467
UXUS97 KBOU 211232
SRGBOU
SOARING FORECAST
NATIONAL WEATHER SERVICE DENVER/BOULDER, COLORADO
0531 MST THURSDAY, FEBRUARY 21, 2019
THIS FORECAST IS FOR THURSDAY, FEBRUARY 21, 2019:
IF THE TRIGGER TEMPERATURE OF 35.0 F/1.6 C IS REACHED...THEN
THERMAL SOARING INDEX....................... POOR
MAXIMUM RATE OF LIFT........................ 19 FT/MIN (0.1 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 8257 FT MSL (2972 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 31.0 F/-1.0 C
TIME OF TRIGGER TEMPERATURE.................... NONE
TIME OF OVERDEVELOPMENT........................ 1600 MST
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... OVERCAST OPAQUE HIGH
SURFACE WINDS DURING SOARING WINDOW............ 20 MPH OR LESS
HEIGHT OF THE -3 THERMAL INDEX................. 6904 FT MSL (1619 FT AGL)
THERMAL SOARING OUTLOOK FOR FRIDAY 02/22....... POOR
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 PVA
POTENTIAL HEIGHT OF WAVE....................... 29703 FT MSL (24418 FT AGL)
WAVE SOARING OUTLOOK FOR FRIDAY 02/22.......... POOR
REMARKS... NONE
SUNRISE/SUNSET.................... 06:43:58 / 17:42:12 MST
TOTAL POSSIBLE SUNSHINE........... 10 HR 58 MIN 14 SEC (658 MIN 14 SEC)
ALTITUDE OF SUN AT 12:13:05 MST... 39.68 DEGREES
UPPER AIR DATA FROM RAWINSONDE OBSERVATION TAKEN ON 02/21/2019 AT 0500 MST
FREEZING LEVEL.................. ENTIRE AIRMASS BELOW 32 F / 0 C
CONVECTIVE CONDENSATION LEVEL... 14031 FT MSL (8746 FT AGL)
LIFTED CONDENSATION LEVEL....... 11687 FT MSL (6401 FT AGL)
LIFTED INDEX.................... +11.3
K INDEX......................... +2.2
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 -50.7 -59.3 225 41 21 4.4 2.4 120.5 248.9 68.4 M M
45000 -51.4 -60.5 235 86 44 3.4 1.9 94.2 201.5 57.2 M M
40000 -53.6 -64.5 225 80 41 -2.9 -1.6 67.0 152.5 43.6 M M
38000 -55.3 -67.5 225 87 45 -2.7 -1.5 55.5 131.8 37.1 M M
36000 -56.6 -69.9 225 87 45 -0.1 -0.1 44.9 112.9 31.0 M M
34000 -56.7 -70.1 220 84 43 -0.1 -0.1 35.3 95.5 25.2 M M
32000 -57.8 -72.0 220 85 44 -0.5 -0.3 25.5 77.9 18.8 M M
30000 -55.1 -67.2 215 86 44 7.6 4.2 21.3 70.4 16.2 M M
