297
UXUS97 KBOU 020124
SRGBOU
SOARING FORECAST
NATIONAL WEATHER SERVICE DENVER/BOULDER, COLORADO
1823 MST WEDNESDAY, JANUARY 1, 2025
THIS FORECAST IS FOR THURSDAY, JANUARY 2, 2025:
IF THE TRIGGER TEMPERATURE OF 46.3 F/7.9 C IS REACHED...THEN
THERMAL SOARING INDEX....................... POOR
MAXIMUM RATE OF LIFT........................ 69 FT/MIN (0.4 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 9191 FT MSL (3875 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 46.0 F/8.2 C
TIME OF TRIGGER TEMPERATURE.................... 1415 MST
TIME OF OVERDEVELOPMENT........................ NONE
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... OVERCAST OPAQUE HIGH
SURFACE WINDS DURING SOARING WINDOW............ 20 MPH OR LESS
HEIGHT OF THE -3 THERMAL INDEX................. 7346 FT MSL (2029 FT AGL)
THERMAL SOARING OUTLOOK FOR FRIDAY 01/03....... FAIR
WAVE SOARING INDEX............................. POOR
WAVE SOARING INDEX TREND (TO 1700 MST)......... NO CHANGE
HEIGHT OF STABLE LAYER (12-18K FT MSL)......... NONE
WEAK PVA/NVA (THROUGH 1700 MST)................ WEAK NVA
POTENTIAL HEIGHT OF WAVE....................... 30422 FT MSL (25106 FT AGL)
WAVE SOARING OUTLOOK FOR FRIDAY 01/03.......... FAIR
REMARKS...
SUNRISE/SUNSET.................... 07:20:50 / 16:46:42 MST
TOTAL POSSIBLE SUNSHINE........... 9 HR 25 MIN 52 SEC (565 MIN 52 SEC)
ALTITUDE OF SUN AT 12:03:46 MST... 27.39 DEGREES
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 01/02/2025 AT 0500 MST
FREEZING LEVEL.................. 5681 FT MSL (365 FT AGL)
ADDITIONAL FREEZING LEVEL....... 6104 FT MSL (788 FT AGL)
CONVECTIVE CONDENSATION LEVEL... 15620 FT MSL (10304 FT AGL)
LIFTED CONDENSATION LEVEL....... 12922 FT MSL (7606 FT AGL)
LIFTED INDEX.................... +7.6
K INDEX......................... +14.1
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 -58.3 -72.9 295 52 27 0.7 0.4 M M M M M
45000 -57.2 -71.0 300 63 33 0.7 0.4 M M M M M
40000 -58.1 -72.6 295 77 40 -0.8 -0.4 M M M M M
38000 -58.2 -72.8 295 82 42 2.1 1.1 M M M M M
36000 -56.9 -70.4 295 86 44 2.1 1.1 M M M M M
34000 -55.7 -68.3 300 90 47 1.7 0.9 M M M M M
32000 -52.6 -62.7 295 96 49 4.9 2.7 M M M M M
