362
UXUS97 KBOU 281300
SRGBOU
SOARING FORECAST
NATIONAL WEATHER SERVICE DENVER/BOULDER, COLORADO
0700 MDT MONDAY, APRIL 28, 2025
THIS FORECAST IS FOR MONDAY, APRIL 28, 2025:
IF THE TRIGGER TEMPERATURE OF 54.5 F/12.5 C IS REACHED...THEN
THERMAL SOARING INDEX....................... EXCELLENT
MAXIMUM RATE OF LIFT........................ 957 FT/MIN (4.9 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 19706 FT MSL (14396 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 65.0 F/18.8 C
TIME OF TRIGGER TEMPERATURE.................... 0945 MDT
TIME OF OVERDEVELOPMENT........................ NONE
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... BROKEN/OVERCAST OPAQUE MIDDLE
SURFACE WINDS DURING SOARING WINDOW............ 20 MPH OR LESS
HEIGHT OF THE -3 THERMAL INDEX................. 14218 FT MSL (8907 FT AGL)
THERMAL SOARING OUTLOOK FOR TUESDAY 04/29...... FAIR
WAVE SOARING INDEX............................. POOR
WAVE SOARING INDEX TREND (TO 1800 MDT)......... LITTLE CHANGE
HEIGHT OF STABLE LAYER (12-18K FT MSL)......... NONE
WEAK PVA/NVA (THROUGH 1800 MDT)................ WEAK PVA
POTENTIAL HEIGHT OF WAVE....................... 34129 FT MSL (28819 FT AGL)
WAVE SOARING OUTLOOK FOR TUESDAY 04/29......... POOR
REMARKS... A FEW SHOWERS TODAY, COOLER
SUNRISE/SUNSET.................... 06:02:54 / 19:50:53 MDT
TOTAL POSSIBLE SUNSHINE........... 13 HR 47 MIN 59 SEC (827 MIN 59 SEC)
ALTITUDE OF SUN AT 12:56:54 MDT... 64.64 DEGREES
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 04/28/2025 AT 0600 MDT
FREEZING LEVEL.................. 9542 FT MSL (4232 FT AGL)
CONVECTIVE CONDENSATION LEVEL... 12917 FT MSL (7607 FT AGL)
LIFTED CONDENSATION LEVEL....... 14545 FT MSL (9235 FT AGL)
LIFTED INDEX.................... -2.7
K INDEX......................... +18.1
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 -54.2 -65.6 235 32 16 2.0 1.1 M M M M M
45000 -51.2 -60.2 240 51 26 0.6 0.3 M M M M M
40000 -51.8 -61.2 225 68 35 -0.4 -0.2 M M M M M
38000 -51.1 -60.0 220 75 39 3.2 1.8 M M M M M
36000 -49.2 -56.6 220 82 42 3.2 1.8 M M M M M
34000 -46.9 -52.4 220 89 46 4.6 2.5 M M M M M
32000 -44.2 -47.6 220 87 45 4.5 2.5 M M M M M
