Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 010055
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1754 MST Thursday, November 30, 2023

This forecast is for Friday, December 1, 2023:

If the trigger temperature of 43.5 F/6.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8146 ft MSL (2840 ft AGL)

Forecast maximum temperature................... 39.0 F/4.3 C
Time of trigger temperature.................... None
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................. 7037 ft MSL (1730 ft AGL)
Thermal soaring outlook for Saturday 12/02..... Good

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....................... 16600 ft MSL (11294 ft AGL)
Wave soaring outlook for Saturday 12/02........ Fair

Remarks... Stronger west/northwest flow both surface and aloft by Saturday

Sunrise/Sunset.................... 07:01:33 / 16:35:29 MST
Total possible sunshine........... 9 hr 33 min 57 sec (573 min 57 sec)
Altitude of sun at 11:48:31 MST... 28.33 degrees

Upper air data from numerical model forecast valid on 12/01/2023 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 12362 ft MSL (7056 ft AGL)
Lifted condensation level....... 10194 ft MSL (4888 ft AGL)
Lifted index.................... +6.3
K index......................... +15.8

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  -55.0 -67.0   245   38   19   1.2   0.7      M     M       M      M    M
 45000  -53.2 -63.8   235   41   21   1.2   0.7      M     M       M      M    M
 40000  -52.5 -62.5   225   43   22   0.3   0.2      M     M       M      M    M
 38000  -52.3 -62.1   220   43   22  -1.6  -0.9      M     M       M      M    M
 36000  -53.6 -64.5   225   37   19  -2.1  -1.1      M     M       M      M    M
 34000  -54.9 -66.8   235   32   16  -2.1  -1.1      M     M       M      M    M
 32000  -53.7 -64.7   235   30   15   4.0   2.2      M     M       M      M    M
 30000  -51.3 -60.3   230   30   15   4.1   2.2      M     M       M      M    M
 29000  -49.7 -57.5   230   30   15   7.1   3.9   23.7  74.7    14.9      M    M
 28000  -47.1 -52.8   235   30   15   7.1   3.9   22.3  72.1    14.1      M    M
 27000  -45.0 -49.0   235   30   15   7.1   3.9   21.3  70.4    13.5      M    M
 26000  -42.9 -45.2   235   30   15   7.4   4.0   20.4  68.7    12.9      M    M
 25000  -40.7 -41.3   235   30   15   7.3   4.0   19.4  66.9    12.3      M    M
 24000  -38.5 -37.3   235   30   15   7.3   4.0   18.5  65.3    11.7      M    M
 23000  -36.2 -33.2   235   30   15   8.0   4.4   17.7  63.9    11.3      M    M
 22000  -33.8 -28.8   235   28   15   8.0   4.4   17.0  62.6    10.8      M    M
 21000  -31.5 -24.7   230   27   14   8.0   4.4   16.4  61.6    10.4      M    M
 20000  -29.1 -20.4   225   25   13   7.6   4.2   15.7  60.3    10.0      M    M
 19500  -28.0 -18.4   230   23   12   7.6   4.2   15.3  59.6     9.7      M    M
 19000  -26.9 -16.4   230   21   11   7.6   4.2   15.0  58.9     9.4      M    M
 18500  -25.7 -14.3   230   19   10   7.7   4.2   14.6  58.3     9.1      M    M
 18000  -24.6 -12.3   235   18    9   7.8   4.3   14.3  57.8     8.9      M    M
 17500  -23.4 -10.1   235   16    8   8.2   4.5   14.0  57.2     8.7      M    M
 17000  -22.2  -8.0   240   15    8   8.3   4.5   13.7  56.7     8.5      M    M
 16500  -21.1  -6.0   245   14    7   6.9   3.8   13.4  56.1     8.2      M    M
 16000  -20.0  -4.0   250   14    7   7.0   3.8   12.9  55.2     7.8      M    M
 15500  -19.0  -2.2   260   14    7   7.4   4.1   12.5  54.5     7.5      M    M
 15000  -17.3   0.9   265   14    7   7.6   4.2   11.9  53.5     7.0      M    M
 14500  -16.2   2.8   270   14    7   7.6   4.2   11.6  52.8     6.7      M    M
 14000  -15.1   4.8   275   14    7   7.6   4.2   11.2  52.2     6.4      M    M
 13500  -14.0   6.8   285   14    7   7.2   4.0   10.8  51.5     6.1      M    M
 13000  -12.9   8.8   290   14    7   7.2   4.0   10.4  50.7     5.7      M    M
 12500  -11.8  10.8   295   14    7   7.0   3.9   10.0  50.0     5.4      M    M
 12000  -10.8  12.6   300   13    7   7.0   3.8    9.6  49.2     5.0      M    M
 11500   -9.8  14.4   300   13    7   7.1   3.9    9.1  48.4     4.6      M    M
 11000   -8.7  16.3   305   13    7   7.1   3.9    8.7  47.6     4.2      M    M
 10500   -7.8  18.0   310   13    7   6.1   3.3    8.2  46.8     3.7      M    M
 10250   -7.3  18.9   310   13    7   5.6   3.0    7.9  46.2     3.4      M    M
 10000   -6.9  19.6   310   13    6   6.6   3.6    7.6  45.7     3.1      M    M
  9750   -6.4  20.5   315   12    6   6.6   3.6    7.4  45.3     2.9      M    M
  9500   -6.0  21.2   315   12    6   5.1   2.8    7.0  44.7     2.6      M    M
  9250   -5.6  21.9   315   12    6   5.1   2.8    6.7  44.0     2.3      M    M
  9000   -5.2  22.6   315   11    6   4.8   2.7    6.3  43.4     1.9      M    M
  8750   -4.9  23.2   315   11    6   2.7   1.5    5.9  42.6     1.5      M    M
  8500   -4.8  23.4   315   10    5   1.4   0.8    5.2  41.4     0.9      M    M
  8250   -4.7  23.5   315    9    5   1.8   1.0    4.6  40.3     0.3      M    M
  8000   -4.6  23.7   315    9    4   1.6   0.9    4.0  39.2    -0.3    207  1.0
  7750   -4.5  23.9   320    7    4   1.0   0.5    3.4  38.1    -1.0    196  1.0
  7500   -4.4  24.1   320    7    4   0.4   0.2    2.7  36.8    -1.7    187  1.0
  7250   -4.4  24.1   320    6    3   0.9   0.5    2.0  35.5    -2.3    179  0.9
  7000   -4.4  24.1   320    6    3  -0.8  -0.5    1.3  34.3    -3.0    170  0.9
  6750   -4.5  23.9   320    6    3  -2.6  -1.4    0.3  32.6    -3.9    167  0.8
  6500   -4.7  23.5   320    7    3  -2.5  -1.4   -0.6  31.0    -4.8    165  0.8
  6250   -4.8  23.4   315    7    4  -1.9  -1.0   -1.5  29.3    -5.7    163  0.8
  6000   -5.0  23.0   315    6    3  -1.9  -1.0   -2.4  27.8    -6.6    159  0.8
  5750   -5.1  22.8   310    5    3   1.1   0.6   -3.2  26.3    -7.5    155  0.8
  5500   -4.7  23.5   310    4    2   9.2   5.1   -3.5  25.7    -7.9    137  0.7

