Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 191219
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0618 MDT Friday, April 19, 2024

This forecast is for the Air Force Academy for Friday, April 19, 2024:

If the trigger temperature of 56.8 F/13.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 10528 ft MSL (2936 ft AGL)

Forecast maximum temperature................... 53.0 F/12.1 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 1600 MDT
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................. 9845 ft MSL (2253 ft AGL)
Thermal soaring outlook for Saturday 04/20..... Poor

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

Remarks...

Sunrise/Sunset.................... 06:15:44 / 19:40:44 MDT
Total possible sunshine........... 13 hr 25 min 0 sec (805 min 0 sec)
Altitude of sun at 12:58:14 MDT... 62.56 degrees

Upper air data from numerical model forecast valid on 04/19/2024 at 0600 MDT

Freezing level.................. 9421 ft MSL (1829 ft AGL)
Additional freezing level....... 12309 ft MSL (4717 ft AGL)
Convective condensation level... 16726 ft MSL (9134 ft AGL)
Lifted condensation level....... 14826 ft MSL (7235 ft AGL)
Lifted index.................... +5.1
K index......................... +12.1

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  -59.8 -75.6   265   58   30   2.1   1.2      M     M       M      M    M
 45000  -56.9 -70.4   260   62   32  -1.5  -0.8      M     M       M      M    M
 40000  -58.5 -73.3   260   74   38  -1.2  -0.6      M     M       M      M    M
 38000  -56.7 -70.1   260   74   38   5.7   3.1      M     M       M      M    M
 36000  -52.8 -63.0   260   72   37   5.7   3.1      M     M       M      M    M
 34000  -49.2 -56.6   260   66   34   6.5   3.6      M     M       M      M    M
 32000  -45.3 -49.5   260   55   28   6.5   3.6      M     M       M      M    M
 30000  -41.0 -41.8   265   47   24   8.5   4.7   27.7  81.9    12.4      M    M
 29000  -38.4 -37.1   265   47   24   8.5   4.7   27.2  80.9    12.1      M    M
 28000  -35.9 -32.6   265   47   24   8.5   4.7   26.8  80.2    11.9      M    M
 27000  -33.4 -28.1   265   47   24   8.1   4.4   26.4  79.5    11.7      M    M
 26000  -31.0 -23.8   265   47   24   8.0   4.4   25.6  78.2    11.3      M    M
 25000  -28.6 -19.5   260   47   24   8.1   4.4   25.0  77.1    10.9      M    M
 24000  -26.2 -15.2   260   46   24   6.8   3.7   24.5  76.1    10.6      M    M
 23000  -24.5 -12.1   265   47   24   5.7   3.1   22.9  73.3     9.4      M    M
 22000  -22.8  -9.0   265   47   24   5.7   3.1   21.5  70.7     8.3      M    M
 21000  -20.4  -4.7   265   46   24   7.8   4.3   20.1  68.1     7.1      M    M
 20000  -18.1  -0.6   260   44   22   7.8   4.3   19.3  66.8     6.5      M    M
 19500  -17.0   1.4   255   42   22   7.8   4.3   19.0  66.2     6.3      M    M
 19000  -15.8   3.6   255   41   21   7.8   4.3   18.7  65.7     6.0      M    M
 18500  -14.7   5.5   255   41   21   6.9   3.8   18.3  65.0     5.7      M    M
 18000  -13.7   7.3   255   41   21   7.0   3.8   17.9  64.1     5.3      M    M
 17500  -12.6   9.3   260   42   22   7.7   4.2   17.4  63.4     5.0      M    M
 17000  -11.3  11.7   260   45   23   8.1   4.5   17.1  62.9     4.8      M    M
 16500  -10.1  13.8   260   48   25   8.1   4.4   16.9  62.4     4.6      M    M
 16000   -9.0  15.8   260   50   26   7.2   4.0   16.5  61.7     4.3      M    M
 15500   -7.9  17.8   260   51   26   7.4   4.1   16.1  61.0     3.9      M    M
 15000   -6.9  19.6   260   51   26   6.9   3.8   15.7  60.3     3.5      M    M
 14500   -5.9  21.4   265   49   25   7.1   3.9   15.3  59.5     3.0      M    M
 14000   -4.9  23.2   265   47   24   9.0   4.9   14.9  58.9     2.6      M    M
 13500   -3.5  25.7   265   45   23   9.5   5.2   14.9  58.8     2.6      M    M
 13000   -2.1  28.2   270   44   22  10.0   5.5   14.9  58.8     2.5      M    M
 12500   -0.6  30.9   270   44   23   9.2   5.0   14.9  58.8     2.6      M    M
 12000    0.8  33.4   270   44   23   7.8   4.3   14.8  58.7     2.5      M    M
 11750    1.3  34.3   265   43   22   5.4   3.0   14.5  58.1     2.2      M    M
 11500    1.7  35.1   265   43   22   6.9   3.8   14.2  57.6     1.9      M    M
 11250    2.4  36.3   265   42   22  11.6   6.4   14.2  57.5     1.9      M    M
 11000    3.1  37.6   265   41   21   4.5   2.5   14.2  57.6     1.9      M    M
 10750    3.0  37.4   265   39   20  -3.9  -2.1   13.3  55.9     1.1      M    M
 10500    2.7  36.9   260   36   19  -4.2  -2.3   12.3  54.1     0.1      M    M
 10250    2.5  36.5   255   34   17   0.8   0.5   11.3  52.3    -0.9    282  1.4
 10000    2.6  36.7   250   32   16  -4.9  -2.7   10.6  51.2    -1.6    272  1.4
  9750    1.6  34.9   245   29   15 -15.6  -8.6    8.9  48.0    -3.3    294  1.5
  9500    0.6  33.1   240   28   14 -11.6  -6.4    7.1  44.8    -5.0    317  1.6
  9250   -0.4  31.3   230   26   14 -18.8 -10.3    5.3  41.6    -6.8    340  1.7
  9000   -2.0  28.4   220   26   13 -15.0  -8.2    3.0  37.5    -9.1    379  1.9
  8750   -2.6  27.3   215   25   13  -5.4  -2.9    1.7  35.1   -10.4    389  2.0
  8500   -3.1  26.4   205   24   12  -9.2  -5.1    0.4  32.7   -11.7    399  2.0
  8250   -3.7  25.3   195   24   12  -3.4  -1.9   -0.9  30.3   -13.1    408  2.1
  8000   -3.6  25.5   195   22   12   5.1   2.8   -1.5  29.3   -13.7    397  2.0
  7750   -3.2  26.2   190   18    9   4.5   2.5   -1.8  28.7   -14.1    377  1.9
  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 * * * * * *

