Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 190112
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1912 MDT Monday, May 18, 2015

This forecast is for Tuesday, May 19, 2015:

If the trigger temperature of 53.9 F/12.2 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5795 ft MSL (488 ft AGL)

Forecast maximum temperature................... 48.0 F/9.3 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. None
Thermal soaring outlook for Wednesday 05/20.... 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)................ Weak PVA
Potential height of wave....................... 14662 ft MSL (9355 ft AGL)
Wave soaring outlook for Wednesday 05/20....... Fair

Remarks...

Sunrise/Sunset.................... 05:41:44 / 20:10:00 MDT
Total possible sunshine........... 14 hr 28 min 16 sec (868 min 16 sec)
Altitude of sun at 12:56:04 MDT... 70.04 degrees

Upper air data from numerical model forecast valid on 05/19/2015 at 0600 MDT

Freezing level.................. 10560 ft MSL (5253 ft AGL)
Convective condensation level... 7868 ft MSL (2561 ft AGL)
Lifted condensation level....... 7507 ft MSL (2201 ft AGL)
Lifted index.................... +8.7
K index......................... +21.3

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  -57.7 -71.9   250   32   17   0.6   0.3      M     M       M      M    M
 45000  -57.4 -71.3   235   41   21  -4.3  -2.4      M     M       M      M    M
 40000  -64.1 -83.4   170   57   29  -4.5  -2.4      M     M       M      M    M
 38000  -59.9 -75.8   165   56   29  10.2   5.6      M     M       M      M    M
 36000  -53.8 -64.8   160   49   25  10.2   5.6      M     M       M      M    M
 34000  -47.9 -54.2   160   45   23   9.2   5.0      M     M       M      M    M
 32000  -41.7 -43.1   160   42   22   9.2   5.0      M     M       M      M    M
 30000  -36.6 -33.9   160   40   21   8.0   4.4   39.9 103.8    23.4      M    M
 29000  -34.2 -29.6   165   39   20   8.0   4.4   39.2 102.6    23.1      M    M
 28000  -31.8 -25.2   170   38   19   8.0   4.4   38.6 101.5    23.0      M    M
 27000  -29.6 -21.3   170   36   19   7.0   3.9   37.8 100.0    22.6      M    M
 26000  -27.5 -17.5   175   35   18   7.0   3.9   36.7  98.0    21.9      M    M
 25000  -25.4 -13.7   180   34   17   7.0   3.9   35.7  96.3    21.4      M    M
 24000  -23.3  -9.9   185   33   17   6.7   3.7   34.7  94.5    20.8      M    M
 23000  -21.3  -6.3   190   32   16   6.7   3.7   33.5  92.4    20.1      M    M
 22000  -19.3  -2.7   195   32   16   6.8   3.7   32.5  90.5    19.4      M    M
 21000  -17.4   0.7   200   31   16   6.4   3.5   31.4  88.5    18.7      M    M
 20000  -15.5   4.1   200   31   16   6.5   3.6   30.2  86.3    17.8      M    M
 19500  -14.5   5.9   200   31   16   6.5   3.6   29.6  85.3    17.4      M    M
 19000  -13.6   7.5   200   32   16   6.5   3.5   29.1  84.4    17.0      M    M
 18500  -12.6   9.3   200   31   16   6.8   3.7   28.6  83.5    16.6      M    M
 18000  -11.6  11.1   200   31   16   6.7   3.7   28.1  82.5    16.2      M    M
 17500  -10.6  12.9   200   31   16   6.2   3.4   27.6  81.6    15.9      M    M
 17000   -9.5  14.9   200   31   16   5.3   2.9   26.4  79.6    15.0      M    M
 16500   -8.7  16.3   200   32   16   6.2   3.4   25.7  78.3    14.4      M    M
 16000   -7.7  18.1   195   32   16   6.8   3.7   25.2  77.4    14.0      M    M
 15500   -6.7  19.9   190   32   16   6.6   3.6   24.7  76.5    13.6      M    M
 15000   -5.9  21.4   190   32   17   5.1   2.8   24.0  75.3    13.0      M    M
 14500   -5.1  22.8   190   33   17   5.2   2.8   23.3  73.9    12.4      M    M
 14000   -4.3  24.3   185   33   17   5.9   3.2   22.6  72.7    11.8      M    M
 13500   -3.5  25.7   180   33   17   6.0   3.3   22.0  71.5    11.2      M    M
 13000   -2.7  27.1   180   33   17   4.6   2.6   21.2  70.2    10.6      M    M
 12500   -2.1  28.2   175   33   17   4.6   2.5   20.4  68.7     9.9      M    M
 12000   -1.4  29.5   175   33   17   4.9   2.7   19.6  67.3     9.1      M    M
 11500   -0.7  30.7   170   32   16   5.1   2.8   18.8  65.9     8.4      M    M
 11000   -0.1  31.8   170   31   16   1.7   0.9   17.9  64.2     7.6      M    M
 10500    0.0  32.0   170   30   15   1.3   0.7   16.5  61.7     6.3      M    M
 10250    0.1  32.2   170   30   15   0.3   0.2   15.8  60.5     5.7      M    M
 10000    0.1  32.2   170   29   15   0.2   0.1   15.0  59.1     5.0      M    M
  9750    0.2  32.4   170   28   15   1.0   0.6   14.3  57.8     4.3      M    M
  9500    0.2  32.4   170   27   14   0.8   0.4   13.6  56.5     3.6      M    M
  9250    0.3  32.5   170   26   14   0.8   0.4   12.9  55.3     3.0      M    M
  9000    0.4  32.7   175   26   13   0.8   0.4   12.2  54.0     2.3      M    M
  8750    0.4  32.7   175   24   13   0.7   0.4   11.5  52.8     1.7      M    M
  8500    0.5  32.9   175   23   12   1.2   0.7   10.8  51.5     1.0      M    M
  8250    0.8  33.4   180   22   11   8.1   4.5   10.4  50.7     0.6      M    M
  8000    1.6  34.9   180   21   11  12.7   6.9   10.5  51.0     0.7      M    M
  7750    2.5  36.5   180   20   11  15.3   8.4   10.8  51.4     0.9      M    M
  7500    3.7  38.7   180   20   10  14.6   8.0   11.3  52.3     1.3      M    M
  7250    4.5  40.1   180   18    9   9.3   5.1   11.4  52.5     1.4      M    M
  7000    5.2  41.4   180   17    9   9.3   5.1   11.4  52.5     1.3      M    M
  6750    5.8  42.4   180   16    8   9.0   5.0   11.3  52.4     1.2      M    M
  6500    6.4  43.5   175   15    8   6.6   3.6   11.2  52.2     1.1      M    M
  6250    6.7  44.1   175   12    6   5.2   2.8   10.9  51.6     0.7      M    M
  6000    7.1  44.8   170   10    5   5.5   3.0   10.6  51.0     0.4      M    M
  5750    7.5  45.5   165    8    4   4.9   2.7   10.2  50.4     0.0      M    M
  5500    7.8  46.0   155    6    3   5.5   3.0    9.9  49.8    -0.4      M    M

