436
UXUS97 KGJT 021306
SRGGJT
SOARING FORECAST
NATIONAL WEATHER SERVICE GRAND JUNCTION, COLORADO
606 AM MST THURSDAY, JANUARY 2, 2025
THIS FORECAST IS FOR THURSDAY, JANUARY 2, 2025:
IF THE TRIGGER TEMPERATURE OF 49.8 F/9.9 C IS REACHED...THEN
THERMAL SOARING INDEX....................... FAIR
MAXIMUM RATE OF LIFT........................ 237 FT/MIN (1.2 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 8219 FT MSL (3380 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 47.0 F/8.8 C
TIME OF TRIGGER TEMPERATURE.................... NONE
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................. 7081 FT MSL (2242 FT AGL)
THERMAL SOARING OUTLOOK FOR FRIDAY 01/03....... FAIR
WAVE SOARING INDEX............................. NOT AVAILABLE
REMARKS...
SUNRISE/SUNSET.................... 07:33:35 / 17:03:15 MST
TOTAL POSSIBLE SUNSHINE........... 9 HR 29 MIN 40 SEC (569 MIN 40 SEC)
ALTITUDE OF SUN AT 12:18:25 MST... 27.90 DEGREES
UPPER AIR DATA FROM RAWINSONDE OBSERVATION TAKEN ON 01/02/2025 AT 0500 MST
FREEZING LEVEL.................. ENTIRE AIRMASS BELOW 32 F / 0 C
CONVECTIVE CONDENSATION LEVEL... 18710 FT MSL (13871 FT AGL)
LIFTED CONDENSATION LEVEL....... 13359 FT MSL (8519 FT AGL)
LIFTED INDEX.................... +11.8
K INDEX......................... +11.9
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 -59.3 -74.7 295 51 26 3.8 2.1 105.9 222.7 55.1 M M
45000 -56.1 -69.0 305 80 41 -0.5 -0.2 85.2 185.3 46.6 M M
40000 -60.8 -77.4 300 92 47 1.0 0.5 54.2 129.5 29.7 M M
38000 -62.3 -80.1 300 108 56 -2.3 -1.2 43.0 109.4 23.1 M M
36000 -58.2 -72.8 290 110 57 7.7 4.2 40.3 104.6 21.9 M M
34000 -54.5 -66.1 305 101 52 0.9 0.5 37.3 99.1 20.4 M M
32000 -52.0 -61.6 305 99 51 7.3 4.0 31.6 88.9 16.9 M M
30000 -47.6 -53.7 300 91 47 7.4 4.1 29.6 85.4 15.9 M M
29000 -45.1 -49.2 300 89 46 9.8 5.4 29.0 84.3 15.6 M M
28000 -42.4 -44.3 300 87 45 9.6 5.3 28.7 83.7 15.6 M M
27000 -39.5 -39.1 295 82 42 9.4 5.1 28.7 83.6 15.7 M M
26000 -36.8 -34.2 295 83 43 8.7 4.8 28.4 83.2 15.7 M M
25000 -34.2 -29.6 290 76 39 9.2 5.0 28.0 82.4 15.6 M M