           04/19/2024 at 0900 MDT          |       04/19/2024 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +0.7        | CAPE...    +1.1    LI...       -0.1
CINH...     0.0    K Index... +12.0        | CINH...    -3.8    K Index... +12.6
                                           |
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 -58.7 -73.7  260  59 30   1.5   0.8 | -58.5 -73.3  265  57 29   1.2   0.6
 45000 -56.7 -70.1  255  66 34  -1.8  -1.0 | -56.9 -70.4  255  67 34  -2.0  -1.1
 40000 -58.9 -74.0  255  70 36  -1.5  -0.9 | -59.8 -75.6  255  68 35  -2.0  -1.1
 38000 -57.2 -71.0  255  70 36   5.8   3.2 | -57.9 -72.2  255  69 35   6.5   3.6
 36000 -53.2 -63.8  255  69 36   5.8   3.2 | -53.5 -64.3  250  70 36   6.5   3.6
 34000 -49.6 -57.3  255  65 33   6.6   3.6 | -49.4 -56.9  250  69 35   7.2   4.0
 32000 -45.6 -50.1  255  54 28   6.6   3.6 | -45.1 -49.2  255  64 33   7.2   3.9
 30000 -41.2 -42.2  250  47 24   8.3   4.6 | -40.8 -41.4  255  60 31   7.4   4.1
 29000 -38.8 -37.8  250  48 25   8.3   4.6 | -38.5 -37.3  255  59 31   7.4   4.1
 28000 -36.3 -33.3  255  48 25   8.3   4.6 | -36.3 -33.3  255  58 30   7.4   4.1
 27000 -33.8 -28.8  255  48 25   8.7   4.8 | -34.0 -29.2  255  58 30   8.2   4.5
 26000 -31.2 -24.2  255  49 25   8.7   4.8 | -31.6 -24.9  260  56 29   8.2   4.5
 25000 -28.6 -19.5  255  49 25   8.7   4.8 | -29.1 -20.4  260  55 29   8.2   4.5
 24000 -26.0 -14.8  260  50 26   6.8   3.8 | -26.7 -16.1  260  54 28   7.8   4.3
 23000 -24.4 -11.9  260  49 25   5.4   2.9 | -24.5 -12.1  260  54 28   7.5   4.1
 22000 -22.8  -9.0  260  48 25   5.4   2.9 | -22.3  -8.1  265  54 28   7.5   4.1
 21000 -21.2  -6.2  265  47 24   6.5   3.6 | -19.6  -3.3  265  53 28   6.0   3.3
 20000 -18.7  -1.7  265  48 25   6.6   3.6 | -17.9  -0.2  265  53 27   6.0   3.3
 19500 -17.7   0.1  265  49 25   6.6   3.6 | -17.0   1.4  270  53 27   6.0   3.3
 19000 -16.7   1.9  265  49 25   6.6   3.6 | -16.1   3.0  270  53 27   6.0   3.3
 18500 -15.7   3.7  265  49 25   7.5   4.1 | -15.1   4.8  270  52 27   6.5   3.6
 18000 -14.6   5.7  265  48 25   7.4   4.1 | -14.1   6.6  270  51 26   6.5   3.5
 17500 -13.5   7.7  265  47 24   7.4   4.1 | -13.2   8.2  270  50 26   6.4   3.5
 17000 -12.4   9.7  270  44 23   7.5   4.1 | -12.2  10.0  270  48 25   6.4   3.5