 * * * * * * Numerical weather prediction model forecast data valid * * * * * *

           12/01/2023 at 0800 MST          |       12/01/2023 at 1100 MST
                                           |
CAPE...     0.0    LI...       +2.4        | CAPE...     0.0    LI...       +1.8
CINH...     0.0    K Index... +13.4        | CINH...     0.0    K Index... +16.3
                                           |
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 -53.9 -65.0  240  39 20   1.3   0.7 | -53.7 -64.7  240  42 21   1.8   1.0
 45000 -51.9 -61.4  235  46 24   1.3   0.7 | -51.1 -60.0  235  46 24   1.8   1.0
 40000 -51.0 -59.8  245  44 23   0.5   0.3 | -51.8 -61.2  235  38 20  -1.0  -0.5
 38000 -50.7 -59.3  250  43 22  -1.8  -1.0 | -52.4 -62.3  235  34 18  -1.0  -0.5
 36000 -52.7 -62.9  240  33 17  -3.2  -1.8 | -52.9 -63.2  235  35 18  -0.9  -0.5
 34000 -54.6 -66.3  230  25 13  -3.3  -1.8 | -53.5 -64.3  235  37 19  -1.0  -0.5
 32000 -54.5 -66.1  225  24 12   2.3   1.3 | -53.4 -64.1  230  35 18   0.9   0.5
 30000 -53.1 -63.6  235  26 13   2.3   1.3 | -52.8 -63.0  225  31 16   0.9   0.5
 29000 -51.2 -60.2  240  28 14   7.7   4.2 | -51.5 -60.7  225  29 15   7.0   3.8
 28000 -48.9 -56.0  240  29 15   7.8   4.3 | -49.3 -56.7  225  28 15   7.2   3.9
 27000 -46.5 -51.7  245  30 15   7.8   4.3 | -47.2 -53.0  230  28 14   7.2   3.9
 26000 -44.2 -47.6  250  31 16   8.3   4.6 | -45.0 -49.0  235  28 14   8.2   4.5
 25000 -41.7 -43.1  250  31 16   8.3   4.5 | -42.5 -44.5  240  29 15   8.3   4.5
 24000 -39.2 -38.6  255  31 16   8.3   4.6 | -40.0 -40.0  245  30 16   8.3   4.5
 23000 -36.8 -34.2  255  31 16   7.7   4.3 | -37.6 -35.7  245  31 16   7.7   4.2
 22000 -34.5 -30.1  255  29 15   7.8   4.3 | -35.3 -31.5  245  31 16   7.7   4.2
 21000 -32.2 -26.0  255  27 14   7.8   4.3 | -33.0 -27.4  250  30 15   7.7   4.2
 20000 -29.9 -21.8  255  24 12   7.7   4.2 | -30.7 -23.3  250  28 14   7.9   4.3
 19500 -28.7 -19.7  255  22 12   7.7   4.2 | -29.5 -21.1  245  26 13   7.9   4.3
 19000 -27.6 -17.7  255  21 11   7.7   4.2 | -28.4 -19.1  240  24 12   7.9   4.3
 18500 -26.4 -15.5  255  19 10   7.7   4.2 | -27.2 -17.0  240  22 11   7.9   4.3
 18000 -25.3 -13.5  250  17  9   7.6   4.2 | -26.0 -14.8  235  20 10   7.8   4.3
 17500 -24.2 -11.6  250  17  9   7.5   4.1 | -24.9 -12.8  235  19 10   7.6   4.1
 17000 -23.0  -9.4  250  16  8   7.5   4.1 | -23.8 -10.8  235  18  9   7.5   4.1
 16500 -21.9  -7.4  255  15  8   7.4   4.1 | -22.6  -8.7  235  17  9   8.0   4.4
 16000 -20.8  -5.4  255  14  7   7.4   4.1 | -20.9  -5.6  235  16  8   8.0   4.4