30000 -49.5 -57.1 295 100 51 7.6 4.2 26.2 79.1 13.7 M M
29000 -47.0 -52.6 295 96 50 8.4 4.6 25.5 77.9 13.4 M M
28000 -44.5 -48.1 300 93 48 8.4 4.6 25.0 76.9 13.2 M M
27000 -42.0 -43.6 300 89 46 8.5 4.6 24.6 76.2 13.0 M M
26000 -39.6 -39.3 300 85 44 7.8 4.3 23.9 74.9 12.6 M M
25000 -37.3 -35.1 300 79 41 7.8 4.3 23.1 73.5 12.1 M M
24000 -34.9 -30.8 295 74 38 7.8 4.3 22.4 72.4 11.8 M M
23000 -32.8 -27.0 295 71 36 6.8 3.7 21.5 70.6 11.1 M M
22000 -30.7 -23.3 295 68 35 6.8 3.7 20.4 68.6 10.3 M M
21000 -28.7 -19.7 300 65 34 6.8 3.8 19.4 66.9 9.6 M M
20000 -26.5 -15.7 300 64 33 7.6 4.2 18.5 65.3 9.0 M M
19500 -25.4 -13.7 300 63 32 7.6 4.2 18.1 64.6 8.7 M M
19000 -24.2 -11.6 300 62 32 7.7 4.2 17.8 64.0 8.4 M M
18500 -23.1 -9.6 300 61 31 7.7 4.2 17.5 63.4 8.2 M M
18000 -21.9 -7.4 300 60 31 7.7 4.2 17.1 62.8 7.9 M M
17500 -20.2 -4.4 300 59 30 7.7 4.2 16.6 61.8 7.5 M M
17000 -19.1 -2.4 300 57 29 7.9 4.3 16.2 61.2 7.2 M M
16500 -17.9 -0.2 300 55 28 7.9 4.4 15.9 60.7 7.0 M M
16000 -16.8 1.8 300 53 28 7.5 4.1 15.6 60.1 6.7 M M
15500 -15.6 3.9 300 52 27 7.5 4.1 15.2 59.4 6.4 M M
15000 -14.5 5.9 300 50 26 7.2 3.9 14.8 58.7 6.1 M M
14500 -13.5 7.7 295 47 24 7.0 3.8 14.4 57.9 5.7 M M
14000 -12.5 9.5 295 44 23 6.8 3.7 13.9 57.1 5.3 M M
13500 -11.5 11.3 295 42 22 6.6 3.6 13.4 56.1 4.8 M M
13000 -10.5 13.1 290 40 20 6.4 3.5 12.9 55.2 4.4 M M
12500 -9.6 14.7 290 37 19 6.1 3.4 12.3 54.1 3.8 M M
12000 -8.7 16.3 290 34 18 6.0 3.3 11.7 53.1 3.3 M M
11500 -7.8 18.0 285 31 16 5.8 3.2 11.1 51.9 2.7 M M
11000 -7.0 19.4 285 28 14 6.0 3.3 10.5 50.8 2.2 M M
10500 -6.0 21.2 285 26 13 6.1 3.3 9.9 49.8 1.6 M M
10250 -5.6 21.9 285 24 13 6.8 3.7 9.6 49.3 1.4 M M
10000 -5.1 22.8 285 23 12 4.2 2.3 9.3 48.8 1.1 M M
9750 -4.9 23.2 285 22 11 4.3 2.3 8.8 47.9 0.6 M M
9500 -4.4 24.1 280 21 11 6.9 3.8 8.5 47.4 0.3 M M
9250 -4.0 24.8 280 19 10 6.0 3.3 8.3 46.9 0.1 M M
9000 -3.6 25.5 275 18 9 3.9 2.2 7.9 46.3 -0.2 255 1.3
8750 -3.3 26.1 275 16 8 4.0 2.2 7.4 45.4 -0.7 240 1.2
8500 -2.9 26.8 275 14 7 5.9 3.2 7.1 44.7 -1.1 220 1.1
8250 -2.5 27.5 270 11 6 4.6 2.5 6.7 44.1 -1.4 201 1.0
8000 -2.2 28.0 265 9 5 2.8 1.5 6.3 43.3 -1.8 185 0.9
7750 -2.0 28.4 255 7 4 3.8 2.1 5.7 42.3 -2.3 171 0.9
7500 -1.6 29.1 245 5 3 5.1 2.8 5.4 41.6 -2.7 152 0.8