 16500 -11.3  11.7  270  42 21   7.6   4.2 | -11.3  11.7  270  47 24   6.5   3.6
 16000 -10.1  13.8  270  40 20   8.1   4.4 | -10.3  13.5  270  44 23   7.2   3.9
 15500  -8.8  16.2  270  37 19   8.2   4.5 |  -9.3  15.3  270  42 21   7.1   3.9
 15000  -7.7  18.1  270  36 19   7.5   4.1 |  -8.2  17.2  270  38 20   8.6   4.7
 14500  -6.6  20.1  270  35 18   7.6   4.2 |  -7.0  19.4  270  35 18   8.6   4.7
 14000  -5.4  22.3  270  35 18   7.8   4.3 |  -5.8  21.6  270  31 16   8.2   4.5
 13500  -4.3  24.3  275  36 18   7.9   4.3 |  -4.6  23.7  265  28 14   8.1   4.4
 13000  -3.1  26.4  275  36 19   9.7   5.3 |  -3.5  25.7  265  25 13   7.8   4.3
 12500  -1.7  28.9  280  35 18   8.7   4.8 |  -2.2  28.0  265  22 11   9.0   4.9
 12000  -0.5  31.1  280  32 17   7.8   4.3 |  -0.9  30.4  265  20 10   8.7   4.8
 11750   0.0  32.0  280  31 16   6.7   3.7 |  -0.3  31.5  265  18 10   8.7   4.8
 11500   0.6  33.1  280  30 15   8.0   4.4 |   0.4  32.7  265  17  9   7.7   4.2
 11250   1.3  34.3  280  28 14  10.8   5.9 |   0.9  33.6  265  15  8   8.3   4.6
 11000   2.0  35.6  285  26 13   5.9   3.2 |   1.5  34.7  265  13  7   3.1   1.7
 10750   2.1  35.8  285  25 13   1.7   1.0 |   1.4  34.5  265  11  6  -1.9  -1.1
 10500   2.3  36.1  280  23 12   1.2   0.7 |   1.3  34.3  265  10  5  -1.7  -1.0
 10250   2.5  36.5  280  22 11   7.4   4.1 |   1.3  34.3  265   8  4   3.5   1.9
 10000   3.1  37.6  280  20 11   1.1   0.6 |   1.7  35.1  265   6  3   1.0   0.6
  9750   2.5  36.5  275  19 10  -9.9  -5.4 |   1.4  34.5  245   4  2  -5.4  -2.9
  9500   1.9  35.4  270  17  9  -7.9  -4.3 |   1.0  33.8  220   4  2  -5.2  -2.8
  9250   1.4  34.5  265  15  8  -5.0  -2.7 |   0.7  33.3  190   4  2   0.5   0.3
  9000   1.1  34.0  255  14  7  -5.0  -2.7 |   1.2  34.2  165   6  3   9.4   5.2
  8750   0.5  32.9  235  11  6  -8.4  -4.6 |   1.9  35.4  160   6  3   9.6   5.2
  8500  -0.1  31.8  210  10  5  -9.0  -4.9 |   2.6  36.7  155   6  3   9.6   5.3
  8250  -0.7  30.7  190  12  6  -3.2  -1.8 |   3.3  37.9  150   7  3   9.2   5.1
  8000  -0.3  31.5  185  11  6  13.3   7.3 |   4.2  39.6  150   7  3  17.2   9.4
  7750   1.1  34.0  180  11  5  22.0  12.1 |   6.1  43.0  145   7  3  31.3  17.2
  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