29000 -52.7 -62.9 215 87 45 7.9 4.3 20.5 68.9 15.8 M M
28000 -50.4 -58.7 215 83 43 7.9 4.3 19.7 67.4 15.4 M M
27000 -48.0 -54.4 215 79 41 7.9 4.3 18.9 66.1 15.0 M M
26000 -45.6 -50.1 220 76 39 8.2 4.5 18.3 65.0 14.7 M M
25000 -43.2 -45.8 220 72 37 8.2 4.5 17.8 64.1 14.5 M M
24000 -40.7 -41.3 220 71 36 8.2 4.5 17.1 62.8 14.1 M M
23000 -38.3 -36.9 220 69 36 8.1 4.5 16.6 61.9 13.9 M M
22000 -35.9 -32.6 220 65 34 7.7 4.2 15.8 60.4 13.4 M M
21000 -33.6 -28.5 220 61 31 7.7 4.2 15.0 59.0 12.9 M M
20000 -31.3 -24.3 220 56 29 7.6 4.2 14.4 57.8 12.5 M M
19500 -30.4 -22.7 220 54 28 4.7 2.6 13.6 56.6 12.0 M M
19000 -29.7 -21.5 220 51 26 4.9 2.7 12.8 55.0 11.3 M M
18500 -29.0 -20.2 220 48 25 4.9 2.7 11.9 53.4 10.6 M M
18000 -28.2 -18.8 220 45 23 4.9 2.7 11.1 52.0 10.0 M M
17500 -27.5 -17.5 220 42 22 5.9 3.2 10.3 50.6 9.4 M M
17000 -26.1 -15.0 220 38 20 6.2 3.4 9.4 48.9 8.6 M M
16500 -25.1 -13.2 225 35 18 6.2 3.4 8.8 47.9 8.2 M M
16000 -24.2 -11.6 225 33 17 6.2 3.4 8.3 46.9 7.7 M M
15500 -23.3 -9.9 225 31 16 6.2 3.4 7.7 45.8 7.2 M M
15000 -22.4 -8.3 225 29 15 6.2 3.4 7.1 44.7 6.7 M M
14500 -21.4 -6.5 225 27 14 6.2 3.4 6.5 43.7 6.2 M M
14000 -20.5 -4.9 225 26 13 6.2 3.4 5.9 42.7 5.8 M M
13500 -19.6 -3.3 220 24 12 6.2 3.4 5.3 41.6 5.2 M M
13000 -18.6 -1.5 220 23 12 6.2 3.4 4.8 40.6 4.7 M M
12500 -17.7 0.1 215 24 12 6.2 3.4 4.1 39.5 4.2 M M
12000 -16.8 1.8 215 25 13 6.2 3.4 3.6 38.4 3.6 M M
11500 -15.9 3.4 205 23 12 6.3 3.4 3.0 37.3 3.1 M M
11000 -14.7 5.5 200 21 11 9.1 5.0 2.6 36.7 2.8 M M
10500 -13.3 8.1 190 20 10 8.9 4.9 2.5 36.5 2.7 M M
10250 -12.7 9.1 185 19 10 8.9 4.9 2.4 36.4 2.6 M M
10000 -12.0 10.4 180 19 10 8.6 4.7 2.4 36.3 2.6 M M
9750 -11.3 11.7 185 18 9 9.8 5.4 2.3 36.1 2.5 M M
9500 -10.7 12.7 190 16 8 6.2 3.4 2.2 36.0 2.5 M M
9250 -10.4 13.3 200 14 7 2.3 1.3 1.7 35.1 2.0 M M
9000 -10.2 13.6 210 13 7 3.3 1.8 1.2 34.2 1.5 M M
8750 -10.0 14.0 220 9 5 3.1 1.7 0.7 33.2 1.0 M M
8500 -9.7 14.5 245 6 3 3.2 1.7 0.1 32.3 0.5 M M
8250 -9.5 14.9 295 5 2 3.1 1.7 -0.4 31.3 -0.0 219 1.1
8000 -9.3 15.3 330 7 4 3.1 1.7 -0.9 30.4 -0.5 204 1.0
7750 -9.1 15.6 330 7 4 3.2 1.8 -1.4 29.5 -1.0 190 1.0