7250 -1.3 29.7 230 4 2 4.1 2.3 5.0 40.9 -3.1 134 0.7
7000 -1.0 30.2 210 3 1 3.5 1.9 4.5 40.1 -3.5 118 0.6
6750 -0.7 30.7 180 2 1 4.4 2.4 4.0 39.3 -4.0 102 0.5
6500 -0.3 31.5 150 2 1 3.9 2.1 3.7 38.6 -4.4 85 0.4
6250 -0.1 31.8 135 3 1 2.1 1.1 3.1 37.6 -4.9 71 0.4
6000 0.0 32.0 125 3 2 3.0 1.6 2.6 36.6 -5.5 58 0.3
5750 0.2 32.4 115 4 2 -0.0 -0.0 2.0 35.6 -6.1 46 0.2
5500 -0.2 31.6 120 4 2 -12.0 -6.6 0.9 33.6 -7.2 51 0.3
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *
01/02/2025 AT 0800 MST | 01/02/2025 AT 1100 MST
|
CAPE... 0.0 LI... +2.7 | CAPE... 0.0 LI... +3.5
CINH... -0.1 K INDEX... +12.8 | CINH... -0.0 K INDEX... +7.7
|
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 -58.3 -72.9 300 50 26 0.8 0.4 | -58.5 -73.3 295 52 27 0.3 0.1
45000 -57.2 -71.0 300 62 32 0.7 0.4 | -58.1 -72.6 295 65 33 0.2 0.1
40000 -57.8 -72.0 300 82 42 -0.5 -0.3 | -59.0 -74.2 310 89 46 -0.7 -0.4
38000 -57.7 -71.9 300 88 45 2.8 1.5 | -58.7 -73.7 310 99 51 2.5 1.4
36000 -56.0 -68.8 305 88 45 2.9 1.6 | -57.3 -71.1 310 102 53 2.5 1.4
34000 -54.0 -65.2 305 88 46 3.4 1.9 | -55.6 -68.1 305 106 54 6.3 3.5
32000 -51.6 -60.9 305 89 46 4.0 2.2 | -51.3 -60.3 310 107 55 7.1 3.9
30000 -49.2 -56.6 310 89 46 6.1 3.3 | -46.9 -52.4 315 109 56 8.9 4.9
29000 -47.1 -52.8 310 86 44 7.0 3.8 | -44.3 -47.7 315 109 56 8.8 4.8
28000 -45.0 -49.0 305 83 43 7.0 3.8 | -41.6 -42.9 315 110 56 8.8 4.8
27000 -42.9 -45.2 305 81 42 6.9 3.8 | -39.0 -38.2 320 110 57 9.0 5.0
26000 -40.5 -40.9 305 78 40 8.2 4.5 | -36.8 -34.2 320 104 54 6.8 3.7
25000 -38.1 -36.6 305 74 38 8.2 4.5 | -34.8 -30.6 315 97 50 6.8 3.7
24000 -35.6 -32.1 305 71 36 8.3 4.5 | -32.7 -26.9 315 90 46 6.9 3.8
23000 -33.3 -27.9 305 68 35 7.6 4.2 | -30.8 -23.4 315 83 43 6.0 3.3
22000 -31.0 -23.8 305 67 34 7.6 4.2 | -29.0 -20.2 315 76 39 6.0 3.3
21000 -28.7 -19.7 305 65 34 7.6 4.2 | -26.8 -16.2 310 68 35 6.4 3.5
20000 -26.5 -15.7 305 64 33 7.5 4.1 | -24.8 -12.6 310 64 33 6.6 3.6
19500 -24.8 -12.6 305 62 32 7.6 4.1 | -23.8 -10.8 310 61 32 6.6 3.6
19000 -23.6 -10.5 305 62 32 7.6 4.1 | -22.8 -9.0 310 59 30 6.6 3.6
18500 -22.5 -8.5 305 61 31 7.7 4.2 | -21.8 -7.2 305 57 29 6.6 3.6
18000 -21.3 -6.3 305 61 31 7.8 4.3 | -20.9 -5.6 305 56 29 6.6 3.6
