613
UXUS97 KBOU 150114
SRGBOU
SOARING FORECAST
NATIONAL WEATHER SERVICE DENVER/BOULDER, COLORADO
1913 MDT SATURDAY, MARCH 14, 2026
THIS FORECAST IS FOR SUNDAY, MARCH 15, 2026:
IF THE TRIGGER TEMPERATURE OF 30.3 F/-1.0 C IS REACHED...THEN
THERMAL SOARING INDEX....................... POOR
MAXIMUM RATE OF LIFT........................ 231 FT/MIN (1.2 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 11121 FT MSL (5761 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 34.0 F/1.6 C
TIME OF TRIGGER TEMPERATURE.................... 1230 MDT
TIME OF OVERDEVELOPMENT........................ 1400 MDT
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... BROKEN/OVERCAST THIN MIDDLE
SURFACE WINDS DURING SOARING WINDOW............ BETWEEN 20 MPH AND 30 MPH
HEIGHT OF THE -3 THERMAL INDEX................. 8439 FT MSL (3079 FT AGL)
THERMAL SOARING OUTLOOK FOR MONDAY 03/16....... FAIR
WAVE SOARING INDEX............................. POOR
WAVE SOARING INDEX TREND (TO 1800 MDT)......... DECREASING
HEIGHT OF STABLE LAYER (12-18K FT MSL)......... NONE
WEAK PVA/NVA (THROUGH 1800 MDT)................ NEITHER
POTENTIAL HEIGHT OF WAVE....................... 26307 FT MSL (20947 FT AGL)
WAVE SOARING OUTLOOK FOR MONDAY 03/16.......... POOR
REMARKS... MUCH COOLER, BUT STILL WINDY ON SUNDAY
SUNRISE/SUNSET.................... 07:10:17 / 19:06:16 MDT
TOTAL POSSIBLE SUNSHINE........... 11 HR 55 MIN 59 SEC (715 MIN 59 SEC)
ALTITUDE OF SUN AT 13:08:17 MDT... 48.28 DEGREES
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 03/15/2026 AT 0600 MDT
FREEZING LEVEL.................. ENTIRE AIRMASS BELOW 32 F / 0 C
CONVECTIVE CONDENSATION LEVEL... 11788 FT MSL (6428 FT AGL)
LIFTED CONDENSATION LEVEL....... 11560 FT MSL (6201 FT AGL)
LIFTED INDEX.................... +11.6
K INDEX......................... +5.8
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 -54.6 -66.3 295 43 22 2.4 1.3 M M M M M
45000 -51.0 -59.8 300 54 28 2.4 1.3 M M M M M
40000 -49.3 -56.7 300 62 32 1.0 0.5 M M M M M
38000 -48.5 -55.3 305 66 34 2.4 1.3 M M M M M
36000 -47.1 -52.8 305 71 37 2.3 1.3 M M M M M
34000 -45.7 -50.3 305 77 40 2.3 1.3 M M M M M
32000 -44.3 -47.7 310 79 41 2.2 1.2 M M M M M