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

           05/19/2015 at 0900 MDT          |       05/19/2015 at 1200 MDT
                                           |
K index... +22.5  LI... +272.9             | K index... +25.4  LI... +273.1
CAPE... +35.2  CIN... -64.3                | CAPE... +15.4  CIN... -14.2
                                           |
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 -57.2 -71.0  245  27 14   0.6   0.3 | -56.5 -69.7  245  23 12   1.5   0.8
 45000 -56.5 -69.7  230  38 20  -1.1  -0.6 | -54.4 -65.9  235  37 19  -0.3  -0.1
 40000 -58.2 -72.8  195  55 28  -1.0  -0.5 | -54.8 -66.6  210  54 28  -0.3  -0.1
 38000 -56.2 -69.2  190  60 31   5.2   2.8 | -53.6 -64.5  205  59 31   3.2   1.8
 36000 -53.1 -63.6  190  63 32   5.2   2.8 | -51.7 -61.1  200  64 33   3.2   1.8
 34000 -49.2 -56.6  185  66 34   9.2   5.1 | -49.0 -56.2  195  68 35   7.8   4.3
 32000 -42.9 -45.2  180  67 35   9.2   5.1 | -43.6 -46.5  195  73 37   7.9   4.3
 30000 -38.1 -36.6  180  68 35   6.6   3.6 | -39.2 -38.6  195  72 37   6.3   3.5
 29000 -36.1 -33.0  185  67 35   6.6   3.6 | -37.3 -35.1  195  69 36   6.3   3.5
 28000 -34.1 -29.4  185  67 35   6.6   3.6 | -35.5 -31.9  195  66 34   6.3   3.5
 27000 -32.1 -25.8  185  66 34   6.6   3.6 | -33.6 -28.5  200  61 32   6.1   3.4
 26000 -30.2 -22.4  185  62 32   6.6   3.6 | -31.7 -25.1  200  55 28   6.2   3.4
 25000 -28.2 -18.8  185  58 30   6.6   3.6 | -29.9 -21.8  205  48 25   6.2   3.4
 24000 -26.3 -15.3  185  54 28   5.9   3.2 | -28.1 -18.6  210  41 21   7.0   3.8
 23000 -24.6 -12.3  190  49 25   5.7   3.1 | -25.9 -14.6  205  36 19   7.4   4.1
 22000 -22.9  -9.2  200  44 23   5.7   3.1 | -23.6 -10.5  200  31 16   7.5   4.1
 21000 -21.0  -5.8  205  40 21   8.6   4.7 | -21.5  -6.7  195  27 14   7.1   3.9
 20000 -18.5  -1.3  210  35 18   8.3   4.6 | -19.4  -2.9  190  24 13   7.1   3.9
 19500 -17.3   0.9  215  32 17   8.3   4.6 | -18.3  -0.9  185  23 12   7.1   3.9
 19000 -16.1   3.0  215  30 15   8.3   4.6 | -17.3   0.9  180  23 12   7.1   3.9
 18500 -14.8   5.4  220  27 14   8.5   4.6 | -16.2   2.8  175  22 11   7.8   4.3
 18000 -13.6   7.5  220  24 12   8.5   4.7 | -15.0   5.0  170  22 11   8.1   4.4
 17500 -12.4   9.7  220  20 10   8.3   4.6 | -13.8   7.2  170  21 11   8.1   4.5
 17000 -11.2  11.8  215  19 10   7.6   4.2 | -12.6   9.3  170  21 11   8.3   4.5
 16500  -9.5  14.9  215  19 10   7.5   4.1 | -10.8  12.6  175  21 11   7.7   4.2
 16000  -8.5  16.7  210  18  9   7.2   3.9 |  -9.8  14.4  185  21 11   6.3   3.4
