741
UXUS97 KBOU 020118
SRGBOU
SOARING FORECAST
NATIONAL WEATHER SERVICE DENVER/BOULDER, COLORADO
1814 MST THURSDAY, DECEMBER 1, 2022
THIS FORECAST IS FOR FRIDAY, DECEMBER 2, 2022:
IF THE TRIGGER TEMPERATURE OF 62.2 F/16.8 C IS REACHED...THEN
THERMAL SOARING INDEX....................... POOR
MAXIMUM RATE OF LIFT........................ 0 FT/MIN (0.0 M/S)
MAXIMUM HEIGHT OF THERMALS.................. 6363 FT MSL (1055 FT AGL)
FORECAST MAXIMUM TEMPERATURE................... 52.0 F/11.6 C
TIME OF TRIGGER TEMPERATURE.................... NONE
TIME OF OVERDEVELOPMENT........................ NONE
MIDDLE/HIGH CLOUDS DURING SOARING WINDOW....... OVERCAST OPAQUE HIGH
SURFACE WINDS DURING SOARING WINDOW............ BETWEEN 20 MPH AND 30 MPH
HEIGHT OF THE -3 THERMAL INDEX................. 5531 FT MSL (223 FT AGL)
THERMAL SOARING OUTLOOK FOR SATURDAY 12/03..... 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)................ NEITHER
POTENTIAL HEIGHT OF WAVE....................... 17385 FT MSL (12077 FT AGL)
WAVE SOARING OUTLOOK FOR SATURDAY 12/03........ GOOD
REMARKS...
SUNRISE/SUNSET.................... 07:02:46 / 16:35:13 MST
TOTAL POSSIBLE SUNSHINE........... 9 HR 32 MIN 27 SEC (572 MIN 27 SEC)
ALTITUDE OF SUN AT 11:49:00 MST... 28.15 DEGREES
UPPER AIR DATA FROM NUMERICAL MODEL FORECAST VALID ON 12/02/2022 AT 0500 MST
FREEZING LEVEL.................. 12470 FT MSL (7162 FT AGL)
CONVECTIVE CONDENSATION LEVEL... 20241 FT MSL (14933 FT AGL)
LIFTED CONDENSATION LEVEL....... 13851 FT MSL (8543 FT AGL)
LIFTED INDEX.................... +11.1
K INDEX......................... +1.7
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 -66.8 -88.2 250 87 45 3.3 1.8 M M M M M
45000 -61.8 -79.2 250 92 47 3.4 1.8 M M M M M
40000 -60.2 -76.4 255 108 55 1.0 0.5 M M M M M
38000 -58.9 -74.0 255 106 55 4.0 2.2 M M M M M
36000 -56.5 -69.7 255 94 49 3.9 2.2 M M M M M
34000 -53.2 -63.8 255 82 42 9.1 5.0 M M M M M
32000 -47.8 -54.0 255 78 40 9.0 5.0 M M M M M
30000 -42.4 -44.3 255 74 38 8.5 4.7 32.8 91.1 16.4 M M
29000 -39.9 -39.8 255 71 37 8.5 4.7 32.2 90.0 16.1 M M
28000 -37.3 -35.1 255 69 35 8.6 4.7 31.8 89.2 16.0 M M