30000 -41.5 -42.7 225 84 43 4.5 2.5 35.9 96.6 13.2 M M
29000 -40.2 -40.4 225 80 41 4.4 2.4 33.6 92.5 11.6 M M
28000 -38.9 -38.0 225 77 40 4.4 2.4 31.5 88.7 10.1 M M
27000 -37.5 -35.5 230 74 38 4.5 2.4 29.6 85.3 8.8 M M
26000 -36.2 -33.2 230 66 34 4.2 2.3 27.5 81.4 7.2 M M
25000 -35.0 -31.0 230 56 29 4.2 2.3 25.3 77.6 5.6 M M
24000 -33.7 -28.7 230 46 24 4.2 2.3 23.3 74.0 4.0 M M
23000 -32.1 -25.8 230 38 20 6.5 3.5 21.8 71.2 2.8 M M
22000 -30.1 -22.2 225 32 17 6.5 3.6 20.5 69.0 1.8 M M
21000 -28.2 -18.8 220 26 14 6.5 3.5 19.5 67.0 0.9 M M
20000 -25.9 -14.6 220 22 11 8.1 4.4 18.7 65.6 0.2 M M
19500 -24.7 -12.5 220 21 11 8.1 4.4 18.4 65.1 -0.1 1346 6.8
19000 -23.5 -10.3 215 19 10 8.1 4.4 18.1 64.6 -0.3 1295 6.6
18500 -22.3 -8.1 215 17 9 8.1 4.5 17.8 64.1 -0.5 1245 6.3
18000 -21.1 -6.0 210 16 8 7.9 4.3 17.6 63.6 -0.8 1194 6.1
17500 -19.4 -2.9 210 14 7 7.9 4.3 17.1 62.8 -1.3 1119 5.7
17000 -18.2 -0.8 210 13 7 8.1 4.4 16.8 62.2 -1.5 1069 5.4
16500 -17.0 1.4 210 12 6 8.0 4.4 16.5 61.7 -1.8 1018 5.2
16000 -15.8 3.6 210 11 6 8.1 4.5 16.2 61.2 -2.1 968 4.9
15500 -14.6 5.7 210 11 6 8.2 4.5 15.9 60.7 -2.4 917 4.7
15000 -13.4 7.9 210 11 5 8.2 4.5 15.7 60.3 -2.6 866 4.4
14500 -12.1 10.2 210 11 5 8.3 4.5 15.4 59.8 -2.9 814 4.1
14000 -10.9 12.4 215 10 5 8.3 4.6 15.2 59.4 -3.1 762 3.9
13500 -9.7 14.5 220 10 5 8.4 4.6 15.0 58.9 -3.4 711 3.6
13000 -8.4 16.9 225 11 5 8.3 4.6 14.7 58.5 -3.6 659 3.3
12500 -7.2 19.0 235 11 6 8.1 4.4 14.5 58.1 -3.9 608 3.1
12000 -6.0 21.2 245 12 6 8.1 4.4 14.2 57.6 -4.2 557 2.8
11500 -4.8 23.4 255 13 6 8.2 4.5 14.0 57.1 -4.5 506 2.6
11000 -3.6 25.5 265 14 7 8.0 4.4 13.7 56.7 -4.8 455 2.3
10500 -2.6 27.3 270 15 8 6.4 3.5 13.3 55.9 -5.2 409 2.1
10250 -2.1 28.2 275 15 8 7.2 4.0 13.0 55.5 -5.4 387 2.0
10000 -1.4 29.5 280 16 8 11.5 6.3 13.0 55.4 -5.5 359 1.8
9750 -0.5 31.1 280 16 8 10.7 5.9 13.2 55.7 -5.4 325 1.6
9500 0.1 32.2 285 16 8 7.6 4.2 13.1 55.5 -5.5 299 1.5
9250 0.7 33.3 285 16 8 8.7 4.8 13.0 55.3 -5.6 273 1.4
9000 1.3 34.3 290 17 9 7.3 4.0 12.9 55.1 -5.8 247 1.3
8750 1.8 35.2 295 17 9 7.6 4.2 12.6 54.7 -6.0 225 1.1
8500 2.5 36.5 295 17 9 9.1 5.0 12.5 54.6 -6.1 198 1.0