 15500 -19.2  -2.6  260  14  7   7.6   4.2 | -19.7  -3.5  240  15  8   7.5   4.1
 15000 -18.1  -0.6  260  13  7   7.7   4.2 | -18.6  -1.5  240  15  8   7.6   4.2
 14500 -17.0   1.4  265  12  6   7.2   3.9 | -17.5   0.5  245  14  7   7.3   4.0
 14000 -15.9   3.4  270  12  6   7.2   3.9 | -16.4   2.5  250  14  7   7.3   4.0
 13500 -14.8   5.4  275  11  6   7.4   4.1 | -15.4   4.3  255  13  7   7.2   4.0
 13000 -13.7   7.3  280  10  5   7.5   4.1 | -14.3   6.3  260  13  7   7.2   4.0
 12500 -12.6   9.3  285  10  5   7.4   4.1 | -13.2   8.2  265  13  6   7.3   4.0
 12000 -11.5  11.3  290   9  5   7.5   4.1 | -12.1  10.2  270  12  6   7.3   4.0
 11500 -10.5  13.1  295   9  5   7.1   3.9 | -11.0  12.2  275  12  6   7.6   4.2
 11000  -9.4  15.1  300   9  4   7.0   3.8 |  -9.9  14.2  280  11  6   7.7   4.2
 10500  -8.4  16.9  305   8  4   7.0   3.8 |  -8.7  16.3  285  10  5   7.7   4.2
 10250  -7.9  17.8  310   8  4   6.8   3.7 |  -8.2  17.2  285  10  5   7.6   4.2
 10000  -7.4  18.7  310   8  4   7.5   4.1 |  -7.6  18.3  290   9  5   8.1   4.4
  9750  -6.8  19.8  315   8  4   7.5   4.1 |  -7.0  19.4  290   9  4   8.2   4.5
  9500  -6.3  20.7  320   8  4   6.3   3.5 |  -6.4  20.5  295   8  4   7.7   4.2
  9250  -5.8  21.6  320   8  4   6.7   3.7 |  -5.8  21.6  295   7  4   7.8   4.3
  9000  -5.3  22.5  320   8  4   5.3   2.9 |  -5.2  22.6  300   7  3   7.5   4.1
  8750  -5.0  23.0  325   8  4   3.8   2.1 |  -4.7  23.5  300   6  3   6.0   3.3
  8500  -4.7  23.5  325   8  4   4.3   2.3 |  -4.3  24.3  300   5  3   5.2   2.8
  8250  -4.4  24.1  320   7  4   3.9   2.2 |  -3.9  25.0  305   5  2   5.2   2.8
  8000  -4.1  24.6  320   7  4   4.8   2.6 |  -3.6  25.5  310   4  2   6.0   3.3
  7750  -3.8  25.2  320   7  3   2.9   1.6 |  -3.1  26.4  310   4  2   4.6   2.5
  7500  -3.7  25.3  320   6  3   0.6   0.3 |  -2.9  26.8  310   3  2   2.6   1.4
  7250  -3.6  25.5  325   5  3   1.3   0.7 |  -2.7  27.1  305   3  1   3.2   1.8
  7000  -3.6  25.5  325   4  2  -0.0  -0.0 |  -2.4  27.7  300   2  1   2.6   1.4
  6750  -3.6  25.5  325   4  2  -1.9  -1.0 |  -2.3  27.9  290   2  1   1.4   0.8
  6500  -3.8  25.2  320   3  2  -2.2  -1.2 |  -2.2  28.0  270   1  1   0.1   0.0
  6250  -4.0  24.8  310   3  2  -2.6  -1.4 |  -2.2  28.0  220   1  0   2.3   1.3
  6000  -4.2  24.4  300   3  1  -3.8  -2.1 |  -1.9  28.6  000   0  0   5.5   3.0
  5750  -4.5  23.9  280   2  1  -1.7  -0.9 |  -1.5  29.3  000   0  0   6.2   3.4
  5500  -4.4  24.1  265   2  1   5.6   3.1 |  -0.9  30.4  055   1  0  11.9   6.5