17500 -20.2 -4.4 305 61 31 7.8 4.3 | -19.9 -3.8 305 55 28 6.5 3.6
17000 -19.0 -2.2 300 61 31 7.5 4.1 | -18.9 -2.0 305 55 28 6.4 3.5
16500 -17.9 -0.2 300 60 31 7.6 4.1 | -18.0 -0.4 305 55 28 6.4 3.5
16000 -16.8 1.8 300 60 31 7.4 4.1 | -17.0 1.4 305 54 28 6.6 3.6
15500 -15.7 3.7 300 59 30 7.4 4.1 | -16.0 3.2 305 54 28 6.6 3.6
15000 -14.6 5.7 300 58 30 7.3 4.0 | -15.0 5.0 300 54 28 7.1 3.9
14500 -13.6 7.5 300 56 29 7.2 4.0 | -14.0 6.8 300 53 27 7.2 4.0
14000 -12.5 9.5 300 54 28 7.0 3.8 | -12.9 8.8 300 52 27 7.2 3.9
13500 -11.5 11.3 300 52 27 6.6 3.6 | -11.9 10.6 300 51 26 7.2 3.9
13000 -10.5 13.1 300 49 25 6.6 3.6 | -10.8 12.6 300 50 26 7.3 4.0
12500 -9.6 14.7 300 46 24 6.6 3.6 | -9.7 14.5 300 48 25 7.4 4.1
12000 -8.6 16.5 300 43 22 6.8 3.7 | -8.6 16.5 295 46 24 7.5 4.1
11500 -7.6 18.3 300 41 21 7.3 4.0 | -7.5 18.5 295 44 23 7.5 4.1
11000 -6.5 20.3 295 39 20 7.1 3.9 | -6.4 20.5 295 42 22 7.7 4.2
10500 -5.5 22.1 295 37 19 6.5 3.6 | -5.2 22.6 295 40 21 8.1 4.4
10250 -5.0 23.0 295 37 19 7.3 4.0 | -4.7 23.5 295 39 20 6.4 3.5
10000 -4.5 23.9 295 36 19 4.4 2.4 | -4.3 24.3 295 39 20 4.8 2.6
9750 -4.3 24.3 290 36 18 4.6 2.5 | -3.8 25.2 295 38 19 7.7 4.2
9500 -3.7 25.3 290 34 17 7.7 4.2 | -3.2 26.2 290 36 19 9.9 5.4
9250 -3.2 26.2 290 31 16 6.6 3.6 | -2.5 27.5 290 34 18 8.2 4.5
9000 -2.8 27.0 285 29 15 4.1 2.2 | -2.0 28.4 290 33 17 6.0 3.3
8750 -2.6 27.3 285 27 14 4.1 2.2 | -1.5 29.3 290 31 16 7.7 3.8
8500 -2.1 28.2 280 24 13 6.1 3.4 | -0.9 30.4 290 29 15 8.9 4.9
8250 -1.7 28.9 280 21 11 5.0 2.7 | -0.3 31.5 290 27 14 6.6 3.6
8000 -1.4 29.5 275 19 10 3.7 2.0 | 0.1 32.2 290 25 13 4.1 2.3
7750 -1.1 30.0 275 16 8 4.6 2.5 | 0.4 32.7 290 23 12 6.3 3.5
7500 -0.7 30.7 265 13 7 5.7 3.1 | 1.0 33.8 295 20 10 7.0 3.8
7250 -0.3 31.5 260 10 5 4.7 2.6 | 1.4 34.5 295 18 9 4.7 2.6
7000 0.0 32.0 255 9 4 4.0 2.2 | 1.7 35.1 290 16 8 3.0 1.6
6750 0.4 32.7 250 7 4 5.0 2.8 | 2.0 35.6 290 14 7 6.4 3.5
6500 0.7 33.3 225 5 3 3.8 2.1 | 2.6 36.7 290 10 5 7.6 4.2
6250 0.9 33.6 205 4 2 1.1 0.6 | 3.1 37.6 290 8 4 5.5 3.0
6000 1.0 33.8 190 4 2 2.9 1.6 | 3.5 38.3 290 7 3 5.5 3.0
5750 1.1 34.0 170 4 2 -3.5 -1.9 | 3.9 39.0 295 5 3 7.6 4.2
5500 0.1 32.2 160 4 2 -26.3 -14.4 | 4.7 40.5 295 3 2 13.9 7.6