           04/19/2024 at 1500 MDT          |       04/19/2024 at 1800 MDT
                                           |
CAPE...    +3.6    LI...       -0.6        | CAPE...   +13.8    LI...       +1.0
CINH...     0.0    K Index... +19.0        | CINH...     0.0    K Index... +13.7
                                           |
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 -57.5 -71.5  265  52 27   1.3   0.7 | -57.1 -70.8  265  47 24   1.4   0.8
 45000 -55.6 -68.1  260  63 32  -1.3  -0.7 | -55.2 -67.4  260  58 30  -2.1  -1.1
 40000 -57.5 -71.5  250  71 37  -1.3  -0.7 | -58.5 -73.3  260  78 40  -2.2  -1.2
 38000 -55.9 -68.6  250  73 38   4.5   2.5 | -57.2 -71.0  260  81 42   4.5   2.5
 36000 -53.2 -63.8  250  74 38   4.5   2.5 | -54.5 -66.1  260  79 41   4.5   2.5
 34000 -50.1 -58.2  250  72 37   6.7   3.7 | -51.5 -60.7  260  75 39   6.2   3.4
 32000 -46.1 -51.0  255  67 35   6.7   3.7 | -47.7 -53.9  260  66 34   6.2   3.4
 30000 -41.8 -43.2  255  63 32   7.9   4.3 | -43.3 -45.9  265  58 30   9.5   5.2
 29000 -39.5 -39.1  260  61 32   7.9   4.3 | -40.5 -40.9  265  57 29   9.6   5.2
 28000 -37.1 -34.8  260  60 31   7.9   4.3 | -37.6 -35.7  265  56 29   9.6   5.3
 27000 -34.8 -30.6  260  59 30   7.9   4.4 | -34.8 -30.6  265  54 28   8.6   4.7
 26000 -32.4 -26.3  265  59 31   8.0   4.4 | -32.3 -26.1  265  55 28   8.5   4.6
 25000 -30.0 -22.0  265  60 31   8.0   4.4 | -29.8 -21.6  265  55 28   8.5   4.6
 24000 -27.6 -17.7  265  61 31   7.8   4.3 | -27.3 -17.1  265  55 28   8.2   4.5
 23000 -25.4 -13.7  265  60 31   7.5   4.1 | -24.9 -12.8  265  54 28   8.0   4.4
 22000 -22.6  -8.7  270  58 30   7.5   4.1 | -21.9  -7.4  260  52 27   8.0   4.4
 21000 -20.5  -4.9  270  57 29   6.8   3.7 | -19.7  -3.5  260  52 27   6.9   3.8
 20000 -18.5  -1.3  265  55 28   6.8   3.7 | -17.6   0.3  260  52 27   6.9   3.8
 19500 -17.4   0.7  265  53 27   6.8   3.7 | -16.6   2.1  260  52 27   6.9   3.8
 19000 -16.4   2.5  265  52 27   6.7   3.7 | -15.6   3.9  255  52 27   6.9   3.8
 18500 -15.4   4.3  265  50 26   7.8   4.3 | -14.6   5.7  255  52 27   6.7   3.7
 18000 -14.2   6.4  265  46 24   7.8   4.3 | -13.6   7.5  255  52 27   6.8   3.7
 17500 -13.1   8.4  260  42 22   7.6   4.2 | -12.6   9.3  255  52 27   7.1   3.9
 17000 -12.1  10.2  260  39 20   7.5   4.1 | -11.5  11.3  255  50 26   7.4   4.0