 15500  -7.4  18.7  205  17  9   7.1   3.9 |  -8.9  16.0  190  21 11   6.3   3.5
 15000  -6.4  20.5  205  15  8   6.7   3.7 |  -8.0  17.6  195  22 11   5.9   3.2
 14500  -5.5  22.1  205  14  7   6.7   3.7 |  -7.1  19.2  200  22 12   5.9   3.2
 14000  -4.5  23.9  210  13  7   6.9   3.8 |  -6.2  20.8  205  23 12   6.6   3.6
 13500  -3.5  25.7  210  14  7   6.9   3.8 |  -5.3  22.5  210  24 12   6.6   3.6
 13000  -2.5  27.5  215  15  8   6.9   3.8 |  -4.3  24.3  215  24 12   6.9   3.8
 12500  -1.6  29.1  215  17  9   7.0   3.8 |  -3.3  26.1  215  24 12   6.9   3.8
 12000  -0.7  30.7  215  19 10   3.6   2.0 |  -2.2  28.0  220  23 12   7.4   4.0
 11500  -0.4  31.3  215  20 10   2.5   1.4 |  -1.1  30.0  225  23 12   7.6   4.1
 11000  -0.1  31.8  215  20 10   2.0   1.1 |  -0.1  31.8  225  23 12   4.9   2.7
 10500   0.2  32.4  200  21 11   2.3   1.2 |   0.4  32.7  225  22 11   4.0   2.2
 10250   0.3  32.5  195  22 11   0.4   0.2 |   0.6  33.1  225  21 11   1.5   0.8
 10000   0.3  32.5  190  23 12   2.4   1.3 |   0.7  33.3  225  21 11   3.0   1.6
  9750   0.7  33.3  185  23 12   5.5   3.0 |   1.0  33.8  220  21 11   6.3   3.5
  9500   1.0  33.8  180  24 12   5.1   2.8 |   1.4  34.5  210  21 11   5.7   3.1
  9250   1.4  34.5  175  25 13   3.6   2.0 |   1.8  35.2  205  21 11   5.1   2.8
  9000   1.5  34.7  170  24 12   2.4   1.3 |   2.1  35.8  200  22 11   3.1   1.7
  8750   1.8  35.2  170  22 11   4.3   2.4 |   2.3  36.1  190  24 12   2.5   1.4
  8500   2.1  35.8  165  21 11   4.8   2.6 |   2.4  36.3  185  25 13   2.0   1.1
  8250   2.5  36.5  160  19 10   5.0   2.8 |   2.6  36.7  175  27 14   4.1   2.3
  8000   2.9  37.2  155  18  9   5.6   3.1 |   3.0  37.4  170  26 13   6.7   3.7
  7750   3.3  37.9  150  16  8   5.7   3.1 |   3.5  38.3  165  25 13   6.4   3.5
  7500   3.7  38.7  140  15  8   6.6   3.6 |   3.9  39.0  160  24 12   7.0   3.8
  7250   4.2  39.6  135  15  7   8.3   4.6 |   4.5  40.1  155  22 11   8.4   4.6
  7000   4.9  40.8  130  14  7   9.4   5.2 |   5.1  41.2  150  21 11   9.3   5.1
  6750   5.5  41.9  120  13  7   7.9   4.3 |   5.8  42.4  145  19 10   8.6   4.7
  6500   6.1  43.0  115  12  6   9.4   5.2 |   6.4  43.5  140  18  9   9.7   5.3
  6250   6.9  44.4  115  11  6  11.8   6.5 |   7.2  45.0  140  18  9  11.2   6.1
  6000   7.7  45.9  110  10  5  10.7   5.9 |   8.0  46.4  140  17  9  10.9   6.0
  5750   8.5  47.3  105  10  5  12.2   6.7 |   8.8  47.8  135  16  8  10.8   5.9
  5500   9.6  49.3  105  10  5  17.2   9.4 |   9.6  49.3  135  14  7  11.7   6.4