7500 -8.8 16.2 335 7 4 3.0 1.6 -1.9 28.6 -1.6 176 0.9
7250 -8.6 16.5 335 8 4 3.9 2.1 -2.4 27.7 -2.1 162 0.8
7000 -8.4 16.9 335 8 4 0.5 0.3 -2.9 26.8 -2.6 147 0.7
6750 -8.6 16.5 335 8 4 -5.8 -3.2 -3.9 25.0 -3.6 147 0.7
6500 -9.1 15.6 335 9 5 -6.7 -3.7 -5.2 22.7 -4.8 154 0.8
6250 -9.6 14.7 335 9 5 -7.2 -4.0 -6.4 20.4 -6.0 161 0.8
6000 -10.1 13.8 335 10 5 -4.1 -2.3 -7.7 18.2 -7.2 168 0.9
5750 -10.1 13.8 325 8 4 4.1 2.2 -8.4 16.9 -8.0 161 0.8
5500 -9.6 14.7 305 7 4 8.0 4.4 -8.6 16.5 -8.3 139 0.7
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *
02/21/2019 AT 0800 MST | 02/21/2019 AT 1100 MST
|
CAPE... 0.0 LI... +3.4 | CAPE... 0.0 LI... +3.7
CINH... 0.0 K INDEX... +8.6 | 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 -53.5 -64.3 220 27 14 1.0 0.5 | -53.2 -63.8 220 29 15 1.1 0.6
45000 -52.0 -61.6 225 37 19 1.0 0.5 | -51.5 -60.7 220 37 19 1.1 0.6
40000 -52.5 -62.5 220 40 21 -0.7 -0.4 | -52.3 -62.1 220 39 20 -1.1 -0.6
38000 -52.9 -63.2 220 41 21 -0.7 -0.4 | -52.9 -63.2 220 39 20 -1.1 -0.6
36000 -54.3 -65.7 215 42 21 -2.9 -1.6 | -54.1 -65.4 215 40 21 -2.0 -1.1
34000 -56.3 -69.3 215 43 22 -2.9 -1.6 | -55.3 -67.5 215 41 21 -2.0 -1.1
32000 -56.1 -69.0 215 43 22 3.2 1.8 | -55.0 -67.0 215 41 21 2.7 1.5
30000 -54.1 -65.4 210 42 22 3.2 1.8 | -53.4 -64.1 210 40 21 2.7 1.5
29000 -52.9 -63.2 210 42 22 7.5 4.1 | -52.4 -62.3 210 40 21 6.1 3.3
28000 -50.7 -59.3 210 41 21 7.5 4.1 | -50.5 -58.9 210 39 20 6.3 3.5
27000 -48.4 -55.1 210 39 20 7.5 4.1 | -48.6 -55.5 210 39 20 6.3 3.5
26000 -46.2 -51.2 210 38 20 7.6 4.1 | -46.7 -52.1 210 38 20 6.3 3.5
25000 -43.8 -46.8 210 36 19 7.9 4.3 | -44.6 -48.3 210 37 19 7.4 4.1
24000 -41.5 -42.7 210 34 18 7.9 4.3 | -42.4 -44.3 210 35 18 7.4 4.1
23000 -39.1 -38.4 210 32 16 7.8 4.3 | -40.1 -40.2 210 33 17 7.4 4.1
22000 -37.1 -34.8 210 30 15 6.7 3.7 | -37.8 -36.0 210 30 16 7.8 4.3
21000 -35.1 -31.2 210 28 14 6.7 3.7 | -35.5 -31.9 210 28 14 7.8 4.3
20000 -33.1 -27.6 215 26 13 6.4 3.5 | -32.6 -26.7 210 25 13 7.0 3.9
19500 -32.1 -25.8 215 25 13 6.3 3.4 | -31.6 -24.9 210 24 12 7.1 3.9
19000 -30.7 -23.3 215 23 12 6.3 3.4 | -30.5 -22.9 210 22 12 7.1 3.9
