Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 181344
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0744 MDT Thursday, May 18, 2017

This forecast is for Thursday, May 18, 2017:

If the trigger temperature of 52.4 F/11.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5307 ft MSL (0 ft AGL)

Forecast maximum temperature................... 40.0 F/4.9 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................. None
Thermal soaring outlook for Friday 05/19....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 16599 ft MSL (11292 ft AGL)
Wave soaring outlook for Friday 05/19.......... Poor

Remarks...

Sunrise/Sunset.................... 05:42:07 / 20:09:34 MDT
Total possible sunshine........... 14 hr 27 min 26 sec (867 min 26 sec)
Altitude of sun at 12:56:02 MDT... 69.93 degrees

Upper air data from rawinsonde observation taken on 05/18/2017 at 0600 MDT

Freezing level.................. 8915 ft MSL (3608 ft AGL)
Convective condensation level... 8745 ft MSL (3438 ft AGL)
Lifted condensation level....... 6274 ft MSL (968 ft AGL)
Lifted index.................... +8.5
K index......................... +22.7

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  -54.5 -66.1   240   20   10   0.7   0.4      M     M       M      M    M
 45000  -53.4 -64.1   235   20   10   0.7   0.4      M     M       M      M    M
 40000  -53.0 -63.4   215   42   22   0.2   0.1      M     M       M      M    M
 38000  -53.2 -63.8   210   44   23  -0.9  -0.5      M     M       M      M    M
 36000  -53.8 -64.8   200   37   19  -0.9  -0.5      M     M       M      M    M
 34000  -54.1 -65.4   185   33   17   5.4   3.0      M     M       M      M    M
 32000  -49.6 -57.3   185   31   16   7.4   4.1      M     M       M      M    M
 30000  -45.1 -49.2   180   29   15   8.6   4.7   30.9  87.7    19.9      M    M
 29000  -42.5 -44.5   180   28   14   8.6   4.7   30.4  86.6    19.7      M    M
 28000  -39.3 -38.7   180   26   14   8.6   4.7   29.8  85.7    19.6      M    M
 27000  -36.7 -34.1   180   25   13   8.7   4.8   29.5  85.2    19.6      M    M
 26000  -34.1 -29.4   180   25   13   9.0   4.9   29.1  84.4    19.5      M    M
 25000  -31.4 -24.5   180   24   12   9.0   4.9   28.8  83.9    19.5      M    M
 24000  -28.7 -19.7   185   23   12   9.1   5.0   28.6  83.6    19.6      M    M
 23000  -26.2 -15.2   180   24   12   7.9   4.4   28.0  82.5    19.3      M    M
 22000  -23.9 -11.0   180   24   12   8.0   4.4   27.4  81.3    19.0      M    M
 21000  -21.5  -6.7   175   25   13   7.7   4.2   26.8  80.3    18.7      M    M
 20000  -19.5  -3.1   180   29   15   6.6   3.6   25.7  78.2    17.9      M    M
 19500  -18.6  -1.5   180   31   16   6.6   3.6   25.1  77.2    17.5      M    M
 19000  -17.6   0.3   180   34   17   6.6   3.6   24.6  76.2    17.1      M    M
 18500  -16.6   2.1   180   36   19   6.6   3.6   24.1  75.3    16.8      M    M
 18000  -15.7   3.7   185   38   20   6.9   3.8   23.6  74.4    16.4      M    M
 17500  -14.7   5.5   185   40   21   6.8   3.8   23.1  73.5    16.0      M    M
 17000  -13.7   7.3   190   41   21   6.6   3.6   22.6  72.6    15.7      M    M
 16500  -12.7   9.1   190   42   22   6.4   3.5   22.0  71.6    15.2      M    M
 16000  -11.8  10.8   190   43   22   6.3   3.5   21.4  70.6    14.7      M    M
 15500  -11.0  12.2   190   42   22   5.1   2.8   20.7  69.3    14.1      M    M
 15000   -9.9  14.2   185   41   21   5.8   3.2   19.6  67.3    13.2      M    M
 14500   -9.0  15.8   180   39   20   6.8   3.8   19.1  66.3    12.8      M    M
 14000   -8.0  17.6   175   37   19   6.8   3.7   18.6  65.5    12.4      M    M
 13500   -7.1  19.2   165   36   18   5.8   3.2   18.0  64.4    11.9      M    M
 13000   -6.2  20.8   160   35   18   6.0   3.3   17.4  63.3    11.3      M    M
 12500   -5.5  22.1   150   35   18   4.1   2.3   16.6  61.9    10.7      M    M
 12000   -4.9  23.2   145   35   18   4.0   2.2   15.8  60.4     9.9      M    M
 11500   -4.1  24.6   140   35   18   7.0   3.8   15.1  59.1     9.3      M    M
 11000   -3.1  26.4   135   35   18   7.1   3.9   14.6  58.3     8.8      M    M
 10500   -2.3  27.9   125   35   18   3.9   2.2   13.9  57.1     8.2      M    M
 10250   -2.0  28.4   125   35   18   4.3   2.4   13.5  56.3     7.8      M    M
 10000   -1.7  28.9   120   34   18   6.0   3.3   13.1  55.6     7.5      M    M
  9750   -1.2  29.8   120   34   17   6.0   3.3   12.9  55.2     7.2      M    M
  9500   -0.8  30.6   115   33   17   4.7   2.6   12.5  54.5     6.9      M    M
  9250   -0.5  31.1   110   32   17   4.9   2.7   12.1  53.8     6.5      M    M
  9000   -0.1  31.8   105   31   16   5.4   3.0   11.7  53.1     6.2      M    M
  8750    0.3  32.5   105   31   16   5.8   3.2   11.4  52.6     5.9      M    M
  8500    0.7  33.3   100   30   16   5.6   3.1   11.1  52.0     5.6      M    M
  8250    1.1  34.0   100   29   15   5.4   2.9   10.8  51.4     5.2      M    M
  8000    1.5  34.7   095   29   15   6.5   3.6   10.5  50.9     4.9      M    M
  7750    2.0  35.6   090   27   14   5.3   2.9   10.2  50.4     4.7      M    M
  7500    2.2  36.0   085   25   13   3.3   1.8    9.8  49.6     4.2      M    M
  7250    2.5  36.5   085   24   12   3.8   2.1    9.3  48.8     3.8      M    M
  7000    2.8  37.0   080   23   12   3.7   2.0    8.9  47.9     3.3      M    M
  6750    3.0  37.4   075   20   10   3.3   1.8    8.4  47.1     2.9      M    M
  6500    3.2  37.8   070   18    9   2.7   1.5    7.9  46.2     2.4      M    M
  6250    3.4  38.1   060   16    8   3.8   2.1    7.4  45.2     1.9      M    M
  6000    3.8  38.8   055   13    7   5.1   2.8    7.0  44.6     1.5      M    M
  5750    4.2  39.6   050   11    6   6.1   3.4    6.7  44.0     1.1      M    M
  5500    4.7  40.5   040    8    4   9.4   5.2    6.5  43.7     1.0      M    M