24000 -32.0 -25.6 295 76 39 8.0 4.4 27.2 81.0 15.1 M M
23000 -29.3 -20.7 300 80 41 9.2 5.1 26.9 80.5 15.0 M M
22000 -26.9 -16.4 300 77 39 7.7 4.2 26.3 79.3 14.7 M M
21000 -24.7 -12.5 305 65 33 7.4 4.1 25.5 77.9 14.2 M M
20000 -22.4 -8.3 305 60 31 7.4 4.1 24.6 76.3 13.6 M M
19500 -21.3 -6.3 300 56 29 7.4 4.0 24.2 75.6 13.3 M M
19000 -20.2 -4.4 290 53 28 7.0 3.8 23.8 74.8 13.0 M M
18500 -19.3 -2.7 295 54 28 6.7 3.7 23.2 73.7 12.6 M M
18000 -18.2 -0.8 290 53 27 7.8 4.3 22.7 72.9 12.3 M M
17500 -17.2 1.0 295 54 28 3.8 2.1 21.5 70.6 11.2 M M
17000 -16.6 2.1 300 55 28 3.8 2.1 20.4 68.8 10.4 M M
16500 -16.1 3.0 300 51 26 4.5 2.5 19.4 66.9 9.5 M M
16000 -15.3 4.5 295 46 23 5.2 2.8 18.6 65.5 8.9 M M
15500 -14.6 5.7 295 44 22 5.0 2.7 17.9 64.2 8.2 M M
15000 -13.6 7.5 295 43 22 8.3 4.5 17.3 63.2 7.7 M M
14500 -12.4 9.7 295 44 22 9.1 5.0 17.1 62.7 7.5 M M
14000 -11.2 11.8 295 44 23 6.7 3.7 16.8 62.3 7.3 M M
13500 -10.1 13.8 295 43 22 7.9 4.4 16.4 61.5 7.0 M M
13000 -8.9 16.0 295 44 23 8.4 4.6 16.2 61.1 6.8 M M
12500 -7.6 18.3 295 45 23 8.0 4.4 16.0 60.7 6.6 M M
12000 -6.8 19.8 285 44 23 6.1 3.4 15.4 59.6 6.1 M M
11500 -6.6 20.1 280 40 20 -2.7 -1.5 13.9 57.1 4.8 M M
11000 -6.1 21.0 275 36 19 6.4 3.5 12.9 55.3 3.9 M M
10500 -5.2 22.6 265 33 17 6.3 3.4 12.4 54.2 3.4 M M
10250 -4.7 23.5 260 31 16 6.1 3.3 12.1 53.8 3.1 M M
10000 -4.2 24.4 260 32 16 5.7 3.1 11.8 53.2 2.9 M M
9750 -3.8 25.2 255 31 16 5.6 3.1 11.5 52.6 2.6 M M
9500 -3.4 25.9 250 29 15 5.6 3.1 11.1 52.0 2.3 M M
9250 -2.9 26.8 245 27 14 5.7 3.1 10.8 51.5 2.0 M M
9000 -2.5 27.5 245 23 12 5.5 3.0 10.5 50.9 1.7 M M
8750 -2.1 28.2 245 19 10 6.0 3.3 10.2 50.3 1.4 M M
8500 -1.7 28.9 250 14 7 0.3 0.2 9.7 49.5 1.0 M M
8250 -1.9 28.6 240 9 4 -1.2 -0.7 8.8 47.8 0.1 M M
8000 -1.7 28.9 180 6 3 5.0 2.8 8.2 46.8 -0.4 227 1.2
7750 -1.5 29.3 185 6 3 -4.3 -2.4 7.7 45.8 -0.9 214 1.1
7500 -2.1 28.2 215 4 2 -4.7 -2.6 6.3 43.3 -2.2 223 1.1
7250 -1.9 28.6 270 4 2 6.4 3.5 5.7 42.3 -2.8 210 1.1
7000 -1.4 29.5 295 6 3 6.8 3.7 5.5 41.9 -3.0 188 1.0
6750 -0.9 30.4 305 5 3 6.9 3.8 5.3 41.5 -3.3 166 0.8
