Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 151208
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0608 MDT Friday, March 15, 2024

This forecast is for the Air Force Academy for Friday, March 15, 2024:

If the trigger temperature of 34.7 F/1.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 11638 ft MSL (4044 ft AGL)

Forecast maximum temperature................... 35.0 F/2.1 C
Time of trigger temperature.................... 1400 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10314 ft MSL (2720 ft AGL)
Thermal soaring outlook for Saturday 03/16..... Poor

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 07:09:12 / 19:06:41 MDT
Total possible sunshine........... 11 hr 57 min 28 sec (717 min 28 sec)
Altitude of sun at 13:07:57 MDT... 49.26 degrees

Upper air data from numerical model forecast valid on 03/15/2024 at 0600 MDT

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 10630 ft MSL (3036 ft AGL)
Lifted condensation level....... 11708 ft MSL (4114 ft AGL)
Lifted index.................... +6.5
K index......................... +10.6

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  -54.9 -66.8   250   19   10   1.7   0.9      M     M       M      M    M
 45000  -52.4 -62.3   255   24   12   1.8   1.0      M     M       M      M    M
 40000  -56.0 -68.8   220   35   18  -2.6  -1.4      M     M       M      M    M
 38000  -56.9 -70.4   220   38   19   0.2   0.1      M     M       M      M    M
 36000  -56.8 -70.2   235   37   19   0.2   0.1      M     M       M      M    M
 34000  -56.6 -69.9   245   39   20   3.3   1.8      M     M       M      M    M
 32000  -53.6 -64.5   240   42   21   5.0   2.7      M     M       M      M    M
 30000  -50.4 -58.7   240   44   23   8.6   4.7   18.0  64.4    12.5      M    M
 29000  -47.8 -54.0   240   43   22   8.6   4.7   17.4  63.3    12.2      M    M
 28000  -45.2 -49.4   235   41   21   8.7   4.7   17.0  62.6    12.0      M    M
 27000  -42.6 -44.7   235   40   21   8.6   4.7   16.7  62.1    11.9      M    M
 26000  -39.8 -39.6   235   39   20   9.8   5.4   16.6  61.8    12.0      M    M
 25000  -36.8 -34.2   235   39   20   9.8   5.4   16.6  61.8    12.1      M    M
 24000  -33.9 -29.0   230   39   20   9.9   5.4   16.7  62.0    12.3      M    M
 23000  -30.5 -22.9   230   38   19   9.0   5.0   16.4  61.4    12.2      M    M
 22000  -27.8 -18.0   230   36   19   9.1   5.0   16.1  61.0    12.2      M    M
 21000  -25.2 -13.4   225   35   18   7.3   4.0   15.8  60.5    12.0      M    M
 20000  -23.0  -9.4   220   34   17   7.2   3.9   14.9  58.7    11.3      M    M
 19500  -22.0  -7.6   220   33   17   7.2   3.9   14.4  58.0    11.0      M    M
 19000  -20.9  -5.6   220   32   17   7.2   3.9   14.0  57.2    10.7      M    M
 18500  -19.8  -3.6   220   31   16   7.5   4.1   13.6  56.5    10.4      M    M
 18000  -18.7  -1.7   215   30   15   7.5   4.1   13.2  55.8    10.1      M    M
 17500  -17.6   0.3   210   29   15   6.8   3.7   12.9  55.2     9.8      M    M