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

           05/18/2017 at 0900 MDT          |       05/18/2017 at 1200 MDT
                                           |
K index... +22.2  LI... +1.0               | K index... +22.6  LI... +0.2
CAPE... +0.6  CIN... -2.2                  | CAPE... +2.2  CIN... -16.5
                                           |
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 -54.7 -66.5  235  17  9   1.4   0.8 | -54.1 -65.4  230  16  8   1.6   0.9
 45000 -52.6 -62.7  215  18  9   1.3   0.7 | -51.6 -60.9  210  22 11   1.4   0.7
 40000 -51.8 -61.2  205  42 22   0.4   0.2 | -49.8 -57.6  215  33 17   1.2   0.7
 38000 -51.7 -61.1  205  49 25   0.1   0.1 | -49.2 -56.6  210  36 19   0.6   0.3
 36000 -51.6 -60.9  195  53 27   0.1   0.1 | -48.8 -55.8  195  40 20   0.6   0.3
 34000 -51.5 -60.7  190  58 30   2.8   1.5 | -48.5 -55.3  190  44 23   1.0   0.5
 32000 -48.7 -55.7  190  57 29   4.7   2.6 | -47.4 -53.3  185  42 22   1.8   1.0
 30000 -45.8 -50.4  185  56 29   6.9   3.8 | -46.0 -50.8  185  39 20   5.9   3.2
 29000 -42.7 -44.9  185  50 26   8.2   4.5 | -44.2 -47.6  180  34 17   6.1   3.3
 28000 -40.3 -40.5  180  46 24   8.2   4.5 | -42.3 -44.1  175  29 15   6.1   3.3
 27000 -37.8 -36.0  175  42 22   8.2   4.5 | -40.5 -40.9  165  24 12   5.8   3.2
 26000 -35.4 -31.7  175  39 20   8.2   4.5 | -38.0 -36.4  160  23 12   9.3   5.1
 25000 -32.9 -27.2  175  37 19   8.2   4.5 | -35.3 -31.5  155  24 12   9.3   5.1
 24000 -30.5 -22.9  175  35 18   8.2   4.5 | -32.5 -26.5  145  25 13   9.3   5.1
 23000 -28.1 -18.6  175  34 17   8.2   4.5 | -29.9 -21.8  145  26 13   8.6   4.7
 22000 -25.6 -14.1  170  33 17   8.3   4.5 | -27.3 -17.1  145  26 13   8.6   4.7
 21000 -23.1  -9.6  170  33 17   8.1   4.5 | -24.7 -12.5  145  26 13   8.7   4.8
 20000 -21.2  -6.2  170  33 17   6.3   3.5 | -22.6  -8.7  145  25 13   6.9   3.8
 19500 -20.3  -4.5  170  34 17   6.3   3.5 | -21.6  -6.9  145  25 13   6.9   3.8
 19000 -19.3  -2.7  175  34 17   6.3   3.5 | -20.6  -5.1  145  24 13   6.9   3.8
 18500 -18.4  -1.1  175  34 18   6.4   3.5 | -19.5  -3.1  150  24 12   6.8   3.8
 18000 -17.5   0.5  175  34 17   6.5   3.6 | -18.5  -1.3  150  24 12   7.6   4.2
 17500 -16.5   2.3  180  32 17   6.6   3.6 | -17.4   0.7  150  24 12   7.6   4.2
 17000 -15.6   3.9  185  31 16   6.7   3.7 | -16.2   2.8  150  24 12   7.6   4.1
 16500 -14.6   5.7  185  30 15   6.8   3.8 | -15.1   4.8  150  24 13   7.5   4.1
 16000 -13.6   7.5  185  29 15   6.9   3.8 | -14.0   6.8  150  24 13   7.5   4.1