30000 -43.0 -45.4 310 81 42 2.2 1.2 M M M M M
29000 -42.3 -44.1 310 82 42 2.5 1.4 34.0 93.2 24.7 M M
28000 -41.6 -42.9 310 83 43 2.5 1.4 31.0 87.8 22.8 M M
27000 -40.8 -41.4 310 85 44 2.5 1.4 28.2 82.7 20.9 M M
26000 -40.1 -40.2 310 86 44 2.8 1.5 25.6 78.0 19.1 M M
25000 -39.1 -38.4 310 86 44 3.5 1.9 23.0 73.4 17.3 M M
24000 -38.0 -36.4 310 86 44 3.5 1.9 20.6 69.1 15.6 M M
23000 -37.0 -34.6 310 86 44 3.3 1.8 18.4 65.1 14.0 M M
22000 -36.2 -33.2 310 79 41 2.6 1.4 15.7 60.3 12.0 M M
21000 -35.2 -31.4 310 69 35 2.7 1.5 12.5 54.5 9.5 M M
20000 -34.2 -29.6 305 60 31 4.2 2.3 10.2 50.4 7.7 M M
19500 -33.6 -28.5 305 57 29 4.2 2.3 9.2 48.5 6.8 M M
19000 -33.0 -27.4 305 53 27 4.2 2.3 8.2 46.7 6.0 M M
18500 -32.4 -26.3 305 49 25 4.3 2.3 7.2 45.0 5.2 M M
18000 -31.7 -25.1 305 45 23 5.3 2.9 6.3 43.3 4.4 M M
17500 -30.7 -23.3 305 43 22 7.6 4.2 5.8 42.5 4.0 M M
17000 -29.6 -21.3 305 41 21 7.5 4.1 5.5 41.9 3.7 M M
16500 -28.3 -18.9 305 39 20 8.8 4.8 5.2 41.4 3.5 M M
16000 -27.0 -16.6 305 37 19 8.7 4.8 5.0 41.0 3.4 M M
15500 -25.8 -14.4 305 35 18 8.2 4.5 4.8 40.7 3.2 M M
15000 -24.6 -12.3 305 34 17 8.1 4.5 4.5 40.2 2.9 M M
14500 -23.4 -10.1 305 32 17 7.9 4.3 4.3 39.7 2.7 M M
14000 -22.2 -8.0 305 31 16 7.8 4.3 3.9 39.1 2.4 M M
13500 -21.1 -6.0 310 29 15 7.5 4.1 3.6 38.5 2.1 M M
13000 -20.0 -4.0 315 28 15 7.3 4.0 3.2 37.8 1.7 M M
12500 -18.9 -2.0 315 28 14 7.0 3.8 2.8 37.0 1.4 M M
12000 -17.9 -0.2 320 28 15 6.8 3.7 2.3 36.1 0.9 M M
11500 -16.9 1.6 325 29 15 6.4 3.5 1.8 35.3 0.4 M M
11000 -16.0 3.2 330 31 16 6.3 3.4 1.2 34.2 -0.1 423 2.2
10500 -15.1 4.8 335 32 17 5.9 3.2 0.7 33.2 -0.6 381 1.9
10250 -14.6 5.7 335 33 17 5.7 3.1 0.4 32.6 -0.9 361 1.8
10000 -14.2 6.4 335 34 18 6.1 3.4 0.0 32.1 -1.2 340 1.7
9750 -13.7 7.3 340 35 18 6.5 3.6 -0.2 31.6 -1.5 318 1.6
9500 -13.2 8.2 340 36 19 6.1 3.4 -0.5 31.1 -1.8 297 1.5
9250 -12.8 9.0 345 38 19 5.9 3.2 -0.8 30.6 -2.1 276 1.4
9000 -12.3 9.9 345 39 20 6.0 3.3 -1.1 30.0 -2.3 255 1.3
8750 -11.9 10.6 350 40 20 6.4 3.5 -1.4 29.5 -2.6 234 1.2
8500 -11.4 11.5 350 40 21 6.7 3.7 -1.6 29.1 -2.9 212 1.1
8250 -10.9 12.4 350 40 21 6.4 3.5 -1.9 28.6 -3.1 190 1.0
8000 -10.4 13.3 355 40 21 7.1 3.9 -2.1 28.2 -3.4 168 0.9