 17000  -16.9   1.6   200   26   13   3.9   2.2   12.1  53.7     9.1      M    M
 16500  -16.3   2.7   195   22   12   4.1   2.3   11.1  52.0     8.3      M    M
 16000  -15.7   3.7   185   20   10   3.8   2.1   10.2  50.3     7.5      M    M
 15500  -15.1   4.8   175   18    9   3.8   2.1    9.2  48.5     6.6      M    M
 15000  -14.5   5.9   165   17    9   5.5   3.0    8.3  46.9     5.8      M    M
 14500  -13.6   7.5   160   17    9   5.9   3.2    7.7  45.8     5.2      M    M
 14000  -12.7   9.1   150   17    9   5.9   3.2    7.1  44.7     4.7      M    M
 13500  -11.8  10.8   140   15    8   5.8   3.2    6.4  43.6     4.2      M    M
 13000  -10.9  12.4   125   14    7   4.5   2.5    5.8  42.5     3.7      M    M
 12500  -10.4  13.3   125    8    4   2.1   1.2    4.8  40.6     2.7      M    M
 12000  -10.4  13.3   150    5    3  -0.2  -0.1    3.3  38.0     1.3      M    M
 11750  -10.4  13.3   165    6    3  -0.9  -0.5    2.5  36.5     0.5      M    M
 11500  -10.5  13.1   180    6    3  -0.4  -0.2    1.7  35.0    -0.3    347  1.8
 11250  -10.6  12.9   190    8    4  -1.9  -1.0    0.9  33.5    -1.1    342  1.7
 11000  -10.7  12.7   190    8    4   2.1   1.1   -0.0  32.0    -2.0    338  1.7
 10750  -10.3  13.5   180    9    5   6.3   3.5   -0.3  31.4    -2.3    318  1.6
 10500   -9.9  14.2   175   10    5   5.2   2.8   -0.7  30.8    -2.7    299  1.5
 10250   -9.5  14.9   170   11    6   5.6   3.1   -1.0  30.2    -3.0    280  1.4
 10000   -9.1  15.6   165   12    6   5.3   2.9   -1.3  29.6    -3.4    260  1.3
  9750   -8.7  16.3   155   11    6   5.0   2.7   -1.7  28.9    -3.7    242  1.2
  9500   -8.4  16.9   140   11    6   5.3   2.9   -2.1  28.3    -4.1    223  1.1
  9250   -8.0  17.6   130   12    6   4.5   2.4   -2.4  27.6    -4.5    204  1.0
  9000   -7.6  18.3   125   12    6   7.3   4.0   -2.8  27.0    -4.8    186  0.9
  8750   -6.9  19.6   115   12    6  10.1   5.6   -2.8  27.0    -4.9    158  0.8
  8500   -6.2  20.8   110   12    6   9.4   5.2   -2.8  26.9    -4.9    130  0.7
  8250   -5.6  21.9   105   12    6   9.0   4.9   -2.8  26.9    -5.0    102  0.5
  8000   -4.9  23.2   105   11    6   9.0   4.9   -2.9  26.8    -5.1     75  0.4
  7750   -4.2  24.4   100    9    5  10.4   5.7   -2.9  26.8    -5.2     47  0.2
  7500      M     M     M    M    M     M     M      M     M       M      M    M
  7250      M     M     M    M    M     M     M      M     M       M      M    M
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           03/15/2024 at 0900 MDT          |       03/15/2024 at 1200 MDT
                                           |
CAPE...   +11.2    LI...       +3.3        | CAPE...    +9.4    LI...       +1.3
CINH...     0.0    K Index... +11.6        | CINH...     0.0    K Index... +15.1
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -56.3 -69.3  250  18  9   2.0   1.1 | -56.5 -69.7  255  27 14   1.7   0.9
 45000 -53.2 -63.8  260  15  8   1.2   0.7 | -53.8 -64.8  250  26 13   0.8   0.5