8250 3.1 37.6 295 17 9 8.7 4.8 12.5 54.4 -6.2 171 0.9
8000 3.7 38.7 300 17 9 6.8 3.7 12.4 54.2 -6.3 146 0.7
7750 4.2 39.6 300 18 9 6.8 3.8 12.1 53.7 -6.6 125 0.6
7500 4.8 40.6 305 17 9 8.9 4.9 12.0 53.5 -6.8 100 0.5
7250 5.4 41.7 305 17 9 7.0 3.8 11.8 53.3 -6.9 74 0.4
7000 5.8 42.4 305 17 9 3.6 2.0 11.5 52.7 -7.3 55 0.3
6750 6.0 42.8 310 17 9 5.8 3.2 11.0 51.9 -7.8 40 0.2
6500 6.6 43.9 310 15 8 8.7 4.8 10.9 51.6 -8.0 15 0.1
6250 7.1 44.8 310 14 7 5.4 3.0 10.7 51.3 -8.2 M M
6000 7.4 45.3 320 13 7 2.5 1.4 10.3 50.5 -8.7 M M
5750 7.6 45.7 325 12 6 6.1 3.4 9.8 49.6 -9.2 M M
5500 8.2 46.8 320 9 5 8.6 4.7 9.7 49.4 -9.4 M M
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *
04/28/2025 AT 0900 MDT | 04/28/2025 AT 1200 MDT
|
CAPE... +30.8 LI... +0.2 | CAPE... +76.5 LI... -0.8
CINH... -30.8 K INDEX... +13.7 | CINH... -4.6 K INDEX... +15.1
|
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 -53.4 -64.1 230 30 15 1.6 0.9 | -54.0 -65.2 220 27 14 1.9 1.0
45000 -51.0 -59.8 235 50 26 0.2 0.1 | -51.2 -60.2 235 43 22 0.3 0.2
40000 -52.2 -62.0 225 64 33 -0.8 -0.4 | -51.9 -61.4 225 60 31 -0.5 -0.3
38000 -51.6 -60.9 225 70 36 3.4 1.8 | -51.2 -60.2 225 66 34 3.3 1.8
36000 -49.6 -57.3 225 76 39 3.3 1.8 | -49.2 -56.6 225 70 36 3.3 1.8
34000 -47.2 -53.0 225 81 42 5.5 3.0 | -46.9 -52.4 230 75 39 4.5 2.5
32000 -44.0 -47.2 225 84 43 5.3 2.9 | -44.3 -47.7 230 79 41 4.3 2.4
30000 -40.9 -41.6 230 86 44 4.9 2.7 | -41.7 -43.1 235 82 42 5.1 2.8
29000 -39.4 -38.9 230 84 43 4.8 2.7 | -40.1 -40.2 235 78 40 5.0 2.8
28000 -38.0 -36.4 230 82 42 4.8 2.7 | -38.6 -37.5 235 75 39 5.0 2.8
27000 -36.5 -33.7 230 79 41 4.8 2.6 | -37.1 -34.8 235 72 37 5.0 2.7
26000 -35.0 -31.0 235 76 39 5.0 2.8 | -35.5 -31.9 235 67 35 5.7 3.1
25000 -33.5 -28.3 235 71 36 5.0 2.8 | -33.8 -28.8 240 63 32 5.7 3.1
24000 -32.0 -25.6 235 66 34 5.0 2.8 | -32.1 -25.8 240 58 30 5.7 3.2
23000 -30.5 -22.9 235 57 29 5.1 2.8 | -30.6 -23.1 245 49 25 4.3 2.3
22000 -29.0 -20.2 235 45 23 5.1 2.8 | -29.3 -20.7 250 38 19 4.3 2.3
21000 -27.5 -17.5 235 33 17 5.0 2.7 | -28.1 -18.6 255 26 14 4.2 2.3
20000 -25.7 -14.3 235 25 13 6.3 3.5 | -26.1 -15.0 260 21 11 7.1 3.9