7750 -9.8 14.4 355 39 20 8.3 4.6 -2.2 28.0 -3.5 143 0.7
7500 -9.2 15.4 355 39 20 8.5 4.7 -2.3 27.8 -3.6 116 0.6
7250 -8.6 16.5 355 38 20 8.7 4.8 -2.4 27.6 -3.7 90 0.5
7000 -7.9 17.8 355 37 19 9.2 5.0 -2.5 27.5 -3.8 62 0.3
6750 -7.2 19.0 360 36 19 9.6 5.3 -2.5 27.4 -3.9 34 0.2
6500 -6.5 20.3 360 35 18 9.8 5.4 -2.5 27.5 -3.9 5 0.0
6250 -5.7 21.7 360 33 17 10.4 5.7 -2.5 27.5 -3.9 M M
6000 -4.9 23.2 360 31 16 11.0 6.1 -2.4 27.6 -3.8 M M
5750 -4.1 24.6 360 29 15 10.3 5.6 -2.3 27.8 -3.7 M M
5500 -3.3 26.1 360 26 13 11.8 6.5 -2.3 27.9 -3.7 M M
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *
03/15/2026 AT 0900 MDT | 03/15/2026 AT 1200 MDT
|
CAPE... 0.0 LI... +3.9 | CAPE... +6.7 LI... +5.0
CINH... -0.0 K INDEX... -2.7 | 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 -54.2 -65.6 295 44 23 2.4 1.3 | -54.8 -66.6 300 43 22 2.4 1.3
45000 -50.5 -58.9 305 54 28 2.4 1.3 | -50.9 -59.6 310 58 30 2.4 1.3
40000 -48.5 -55.3 310 65 33 1.2 0.7 | -49.3 -56.7 310 71 37 1.0 0.5
38000 -47.8 -54.0 310 70 36 0.8 0.5 | -48.7 -55.7 315 76 39 1.2 0.6
36000 -47.3 -53.1 315 78 40 0.9 0.5 | -48.0 -54.4 320 83 43 1.1 0.6
34000 -46.7 -52.1 315 87 45 0.9 0.5 | -47.3 -53.1 325 91 47 1.1 0.6
32000 -45.7 -50.3 320 94 48 2.2 1.2 | -46.1 -51.0 325 102 53 2.0 1.1
30000 -44.3 -47.7 320 101 52 2.2 1.2 | -44.9 -48.8 330 114 58 2.0 1.1
29000 -43.5 -46.3 320 103 53 3.2 1.8 | -43.9 -47.0 330 116 60 4.6 2.5
28000 -42.5 -44.5 320 104 53 3.3 1.8 | -42.5 -44.5 330 115 59 4.6 2.5
27000 -41.5 -42.7 320 105 54 3.3 1.8 | -41.1 -42.0 325 114 59 4.6 2.5
26000 -40.5 -40.9 320 106 54 3.8 2.1 | -39.7 -39.5 325 113 58 4.5 2.5
25000 -39.2 -38.6 320 104 53 4.3 2.3 | -38.4 -37.1 325 110 57 4.5 2.5
24000 -38.0 -36.4 320 102 52 4.3 2.3 | -37.1 -34.8 325 106 55 4.5 2.5
23000 -36.7 -34.1 320 100 51 3.4 1.9 | -35.7 -32.3 320 103 53 3.4 1.9
22000 -36.0 -32.8 320 91 47 2.1 1.2 | -35.0 -31.0 320 95 49 2.3 1.3
21000 -35.4 -31.7 320 81 42 2.1 1.2 | -34.3 -29.7 320 88 45 2.3 1.3
20000 -34.7 -30.5 320 72 37 2.5 1.4 | -33.8 -28.8 325 79 41 0.7 0.4
19500 -34.3 -29.7 320 68 35 2.5 1.3 | -33.6 -28.5 320 74 38 0.9 0.5
19000 -34.0 -29.2 320 64 33 2.5 1.4 | -33.5 -28.3 320 69 36 0.9 0.5
18500 -33.6 -28.5 320 60 31 2.5 1.3 | -33.4 -28.1 320 64 33 0.9 0.5
