275 103 53 8.9 4.9
30000 -46.2 -51.2 275 90 46 8.8 4.8 | -45.3 -49.5 270 97 50 8.7 4.8
29000 -43.6 -46.5 275 87 45 8.5 4.7 | -42.8 -45.0 270 95 49 8.5 4.7
28000 -41.0 -41.8 275 84 43 8.5 4.7 | -40.2 -40.4 270 93 48 8.5 4.7
27000 -37.8 -36.0 275 80 41 8.3 4.5 | -37.0 -34.6 270 90 46 8.2 4.5
26000 -35.5 -31.9 275 77 40 7.6 4.2 | -34.8 -30.6 270 86 45 7.5 4.1
25000 -33.2 -27.8 275 74 38 7.6 4.2 | -32.5 -26.5 270 83 43 7.5 4.1
24000 -31.0 -23.8 275 70 36 7.6 4.2 | -30.3 -22.5 265 79 41 7.4 4.1
23000 -29.0 -20.2 275 65 34 6.2 3.4 | -28.5 -19.3 265 74 38 5.9 3.2
22000 -27.1 -16.8 275 59 31 6.3 3.4 | -26.7 -16.1 265 69 36 5.9 3.2
21000 -25.2 -13.4 270 54 28 6.1 3.4 | -24.9 -12.8 265 65 33 6.2 3.4
20000 -23.4 -10.1 270 48 25 6.0 3.3 | -23.0 -9.4 260 58 30 6.5 3.6
19500 -22.5 -8.5 265 45 23 6.0 3.3 | -22.0 -7.6 260 55 28 6.5 3.6
19000 -21.6 -6.9 265 43 22 6.0 3.3 | -21.0 -5.8 255 52 27 6.5 3.6
18500 -20.7 -5.3 265 40 21 6.2 3.4 | -20.0 -4.0 255 49 25 6.6 3.6
18000 -19.8 -3.6 260 38 19 6.8 3.7 | -19.0 -2.2 250 47 24 6.9 3.8
17500 -18.8 -1.8 255 36 18 6.7 3.7 | -17.9 -0.2 250 45 23 6.8 3.8
17000 -17.7 0.1 255 34 17 7.1 3.9 | -16.9 1.6 245 43 22 7.5 4.1
16500 -16.7 1.9 250 32 17 7.1 3.9 | -15.7 3.7 245 42 21 7.5 4.1
16000 -15.6 3.9 250 31 16 7.0 3.8 | -14.6 5.7 245 40 21 7.0 3.8
15500 -14.6 5.7 245 29 15 7.0 3.8 | -13.7 7.3 240 37 19 6.7 3.7
15000 -13.6 7.5 240 28 14 7.1 3.9 | -12.7 9.1 240 35 18 6.7 3.7
14500 -12.6 9.3 240 27 14 7.2 3.9 | -11.7 10.9 235 33 17 6.7 3.7
14000 -11.5 11.3 235 26 14 7.3 4.0 | -10.7 12.7 235 32 16 6.8 3.7
13500 -10.4 13.3 235 26 14 7.9 4.3 | -9.7 14.5 235 31 16 7.5 4.1
13000 -9.3 15.3 235 26 14 7.9 4.4 | -8.6 16.5 230 30 16 7.5 4.1
12500 -8.1 17.4 235 27 14 8.3 4.5 | -7.5 18.5 230 30 15 7.3 4.0
12000 -6.9 19.6 235 27 14 8.3 4.5 | -6.5 20.3 230 29 15 7.3 4.0
11500 -5.6 21.9 230 27 14 8.6 4.7 | -5.3 22.5 225 28 14 8.4 4.6
11000 -4.3 24.3 230 26 13 8.6 4.7 | -4.1 24.6 225 27 14 8.4 4.6
10500 -3.2 26.2 230 25 13 7.2 4.0 | -2.9 26.8 225 25 13 7.5 4.1
10250 -2.6 27.3 230 24 12 7.1 3.9 | -2.4 27.7 225 24 12 7.9 4.4
10000 -2.0 28.4 230 24 12 10.5 5.7 | -1.7 28.9 225 23 12 10.4 5.7
9750 -1.2 29.8 225 23 12 10.2 5.6 | -0.9 30.4 220 24 12 10.2 5.6
9500 -0.6 30.9 225 22 12 7.0 3.8 | -0.2 31.6 220 22 12 8.7 4.8
9250 0.6 33.1 220 21 11 6.8 3.7 | 0.5 32.9 220 21 11 8.9 4.9
9000 1.0 33.8 220 20 10 6.4 3.5 | 1.1 34.0 220 20 10 9.6 5.3
8750 1.6 34.9 220 19 10 7.2 4.0 | 2.6 36.7 215 20 10 9.5 5.2