6500 -0.6 30.9 315 5 2 -1.4 -0.8 4.9 40.7 -3.7 149 0.8
6250 -1.0 30.2 345 2 1 -6.2 -3.4 3.7 38.6 -4.9 155 0.8
6000 -1.2 29.8 075 2 1 2.0 1.1 2.8 37.0 -5.8 152 0.8
5750 -0.8 30.6 105 3 2 6.4 3.5 2.4 36.3 -6.2 134 0.7
5500 -0.5 31.1 130 5 2 1.8 1.0 2.0 35.6 -6.6 116 0.6
5250 -0.6 30.9 145 4 2 -5.0 -2.7 1.1 34.0 -7.5 114 0.6
5000 -1.3 29.7 130 3 2 -14.0 -7.7 -0.3 31.5 -8.9 126 0.6
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *
01/02/2025 AT 0800 MST | 01/02/2025 AT 1100 MST
|
CAPE... 0.0 LI... +3.0 | CAPE... 0.0 LI... +5.6
CINH... -0.0 K INDEX... +15.5 | CINH... 0.0 K INDEX... +10.8
|
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 -59.6 -75.3 300 51 27 -0.3 -0.2 | -60.1 -76.2 305 52 27 0.0 0.0
45000 -60.1 -76.2 305 71 37 -0.3 -0.2 | -60.1 -76.2 305 69 35 -0.1 -0.0
40000 -62.7 -80.9 300 94 48 -1.8 -1.0 | -63.0 -81.4 300 85 44 -2.0 -1.1
38000 -62.1 -79.8 300 98 51 4.8 2.6 | -61.9 -79.4 300 85 44 5.3 2.9
36000 -59.3 -74.7 305 96 49 4.8 2.6 | -58.7 -73.7 300 78 40 5.3 2.9
34000 -55.6 -68.1 310 96 49 9.0 5.0 | -55.0 -67.0 305 74 38 8.5 4.7
32000 -50.2 -58.4 310 99 51 9.0 4.9 | -49.9 -57.8 305 77 40 8.6 4.7
30000 -44.9 -48.8 310 103 53 8.8 4.8 | -44.7 -48.5 310 79 41 8.4 4.6
29000 -42.2 -44.0 310 103 53 8.8 4.8 | -42.2 -44.0 310 79 41 8.3 4.6
28000 -39.6 -39.3 310 104 53 8.8 4.8 | -39.7 -39.5 310 80 41 8.3 4.6
27000 -37.0 -34.6 310 104 54 8.3 4.5 | -37.2 -35.0 310 80 41 8.4 4.6
26000 -34.7 -30.5 315 101 52 7.6 4.2 | -34.7 -30.5 310 80 41 8.5 4.7
25000 -32.4 -26.3 315 97 50 7.6 4.2 | -32.2 -26.0 315 80 41 8.5 4.7
24000 -30.1 -22.2 315 94 48 7.4 4.1 | -29.6 -21.3 315 80 41 8.5 4.7
23000 -28.3 -18.9 315 90 46 5.8 3.2 | -26.4 -15.5 315 78 40 8.5 4.7
22000 -26.6 -15.9 310 86 44 5.8 3.2 | -23.9 -11.0 315 76 39 8.5 4.7
21000 -24.4 -11.9 310 81 42 6.2 3.4 | -21.6 -6.9 320 74 38 6.0 3.3
20000 -22.5 -8.5 305 75 38 6.2 3.4 | -19.7 -3.5 315 71 37 6.2 3.4
19500 -21.6 -6.9 305 71 37 6.2 3.4 | -18.8 -1.8 315 69 36 6.2 3.4
19000 -20.7 -5.3 305 68 35 6.2 3.4 | -17.9 -0.2 315 68 35 6.5 3.6
18500 -19.8 -3.6 305 66 34 6.5 3.6 | -17.1 1.2 315 66 34 3.5 1.9