18000 -33.1 -27.6 315 54 28 3.5 1.9 | -33.2 -27.8 320 57 29 1.9 1.0
17500 -32.4 -26.3 315 52 27 4.4 2.4 | -32.8 -27.0 315 53 27 2.6 1.4
17000 -31.8 -25.2 315 49 25 4.6 2.5 | -32.4 -26.3 315 49 25 3.3 1.8
16500 -30.9 -23.6 315 47 24 6.0 3.3 | -31.7 -25.1 310 45 23 5.9 3.2
16000 -30.1 -22.2 315 45 23 5.7 3.1 | -30.8 -23.4 310 42 22 5.7 3.1
15500 -29.0 -20.2 315 43 22 8.4 4.6 | -29.8 -21.6 310 40 21 8.2 4.5
15000 -27.8 -18.0 315 42 22 8.1 4.4 | -28.6 -19.5 310 38 19 7.9 4.4
14500 -26.6 -15.9 315 41 21 8.6 4.7 | -27.4 -17.3 310 36 18 8.1 4.5
14000 -25.3 -13.5 315 40 20 8.6 4.7 | -26.2 -15.2 310 34 18 8.1 4.5
13500 -24.0 -11.2 315 39 20 8.6 4.7 | -25.0 -13.0 315 33 17 7.7 4.2
13000 -22.7 -8.9 315 38 19 8.7 4.8 | -23.9 -11.0 315 31 16 7.8 4.3
12500 -21.5 -6.7 320 37 19 7.7 4.2 | -22.7 -8.9 320 30 16 7.6 4.1
12000 -20.4 -4.7 320 36 19 7.6 4.2 | -21.6 -6.9 325 30 15 7.5 4.1
11500 -19.3 -2.7 325 36 19 7.5 4.1 | -20.4 -4.7 330 29 15 7.8 4.3
11000 -18.1 -0.6 325 36 19 7.6 4.2 | -19.3 -2.7 335 28 14 7.8 4.3
10500 -17.0 1.4 330 37 19 6.8 3.7 | -18.0 -0.4 340 27 14 8.4 4.6
10250 -16.5 2.3 330 37 19 7.8 4.3 | -17.4 0.7 340 27 14 9.4 5.1
10000 -16.0 3.2 335 37 19 4.4 2.4 | -16.8 1.8 345 26 13 5.2 2.9
9750 -15.8 3.6 335 36 19 4.9 2.7 | -16.5 2.3 345 26 13 7.1 3.9
9500 -15.2 4.6 335 36 19 8.4 4.6 | -15.6 3.9 350 26 13 12.5 6.8
9250 -14.6 5.7 340 36 19 8.0 4.4 | -14.8 5.4 350 26 13 11.6 6.4
9000 -14.0 6.8 340 37 19 6.1 3.4 | -13.9 7.0 350 26 13 8.6 4.7
8750 -13.7 7.3 345 36 19 5.6 3.1 | -13.4 7.9 350 26 14 7.9 4.3
8500 -13.1 8.4 345 36 18 7.8 4.3 | -12.6 9.3 355 26 14 11.4 6.2
8250 -12.6 9.3 350 36 18 7.6 4.2 | -11.8 10.8 355 26 14 10.2 5.6
8000 -12.0 10.4 350 35 18 7.1 3.9 | -11.1 12.0 355 26 14 8.4 4.6
7750 -11.5 11.3 350 35 18 8.1 4.4 | -10.5 13.1 355 27 14 9.4 5.2
7500 -10.8 12.6 355 34 18 10.0 5.5 | -9.7 14.5 355 27 14 11.2 6.1
7250 -10.1 13.8 355 33 17 9.3 5.1 | -8.9 16.0 355 26 14 9.6 5.2
7000 -9.4 15.1 355 33 17 7.8 4.3 | -8.3 17.1 360 27 14 7.2 4.0
6750 -8.8 16.2 355 33 17 10.2 5.6 | -7.7 18.1 360 27 14 11.5 6.3
6500 -7.9 17.8 355 32 16 12.0 6.6 | -6.6 20.1 360 26 13 12.7 7.0
6250 -7.1 19.2 355 31 16 10.8 5.9 | -5.9 21.4 360 25 13 10.2 5.6