8500 2.1 35.8 215 19 10 7.0 3.8 | 3.3 37.9 215 20 10 9.5 5.2
8250 2.6 36.7 210 18 9 7.3 4.0 | 4.0 39.2 215 19 10 9.8 5.4
8000 3.2 37.8 210 19 10 6.6 3.6 | 4.8 40.6 215 18 9 10.0 5.5
7750 3.6 38.5 205 18 9 6.1 3.4 | 5.5 41.9 215 18 9 9.7 5.3
7500 4.1 39.4 200 17 9 5.6 3.1 | 6.3 43.3 215 18 9 9.6 5.3
7250 4.4 39.9 190 17 9 3.7 2.0 | 6.9 44.4 215 17 9 8.5 4.7
7000 4.7 40.5 190 17 9 4.3 2.3 | 7.6 45.7 215 17 9 9.6 5.3
6750 5.1 41.2 180 15 8 5.4 2.9 | 8.4 47.1 215 16 8 11.1 6.1
6500 5.5 41.9 170 14 7 5.2 2.8 | 9.2 48.6 215 16 8 10.7 5.9
6250 5.9 42.6 165 13 7 5.2 2.9 | 10.0 50.0 215 15 8 11.9 6.5
6000 6.2 43.2 160 12 6 5.6 3.1 | 10.9 51.6 215 15 7 8.6 4.7
5750 6.7 44.1 160 10 5 9.3 5.1 | 11.5 52.7 215 14 7 10.6 5.8
5500 7.8 46.0 145 8 4 20.3 11.1 | 13.9 57.0 215 12 6 71.7 39.4
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
03/31/2025 AT 1500 MDT | 03/31/2025 AT 1800 MDT
|
CAPE... +51.4 LI... -0.3 | CAPE... +43.2 LI... -0.2
CINH... -5.6 K INDEX... +13.1 | CINH... -8.2 K INDEX... +16.8
|
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 -58.0 -72.4 270 48 25 1.4 0.8 | -57.9 -72.2 275 48 25 -0.1 -0.1
45000 -55.9 -68.6 270 66 34 1.3 0.7 | -58.1 -72.6 275 68 35 -0.2 -0.1
40000 -61.7 -79.1 270 110 57 -4.3 -2.3 | -61.8 -79.2 265 104 53 -2.6 -1.5
38000 -61.9 -79.4 270 121 62 6.2 3.4 | -61.4 -78.5 265 114 58 6.4 3.5
36000 -58.3 -72.9 275 122 63 6.1 3.3 | -57.6 -71.7 265 115 59 6.3 3.5
34000 -54.5 -66.1 275 122 63 7.6 4.2 | -53.7 -64.7 265 115 59 7.6 4.2
32000 -49.7 -57.5 275 114 59 8.1 4.4 | -49.0 -56.2 265 112 58 8.0 4.4
30000 -44.8 -48.6 275 107 55 8.4 4.6 | -44.2 -47.6 265 109 56 8.0 4.4
29000 -42.4 -44.3 270 101 52 8.1 4.5 | -41.9 -43.4 265 104 54 7.7 4.2
28000 -39.9 -39.8 270 96 49 8.2 4.5 | -39.6 -39.3 265 99 51 7.7 4.2
27000 -37.5 -35.5 265 91 47 8.2 4.5 | -37.2 -35.0 265 95 49 7.8 4.3
26000 -34.6 -30.3 265 87 45 7.5 4.1 | -35.0 -31.0 265 91 47 7.5 4.1
25000 -32.4 -26.3 265 84 43 7.5 4.1 | -32.2 -26.0 260 87 45 7.5 4.1
24000 -30.2 -22.4 265 82 42 7.5 4.1 | -30.0 -22.0 260 84 43 7.7 4.2
23000 -28.3 -18.9 260 77 40 6.0 3.3 | -28.0 -18.4 260 78 40 6.0 3.3
22000 -26.5 -15.7 260 72 37 6.0 3.3 | -26.2 -15.2 260 72 37 6.1 3.3
21000 -24.7 -12.5 260 67 34 6.0 3.3 | -24.4 -11.9 260 66 34 6.1 3.3
20000 -23.0 -9.4 260 61 31 5.9 3.2 | -22.6 -8.7 260 60 31 6.1 3.4
19500 -22.1 -7.8 260 57 30 5.9 3.2 | -21.7 -7.1 255 58 30 6.2 3.4
19000 -21.2 -6.2 255 54 28 5.9 3.2 | -20.8 -5.4 255 55 28 6.2 3.4