18000 -18.8 -1.8 305 64 33 6.5 3.6 | -16.6 2.1 310 63 32 3.7 2.0
17500 -17.9 -0.2 300 62 32 6.3 3.5 | -16.0 3.2 310 60 31 3.9 2.1
17000 -17.0 1.4 300 60 31 6.0 3.3 | -15.4 4.3 310 58 30 4.0 2.2
16500 -16.1 3.0 300 58 30 6.0 3.3 | -14.9 5.2 305 55 28 4.1 2.3
16000 -15.3 4.5 300 55 29 5.9 3.2 | -14.2 6.4 305 53 27 4.8 2.7
15500 -14.4 6.1 300 53 27 5.9 3.2 | -13.5 7.7 300 51 26 4.9 2.7
15000 -13.6 7.5 300 51 26 6.3 3.4 | -12.8 9.0 300 49 25 4.6 2.5
14500 -12.6 9.3 300 49 25 6.3 3.5 | -12.2 10.0 300 46 24 4.6 2.5
14000 -11.7 10.9 300 47 24 6.8 3.7 | -11.5 11.3 300 44 23 5.6 3.1
13500 -10.7 12.7 300 45 23 7.0 3.8 | -10.6 12.9 295 42 21 5.8 3.2
13000 -9.6 14.7 300 43 22 7.2 4.0 | -9.8 14.4 295 39 20 6.8 3.7
12500 -8.6 16.5 295 41 21 7.3 4.0 | -8.7 16.3 295 37 19 7.2 3.9
12000 -7.5 18.5 295 40 20 7.0 3.9 | -7.7 18.1 295 34 18 7.2 4.0
11500 -6.5 20.3 295 37 19 6.8 3.7 | -6.6 20.1 295 32 16 7.3 4.0
11000 -5.5 22.1 290 35 18 5.5 3.0 | -5.6 21.9 295 29 15 5.9 3.3
10500 -4.8 23.4 285 32 17 4.7 2.6 | -4.8 23.4 290 27 14 5.6 3.1
10250 -4.5 23.9 285 31 16 4.3 2.4 | -4.4 24.1 290 25 13 5.1 2.8
10000 -4.2 24.4 285 30 15 3.1 1.7 | -4.1 24.6 290 24 12 4.1 2.3
9750 -4.0 24.8 280 29 15 2.7 1.5 | -3.8 25.2 290 22 12 3.7 2.0
9500 -3.8 25.2 280 26 14 3.2 1.7 | -3.5 25.7 285 20 10 3.8 2.1
9250 -3.5 25.7 275 24 12 2.6 1.4 | -3.2 26.2 280 18 9 3.7 2.0
9000 -3.3 26.1 270 23 12 1.9 1.0 | -2.9 26.8 275 17 9 3.5 1.9
8750 -3.2 26.2 265 21 11 2.9 1.6 | -2.6 27.3 270 16 8 3.2 1.8
8500 -2.9 26.8 260 19 10 4.0 2.2 | -2.4 27.7 265 13 7 3.0 1.6
8250 -2.4 27.7 255 15 8 2.3 1.3 | -1.9 28.6 260 11 6 3.1 1.7
8000 -2.1 28.2 255 14 7 3.9 2.1 | -1.6 29.1 255 11 5 5.4 2.9
7750 -1.8 28.8 245 11 6 4.8 2.6 | -1.1 30.0 245 8 4 5.4 3.0
7500 -1.5 29.3 240 9 5 3.8 2.1 | -0.8 30.6 240 6 3 3.0 1.7
7250 -1.2 29.8 240 7 4 3.3 1.8 | -0.6 30.9 235 5 2 1.5 0.8
7000 -0.9 30.4 240 5 3 4.6 2.6 | -0.4 31.3 225 3 2 7.6 4.2
6750 -0.5 31.1 220 5 3 4.7 2.6 | 0.5 32.9 215 4 2 10.1 5.5
6500 -0.3 31.5 215 4 2 2.7 1.5 | 1.0 33.8 210 3 2 6.4 3.5
6250 -0.0 32.0 210 3 2 5.1 2.8 | 1.5 34.7 205 3 1 5.6 3.1