           12/01/2023 at 1400 MST          |       12/01/2023 at 1700 MST
                                           |
CAPE...     0.0    LI...       +1.4        | CAPE...     0.0    LI...       +0.5
CINH...     0.0    K Index... +19.1        | CINH...     0.0    K Index... +21.3
                                           |
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  240  44 23   0.8   0.4 | -53.2 -63.8  245  44 22   0.0   0.0
 45000 -52.3 -62.1  240  48 25   0.8   0.4 | -53.2 -63.8  250  46 24   0.0   0.0
 40000 -52.0 -61.6  245  48 25   0.0   0.0 | -52.9 -63.2  250  54 28   0.2   0.1
 38000 -52.0 -61.6  245  48 25  -0.1  -0.0 | -52.8 -63.0  250  57 29   0.1   0.1
 36000 -52.6 -62.7  245  49 25  -1.0  -0.5 | -52.9 -63.2  250  60 31  -0.2  -0.1
 34000 -53.2 -63.8  240  51 26  -1.0  -0.5 | -53.1 -63.6  250  62 32  -0.2  -0.1
 32000 -52.8 -63.0  240  47 24   1.6   0.9 | -51.8 -61.2  250  60 31   3.2   1.8
 30000 -51.8 -61.2  235  42 21   1.6   0.9 | -49.8 -57.6  245  57 30   3.2   1.8
 29000 -50.9 -59.6  235  39 20   5.4   3.0 | -48.9 -56.0  245  54 28   2.7   1.5
 28000 -49.3 -56.7  235  38 20   5.3   2.9 | -48.1 -54.6  240  48 25   2.7   1.5
 27000 -47.7 -53.9  235  37 19   5.3   2.9 | -47.3 -53.1  235  42 22   2.7   1.5
 26000 -46.0 -50.8  230  35 18   6.8   3.8 | -46.5 -51.7  230  36 19   5.1   2.8
 25000 -43.7 -46.7  235  33 17   7.8   4.3 | -44.4 -47.9  230  33 17   6.9   3.8
 24000 -41.4 -42.5  240  31 16   7.8   4.3 | -42.3 -44.1  230  30 16   6.9   3.8
 23000 -39.0 -38.2  245  30 15   8.3   4.5 | -40.2 -40.4  225  28 14   8.5   4.7
 22000 -36.5 -33.7  245  29 15   8.6   4.7 | -37.4 -35.3  230  27 14   9.6   5.2
 21000 -33.9 -29.0  250  28 14   8.6   4.7 | -34.5 -30.1  230  26 13   9.6   5.2
 20000 -31.4 -24.5  250  27 14   8.2   4.5 | -31.8 -25.2  235  25 13   8.2   4.5
 19500 -30.1 -22.2  250  26 13   8.3   4.5 | -30.5 -22.9  235  24 12   8.3   4.6
 19000 -28.3 -18.9  255  24 12   8.3   4.5 | -28.7 -19.7  240  24 12   8.3   4.6
 18500 -27.1 -16.8  255  23 12   8.3   4.5 | -27.4 -17.3  245  23 12   8.3   4.6
 18000 -25.8 -14.4  255  22 11   8.1   4.5 | -26.2 -15.2  250  23 12   8.0   4.4
 17500 -24.6 -12.3  260  20 10   8.1   4.4 | -25.0 -13.0  250  22 12   7.9   4.3
 17000 -23.4 -10.1  260  19 10   8.1   4.4 | -23.8 -10.8  255  22 11   7.9   4.3
 16500 -22.2  -8.0  260  18  9   8.0   4.4 | -22.7  -8.9  255  21 11   8.0   4.4
 16000 -21.1  -6.0  265  17  9   8.0   4.4 | -21.5  -6.7  260  20 10   8.0   4.4
 15500 -19.9  -3.8  265  16  8   7.6   4.2 | -20.3  -4.5  260  19 10   8.3   4.6
 15000 -18.8  -1.8  270  15  8   7.7   4.2 | -19.0  -2.2  265  18  9   8.4   4.6