27000 -34.7 -30.5 250 66 34 8.5 4.7 31.5 88.7 15.9 M M
26000 -32.2 -26.0 250 65 33 8.5 4.7 30.9 87.6 15.6 M M
25000 -29.6 -21.3 250 63 33 8.5 4.7 30.4 86.8 15.4 M M
24000 -27.1 -16.8 250 62 32 8.5 4.7 30.1 86.1 15.3 M M
23000 -24.5 -12.1 250 59 30 8.7 4.8 29.6 85.3 15.1 M M
22000 -21.9 -7.4 250 56 29 8.7 4.8 29.2 84.5 14.9 M M
21000 -19.3 -2.7 250 52 27 8.5 4.7 28.9 84.0 14.8 M M
20000 -16.9 1.6 250 52 27 8.1 4.5 28.3 82.9 14.5 M M
19500 -15.6 3.9 250 52 27 8.1 4.5 28.0 82.3 14.3 M M
19000 -14.4 6.1 250 52 27 8.2 4.5 27.7 81.9 14.2 M M
18500 -13.2 8.2 250 52 27 8.3 4.5 27.5 81.4 14.0 M M
18000 -11.5 11.3 255 53 27 7.3 4.0 26.9 80.4 13.6 M M
17500 -10.4 13.3 255 53 28 7.3 4.0 26.5 79.7 13.3 M M
17000 -9.4 15.1 255 54 28 7.0 3.9 26.0 78.9 13.0 M M
16500 -8.3 17.1 255 53 28 7.1 3.9 25.6 78.0 12.7 M M
16000 -7.3 18.9 255 53 27 7.2 4.0 25.1 77.2 12.3 M M
15500 -6.2 20.8 255 53 27 7.3 4.0 24.7 76.5 12.0 M M
15000 -5.1 22.8 255 53 27 7.4 4.0 24.3 75.7 11.7 M M
14500 -4.0 24.8 255 52 27 7.6 4.1 23.9 75.1 11.4 M M
14000 -2.9 26.8 255 52 27 7.6 4.2 23.6 74.4 11.1 M M
13500 -1.9 28.6 255 53 27 6.4 3.5 23.1 73.6 10.7 M M
13000 -0.9 30.4 255 55 28 6.6 3.6 22.6 72.6 10.3 M M
12500 0.0 32.0 255 55 28 6.0 3.3 22.0 71.6 9.8 M M
12000 0.9 33.6 255 53 27 6.0 3.3 21.4 70.5 9.3 M M
11500 1.8 35.2 255 51 26 5.6 3.1 20.8 69.4 8.7 M M
11000 2.6 36.7 250 50 26 5.7 3.1 20.1 68.2 8.1 M M
10500 3.4 38.1 250 49 25 4.5 2.5 19.4 66.9 7.5 M M
10250 3.7 38.7 250 48 25 4.2 2.3 19.0 66.1 7.1 M M
10000 4.0 39.2 250 48 25 4.0 2.2 18.5 65.3 6.7 M M
9750 4.3 39.7 250 48 25 3.6 2.0 18.0 64.5 6.3 M M
9500 4.6 40.3 250 48 25 3.0 1.7 17.5 63.6 5.8 M M
9250 4.8 40.6 250 49 25 3.2 1.8 17.0 62.6 5.3 M M
9000 5.0 41.0 250 50 26 2.2 1.2 16.5 61.7 4.8 M M
8750 5.1 41.2 250 50 26 1.1 0.6 15.8 60.5 4.2 M M
8500 5.2 41.4 250 50 26 1.5 0.8 15.2 59.3 3.6 M M
8250 5.3 41.5 250 49 25 1.4 0.7 14.5 58.1 2.9 M M
8000 5.4 41.7 250 48 25 1.6 0.9 13.9 57.0 2.3 M M
7750 5.6 42.1 250 47 24 4.0 2.2 13.3 56.0 1.8 M M
7500 6.0 42.8 250 44 23 5.4 3.0 13.0 55.3 1.4 M M
7250 6.3 43.3 250 41 21 5.3 2.9 12.6 54.7 1.1 M M