           05/19/2015 at 1500 MDT          |       05/19/2015 at 1800 MDT
                                           |
K index... +20.3  LI... +271.3             | K index... +23.8  LI... +271.7
CAPE... +275.1  CIN... -1.2                | CAPE... +268.8  CIN... M
                                           |
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 -56.2 -69.2  245  22 11   2.1   1.2 | -56.3 -69.3  240  24 12   2.6   1.4
 45000 -53.1 -63.6  240  35 18   0.5   0.3 | -52.6 -62.7  235  32 16   1.3   0.7
 40000 -52.4 -62.3  225  49 25   0.5   0.2 | -50.6 -59.1  235  45 23   1.3   0.7
 38000 -51.2 -60.2  220  53 27   2.8   1.5 | -49.8 -57.6  235  48 25   1.2   0.6
 36000 -49.6 -57.3  215  56 29   2.8   1.5 | -49.1 -56.4  230  50 26   1.2   0.6
 34000 -47.7 -53.9  210  58 30   4.5   2.5 | -48.0 -54.4  230  50 26   3.1   1.7
 32000 -44.7 -48.5  210  54 28   4.4   2.4 | -46.1 -51.0  225  44 23   3.2   1.7
 30000 -41.5 -42.7  210  49 25   7.0   3.8 | -43.4 -46.1  225  38 20   7.6   4.2
 29000 -39.4 -38.9  210  46 24   7.0   3.9 | -41.1 -42.0  230  35 18   7.7   4.2
 28000 -37.3 -35.1  210  42 22   7.1   3.9 | -38.8 -37.8  230  33 17   7.7   4.2
 27000 -35.2 -31.4  210  39 20   7.1   3.9 | -36.5 -33.7  235  30 16   8.2   4.5
 26000 -33.1 -27.6  210  36 19   7.1   3.9 | -33.9 -29.0  240  30 15   8.4   4.6
 25000 -31.0 -23.8  205  33 17   7.1   3.9 | -31.4 -24.5  245  29 15   8.4   4.6
 24000 -28.9 -20.0  200  30 16   7.4   4.1 | -28.9 -20.0  250  29 15   8.2   4.5
 23000 -26.6 -15.9  200  29 15   7.8   4.3 | -26.6 -15.9  250  28 14   7.9   4.4
 22000 -24.3 -11.7  195  29 15   7.8   4.3 | -24.2 -11.6  255  27 14   8.0   4.4
 21000 -22.0  -7.6  190  28 14   7.6   4.2 | -21.9  -7.4  260  26 13   7.5   4.1
 20000 -19.7  -3.5  190  26 13   7.6   4.1 | -19.7  -3.5  260  24 12   7.4   4.1
 19500 -18.6  -1.5  195  25 13   7.6   4.2 | -18.6  -1.5  260  22 12   7.4   4.1
 19000 -17.5   0.5  195  24 12   7.6   4.1 | -17.5   0.5  265  21 11   7.4   4.1
 18500 -16.4   2.5  195  23 12   7.0   3.8 | -16.4   2.5  265  20 10   7.2   4.0
 18000 -15.4   4.3  205  21 11   6.5   3.6 | -15.4   4.3  265  19 10   7.1   3.9
 17500 -14.4   6.1  220  20 10   6.5   3.5 | -13.8   7.2  270  18  9   6.9   3.8
 17000 -12.8   9.0  230  20 10   7.5   4.1 | -12.8   9.0  270  18  9   6.8   3.7
 16500 -11.7  10.9  235  20 10   7.5   4.1 | -11.8  10.8  265  18  9   6.8   3.7
 16000 -10.6  12.9  240  20 10   7.6   4.2 | -10.8  12.6  265  17  9   6.5   3.6
 15500  -9.5  14.9  250  21 11   7.7   4.2 |  -9.9  14.2  265  16  8   6.5   3.6