 14500 -17.6   0.3  270  14  7   7.4   4.0 | -17.8  -0.0  265  17  9   7.7   4.2
 14000 -16.6   2.1  275  13  7   7.3   4.0 | -16.7   1.9  270  16  8   7.7   4.2
 13500 -15.5   4.1  280  13  6   7.3   4.0 | -15.6   3.9  275  16  8   7.8   4.3
 13000 -14.4   6.1  280  12  6   7.2   4.0 | -14.4   6.1  280  15  8   7.8   4.3
 12500 -13.3   8.1  285  11  6   7.5   4.1 | -13.3   8.1  280  14  7   7.4   4.1
 12000 -12.2  10.0  285  10  5   7.7   4.2 | -12.2  10.0  285  13  7   7.3   4.0
 11500 -11.1  12.0  285  10  5   7.6   4.2 | -11.1  12.0  285  12  6   7.2   4.0
 11000  -9.9  14.2  285   8  4   7.5   4.1 | -10.1  13.8  280  11  5   7.3   4.0
 10500  -8.8  16.2  280   7  4   7.6   4.2 |  -9.0  15.8  275   9  5   7.0   3.8
 10250  -8.3  17.1  280   7  4   7.8   4.3 |  -8.5  16.7  270   8  4   6.9   3.8
 10000  -7.7  18.1  280   6  3   7.4   4.1 |  -8.0  17.6  270   8  4   7.0   3.9
  9750  -7.1  19.2  280   6  3   7.6   4.2 |  -7.5  18.5  265   7  4   7.1   3.9
  9500  -6.5  20.3  280   5  3   8.3   4.5 |  -7.0  19.4  260   7  3   6.8   3.7
  9250  -5.9  21.4  285   4  2   8.8   4.8 |  -6.5  20.3  250   6  3   7.0   3.9
  9000  -5.3  22.5  290   3  2   7.3   4.0 |  -6.0  21.2  245   6  3   6.2   3.4
  8750  -4.8  23.4  300   3  1   6.8   3.7 |  -5.6  21.9  240   6  3   5.2   2.9
  8500  -4.2  24.4  305   2  1   8.0   4.4 |  -5.2  22.6  235   5  3   5.6   3.1
  8250  -3.6  25.5  320   2  1   7.4   4.0 |  -4.8  23.4  225   5  3   5.0   2.7
  8000  -3.0  26.6  350   1  1   8.9   4.9 |  -4.4  24.1  215   5  2   7.1   3.9
  7750  -2.4  27.7  030   1  1   6.5   3.6 |  -3.9  25.0  205   5  3   5.6   3.1
  7500  -2.1  28.2  055   1  1   3.3   1.8 |  -3.6  25.5  200   5  3   2.5   1.4
  7250  -1.8  28.8  075   1  1   4.0   2.2 |  -3.4  25.9  195   5  3   2.8   1.6
  7000  -1.5  29.3  090   2  1   4.2   2.3 |  -3.2  26.2  190   5  3   4.9   2.7
  6750  -1.2  29.8  080   2  1   5.4   3.0 |  -2.7  27.1  185   5  3   6.1   3.3
  6500  -0.8  30.6  070   2  1   5.4   3.0 |  -2.4  27.7  185   5  3   3.8   2.1
  6250  -0.4  31.3  060   3  1   7.0   3.8 |  -2.0  28.4  185   5  3   6.3   3.5
  6000   0.3  32.5  060   3  1  10.7   5.9 |  -1.4  29.5  185   5  3  10.5   5.8
  5750   1.2  34.2  055   3  1  11.0   6.1 |  -0.6  30.9  185   5  3   9.9   5.4
  5500   2.0  35.6  050   3  1  12.0   6.6 |   0.1  32.2  185   5  2   7.9   4.3
________________________________________________________________________________

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.

042613


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