7000 6.7 44.1 245 39 20 4.4 2.4 12.3 54.1 0.7 M M
6750 7.0 44.6 245 37 19 5.7 3.1 11.9 53.3 0.3 M M
6500 7.6 45.7 245 34 18 7.6 4.1 11.7 53.0 0.1 M M
6250 8.1 46.6 245 31 16 7.3 4.0 11.5 52.6 -0.1 87 0.4
6000 8.6 47.5 240 28 15 3.7 2.0 11.2 52.2 -0.3 66 0.3
5750 8.5 47.3 240 25 13 -7.1 -3.9 10.4 50.7 -1.2 61 0.3
5500 7.5 45.5 235 19 10 -15.9 -8.7 8.7 47.7 -2.8 82 0.4
* * * * * * NUMERICAL WEATHER PREDICTION MODEL FORECAST DATA VALID * * * * * *
12/02/2022 AT 0800 MST | 12/02/2022 AT 1100 MST
|
CAPE... 0.0 LI... +6.1 | CAPE... +5.0 LI... +5.0
CINH... -0.1 K INDEX... +1.3' | CINH... -3.5 K INDEX... +5.2'
|
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 -66.3 -87.3 250 84 43 3.7 2.0 | -65.4 -85.7 245 79 40 2.9 1.6
45000 -60.7 -77.3 250 86 44 3.8 2.1 | -61.1 -78.0 255 86 44 2.9 1.6
40000 -57.8 -72.0 255 99 51 1.9 1.0 | -55.9 -68.6 260 94 49 3.3 1.8
38000 -56.3 -69.3 255 102 52 3.7 2.0 | -53.8 -64.8 265 99 51 3.9 2.1
36000 -53.8 -64.8 255 100 51 3.7 2.0 | -51.4 -60.5 260 105 54 3.9 2.1
34000 -51.4 -60.5 255 98 50 7.0 3.8 | -49.1 -56.4 260 111 57 5.2 2.9
32000 -47.4 -53.3 255 94 49 6.6 3.6 | -45.6 -50.1 260 110 57 5.7 3.1
30000 -43.3 -45.9 250 90 47 8.3 4.5 | -42.2 -44.0 260 109 56 6.0 3.3
29000 -40.8 -41.4 250 88 45 8.1 4.5 | -40.4 -40.7 260 107 55 6.2 3.4
28000 -38.4 -37.1 250 85 44 8.1 4.5 | -38.1 -36.6 260 103 53 6.2 3.4
27000 -36.0 -32.8 250 83 43 8.1 4.5 | -36.2 -33.2 260 101 52 6.1 3.3
26000 -33.6 -28.5 250 81 42 7.9 4.3 | -34.1 -29.4 260 97 50 7.2 3.9
25000 -31.2 -24.2 250 80 41 7.9 4.3 | -32.0 -25.6 260 92 47 7.1 3.9
24000 -28.8 -19.8 250 79 41 7.9 4.3 | -29.9 -21.8 260 88 45 7.2 3.9
23000 -26.4 -15.5 250 75 39 8.3 4.5 | -27.8 -18.0 265 84 43 6.8 3.7
22000 -23.9 -11.0 245 69 36 8.3 4.5 | -25.8 -14.4 265 81 42 6.8 3.7
21000 -21.5 -6.7 245 63 33 8.3 4.6 | -23.7 -10.7 265 78 40 6.8 3.7
20000 -19.2 -2.6 245 61 31 7.5 4.1 | -21.8 -7.2 265 75 39 6.4 3.5
19500 -18.1 -0.6 245 60 31 7.5 4.1 | -20.8 -5.4 265 74 38 6.4 3.5
19000 -16.4 2.5 245 59 30 7.5 4.1 | -19.9 -3.8 265 72 37 6.4 3.5
18500 -15.3 4.5 245 59 30 7.4 4.0 | -18.9 -2.0 265 71 36 6.6 3.6
18000 -14.2 6.4 245 59 30 7.0 3.8 | -18.1 -0.6 260 69 36 4.4 2.4