 40000 -56.2 -69.2  235  28 15  -2.1  -1.1 | -57.4 -71.3  230  35 18  -2.5  -1.4
 38000 -56.8 -70.2  230  33 17   0.7   0.4 | -58.0 -72.4  225  38 20   1.5   0.8
 36000 -56.4 -69.5  235  35 18   0.7   0.4 | -57.2 -71.0  225  39 20   1.5   0.8
 34000 -56.0 -68.8  235  38 19   2.7   1.5 | -55.8 -68.4  220  40 21   6.1   3.4
 32000 -53.0 -63.4  235  41 21   4.5   2.5 | -52.3 -62.1  210  37 19   5.8   3.2
 30000 -49.8 -57.6  230  42 22   9.5   5.2 | -48.5 -55.3  205  35 18   9.1   5.0
 29000 -47.0 -52.6  230  41 21   9.3   5.1 | -45.8 -50.4  210  33 17   9.0   5.0
 28000 -44.3 -47.7  230  40 21   9.3   5.1 | -43.1 -45.6  215  31 16   9.0   5.0
 27000 -41.5 -42.7  230  39 20   9.3   5.1 | -40.4 -40.7  220  29 15   8.9   4.9
 26000 -38.7 -37.7  230  37 19   9.3   5.1 | -37.7 -35.9  220  28 15   8.7   4.8
 25000 -36.0 -32.8  230  34 18   9.3   5.1 | -35.1 -31.2  225  28 14   8.8   4.8
 24000 -33.2 -27.8  235  32 16   9.2   5.1 | -32.5 -26.5  230  27 14   8.7   4.8
 23000 -30.5 -22.9  235  31 16   8.8   4.8 | -30.0 -22.0  230  26 13   8.6   4.7
 22000 -27.9 -18.2  235  30 15   8.8   4.8 | -27.4 -17.3  225  25 13   8.6   4.7
 21000 -25.3 -13.5  240  29 15   8.2   4.5 | -24.9 -12.8  225  23 12   7.9   4.4
 20000 -23.0  -9.4  245  30 16   7.9   4.3 | -22.1  -7.8  220  22 11   7.6   4.2
 19500 -21.8  -7.2  245  31 16   7.9   4.3 | -20.9  -5.6  220  21 11   7.6   4.2
 19000 -20.1  -4.2  250  32 16   7.9   4.3 | -19.8  -3.6  215  21 11   7.6   4.2
 18500 -18.9  -2.0  250  33 17   8.2   4.5 | -18.7  -1.7  215  21 11   7.7   4.2
 18000 -17.7   0.1  250  34 17   8.2   4.5 | -17.6   0.3  210  21 11   7.7   4.2
 17500 -16.5   2.3  250  35 18   7.7   4.2 | -16.4   2.5  210  22 11   7.5   4.1
 17000 -15.4   4.3  245  34 17   7.2   3.9 | -15.4   4.3  210  22 11   7.3   4.0
 16500 -14.4   6.1  240  33 17   7.1   3.9 | -14.3   6.3  210  22 11   7.3   4.0
 16000 -13.4   7.9  235  32 16   5.9   3.2 | -13.2   8.2  215  22 11   7.5   4.1
 15500 -12.5   9.5  230  30 15   6.3   3.4 | -12.1  10.2  215  22 11   7.5   4.1
 15000 -11.9  10.6  225  27 14   2.7   1.5 | -11.0  12.2  220  21 11   7.6   4.2
 14500 -11.5  11.3  220  24 12   2.7   1.5 |  -9.9  14.2  220  21 11   7.8   4.3
 14000 -11.1  12.0  210  21 11   1.4   0.8 |  -8.9  16.0  220  20 10   3.2   1.8
 13500 -11.0  12.2  200  18  9   1.0   0.5 |  -8.7  16.3  215  18  9   2.0   1.1
 13000 -10.8  12.6  180  16  8   1.3   0.7 |  -8.4  16.9  205  16  8  -0.3  -0.2
 12500 -10.6  12.9  160  15  8   1.5   0.8 |  -8.7  16.3  190  15  8  -0.9  -0.5
 12000 -10.4  13.3  150  15  8   3.1   1.7 |  -8.7  16.3  180  15  8   1.3   0.7
 11750 -10.1  13.8  150  14  7   4.4   2.4 |  -8.5  16.7  175  15  8   3.0   1.6
 11500  -9.8  14.4  145  13  7   4.0   2.2 |  -8.3  17.1  170  15  8   2.5   1.4
 11250  -9.5  14.9  140  12  6   4.5   2.5 |  -8.1  17.4  160  15  8   0.7   0.4
 11000  -9.2  15.4  140  12  6   2.2   1.2 |  -8.1  17.4  160  15  8   0.7   0.4
 10750  -9.1  15.6  145  12  6   0.3   0.2 |  -8.0  17.6  160  15  8   2.3   1.3