19500 -24.7 -12.5 235 22 12 6.3 3.5 | -25.1 -13.2 265 19 10 7.1 3.9
19000 -23.8 -10.8 235 20 10 6.3 3.5 | -24.0 -11.2 265 16 8 7.1 3.9
18500 -22.9 -9.2 240 17 9 6.3 3.4 | -23.0 -9.4 270 15 7 7.0 3.8
18000 -21.3 -6.3 240 14 7 7.1 3.9 | -21.3 -6.3 275 13 7 8.1 4.4
17500 -20.3 -4.5 245 13 7 7.1 3.9 | -20.1 -4.2 275 13 7 8.1 4.5
17000 -19.2 -2.6 250 13 7 7.3 4.0 | -18.8 -1.8 275 13 7 8.6 4.7
16500 -18.2 -0.8 260 12 6 7.2 4.0 | -17.5 0.5 275 13 7 8.6 4.7
16000 -17.1 1.2 265 12 6 7.7 4.2 | -16.3 2.7 275 13 7 8.7 4.8
15500 -15.9 3.4 275 13 6 7.8 4.3 | -15.0 5.0 275 13 7 8.7 4.8
15000 -14.8 5.4 285 13 7 8.1 4.4 | -13.7 7.3 280 13 7 8.6 4.7
14500 -13.5 7.7 285 14 7 8.4 4.6 | -12.4 9.7 280 12 6 8.6 4.7
14000 -12.3 9.9 290 14 7 8.4 4.6 | -11.1 12.0 280 12 6 8.7 4.7
13500 -11.0 12.2 295 15 8 8.6 4.7 | -9.8 14.4 280 12 6 8.8 4.8
13000 -9.7 14.5 295 15 8 8.5 4.7 | -8.5 16.7 280 12 6 8.9 4.9
12500 -8.5 16.7 300 15 8 8.3 4.6 | -7.2 19.0 280 12 6 9.0 4.9
12000 -7.2 19.0 300 16 8 8.3 4.6 | -5.9 21.4 285 12 6 9.0 4.9
11500 -6.0 21.2 300 16 8 8.4 4.6 | -4.5 23.9 280 12 6 8.9 4.9
11000 -4.8 23.4 300 16 8 8.2 4.5 | -3.2 26.2 280 12 6 8.6 4.7
10500 -3.7 25.3 300 16 8 6.8 3.7 | -2.0 28.4 280 12 6 7.1 3.9
10250 -3.2 26.2 300 17 9 7.1 3.9 | -1.5 29.3 280 12 6 9.1 5.0
10000 -2.5 27.5 300 17 9 11.3 6.2 | -0.7 30.7 280 13 7 12.3 6.7
9750 -1.6 29.1 300 16 8 11.2 6.2 | 0.2 32.4 280 13 7 10.9 6.0
9500 -0.9 30.4 300 16 8 8.0 4.4 | 1.0 33.8 280 13 6 9.3 5.1
9250 -0.3 31.5 305 16 8 9.5 5.2 | 1.7 35.1 280 12 6 10.0 5.5
9000 0.4 32.7 305 16 8 6.8 3.7 | 2.4 36.3 280 12 6 8.8 4.8
8750 0.8 33.4 305 17 9 7.1 3.9 | 3.1 37.6 280 12 6 9.3 5.1
8500 1.5 34.7 300 16 8 9.8 5.4 | 3.8 38.8 280 12 6 10.8 5.9
8250 2.2 36.0 300 16 8 8.8 4.8 | 4.6 40.3 280 12 6 10.2 5.6
8000 2.7 36.9 300 16 8 6.3 3.4 | 5.3 41.5 280 11 6 9.0 5.0
7750 3.1 37.6 300 15 8 6.7 3.7 | 6.0 42.8 280 11 6 9.6 5.3
7500 3.7 38.7 300 14 7 8.9 4.9 | 6.8 44.2 280 11 6 11.0 6.0
7250 4.3 39.7 295 13 6 7.7 4.2 | 7.6 45.7 280 11 6 9.7 5.3
7000 4.8 40.6 295 12 6 6.0 3.3 | 8.2 46.8 280 11 6 8.0 4.4
6750 5.3 41.5 295 11 6 9.3 5.1 | 8.9 48.0 280 10 5 10.5 5.8
6500 6.2 43.2 295 11 6 12.1 6.6 | 9.8 49.6 280 10 5 12.8 7.0