17500 -13.2 8.2 250 59 30 7.0 3.9 | -17.5 0.5 260 69 35 4.4 2.4
17000 -12.1 10.2 250 59 30 6.8 3.7 | -16.8 1.8 260 68 35 4.5 2.4
16500 -11.1 12.0 250 59 31 6.8 3.7 | -16.2 2.8 260 67 34 4.5 2.5
16000 -10.1 13.8 255 60 31 6.6 3.6 | -15.5 4.1 260 66 34 4.5 2.5
15500 -9.1 15.6 255 60 31 6.3 3.5 | -14.8 5.4 265 65 33 4.9 2.7
15000 -8.2 17.2 255 60 31 6.3 3.4 | -13.8 7.2 265 64 33 5.6 3.1
14500 -7.3 18.9 255 59 30 6.0 3.3 | -12.7 9.1 265 62 32 7.4 4.1
14000 -6.4 20.5 260 57 30 6.0 3.3 | -11.7 10.9 265 60 31 7.4 4.1
13500 -5.5 22.1 260 57 29 6.6 3.6 | -10.5 13.1 265 56 29 8.8 4.8
13000 -4.5 23.9 260 57 30 6.6 3.6 | -9.2 15.4 265 51 26 8.8 4.8
12500 -3.6 25.5 260 58 30 5.6 3.1 | -8.0 17.6 265 48 25 7.7 4.2
12000 -2.8 27.0 260 60 31 5.6 3.1 | -6.8 19.8 265 47 24 7.8 4.3
11500 -2.0 28.4 265 62 32 5.0 2.8 | -5.7 21.7 265 46 24 7.5 4.1
11000 -1.2 29.8 260 63 33 5.0 2.8 | -4.6 23.7 265 45 23 7.6 4.2
10500 -0.6 30.9 260 64 33 3.9 2.1 | -3.6 25.5 270 44 22 6.3 3.4
10250 -0.3 31.5 260 65 33 3.8 2.1 | -3.1 26.4 270 43 22 6.9 3.8
10000 0.0 32.0 260 65 33 5.1 2.8 | -2.5 27.5 270 43 22 10.3 5.7
9750 0.4 32.7 260 64 33 5.5 3.0 | -1.6 29.1 270 43 22 9.9 5.4
9500 0.8 33.4 260 63 32 5.0 2.7 | -1.1 30.0 270 42 22 7.6 4.2
9250 1.2 34.2 260 61 32 5.1 2.8 | -0.5 31.1 270 41 21 7.9 4.4
9000 1.5 34.7 260 60 31 4.9 2.7 | 0.1 32.2 265 40 21 9.0 4.9
8750 1.9 35.4 255 58 30 5.5 3.0 | 0.9 33.6 265 40 21 9.7 5.3
8500 2.3 36.1 255 56 29 6.2 3.4 | 1.5 34.7 265 39 20 8.9 4.9
8250 2.8 37.0 255 54 28 6.2 3.4 | 2.2 36.0 265 37 19 9.3 5.1
8000 3.2 37.8 255 52 27 5.8 3.2 | 2.9 37.2 265 36 19 8.6 4.7
7750 3.7 38.7 250 50 26 5.9 3.2 | 3.5 38.3 265 34 18 9.0 4.9
7500 4.1 39.4 250 48 24 6.4 3.5 | 4.2 39.6 265 33 17 9.9 5.4
7250 4.6 40.3 250 45 23 6.3 3.5 | 4.9 40.8 265 32 17 9.7 5.3
7000 5.0 41.0 250 43 22 6.0 3.3 | 5.6 42.1 265 31 16 7.6 4.2
6750 5.5 41.9 245 41 21 6.3 3.5 | 6.2 43.2 260 30 16 8.8 4.8
6500 6.0 42.8 245 38 20 7.0 3.8 | 7.0 44.6 260 29 15 11.6 6.4
6250 6.5 43.7 245 35 18 6.4 3.5 | 7.8 46.0 260 27 14 10.0 5.5
6000 6.9 44.4 240 31 16 5.7 3.2 | 8.5 47.3 260 25 13 8.8 4.8