 15000  -8.4  16.9  255  21 11   6.8   3.7 |  -8.9  16.0  270  16  8   6.5   3.5
 14500  -7.4  18.7  255  21 11   6.9   3.8 |  -8.0  17.6  270  15  8   6.5   3.5
 14000  -6.4  20.5  260  21 11   6.6   3.6 |  -7.0  19.4  270  14  7   6.4   3.5
 13500  -5.5  22.1  260  20 10   6.5   3.6 |  -6.1  21.0  275  14  7   6.4   3.5
 13000  -4.5  23.9  260  20 10   6.5   3.6 |  -5.1  22.8  275  13  7   6.6   3.6
 12500  -3.6  25.5  260  20 10   6.5   3.6 |  -4.2  24.4  275  13  7   6.7   3.7
 12000  -2.6  27.3  255  19 10   6.0   3.3 |  -3.2  26.2  275  13  7   6.5   3.6
 11500  -1.8  28.8  255  18  9   5.6   3.1 |  -2.3  27.9  275  12  6   6.3   3.5
 11000  -1.0  30.2  250  16  8   4.9   2.7 |  -1.3  29.7  275  11  6   6.2   3.4
 10500  -0.4  31.3  245  14  7   3.8   2.1 |  -0.5  31.1  270  10  5   6.6   3.6
 10250  -0.1  31.8  240  12  6   6.9   3.8 |  -0.0  32.0  270  10  5   3.8   2.1
 10000   0.5  32.9  235  11  6   7.9   4.4 |   0.1  32.2  265  10  5   4.1   2.2
  9750   1.0  33.8  230  11  5   5.5   3.0 |   0.6  33.1  260   9  4   7.1   3.9
  9500   1.4  34.5  225  10  5   6.3   3.4 |   1.0  33.8  250   8  4   6.5   3.5
  9250   1.8  35.2  215  10  5   5.6   3.1 |   1.5  34.7  240   7  3   6.2   3.4
  9000   2.2  36.0  205  10  5   6.6   3.6 |   1.9  35.4  230   6  3   6.4   3.5
  8750   2.7  36.9  190  10  5   8.5   4.7 |   2.4  36.3  215   6  3   7.6   4.2
  8500   3.3  37.9  180  10  5   8.3   4.6 |   2.9  37.2  195   6  3   7.8   4.3
  8250   3.8  38.8  170  11  6   9.4   5.1 |   3.5  38.3  180   6  3   7.7   4.2
  8000   4.6  40.3  160  12  6  10.6   5.8 |   4.0  39.2  165   7  3   7.6   4.2
  7750   5.3  41.5  155  12  6   9.8   5.4 |   4.5  40.1  150   7  4   7.7   4.2
  7500   6.0  42.8  150  12  6   9.4   5.2 |   5.1  41.2  140   8  4   7.9   4.3
  7250   6.7  44.1  145  12  6  10.3   5.6 |   5.7  42.3  130   8  4   8.8   4.9
  7000   7.5  45.5  145  12  6  10.9   6.0 |   6.3  43.3  120   9  5   9.6   5.3
  6750   8.3  46.9  145  12  6   9.7   5.3 |   7.0  44.6  110  10  5   8.7   4.8
  6500   9.0  48.2  140  12  6   9.9   5.4 |   7.6  45.7  100  10  5   9.3   5.1
  6250   9.8  49.6  140  11  6  11.4   6.3 |   8.4  47.1  095  11  5  10.7   5.9
  6000  10.6  51.1  140  11  6  11.3   6.2 |   9.2  48.6  090  10  5  10.7   5.9
  5750  11.5  52.7  135  11  6  11.5   6.3 |  10.0  50.0  090  10  5  10.3   5.7
  5500  12.5  54.5  135  11  5  17.9   9.8 |  10.8  51.4  085  10  5  12.3   6.8
________________________________________________________________________________

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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