 10500  -9.1  15.6  150  13  6   0.5   0.3 |  -7.9  17.8  165  15  8   1.3   0.7
 10250  -9.0  15.8  155  13  7   1.6   0.9 |  -7.7  18.1  165  15  8   3.7   2.1
 10000  -8.8  16.2  160  13  7   2.6   1.4 |  -7.4  18.7  170  15  8   3.7   2.0
  9750  -8.7  16.3  165  14  7   2.0   1.1 |  -7.3  18.9  175  16  8   1.4   0.7
  9500  -8.6  16.5  170  15  8   2.0   1.1 |  -7.1  19.2  175  17  9   1.9   1.0
  9250  -8.4  16.9  170  16  8   2.6   1.4 |  -7.0  19.4  180  17  9   2.1   1.2
  9000  -8.1  17.4  170  15  8   6.0   3.3 |  -6.7  19.9  180  17  9   6.5   3.6
  8750  -7.6  18.3  170  15  8   7.8   4.3 |  -6.1  21.0  180  16  8   9.2   5.1
  8500  -7.0  19.4  170  14  7   7.5   4.1 |  -5.5  22.1  180  16  8   8.7   4.8
  8250  -6.5  20.3  170  13  7   7.8   4.3 |  -4.9  23.2  180  15  8   8.2   4.5
  8000  -5.8  21.6  165  12  6  10.7   5.9 |  -4.2  24.4  180  14  7  12.6   6.9
  7750  -4.8  23.4  165  10  5  16.0   8.8 |  -2.9  26.8  175  12  6  22.0  12.1
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           03/15/2024 at 1500 MDT          |       03/15/2024 at 1800 MDT
                                           |
CAPE...   +10.4    LI...       +1.2        | CAPE...    +1.0    LI...       +1.3
CINH...     0.0    K Index... +17.9        | CINH...     0.0    K Index... +19.6
                                           |
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 -56.4 -69.5  260  28 15   1.7   1.0 | -56.8 -70.2  255  32 16   1.9   1.0
 45000 -53.7 -64.7  255  34 18   0.8   0.4 | -53.8 -64.8  250  33 17   0.9   0.5
 40000 -57.0 -70.6  240  40 20  -2.3  -1.3 | -56.5 -69.7  250  34 18  -1.8  -1.0
 38000 -57.6 -71.7  235  42 21   1.1   0.6 | -56.8 -70.2  240  35 18   1.5   0.8
 36000 -56.9 -70.4  225  43 22   1.1   0.6 | -55.9 -68.6  225  37 19   1.5   0.8
 34000 -55.6 -68.1  215  45 23   6.7   3.7 | -54.4 -65.9  210  41 21   6.3   3.5
 32000 -51.8 -61.2  205  41 21   6.3   3.5 | -50.8 -59.4  210  37 19   6.0   3.3
 30000 -47.7 -53.9  200  39 20   9.0   4.9 | -47.1 -52.8  210  33 17   7.7   4.2
 29000 -45.0 -49.0  200  36 19   9.0   4.9 | -44.8 -48.6  210  31 16   7.7   4.2
 28000 -42.3 -44.1  200  34 18   9.0   4.9 | -42.5 -44.5  205  30 15   7.7   4.2
 27000 -39.6 -39.3  205  32 16   8.8   4.8 | -40.2 -40.4  200  29 15   7.9   4.4
 26000 -37.1 -34.8  205  29 15   8.6   4.7 | -37.7 -35.9  205  26 13   8.4   4.6
 25000 -34.5 -30.1  210  27 14   8.6   4.7 | -35.2 -31.4  205  22 12   8.4   4.6
 24000 -31.9 -25.4  210  24 12   8.5   4.7 | -32.7 -26.9  210  19 10   8.5   4.6
 23000 -29.5 -21.1  215  22 11   8.2   4.5 | -30.1 -22.2  215  16  8   8.7   4.8
 22000 -27.1 -16.8  220  19 10   8.2   4.5 | -27.5 -17.5  220  13  7   8.7   4.8
 21000 -24.6 -12.3  230  17  9   7.9   4.4 | -24.9 -12.8  225  10  5   8.2   4.5
 20000 -21.8  -7.2  235  14  7   7.8   4.3 | -22.0  -7.6  220   7  3   7.9   4.3
 19500 -20.6  -5.1  235  13  7   7.8   4.3 | -20.9  -5.6  215   5  3   7.9   4.3
 19000 -19.4  -2.9  240  12  6   7.9   4.3 | -19.7  -3.5  205   4  2   7.9   4.4