6250 7.0 44.6 295 10 5 10.0 5.5 | 10.7 51.3 280 10 5 10.8 5.9
6000 7.7 45.9 295 10 5 9.1 5.0 | 11.5 52.7 280 10 5 10.1 5.6
5750 8.4 47.1 300 9 5 10.1 5.6 | 12.2 54.0 280 9 5 9.7 5.3
5500 9.3 48.7 295 9 4 15.4 8.4 | 13.1 55.6 280 9 5 16.8 9.2
04/28/2025 AT 1500 MDT | 04/28/2025 AT 1800 MDT
|
CAPE... +67.2 LI... -0.6 | CAPE... +134.9 LI... -1.0
CINH... -6.4 K INDEX... +16.0 | CINH... -13.6 K INDEX... +20.8
|
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 -54.5 -66.1 230 28 14 1.8 1.0 | -54.4 -65.9 225 29 15 0.7 0.4
45000 -51.9 -61.4 240 39 20 0.4 0.2 | -53.3 -63.9 235 37 19 1.0 0.5
40000 -52.1 -61.8 225 56 29 -0.1 -0.1 | -51.7 -61.1 230 48 25 1.1 0.6
38000 -51.3 -60.3 225 61 31 3.2 1.8 | -50.6 -59.1 230 51 26 2.5 1.4
36000 -49.3 -56.7 225 63 32 3.2 1.8 | -49.2 -56.6 230 51 26 2.5 1.4
34000 -47.2 -53.0 230 66 34 3.0 1.7 | -47.7 -53.9 230 51 26 1.8 1.0
32000 -45.3 -49.5 230 68 35 3.0 1.7 | -46.7 -52.1 235 53 28 1.5 0.8
30000 -43.3 -45.9 235 69 36 5.6 3.0 | -45.5 -49.9 240 55 29 5.7 3.2
29000 -41.8 -43.2 235 67 35 5.2 2.9 | -43.9 -47.0 245 54 28 5.3 2.9
28000 -40.2 -40.4 240 65 34 5.2 2.9 | -42.3 -44.1 245 53 27 5.3 2.9
27000 -38.6 -37.5 240 64 33 5.2 2.8 | -40.7 -41.3 245 52 27 5.5 3.0
26000 -37.0 -34.6 240 58 30 5.7 3.1 | -38.7 -37.7 245 45 23 7.0 3.9
25000 -35.3 -31.5 245 50 26 5.7 3.1 | -36.6 -33.9 245 37 19 7.0 3.9
24000 -33.6 -28.5 245 43 22 5.6 3.1 | -34.5 -30.1 240 29 15 6.9 3.8
23000 -31.7 -25.1 250 35 18 6.7 3.7 | -32.1 -25.8 240 24 13 8.2 4.5
22000 -29.7 -21.5 250 27 14 6.7 3.7 | -29.7 -21.5 240 20 10 8.2 4.5
21000 -27.7 -17.9 255 19 10 6.9 3.8 | -27.3 -17.1 240 16 8 8.1 4.4
20000 -25.4 -13.7 255 16 8 7.7 4.2 | -24.9 -12.8 240 15 8 7.8 4.3
19500 -24.3 -11.7 255 14 7 7.7 4.2 | -23.8 -10.8 240 14 7 7.8 4.3
19000 -23.2 -9.8 260 13 7 7.7 4.2 | -22.6 -8.7 240 13 7 7.9 4.3
18500 -22.0 -7.6 260 12 6 7.8 4.3 | -21.4 -6.5 240 13 6 7.9 4.3
18000 -20.2 -4.4 260 11 6 8.5 4.6 | -20.2 -4.4 245 12 6 8.1 4.4
17500 -18.9 -2.0 260 11 6 8.5 4.7 | -19.0 -2.2 245 11 6 8.1 4.5
17000 -17.6 0.3 260 11 6 8.6 4.7 | -17.2 1.0 250 10 5 8.0 4.4
16500 -16.3 2.7 260 11 6 8.6 4.7 | -16.1 3.0 255 10 5 8.0 4.4