 15500 -12.6   9.3  185  29 15   7.4   4.0 | -12.4   9.7  150  24 12   7.3   4.0
 15000 -11.0  12.2  185  30 16   7.2   3.9 | -11.4  11.5  150  24 12   7.2   4.0
 14500 -10.0  14.0  185  31 16   6.9   3.8 | -10.3  13.5  150  24 12   7.0   3.9
 14000  -9.0  15.8  180  32 16   7.0   3.8 |  -9.3  15.3  150  24 12   7.1   3.9
 13500  -7.9  17.8  175  33 17   7.5   4.1 |  -8.3  17.1  155  25 13   7.2   3.9
 13000  -6.8  19.8  175  34 18   7.6   4.2 |  -7.3  18.9  160  26 13   7.2   4.0
 12500  -5.9  21.4  165  35 18   5.6   3.1 |  -6.3  20.7  160  28 14   6.9   3.8
 12000  -5.1  22.8  160  36 19   6.0   3.3 |  -5.3  22.5  160  29 15   7.4   4.0
 11500  -4.4  24.1  155  38 19   3.2   1.8 |  -4.5  23.9  155  32 17   2.6   1.4
 11000  -3.9  25.0  150  39 20   3.6   2.0 |  -4.1  24.6  145  37 19   3.2   1.7
 10500  -3.4  25.9  140  41 21   3.0   1.7 |  -3.7  25.3  140  41 21   1.9   1.0
 10250  -3.2  26.2  140  41 21   3.0   1.7 |  -3.6  25.5  135  43 22   1.8   1.0
 10000  -2.9  26.8  135  42 21   4.1   2.2 |  -3.4  25.9  130  45 23   3.3   1.8
  9750  -2.6  27.3  130  41 21   4.9   2.7 |  -3.1  26.4  130  46 24   5.4   2.9
  9500  -2.2  28.0  130  41 21   4.6   2.5 |  -2.7  27.1  125  44 23   5.4   2.9
  9250  -1.9  28.6  125  40 21   4.7   2.6 |  -2.3  27.9  125  43 22   5.8   3.2
  9000  -1.6  29.1  120  40 20   4.6   2.5 |  -1.9  28.6  120  41 21   4.1   2.3
  8750  -1.2  29.8  115  39 20   5.2   2.9 |  -1.7  28.9  120  40 20   3.9   2.2
  8500  -0.8  30.6  115  38 20   6.0   3.3 |  -1.3  29.7  120  37 19   5.5   3.0
  8250  -0.4  31.3  110  38 19   5.2   2.8 |  -0.9  30.4  115  34 18   5.0   2.7
  8000   0.0  32.0  110  37 19   7.7   4.2 |  -0.6  30.9  115  32 16   5.6   3.1
  7750   0.7  33.3  105  35 18   8.8   4.8 |  -0.1  31.8  110  29 15   5.8   3.2
  7500   1.2  34.2  105  34 17   7.3   4.0 |   0.2  32.4  105  27 14   5.2   2.9
  7250   1.7  35.1  105  33 17   7.7   4.2 |   0.6  33.1  105  25 13   5.9   3.2
  7000   2.3  36.1  100  32 16   8.2   4.5 |   1.2  34.2  100  24 12   9.5   5.2
  6750   2.9  37.2  100  30 15   7.3   4.0 |   1.9  35.4  100  22 12   9.7   5.3
  6500   3.3  37.9  100  28 14   5.9   3.2 |   2.5  36.5  095  20 11   7.5   4.1
  6250   3.8  38.8  095  26 14   7.1   3.9 |   3.0  37.4  090  19 10   8.4   4.6
  6000   4.3  39.7  095  23 12   8.4   4.6 |   3.7  38.7  090  16  8   8.9   4.9
  5750   4.9  40.8  090  20 11   7.8   4.3 |   4.3  39.7  085  14  7   8.1   4.4
  5500   5.5  41.9  090  17  9   8.1   4.4 |   4.8  40.6  080  11  6   8.3   4.6