 18500 -18.3  -0.9  245  12  6   7.3   4.0 | -18.6  -1.5  200   4  2   7.5   4.1
 18000 -17.2   1.0  245  13  7   7.3   4.0 | -17.5   0.5  210   4  2   7.5   4.1
 17500 -16.2   2.8  245  14  7   7.4   4.0 | -16.4   2.5  220   4  2   7.2   4.0
 17000 -15.1   4.8  240  15  8   7.4   4.1 | -15.3   4.5  215   4  2   6.9   3.8
 16500 -14.0   6.8  240  16  8   7.4   4.1 | -14.3   6.3  210   4  2   6.9   3.8
 16000 -12.9   8.8  240  17  9   7.2   4.0 | -13.3   8.1  220   6  3   6.9   3.8
 15500 -11.9  10.6  235  19 10   7.2   4.0 | -12.3   9.9  230   8  4   6.9   3.8
 15000 -10.8  12.6  235  20 10   7.4   4.0 | -11.3  11.7  235  10  5   6.8   3.7
 14500  -9.7  14.5  235  21 11   7.4   4.1 | -10.3  13.5  240  12  6   6.8   3.7
 14000  -8.7  16.3  230  21 11   5.8   3.2 |  -9.3  15.3  245  13  7   7.4   4.1
 13500  -7.9  17.8  230  19 10   5.4   3.3 |  -8.1  17.4  240  15  8   7.6   4.2
 13000  -7.1  19.2  230  16  8   4.5   2.5 |  -7.0  19.4  240  16  8   7.4   4.1
 12500  -6.5  20.3  220  16  8   4.5   2.5 |  -6.0  21.2  235  17  9   6.3   3.5
 12000  -5.8  21.6  215  15  8   2.7   1.5 |  -5.1  22.8  235  16  8   4.8   2.7
 11750  -5.7  21.7  210  15  8   0.5   0.3 |  -4.8  23.4  230  16  8   3.3   1.8
 11500  -5.7  21.7  205  15  8   0.9   0.5 |  -4.5  23.9  230  16  8   3.8   2.1
 11250  -5.7  21.7  205  16  8  -0.9  -0.5 |  -4.2  24.4  225  16  8   5.2   2.8
 11000  -5.8  21.6  200  16  8  -1.6  -0.9 |  -3.9  25.0  220  16  8   3.2   1.7
 10750  -5.9  21.4  200  17  9  -1.2  -0.6 |  -3.8  25.2  220  16  8   0.8   0.4
 10500  -6.0  21.2  195  18  9  -1.7  -0.9 |  -3.7  25.3  215  16  8   1.4   0.8
 10250  -6.1  21.0  195  19 10  -0.1  -0.0 |  -3.6  25.5  210  17  9   1.3   0.7
 10000  -6.0  21.2  195  21 11   2.2   1.2 |  -3.5  25.7  210  17  9   1.2   0.6
  9750  -5.8  21.6  190  22 11   2.1   1.2 |  -3.4  25.9  205  18  9   0.9   0.5
  9500  -5.7  21.7  190  23 12   2.5   1.4 |  -3.3  26.1  205  18  9   1.2   0.7
  9250  -5.5  22.1  190  24 12   1.1   0.6 |  -3.3  26.1  205  19 10   0.3   0.1
  9000  -5.4  22.3  190  24 12   4.2   2.3 |  -3.3  26.1  200  19 10   1.2   0.7
  8750  -4.9  23.2  190  24 12   8.0   4.4 |  -3.1  26.4  200  19 10   2.9   1.6
  8500  -4.4  24.1  185  24 12   7.0   3.9 |  -3.0  26.6  195  20 10   2.2   1.2
  8250  -3.9  25.0  185  24 12   7.5   4.1 |  -2.8  27.0  195  20 10   3.4   1.9
  8000  -3.2  26.2  185  23 12  12.2   6.7 |  -2.4  27.7  190  19 10   8.1   4.5
  7750  -2.0  28.4  180  19 10  19.6  10.7 |  -1.7  28.9  185  15  8  13.0   7.1
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 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 Air Force Academy
in Colorado Springs, Colorado at

                   North Latitude:  38 deg 58 min 48.000 sec
                   West Longitude: 104 deg 49 min 12.000 sec
                   Elevation: 6572 feet (2003 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.

CIN (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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