6000 -6.3 20.7 355 29 15 10.3 5.7 | -5.1 22.8 360 25 13 9.5 5.2
5750 -5.5 22.1 360 28 15 11.7 6.4 | -4.3 24.3 360 25 13 14.4 7.9
5500 -4.5 23.9 355 24 12 16.9 9.3 | -2.7 27.1 360 21 11 28.3 15.5
03/15/2026 AT 1500 MDT | 03/15/2026 AT 1800 MDT
|
CAPE... 0.0 LI... +3.5 | CAPE... 0.0 LI... +3.4
CINH... -0.1 K INDEX... -2.3 | CINH... -0.2 K INDEX... -1.2
|
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 -55.6 -68.1 310 46 24 1.9 1.0 | -55.9 -68.6 325 56 29 2.2 1.2
45000 -52.7 -62.9 320 66 34 1.9 1.0 | -52.5 -62.5 335 71 37 2.2 1.2
40000 -49.9 -57.8 325 76 39 1.8 1.0 | -51.8 -61.2 330 100 52 0.3 0.2
38000 -49.0 -56.2 325 82 42 -0.1 -0.0 | -51.6 -60.9 330 113 58 -0.4 -0.2
36000 -48.9 -56.0 330 95 49 0.1 0.0 | -51.9 -61.4 335 126 65 -0.4 -0.2
34000 -48.9 -56.0 335 109 56 0.2 0.1 | -52.1 -61.8 345 141 72 -0.4 -0.2
32000 -47.5 -53.5 335 122 63 3.2 1.8 | -48.7 -55.7 345 149 77 6.4 3.5
30000 -45.3 -49.5 335 136 70 3.0 1.7 | -44.9 -48.8 345 154 79 6.6 3.6
29000 -43.8 -46.8 335 137 71 5.9 3.3 | -42.6 -44.7 340 154 79 7.8 4.3
28000 -42.0 -43.6 335 135 69 6.0 3.3 | -40.3 -40.5 340 153 79 7.8 4.3
27000 -40.3 -40.5 335 133 68 6.0 3.3 | -37.9 -36.2 340 152 78 7.8 4.3
26000 -38.5 -37.3 335 130 67 5.1 2.8 | -35.8 -32.4 340 148 76 4.8 2.6
25000 -37.0 -34.6 330 124 64 5.0 2.7 | -34.3 -29.7 340 140 72 5.1 2.8
24000 -35.5 -31.9 330 119 61 5.0 2.7 | -32.8 -27.0 335 132 68 5.1 2.8
23000 -34.1 -29.4 325 113 58 2.6 1.4 | -31.4 -24.5 335 123 63 1.9 1.1
22000 -33.7 -28.7 325 103 53 1.5 0.8 | -30.9 -23.6 330 113 58 1.8 1.0
21000 -33.2 -27.8 320 93 48 1.5 0.8 | -30.3 -22.5 330 103 53 1.8 1.0
20000 -32.9 -27.2 320 82 42 -0.5 -0.2 | -30.2 -22.4 325 91 47 -1.8 -1.0
19500 -33.0 -27.4 320 75 39 -0.3 -0.2 | -30.5 -22.9 325 83 43 -1.7 -0.9
19000 -33.0 -27.4 315 68 35 -0.3 -0.1 | -30.7 -23.3 320 76 39 -1.7 -0.9
18500 -33.1 -27.6 315 61 32 -0.2 -0.1 | -31.1 -24.0 320 65 33 -2.0 -1.1
18000 -33.0 -27.4 305 52 27 4.0 2.2 | -31.1 -24.0 320 58 30 2.7 1.5
17500 -32.1 -25.8 305 49 25 5.6 3.1 | -30.6 -23.1 315 52 27 3.4 1.9
17000 -31.3 -24.3 300 47 24 6.4 3.5 | -30.2 -22.4 310 46 24 5.5 3.0
16500 -30.2 -22.4 300 44 23 7.8 4.3 | -29.0 -20.2 310 42 22 7.8 4.3
16000 -29.0 -20.2 300 41 21 7.8 4.3 | -27.8 -18.0 310 39 20 8.1 4.4