           05/18/2017 at 1500 MDT          |       05/18/2017 at 1800 MDT
                                           |
K index... +24.2  LI... +0.1               | K index... +19.2  LI... +1.1
CAPE... +8.6  CIN... -25.7                 | CAPE... +2.0  CIN... -1.2
                                           |
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 -53.5 -64.3  235  20 10   1.9   1.1 | -54.3 -65.7  245  19 10   2.3   1.2
 45000 -50.5 -58.9  230  28 15   1.4   0.7 | -50.7 -59.3  240  26 13   1.7   0.9
 40000 -49.0 -56.2  220  23 12   1.1   0.6 | -48.6 -55.5  215  21 11   1.4   0.8
 38000 -48.2 -54.8  215  22 11   1.6   0.9 | -47.9 -54.2  210  21 11   0.7   0.4
 36000 -47.3 -53.1  205  23 12   1.6   0.9 | -47.4 -53.3  215  22 11   0.8   0.4
 34000 -46.3 -51.3  195  25 13   1.4   0.8 | -47.0 -52.6  215  24 12   0.9   0.5
 32000 -46.0 -50.8  185  18  9   0.4   0.2 | -46.1 -51.0  210  22 12   1.3   0.7
 30000 -45.6 -50.1  150  11  6   3.9   2.1 | -45.2 -49.4  205  21 11   4.0   2.2
 29000 -44.0 -47.2  130   9  5   5.3   2.9 | -43.7 -46.7  200  18  9   4.9   2.7
 28000 -42.4 -44.3  100   9  5   5.3   2.9 | -42.3 -44.1  190  14  7   4.9   2.7
 27000 -40.8 -41.4  080  10  5   5.2   2.8 | -40.8 -41.4  180  11  6   4.8   2.6
 26000 -38.6 -37.5  080  11  6   8.4   4.6 | -38.9 -38.0  175  10  5   7.2   3.9
 25000 -36.1 -33.0  095  11  6   8.4   4.6 | -36.8 -34.2  185   8  4   7.2   3.9
 24000 -33.6 -28.5  110  12  6   8.4   4.6 | -34.6 -30.3  195   7  4   7.2   4.0
 23000 -31.3 -24.3  125  13  7   6.9   3.8 | -32.3 -26.1  200   8  4   8.1   4.4
 22000 -29.3 -20.7  140  16  8   6.9   3.8 | -29.9 -21.8  195   9  5   8.1   4.4
 21000 -27.2 -17.0  150  20 10   6.7   3.7 | -27.5 -17.5  195  11  6   8.1   4.5
 20000 -24.9 -12.8  155  21 11   8.2   4.5 | -25.1 -13.2  195  12  6   8.0   4.4
 19500 -23.7 -10.7  160  22 11   8.2   4.5 | -23.9 -11.0  200  13  7   8.0   4.4
 19000 -22.5  -8.5  160  22 11   8.2   4.5 | -22.7  -8.9  200  13  7   8.1   4.4
 18500 -21.3  -6.3  160  23 12   8.1   4.5 | -21.5  -6.7  205  14  7   8.1   4.4
 18000 -20.0  -4.0  165  23 12   9.0   4.9 | -20.4  -4.7  205  15  8   7.6   4.2
 17500 -18.7  -1.7  165  23 12   9.0   4.9 | -19.3  -2.7  210  16  8   7.6   4.2
 17000 -17.4   0.7  165  22 12   8.7   4.8 | -18.1  -0.6  210  18  9   7.4   4.1
 16500 -16.2   2.8  165  22 11   8.2   4.5 | -16.5   2.3  215  20 10   7.2   4.0
 16000 -14.4   6.1  165  22 11   7.5   4.1 | -15.4   4.3  220  21 11   7.7   4.3
 15500 -13.4   7.9  170  23 12   7.0   3.9 | -14.2   6.4  220  22 11   7.9   4.3