6000 0.3 32.5 200 2 1 -2.7 -1.5 | 1.9 35.4 175 1 1 7.0 3.9
5750 -0.7 30.7 180 1 1 -22.5 -12.3 | 2.8 37.0 145 1 0 16.4 9.0
5500 -2.0 28.4 000 0 0 4.3 2.3 | 3.7 38.7 130 1 0 1.1 0.6
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
01/02/2025 AT 1400 MST | 01/02/2025 AT 1700 MST
|
CAPE... 0.0 LI... +7.3 | CAPE... 0.0 LI... +7.4
CINH... -0.0 K INDEX... +2.8 | CINH... -0.1 K INDEX... +5.0
|
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 -60.8 -77.4 300 51 26 0.6 0.3 | -61.9 -79.4 300 50 26 1.2 0.6
45000 -59.9 -75.8 300 67 34 0.3 0.1 | -60.2 -76.4 305 62 32 0.4 0.2
40000 -62.8 -81.0 300 78 40 -1.9 -1.1 | -62.9 -81.2 305 80 41 -1.9 -1.0
38000 -61.6 -78.9 300 77 40 5.0 2.8 | -61.6 -78.9 305 78 40 5.1 2.8
36000 -58.5 -73.3 305 72 37 5.0 2.8 | -58.5 -73.3 305 70 36 5.1 2.8
34000 -55.0 -67.0 305 69 35 8.5 4.6 | -54.8 -66.6 305 63 33 8.7 4.7
32000 -49.8 -57.6 310 72 37 8.6 4.7 | -49.5 -57.1 305 62 32 8.7 4.8
30000 -44.7 -48.5 315 73 38 8.6 4.7 | -44.3 -47.7 305 61 31 8.7 4.8
29000 -42.1 -43.8 310 72 37 8.6 4.7 | -41.7 -43.1 305 60 31 8.7 4.8
28000 -39.5 -39.1 310 71 37 8.6 4.7 | -39.1 -38.4 305 59 30 8.7 4.8
27000 -37.0 -34.6 310 70 36 8.2 4.5 | -36.5 -33.7 305 58 30 8.3 4.5
26000 -34.6 -30.3 305 69 36 8.1 4.4 | -33.4 -28.1 305 56 29 8.2 4.5
25000 -32.2 -26.0 305 69 35 8.1 4.4 | -31.0 -23.8 305 54 28 8.2 4.5
24000 -29.1 -20.4 305 68 35 8.3 4.6 | -28.5 -19.3 305 53 27 8.4 4.6
23000 -26.7 -16.1 310 67 34 8.3 4.6 | -26.0 -14.8 305 53 27 8.4 4.6
22000 -24.2 -11.6 310 66 34 8.3 4.6 | -23.5 -10.3 300 53 28 8.4 4.6
21000 -21.7 -7.1 310 65 33 8.4 4.6 | -21.0 -5.8 300 53 27 7.9 4.3
20000 -19.2 -2.6 310 64 33 8.4 4.6 | -18.7 -1.7 300 52 27 7.9 4.3
19500 -17.9 -0.2 310 63 33 8.4 4.6 | -17.5 0.5 300 51 26 7.9 4.3
19000 -16.7 1.9 310 63 32 8.5 4.7 | -16.3 2.7 300 50 26 7.8 4.3
18500 -15.5 4.1 315 62 32 6.7 3.7 | -15.2 4.6 300 49 25 6.9 3.8
18000 -14.5 5.9 315 60 31 6.8 3.7 | -14.2 6.4 305 47 24 7.0 3.8
17500 -13.5 7.7 315 59 30 5.8 3.2 | -13.2 8.2 305 45 23 6.6 3.6
17000 -12.7 9.1 315 57 29 5.2 2.9 | -12.2 10.0 310 43 22 6.5 3.5
16500 -11.9 10.6 315 55 28 5.0 2.7 | -11.2 11.8 310 42 21 6.2 3.4