5750 7.2 45.0 240 27 14 0.3 0.2 | 9.1 48.4 260 23 12 8.9 4.9
5500 6.9 44.4 235 20 10 -8.4 -4.6 | 9.8 49.6 260 20 10 10.9 6.0
12/02/2022 AT 1400 MST | 12/02/2022 AT 1700 MST
|
CAPE... 0.0 LI... +5.3 | CAPE... 0.0 LI... +6.9
CINH... -0.0 K INDEX... -3.8' | CINH... -0.0 K INDEX... -24.2'
|
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 -64.0 -83.2 250 90 46 2.1 1.1 | -64.6 -84.3 255 95 49 2.0 1.1
45000 -60.9 -77.6 255 98 50 2.0 1.1 | -61.7 -79.1 260 104 53 1.9 1.1
40000 -56.6 -69.9 260 108 56 2.8 1.5 | -58.0 -72.4 265 117 60 2.4 1.3
38000 -54.7 -66.5 265 113 58 3.7 2.0 | -56.1 -69.0 265 122 63 4.2 2.3
36000 -52.4 -62.3 265 120 62 3.7 2.0 | -53.6 -64.5 265 126 65 4.2 2.3
34000 -50.1 -58.2 265 126 65 5.4 3.0 | -51.0 -59.8 265 130 67 5.8 3.2
32000 -46.6 -51.9 265 121 62 5.9 3.2 | -47.4 -53.3 265 123 63 6.0 3.3
30000 -43.1 -45.6 265 116 60 6.3 3.4 | -43.7 -46.7 265 115 59 6.8 3.7
29000 -41.2 -42.2 265 112 58 6.4 3.5 | -41.7 -43.1 265 111 57 6.8 3.8
28000 -39.3 -38.7 265 108 56 6.4 3.5 | -39.7 -39.5 265 107 55 6.8 3.8
27000 -37.4 -35.3 265 104 54 6.4 3.5 | -37.6 -35.7 265 103 53 6.8 3.7
26000 -34.8 -30.6 265 100 52 7.4 4.0 | -34.9 -30.8 270 99 51 7.5 4.1
25000 -32.6 -26.7 265 97 50 7.4 4.0 | -32.6 -26.7 270 96 49 7.5 4.1
24000 -30.4 -22.7 265 94 49 7.5 4.1 | -30.4 -22.7 270 93 48 7.8 4.3
23000 -28.5 -19.3 265 90 47 5.7 3.1 | -28.6 -19.5 270 89 46 5.5 3.0
22000 -26.8 -16.2 265 86 44 5.7 3.1 | -27.0 -16.6 270 84 43 5.5 3.0
21000 -25.1 -13.2 265 82 42 5.8 3.2 | -25.3 -13.5 275 79 40 5.5 3.0
20000 -23.2 -9.8 265 76 39 6.4 3.5 | -23.7 -10.7 275 75 38 5.6 3.0
19500 -22.2 -8.0 265 73 38 6.4 3.5 | -22.8 -9.0 275 73 38 5.6 3.0
19000 -21.3 -6.3 260 70 36 6.4 3.5 | -22.0 -7.6 275 71 37 5.6 3.1
18500 -20.3 -4.5 260 67 34 6.4 3.5 | -21.2 -6.2 275 69 36 5.7 3.1
18000 -19.3 -2.7 260 62 32 7.3 4.0 | -20.2 -4.4 275 67 35 6.9 3.8
17500 -18.2 -0.8 260 57 29 7.2 3.9 | -19.2 -2.6 275 64 33 6.8 3.7
17000 -17.2 1.0 260 52 27 6.5 3.6 | -18.1 -0.6 280 62 32 7.8 4.3
16500 -16.2 2.8 260 51 26 6.1 3.4 | -16.9 1.6 280 61 31 7.9 4.4
16000 -15.3 4.5 260 50 26 5.9 3.2 | -15.7 3.7 280 60 31 7.7 4.2