15500 -27.9 -18.2 300 39 20 8.0 4.4 | -26.6 -15.9 305 37 19 8.7 4.8
15000 -26.7 -16.1 300 36 19 8.0 4.4 | -25.3 -13.5 305 35 18 8.7 4.8
14500 -25.5 -13.9 300 34 17 7.3 4.0 | -24.0 -11.2 305 33 17 8.1 4.4
14000 -24.4 -11.9 305 31 16 7.4 4.0 | -22.8 -9.0 305 32 16 8.2 4.5
13500 -23.3 -9.9 305 29 15 7.4 4.1 | -21.6 -6.9 305 30 16 8.0 4.4
13000 -22.2 -8.0 310 26 14 7.4 4.0 | -20.4 -4.7 310 29 15 8.0 4.4
12500 -21.1 -6.0 315 24 12 7.5 4.1 | -19.2 -2.6 310 27 14 8.1 4.4
12000 -20.0 -4.0 320 21 11 7.5 4.1 | -18.0 -0.4 310 26 13 8.1 4.4
11500 -18.9 -2.0 325 19 10 7.8 4.3 | -16.8 1.8 310 24 13 8.0 4.4
11000 -17.7 0.1 330 18 9 7.8 4.3 | -15.6 3.9 315 23 12 8.0 4.4
10500 -16.4 2.5 335 17 9 9.1 5.0 | -14.4 6.1 315 21 11 8.2 4.5
10250 -15.7 3.7 335 17 9 9.7 5.3 | -13.8 7.2 315 20 10 9.1 5.0
10000 -15.0 5.0 340 16 8 6.9 3.8 | -13.2 8.2 320 19 10 5.5 3.0
9750 -14.6 5.7 340 16 8 7.8 4.3 | -12.9 8.8 320 18 9 6.2 3.4
9500 -13.8 7.2 340 16 8 11.2 6.1 | -12.1 10.2 320 17 9 10.2 5.6
9250 -13.0 8.6 345 16 8 10.7 5.9 | -11.4 11.5 325 16 8 9.3 5.1
9000 -12.2 10.0 345 16 8 8.9 4.9 | -10.7 12.7 325 15 8 8.6 4.7
8750 -11.6 11.1 345 16 8 8.8 4.8 | -10.1 13.8 325 14 7 8.5 4.6
8500 -10.9 12.4 350 16 8 11.0 6.0 | -9.4 15.1 330 14 7 9.5 5.2
8250 -10.1 13.8 350 16 8 10.2 5.6 | -8.8 16.2 330 13 7 9.1 5.0
8000 -9.3 15.3 350 16 8 9.6 5.3 | -8.1 17.4 335 13 6 8.6 4.7
7750 -8.6 16.5 355 16 8 9.7 5.3 | -7.4 18.7 335 12 6 8.9 4.9
7500 -7.9 17.8 355 16 8 10.2 5.6 | -6.7 19.9 340 12 6 9.5 5.2
7250 -7.1 19.2 355 15 8 9.9 5.4 | -6.0 21.2 340 11 6 9.4 5.2
7000 -6.4 20.5 355 15 8 9.5 5.2 | -5.3 22.5 345 11 6 9.2 5.1
6750 -5.7 21.7 360 15 8 10.1 5.6 | -4.6 23.7 345 10 5 9.8 5.4
6500 -4.9 23.2 360 15 8 10.7 5.9 | -3.9 25.0 350 10 5 10.2 5.6
6250 -4.1 24.6 360 15 7 10.8 5.9 | -3.1 26.4 355 10 5 9.9 5.5
6000 -3.3 26.1 005 14 7 10.0 5.5 | -2.4 27.7 355 9 5 9.6 5.3
5750 -2.5 27.5 005 14 7 12.8 7.0 | -1.7 28.9 360 9 5 11.0 6.0
5500 -1.2 29.8 005 13 6 22.1 12.1 | -0.7 30.7 005 8 4 15.1 8.3
________________________________________________________________________________
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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