16000 -11.3 11.7 315 52 27 3.8 2.1 | -10.4 13.3 310 40 21 5.4 3.0
15500 -10.7 12.7 315 49 25 4.0 2.2 | -9.6 14.7 310 38 20 5.5 3.0
15000 -10.2 13.6 310 45 23 2.9 1.6 | -8.9 16.0 310 36 18 3.8 2.1
14500 -9.8 14.4 310 42 22 3.1 1.7 | -8.3 17.1 310 33 17 4.1 2.2
14000 -9.4 15.1 310 38 20 2.5 1.4 | -7.8 18.0 305 31 16 2.4 1.3
13500 -9.1 15.6 305 35 18 2.4 1.3 | -7.5 18.5 300 28 15 2.3 1.2
13000 -8.7 16.3 300 32 16 3.9 2.1 | -7.1 19.2 300 26 13 3.1 1.7
12500 -8.1 17.4 300 29 15 4.3 2.4 | -6.6 20.1 295 25 13 3.3 1.8
12000 -7.4 18.7 295 26 13 5.7 3.1 | -6.1 21.0 290 23 12 4.8 2.6
11500 -6.5 20.3 290 23 12 6.2 3.4 | -5.4 22.3 280 21 11 5.2 2.9
11000 -5.6 21.9 285 21 11 6.5 3.6 | -4.6 23.7 275 19 10 5.8 3.2
10500 -4.7 23.5 280 18 9 6.7 3.7 | -3.7 25.3 265 17 9 6.1 3.3
10250 -4.2 24.4 275 17 9 6.5 3.5 | -3.3 26.1 265 16 8 5.8 3.2
10000 -3.7 25.3 275 16 8 5.8 3.2 | -2.9 26.8 260 16 8 5.6 3.1
9750 -3.3 26.1 270 15 8 5.5 3.0 | -2.5 27.5 255 15 8 5.8 3.2
9500 -2.9 26.8 265 14 7 5.3 2.9 | -2.1 28.2 250 14 7 5.6 3.1
9250 -2.5 27.5 255 12 6 6.2 3.4 | -1.6 29.1 245 13 7 6.5 3.5
9000 -2.0 28.4 250 12 6 7.0 3.9 | -0.6 30.9 235 12 6 5.6 3.1
8750 -1.5 29.3 245 11 6 5.0 2.7 | -0.3 31.5 230 11 5 4.9 2.7
8500 -1.2 29.8 235 10 5 4.0 2.2 | 0.1 32.2 225 9 5 5.8 3.2
8250 -0.4 31.3 225 8 4 5.8 3.2 | 0.6 33.1 220 9 4 6.2 3.4
8000 0.0 32.0 220 8 4 6.0 3.3 | 1.1 34.0 210 8 4 5.7 3.1
7750 0.5 32.9 215 6 3 5.6 3.1 | 1.5 34.7 210 7 3 5.4 3.0
7500 0.9 33.6 205 5 3 5.1 2.8 | 1.9 35.4 200 6 3 5.6 3.1
7250 1.3 34.3 190 4 2 4.1 2.3 | 2.3 36.1 190 5 3 5.8 3.2
7000 1.7 35.1 175 4 2 7.9 4.3 | 2.8 37.0 180 4 2 4.9 2.7
6750 2.4 36.3 180 3 2 10.4 5.7 | 3.1 37.6 180 3 2 5.4 2.9
6500 3.1 37.6 180 3 1 8.7 4.8 | 3.6 38.5 175 2 1 5.7 3.1
6250 3.8 38.8 180 2 1 8.4 4.6 | 4.0 39.2 165 1 1 8.4 4.6
6000 4.4 39.9 165 2 1 9.6 5.3 | 4.6 40.3 145 1 0 2.7 1.5
5750 5.3 41.5 155 2 1 14.5 8.0 | 4.1 39.4 080 1 0 -16.7 -9.1
5500 6.3 43.3 150 2 1 6.5 3.6 | 3.4 38.1 025 1 1 14.7 8.0
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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