18500 -29.8 -21.6 215 22 11 6.3 3.4 | -29.4 -20.9 210 21 11 7.1 3.9
18000 -28.9 -20.0 215 20 10 6.4 3.5 | -28.4 -19.1 210 20 10 7.0 3.9
17500 -27.9 -18.2 210 19 10 6.9 3.8 | -27.4 -17.3 210 19 10 6.5 3.6
17000 -26.8 -16.2 210 18 9 6.9 3.8 | -26.4 -15.5 210 19 10 6.5 3.6
16500 -25.8 -14.4 210 17 9 7.2 4.0 | -25.4 -13.7 210 18 9 6.8 3.7
16000 -24.7 -12.5 210 16 8 7.2 4.0 | -24.4 -11.9 210 17 9 6.8 3.7
15500 -23.7 -10.7 205 16 8 7.2 4.0 | -23.4 -10.1 210 17 8 6.8 3.8
15000 -22.6 -8.7 205 15 8 7.2 4.0 | -22.4 -8.3 210 16 8 6.9 3.8
14500 -21.5 -6.7 205 15 8 7.2 3.9 | -21.4 -6.5 210 15 8 6.9 3.8
14000 -20.5 -4.9 205 14 7 7.1 3.9 | -20.3 -4.5 210 15 8 7.0 3.8
13500 -19.4 -2.9 200 14 7 7.1 3.9 | -19.3 -2.7 210 14 7 7.1 3.9
13000 -18.3 -0.9 200 13 7 7.1 3.9 | -18.2 -0.8 205 14 7 7.3 4.0
12500 -17.3 0.9 195 12 6 7.0 3.8 | -17.1 1.2 205 13 7 7.2 4.0
12000 -16.3 2.7 195 11 6 6.5 3.6 | -16.1 3.0 200 13 7 7.0 3.8
11500 -15.3 4.5 190 10 5 6.3 3.5 | -15.1 4.8 200 12 6 6.8 3.7
11000 -14.4 6.1 185 9 5 5.7 3.1 | -14.1 6.6 195 11 6 6.1 3.4
10500 -13.6 7.5 180 8 4 5.3 2.9 | -13.2 8.2 195 11 5 5.7 3.1
10250 -13.2 8.2 180 7 4 4.5 2.5 | -12.8 9.0 190 10 5 4.9 2.7
10000 -12.9 8.8 180 7 3 4.6 2.5 | -12.4 9.7 190 10 5 5.0 2.8
9750 -12.5 9.5 180 6 3 5.8 3.2 | -12.1 10.2 190 9 5 5.5 3.0
9500 -12.1 10.2 175 5 2 5.2 2.9 | -11.6 11.1 185 8 4 4.6 2.5
9250 -11.7 10.9 175 4 2 3.9 2.2 | -11.4 11.5 185 7 4 3.5 1.9
9000 -11.4 11.5 175 3 2 4.4 2.4 | -11.1 12.0 185 6 3 4.0 2.2
8750 -11.1 12.0 180 2 1 3.8 2.1 | -10.8 12.6 185 5 3 3.2 1.7
8500 -10.9 12.4 175 1 1 2.6 1.4 | -10.6 12.9 180 4 2 1.2 0.6
8250 -10.7 12.7 000 0 0 2.2 1.2 | -10.6 12.9 185 3 1 0.4 0.2
8000 -10.5 13.1 320 1 0 2.3 1.3 | -10.6 12.9 185 2 1 0.5 0.3
7750 -10.4 13.3 330 2 1 2.0 1.1 | -10.5 13.1 000 0 0 2.5 1.4
7500 -10.2 13.6 330 3 1 1.8 1.0 | -10.2 13.6 320 1 0 3.8 2.1
7250 -10.1 13.8 330 3 2 1.9 1.0 | -10.0 14.0 340 1 1 3.1 1.7
7000 -10.0 14.0 330 4 2 1.5 0.9 | -9.7 14.5 345 2 1 3.3 1.8
6750 -9.9 14.2 335 5 2 0.9 0.5 | -9.4 15.1 345 3 1 6.4 3.5
6500 -9.8 14.4 330 5 3 0.6 0.4 | -8.8 16.2 350 3 1 9.3 5.1
6250 -9.7 14.5 330 5 2 1.0 0.6 | -8.1 17.4 350 3 1 9.4 5.1