16000 -15.1 4.8 260 11 6 8.6 4.7 | -14.8 5.4 260 9 5 8.4 4.6
15500 -13.8 7.2 265 11 6 8.7 4.7 | -13.6 7.5 265 9 5 8.3 4.6
15000 -12.5 9.5 265 11 6 8.5 4.7 | -12.3 9.9 270 9 5 8.6 4.7
14500 -11.2 11.8 265 11 6 8.5 4.6 | -11.1 12.0 280 9 5 8.6 4.7
14000 -10.0 14.0 270 11 6 8.8 4.8 | -9.8 14.4 285 10 5 9.0 5.0
13500 -8.6 16.5 270 11 6 9.1 5.0 | -8.4 16.9 295 10 5 9.2 5.1
13000 -7.3 18.9 275 11 6 9.2 5.0 | -7.1 19.2 300 10 5 9.3 5.1
12500 -5.9 21.4 280 11 6 9.3 5.1 | -5.7 21.7 300 11 5 9.4 5.2
12000 -4.5 23.9 285 12 6 9.3 5.1 | -4.3 24.3 305 11 6 9.4 5.1
11500 -3.1 26.4 290 12 6 9.4 5.2 | -2.9 26.8 305 11 6 9.3 5.1
11000 -1.7 28.9 290 12 6 9.0 4.9 | -1.5 29.3 310 12 6 8.4 4.6
10500 -0.5 31.1 290 12 6 7.5 4.1 | -0.3 31.5 315 12 6 6.6 3.6
10250 0.2 32.4 295 13 6 10.9 6.0 | 0.2 32.4 315 12 6 11.8 6.5
10000 1.1 34.0 295 13 6 13.0 7.1 | 1.3 34.3 315 12 6 12.9 7.1
9750 2.0 35.6 295 13 6 10.0 5.5 | 2.0 35.6 315 13 7 8.3 4.6
9500 2.7 36.9 295 13 6 9.9 5.4 | 2.7 36.9 315 13 7 10.1 5.5
9250 3.4 38.1 295 13 7 9.3 5.1 | 3.4 38.1 315 13 7 7.6 4.2
9000 4.1 39.4 295 13 7 8.6 4.7 | 3.9 39.0 320 14 7 7.4 4.1
8750 4.8 40.6 295 13 7 9.9 5.4 | 4.6 40.3 320 14 7 10.1 5.5
8500 5.6 42.1 295 13 7 10.7 5.9 | 5.3 41.5 320 14 7 10.6 5.8
8250 6.3 43.3 295 13 7 10.1 5.5 | 6.1 43.0 320 14 7 9.1 5.0
8000 7.1 44.8 295 13 7 9.3 5.1 | 6.7 44.1 320 15 8 7.7 4.2
7750 7.8 46.0 295 13 7 9.9 5.4 | 7.3 45.1 320 15 8 9.4 5.2
7500 8.6 47.5 295 13 7 10.9 6.0 | 8.1 46.6 320 15 8 10.7 5.8
7250 9.3 48.7 300 13 6 9.4 5.2 | 8.8 47.8 320 15 8 8.6 4.7
7000 10.0 50.0 300 13 7 7.8 4.3 | 9.4 48.9 320 16 8 6.9 3.8
6750 10.6 51.1 300 13 7 10.6 5.8 | 10.0 50.0 320 16 8 10.7 5.9
6500 11.5 52.7 300 12 6 12.6 6.9 | 10.9 51.6 320 15 8 12.0 6.6
6250 12.4 54.3 300 12 6 10.6 5.8 | 11.7 53.1 320 15 8 9.4 5.2
6000 13.2 55.8 300 12 6 9.9 5.5 | 12.4 54.3 320 15 8 8.8 4.8
5750 13.9 57.0 300 12 6 9.8 5.4 | 13.0 55.4 320 15 8 9.9 5.4
5500 14.8 58.6 300 11 6 16.1 8.9 | 13.9 57.0 325 13 7 13.8 7.5
________________________________________________________________________________
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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