15500 -14.6 5.7 260 51 26 5.0 2.7 | -14.6 5.7 275 55 28 7.4 4.1
15000 -13.8 7.2 260 52 27 5.1 2.8 | -13.5 7.7 275 50 26 7.2 3.9
14500 -13.2 8.2 260 53 27 4.1 2.2 | -12.6 9.3 275 47 24 4.7 2.6
14000 -12.6 9.3 260 52 27 4.1 2.2 | -11.9 10.6 275 46 23 5.0 2.8
13500 -11.9 10.6 260 51 26 5.6 3.1 | -11.3 11.7 270 43 22 3.9 2.1
13000 -11.1 12.0 260 48 25 5.6 3.1 | -10.7 12.7 270 41 21 4.0 2.2
12500 -10.1 13.8 260 46 24 8.0 4.4 | -9.8 14.4 265 38 20 4.5 2.5
12000 -8.9 16.0 260 43 22 8.4 4.6 | -9.1 15.6 260 37 19 5.1 2.8
11500 -7.1 19.2 260 39 20 7.9 4.3 | -8.2 17.2 260 36 19 6.1 3.4
11000 -5.9 21.4 260 35 18 7.5 4.1 | -7.4 18.7 260 36 18 6.1 3.4
10500 -5.0 23.0 265 33 17 6.2 3.4 | -6.5 20.3 260 34 18 6.2 3.4
10250 -4.5 23.9 265 32 16 5.7 3.1 | -6.0 21.2 260 33 17 5.9 3.3
10000 -4.0 24.8 270 30 16 11.3 6.2 | -5.7 21.7 260 33 17 2.8 1.5
9750 -3.0 26.6 270 29 15 11.4 6.3 | -5.5 22.1 260 32 16 4.8 2.6
9500 -2.4 27.7 275 28 14 6.8 3.7 | -4.9 23.2 265 30 16 8.7 4.8
9250 -1.8 28.8 280 27 14 8.4 4.6 | -4.3 24.3 265 29 15 6.8 3.7
9000 -1.3 29.7 280 26 14 5.2 2.8 | -3.9 25.0 265 28 14 4.0 2.2
8750 -0.9 30.4 280 26 13 6.8 3.7 | -3.7 25.3 270 26 14 5.4 2.9
8500 -0.2 31.6 285 26 13 10.6 5.8 | -3.1 26.4 275 25 13 8.2 4.5
8250 0.5 32.9 290 25 13 8.7 4.8 | -2.6 27.3 275 24 12 6.1 3.3
8000 1.1 34.0 290 25 13 6.2 3.4 | -2.2 28.0 280 22 12 3.5 1.9
7750 1.6 34.9 295 25 13 8.2 4.5 | -1.9 28.6 285 21 11 6.3 3.5
7500 2.3 36.1 295 25 13 11.6 6.4 | -1.3 29.7 290 20 10 8.4 4.6
7250 3.1 37.6 300 24 13 8.7 4.8 | -0.8 30.6 295 20 10 5.8 3.2
7000 3.6 38.5 300 24 13 5.6 3.1 | -0.4 31.3 300 19 10 4.2 2.3
6750 4.1 39.4 305 24 12 9.5 5.2 | -0.0 32.0 305 19 10 6.4 3.5
6500 5.0 41.0 305 24 12 11.6 6.4 | 0.5 32.9 315 18 10 6.5 3.6
6250 5.7 42.3 310 23 12 8.5 4.7 | 0.9 33.6 320 18 9 4.7 2.6
6000 6.3 43.3 310 23 12 6.7 3.7 | 1.2 34.2 325 17 9 5.0 2.7
5750 6.9 44.4 310 22 11 10.7 5.9 | 1.6 34.9 330 16 8 5.1 2.8
5500 8.0 46.4 315 19 10 17.6 9.7 | 2.0 35.6 335 13 7 4.1 2.3
________________________________________________________________________________
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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