6000 -9.6 14.7 325 5 2 1.6 0.9 | -7.3 18.9 350 3 1 10.2 5.6
5750 -9.5 14.9 325 4 2 3.3 1.8 | -6.6 20.1 350 3 2 9.9 5.4
5500 -9.1 15.6 325 3 2 6.8 3.8 | -5.7 21.7 350 3 1 14.3 7.8
02/21/2019 AT 1400 MST | 02/21/2019 AT 1700 MST
|
CAPE... 0.0 LI... +2.5 | CAPE... +5.5 LI... +1.6
CINH... -0.0 K INDEX... +9.4 | CINH... -1.6 K INDEX... +13.0
|
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 -53.7 -64.7 225 33 17 0.2 0.1 | -54.0 -65.2 220 33 17 0.2 0.1
45000 -53.3 -63.9 220 40 20 0.2 0.1 | -53.7 -64.7 225 38 19 0.2 0.1
40000 -53.5 -64.3 220 43 22 -0.2 -0.1 | -54.7 -66.5 225 44 23 -0.9 -0.5
38000 -53.6 -64.5 220 44 23 -0.2 -0.1 | -55.2 -67.4 225 47 24 -1.0 -0.6
36000 -53.9 -65.0 220 44 23 -0.5 -0.3 | -54.7 -66.5 225 51 26 1.1 0.6
34000 -54.2 -65.6 220 44 23 -0.5 -0.3 | -54.0 -65.2 225 54 28 1.1 0.6
32000 -53.6 -64.5 220 42 22 2.2 1.2 | -52.5 -62.5 225 55 28 3.4 1.9
30000 -52.3 -62.1 220 41 21 2.2 1.2 | -50.5 -58.9 225 53 27 3.4 1.9
29000 -51.5 -60.7 220 40 20 5.1 2.8 | -49.4 -56.9 225 52 27 3.8 2.1
28000 -49.9 -57.8 220 38 20 5.2 2.8 | -48.3 -54.9 225 47 24 3.7 2.1
27000 -48.4 -55.1 220 37 19 5.2 2.8 | -47.2 -53.0 225 43 22 3.7 2.1
26000 -46.8 -52.2 220 36 18 5.3 2.9 | -46.1 -51.0 230 39 20 3.9 2.2
25000 -44.9 -48.8 220 34 18 6.5 3.6 | -44.5 -48.1 230 35 18 5.6 3.1
24000 -43.0 -45.4 220 33 17 6.5 3.6 | -42.8 -45.0 230 31 16 5.6 3.1
23000 -41.0 -41.8 220 31 16 6.6 3.6 | -41.1 -42.0 230 27 14 5.9 3.2
22000 -38.7 -37.7 220 29 15 8.0 4.4 | -38.9 -38.0 230 24 12 7.6 4.2
21000 -36.3 -33.3 220 26 13 8.0 4.4 | -36.6 -33.9 230 21 11 7.6 4.2
20000 -33.9 -29.0 220 23 12 7.9 4.3 | -33.7 -28.7 230 18 9 8.4 4.6
19500 -32.1 -25.8 220 22 11 7.9 4.3 | -32.4 -26.3 230 17 9 8.4 4.6
19000 -30.9 -23.6 220 21 11 7.9 4.3 | -31.2 -24.2 230 16 8 8.4 4.6
18500 -29.8 -21.6 220 20 10 7.9 4.3 | -29.9 -21.8 225 15 8 8.4 4.6
18000 -28.6 -19.5 220 19 10 7.9 4.3 | -28.7 -19.7 225 15 8 8.3 4.6
17500 -27.4 -17.3 220 19 10 7.9 4.3 | -27.5 -17.5 220 15 8 8.2 4.5
17000 -26.2 -15.2 220 18 9 8.0 4.4 | -26.3 -15.3 220 15 8 8.2 4.5
16500 -25.1 -13.2 215 18 9 7.6 4.2 | -25.1 -13.2 215 15 8 7.9 4.3
16000 -23.9 -11.0 215 17 9 7.7 4.2 | -23.9 -11.0 215 15 8 7.9 4.3