01/02/2025 AT 1400 MST | 01/02/2025 AT 1700 MST
|
CAPE... 0.0 LI... +6.8 | CAPE... 0.0 LI... +7.8
CINH... -0.1 K INDEX... -3.5 | CINH... -0.0 K INDEX... -3.6
|
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 -59.5 -75.1 300 58 30 0.3 0.2 | -60.4 -76.7 305 61 31 0.2 0.1
45000 -59.0 -74.2 300 75 38 0.3 0.1 | -60.1 -76.2 305 78 40 0.1 0.1
40000 -61.7 -79.1 305 95 49 -1.9 -1.0 | -62.2 -80.0 310 94 48 -1.5 -0.8
38000 -61.4 -78.5 310 99 51 4.2 2.3 | -61.6 -78.9 310 95 49 4.3 2.4
36000 -58.9 -74.0 305 97 50 4.1 2.3 | -59.0 -74.2 310 89 46 4.3 2.4
34000 -56.2 -69.2 305 95 49 8.4 4.6 | -56.1 -69.0 310 83 43 8.8 4.9
32000 -51.0 -59.8 305 93 48 8.6 4.7 | -51.0 -59.8 315 84 43 8.4 4.6
30000 -45.9 -50.6 310 91 47 8.6 4.7 | -45.3 -49.5 315 84 43 9.0 4.9
29000 -42.7 -44.9 310 90 46 8.5 4.7 | -42.6 -44.7 315 84 43 9.0 4.9
28000 -40.1 -40.2 310 89 46 8.5 4.7 | -39.9 -39.8 315 84 43 9.0 4.9
27000 -37.6 -35.7 315 89 46 8.4 4.6 | -37.2 -35.0 315 83 43 8.6 4.7
26000 -35.1 -31.2 315 88 45 8.3 4.5 | -34.7 -30.5 315 82 42 8.5 4.7
25000 -32.6 -26.7 320 88 45 8.3 4.5 | -32.1 -25.8 315 80 41 8.5 4.7
24000 -30.2 -22.4 320 87 45 8.1 4.4 | -29.6 -21.3 315 79 41 8.1 4.4
23000 -27.9 -18.2 320 86 44 7.5 4.1 | -27.3 -17.1 320 77 40 7.7 4.2
22000 -25.7 -14.3 320 84 43 7.5 4.1 | -25.0 -13.0 320 76 39 7.7 4.2
21000 -23.4 -10.1 325 81 42 6.6 3.6 | -22.7 -8.9 320 74 38 7.1 3.9
20000 -21.6 -6.9 320 75 39 6.1 3.3 | -20.6 -5.1 320 71 36 7.0 3.9
19500 -20.7 -5.3 320 72 37 6.1 3.3 | -19.5 -3.1 320 69 35 7.0 3.9
19000 -19.8 -3.6 320 69 36 6.0 3.3 | -18.5 -1.3 320 67 34 7.0 3.9
18500 -18.9 -2.0 315 66 34 5.7 3.1 | -17.4 0.7 320 65 33 7.1 3.9
18000 -18.1 -0.6 315 63 33 5.1 2.8 | -16.4 2.5 320 62 32 7.2 3.9
17500 -17.4 0.7 315 60 31 5.2 2.8 | -15.3 4.5 320 60 31 7.1 3.9
17000 -16.7 1.9 310 57 29 3.9 2.2 | -14.3 6.3 320 59 30 6.3 3.5
16500 -16.1 3.0 310 53 27 4.0 2.2 | -13.3 8.1 315 58 30 6.5 3.6
16000 -15.4 4.3 305 50 26 5.1 2.8 | -12.5 9.5 315 56 29 4.6 2.5
15500 -14.6 5.7 305 47 24 5.5 3.0 | -11.8 10.8 315 53 27 4.5 2.5
15000 -13.8 7.2 305 45 23 5.8 3.2 | -11.1 12.0 310 50 26 4.6 2.5
14500 -12.9 8.8 305 46 24 6.2 3.4 | -10.4 13.3 310 49 25 4.7 2.6
14000 -12.0 10.4 305 48 25 6.1 3.4 | -9.7 14.5 310 47 24 4.4 2.4