 16500 -11.0  12.2  255  36 18   7.6   4.2 | -10.4  13.3  250  49 25   7.6   4.2
 16000  -9.8  14.4  255  33 17   8.6   4.7 |  -9.1  15.6  250  46 24   9.4   5.1
 15500  -8.6  16.5  255  31 16   8.5   4.7 |  -7.8  18.0  250  43 22   9.3   5.1
 15000  -7.3  18.9  250  29 15   8.9   4.9 |  -6.4  20.5  245  41 21   8.9   4.9
 14500  -6.0  21.2  250  27 14   9.0   4.9 |  -5.1  22.8  245  38 20   9.0   5.0
 14000  -4.7  23.5  250  25 13   6.7   3.7 |  -4.0  24.8  240  36 18   3.0   1.6
 13500  -3.9  25.0  245  21 11   5.7   3.1 |  -4.0  24.8  235  32 16   0.3   0.2
 13000  -3.1  26.4  240  17  9   1.6   0.9 |  -4.0  24.8  225  29 15  -4.0  -2.2
 12500  -3.4  25.9  230  11  6  -2.6  -1.4 |  -5.2  22.6  205  20 10  -5.3  -2.9
 12000  -3.9  25.0  210   6  3  -3.3  -1.8 |  -5.9  21.4  190  15  8  -1.1  -0.6
 11750  -4.2  24.4  190   4  2  -4.9  -2.7 |  -5.7  21.7  180  14  7   4.6   2.5
 11500  -4.5  23.9  140   3  2  -2.0  -1.1 |  -5.4  22.3  170  13  7   3.5   1.9
 11250  -4.5  23.9  090   5  3   1.1   0.6 |  -5.2  22.6  160  13  7   2.8   1.5
 11000  -4.3  24.3  075   8  4   5.2   2.9 |  -5.0  23.0  145  14  7   2.3   1.3
 10750  -3.7  25.3  075   9  5   9.2   5.0 |  -4.8  23.4  135  12  6   2.4   1.3
 10500  -3.1  26.4  070   9  5   8.2   4.5 |  -4.6  23.7  120  11  5   2.3   1.3
 10250  -2.4  27.7  070   9  5   9.6   5.3 |  -4.5  23.9  105  10  5   2.7   1.5
 10000  -1.6  29.1  065  10  5  10.3   5.6 |  -4.3  24.3  085  10  5   2.3   1.3
  9750  -0.9  30.4  060  10  5   9.7   5.3 |  -4.1  24.6  065  10  5   1.6   0.9
  9500  -0.2  31.6  055  10  5   9.7   5.3 |  -4.0  24.8  050  11  5   1.8   1.0
  9250   0.6  33.1  055  11  5  10.2   5.6 |  -3.9  25.0  035  12  6   1.7   1.0
  9000   1.3  34.3  050  11  6  10.4   5.7 |  -3.6  25.5  030  13  7   5.4   2.9
  8750   2.1  35.8  050  11  6  10.1   5.5 |  -3.1  26.4  020  14  7   8.1   4.5
  8500   2.8  37.0  050  11  6   9.9   5.4 |  -2.6  27.3  015  15  8   7.3   4.0
  8250   3.6  38.5  045  11  6  11.0   6.0 |  -2.0  28.4  010  15  8   8.0   4.4
  8000   4.7  40.5  045  11  6  18.6  10.2 |  -1.3  29.7  005  15  8  12.8   7.0
  7750   6.4  43.5  045  11  5  27.5  15.1 |  -0.1  31.8  005  13  7  19.3  10.6
  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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