15500 -22.8 -9.0 215 17 9 7.4 4.1 | -22.7 -8.9 210 15 8 7.9 4.3
15000 -21.7 -7.1 215 17 9 7.3 4.0 | -21.5 -6.7 210 15 8 7.9 4.3
14500 -20.6 -5.1 215 17 9 7.4 4.0 | -20.4 -4.7 210 15 8 7.7 4.2
14000 -19.5 -3.1 215 16 8 7.4 4.1 | -19.3 -2.7 205 15 8 7.6 4.2
13500 -18.4 -1.1 215 16 8 7.3 4.0 | -18.1 -0.6 200 15 8 7.5 4.1
13000 -17.4 0.7 210 15 8 7.1 3.9 | -17.1 1.2 195 14 7 7.4 4.1
12500 -16.3 2.7 210 14 7 7.2 4.0 | -16.0 3.2 190 13 7 7.2 3.9
12000 -15.2 4.6 205 14 7 7.6 4.2 | -15.0 5.0 185 12 6 6.8 3.7
11500 -14.1 6.6 205 13 7 7.4 4.1 | -13.9 7.0 180 11 6 6.4 3.5
11000 -13.1 8.4 205 12 6 7.0 3.8 | -13.1 8.4 175 10 5 5.8 3.2
10500 -12.0 10.4 200 11 6 6.4 3.5 | -12.2 10.0 165 9 5 5.0 2.8
10250 -11.6 11.1 195 11 6 5.4 3.0 | -11.9 10.6 155 8 4 3.9 2.1
10000 -11.2 11.8 195 10 5 6.1 3.3 | -11.6 11.1 150 7 4 4.9 2.7
9750 -10.7 12.7 190 10 5 7.5 4.1 | -11.1 12.0 145 7 4 6.6 3.6
9500 -10.2 13.6 190 9 4 4.5 2.5 | -10.6 12.9 140 6 3 7.3 4.0
9250 -10.0 14.0 185 8 4 1.7 0.9 | -10.1 13.8 135 6 3 7.5 4.1
9000 -9.8 14.4 175 7 4 2.4 1.3 | -9.5 14.9 130 6 3 7.1 3.9
8750 -9.7 14.5 170 6 3 2.4 1.3 | -9.0 15.8 125 5 3 6.6 3.6
8500 -9.5 14.9 165 5 3 2.9 1.6 | -8.5 16.7 120 5 3 7.5 4.1
8250 -9.2 15.4 155 4 2 3.0 1.7 | -7.9 17.8 115 4 2 7.3 4.0
8000 -9.0 15.8 140 3 1 3.0 1.6 | -7.3 18.9 105 4 2 9.9 5.5
7750 -8.7 16.3 110 2 1 6.8 3.7 | -6.5 20.3 095 3 2 9.9 5.4
7500 -8.0 17.6 100 2 1 9.3 5.1 | -5.9 21.4 085 3 2 7.2 3.9
7250 -7.4 18.7 090 2 1 8.4 4.6 | -5.3 22.5 080 3 1 7.2 4.0
7000 -6.7 19.9 080 2 1 8.4 4.6 | -4.8 23.4 070 3 1 9.7 5.3
6750 -6.1 21.0 070 2 1 9.4 5.2 | -3.9 25.0 055 2 1 10.7 5.8
6500 -5.3 22.5 070 2 1 10.7 5.9 | -3.3 26.1 050 2 1 8.2 4.5
6250 -4.5 23.9 065 2 1 10.5 5.8 | -2.6 27.3 040 2 1 9.0 5.0
6000 -3.7 25.3 060 2 1 11.1 6.1 | -1.9 28.6 035 2 1 11.5 6.3
5750 -2.9 26.8 055 2 1 9.9 5.4 | -1.0 30.2 025 2 1 10.2 5.6
5500 -2.1 28.2 055 2 1 12.7 7.0 | -0.4 31.3 020 2 1 6.1 3.4
________________________________________________________________________________
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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