13500 -10.7 12.7 300 47 24 5.8 3.2 | -9.2 15.4 305 44 23 4.0 2.2
13000 -9.9 14.2 300 47 24 6.1 3.3 | -8.2 17.2 305 40 20 4.7 2.6
12500 -8.9 16.0 295 47 24 6.2 3.4 | -7.6 18.3 300 37 19 4.6 2.6
12000 -8.0 17.6 295 47 24 6.8 3.7 | -6.8 19.8 295 36 18 6.3 3.5
11500 -7.0 19.4 295 46 23 7.0 3.8 | -5.8 21.6 295 35 18 6.6 3.6
11000 -6.0 21.2 295 44 23 7.3 4.0 | -4.9 23.2 295 35 18 5.8 3.2
10500 -4.9 23.2 295 42 21 8.1 4.5 | -4.1 24.6 290 33 17 6.4 3.5
10250 -4.4 24.1 295 40 21 4.0 2.2 | -3.7 25.3 290 32 16 3.1 1.7
10000 -4.2 24.4 290 40 21 4.8 2.6 | -3.5 25.7 290 32 16 4.0 2.2
9750 -3.6 25.5 295 38 20 10.8 5.9 | -3.0 26.6 290 31 16 9.3 5.1
9500 -2.8 27.0 295 37 19 11.5 6.3 | -2.3 27.9 290 29 15 9.9 5.5
9250 -2.0 28.4 295 35 18 8.2 4.5 | -1.6 29.1 290 28 14 6.3 3.5
9000 -1.5 29.3 295 34 18 5.5 3.0 | -1.3 29.7 290 27 14 4.2 2.3
8750 -1.0 30.2 295 33 17 9.4 5.2 | -0.8 30.6 290 25 13 9.9 5.4
8500 -0.2 31.6 295 31 16 10.9 6.0 | 0.0 32.0 290 23 12 10.8 5.9
8250 0.5 32.9 300 30 15 7.9 4.3 | 0.7 33.3 290 22 11 6.9 3.8
8000 1.0 33.8 300 28 15 5.7 3.1 | 1.1 34.0 295 21 11 5.0 2.7
7750 1.5 34.7 300 27 14 9.6 5.3 | 1.6 34.9 295 19 10 10.4 5.7
7500 2.3 36.1 300 25 13 9.2 5.0 | 2.5 36.5 300 17 9 9.8 5.4
7250 2.8 37.0 305 23 12 5.3 2.9 | 3.0 37.4 305 16 8 5.3 2.9
7000 3.2 37.8 305 20 10 3.9 2.1 | 3.4 38.1 310 15 8 5.4 3.0
6750 3.5 38.3 310 18 9 8.8 4.9 | 3.9 39.0 315 14 7 9.0 4.9
6500 4.4 39.9 310 15 8 10.1 5.6 | 4.7 40.5 320 12 6 9.2 5.1
6250 4.9 40.8 315 14 7 6.5 3.6 | 5.1 41.2 330 10 5 5.2 2.9
6000 5.5 41.9 320 12 6 6.6 3.6 | 5.6 42.1 340 8 4 6.7 3.7
5750 6.0 42.8 320 11 6 9.8 5.4 | 5.9 42.6 350 7 4 -0.3 -0.2
5500 7.0 44.6 325 9 5 17.5 9.6 | 5.4 41.7 005 5 2 -12.2 -6.7
________________________________________________________________________________
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 NEAR THE OLD STAPLETON
AIRPORT SITE IN DENVER, COLORADO AT
NORTH LATITUDE: 39 DEG 46 MIN 5.016 SEC
WEST LONGITUDE: 104 DEG 52 MIN 9.984 SEC
ELEVATION: 5285 FEET (1611 METERS)
AND MAY NOT BE REPRESENTATIVE OF OTHER AREAS ALONG THE FRONT RANGE OF THE
COLORADO ROCKY MOUNTAINS. 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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