 15000 -12.3   9.9  170  23 12   6.8   3.7 | -13.1   8.4  225  22 12   7.6   4.2
 14500 -11.4  11.5  175  25 13   6.3   3.5 | -12.0  10.4  225  22 11   7.1   3.9
 14000 -10.5  13.1  175  26 14   6.4   3.5 | -11.0  12.2  225  22 11   6.8   3.8
 13500  -9.5  14.9  180  28 14   6.4   3.5 | -10.1  13.8  225  20 10   5.7   3.1
 13000  -8.6  16.5  180  29 15   6.4   3.5 |  -9.3  15.3  225  19 10   5.7   3.1
 12500  -7.7  18.1  175  29 15   6.7   3.7 |  -8.6  16.5  225  17  9   4.8   2.6
 12000  -6.7  19.9  170  29 15   6.8   3.8 |  -7.9  17.8  220  16  8   4.9   2.7
 11500  -5.8  21.6  165  28 15   5.7   3.1 |  -7.0  19.4  220  14  7   6.3   3.5
 11000  -5.0  23.0  155  28 14   5.9   3.2 |  -6.1  21.0  215  12  6   6.1   3.4
 10500  -4.1  24.6  150  28 14   5.6   3.1 |  -5.4  22.3  215  10  5   4.1   2.2
 10250  -3.7  25.3  145  27 14   5.0   2.8 |  -5.1  22.8  215   9  5   4.0   2.2
 10000  -3.3  26.1  140  27 14   7.6   4.1 |  -4.8  23.4  215   8  4   5.1   2.8
  9750  -2.7  27.1  135  26 13   7.2   3.9 |  -4.4  24.1  215   6  3   5.4   2.9
  9500  -2.4  27.7  135  24 13   4.4   2.4 |  -4.1  24.6  220   5  2   4.3   2.4
  9250  -2.0  28.4  130  23 12   5.1   2.8 |  -3.8  25.2  225   3  2   4.7   2.6
  9000  -1.6  29.1  125  22 11   5.1   2.8 |  -3.4  25.9  245   2  1   4.1   2.3
  8750  -1.3  29.7  120  21 11   4.4   2.4 |  -3.1  26.4  300   2  1   3.9   2.1
  8500  -1.0  30.2  115  19 10   3.8   2.1 |  -2.8  27.0  325   4  2   4.2   2.3
  8250  -0.7  30.7  110  18  9   3.7   2.0 |  -2.5  27.5  335   6  3   4.1   2.2
  8000  -0.4  31.3  100  17  9   4.9   2.7 |  -2.3  27.9  340   8  4   3.1   1.7
  7750  -0.0  32.0  090  15  8   4.9   2.7 |  -2.1  28.2  340  12  6   1.5   0.8
  7500   0.2  32.4  080  14  7   3.6   2.0 |  -2.0  28.4  340  14  7   0.7   0.4
  7250   0.5  32.9  065  14  7   3.8   2.1 |  -1.9  28.6  335  17  9   1.5   0.8
  7000   0.7  33.3  055  14  7   2.2   1.2 |  -1.8  28.8  335  20 10   2.2   1.2
  6750   0.9  33.6  040  14  7   2.5   1.3 |  -1.6  29.1  330  23 12   2.9   1.6
  6500   1.1  34.0  025  14  7   2.4   1.3 |  -1.4  29.5  325  24 12   4.2   2.3
  6250   1.3  34.3  015  15  8   5.4   3.0 |  -1.0  30.2  320  24 12   6.5   3.6
  6000   1.9  35.4  010  14  7   8.9   4.9 |  -0.4  31.3  315  21 11   8.2   4.5
  5750   2.5  36.5  360  14  7   7.9   4.3 |   0.1  32.2  310  19 10   6.9   3.8
  5500   3.1  37.6  360  12  6  11.7   6.4 |   0.7  33.3  305  16  8   9.8   5.4
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

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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