18500 -20.3 -4.5 255 51 26 6.4 3.5 | -19.9 -3.8 255 53 27 6.2 3.4
18000 -19.2 -2.6 255 48 25 7.9 4.3 | -18.9 -2.0 250 50 26 6.5 3.5
17500 -18.0 -0.4 250 45 23 7.8 4.3 | -18.0 -0.4 250 48 25 6.3 3.5
17000 -16.8 1.8 250 43 22 8.0 4.4 | -16.9 1.6 245 45 23 8.0 4.4
16500 -15.6 3.9 245 41 21 8.0 4.4 | -15.7 3.7 245 44 23 8.3 4.5
16000 -14.4 6.1 240 40 20 7.7 4.2 | -14.5 5.9 240 42 22 8.5 4.6
15500 -13.3 8.1 240 39 20 7.6 4.1 | -13.2 8.2 240 41 21 8.7 4.8
15000 -12.2 10.0 240 38 20 7.7 4.2 | -11.9 10.6 240 41 21 8.8 4.8
14500 -11.1 12.0 235 37 19 8.2 4.5 | -10.6 12.9 235 40 21 9.3 5.1
14000 -9.9 14.2 235 37 19 8.2 4.5 | -9.2 15.4 235 40 20 9.3 5.1
13500 -8.6 16.5 235 36 18 9.0 4.9 | -7.8 18.0 235 39 20 9.5 5.2
13000 -7.3 18.9 230 35 18 9.0 4.9 | -6.4 20.5 235 39 20 9.5 5.2
12500 -6.0 21.2 230 34 18 9.0 4.9 | -5.0 23.0 230 39 20 9.5 5.2
12000 -4.7 23.5 230 34 17 9.0 4.9 | -3.5 25.7 230 38 20 9.5 5.2
11500 -3.3 26.1 230 33 17 9.3 5.1 | -2.1 28.2 230 38 20 9.7 5.3
11000 -1.9 28.6 230 33 17 9.4 5.2 | -0.7 30.7 230 38 19 9.8 5.4
10500 -0.6 30.9 230 32 16 7.7 4.2 | 0.7 33.3 230 37 19 8.1 4.4
10250 -0.0 32.0 230 31 16 8.8 4.8 | 1.3 34.3 230 37 19 8.9 4.9
10000 0.7 33.3 230 31 16 11.4 6.2 | 2.1 35.8 230 36 19 10.8 5.9
9750 1.6 34.9 230 31 16 10.6 5.8 | 2.9 37.2 230 37 19 10.3 5.6
9500 2.3 36.1 230 31 16 9.1 5.0 | 3.6 38.5 230 36 19 9.4 5.1
9250 3.0 37.4 230 30 16 9.2 5.1 | 4.3 39.7 230 36 18 9.3 5.1
9000 4.4 39.9 230 30 15 10.4 5.7 | 5.7 42.3 230 35 18 9.9 5.4
8750 5.2 41.4 230 29 15 9.6 5.3 | 6.4 43.5 230 34 18 9.7 5.3
8500 5.9 42.6 230 29 15 9.8 5.4 | 7.2 45.0 230 34 17 9.7 5.3
8250 6.6 43.9 230 28 14 9.7 5.3 | 7.9 46.2 230 33 17 9.8 5.4
8000 7.4 45.3 235 28 14 9.9 5.4 | 8.6 47.5 230 32 17 9.8 5.3
7750 8.1 46.6 235 27 14 9.8 5.4 | 9.3 48.7 230 31 16 9.5 5.2
7500 8.9 48.0 230 26 14 10.4 5.7 | 10.1 50.2 230 30 15 10.0 5.5
7250 9.6 49.3 230 25 13 8.3 4.5 | 10.8 51.4 230 29 15 8.3 4.5
7000 10.2 50.4 235 26 13 8.8 4.9 | 11.3 52.3 230 30 15 8.4 4.6
6750 11.0 51.8 235 25 13 11.4 6.3 | 12.1 53.8 230 28 14 10.4 5.7
6500 11.8 53.2 235 23 12 10.6 5.8 | 12.8 55.0 230 26 13 9.6 5.3
6250 12.6 54.7 235 23 12 11.5 6.3 | 13.6 56.5 230 24 12 11.0 6.0
6000 13.4 56.1 235 23 12 8.8 4.8 | 14.5 58.1 230 24 13 12.2 6.7
5750 14.0 57.2 235 21 11 10.3 5.7 | 15.3 59.5 230 21 11 10.8 6.0
5500 16.1 61.0 235 18 9 59.9 32.9 | 16.2 61.2 230 17 9 14.4 7.9
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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