Soaring Guidance
Issued by NWS Denver/Boulder, CO

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109
UXUS97 KBOU 101330
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0630 MST Sunday, December 10, 2017

This forecast is for Sunday, December 10, 2017:

If the trigger temperature of 57.8 F/14.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 634 ft/min (3.2 m/s)
   Maximum height of thermals.................. 13258 ft MSL (7912 ft AGL)

Forecast maximum temperature................... 65.0 F/18.8 C
Time of trigger temperature.................... 1115 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10400 ft MSL (5053 ft AGL)
Thermal soaring outlook for Monday 12/11....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 24054 ft MSL (18708 ft AGL)
Wave soaring outlook for Monday 12/11.......... Poor

Remarks... A very dry and unseasonably warm air mass will remain over the region
           for at least the next 24 hours.

Sunrise/Sunset.................... 07:10:08 / 16:34:53 MST
Total possible sunshine........... 9 hr 24 min 46 sec (564 min 46 sec)
Altitude of sun at 11:52:30 MST... 27.24 degrees

Upper air data from numerical model forecast valid on 12/10/2017 at 0500 MST

Freezing level.................. 10408 ft MSL (5062 ft AGL)
Convective condensation level... 23547 ft MSL (18201 ft AGL)
Lifted condensation level....... 21257 ft MSL (15911 ft AGL)
Lifted index.................... +4.9
K index......................... -14.2

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  -60.5 -76.9   355  110   57   2.0   1.1      M     M       M      M    M
 45000  -57.6 -71.7   355  106   55  -0.5  -0.3      M     M       M      M    M
 40000  -59.6 -75.3   355  114   59  -1.4  -0.7      M     M       M      M    M
 38000  -59.2 -74.6   360  115   59   2.3   1.3      M     M       M      M    M
 36000  -57.8 -72.0   360  115   59   2.4   1.3      M     M       M      M    M
 34000  -55.2 -67.4   360  113   58   7.3   4.0      M     M       M      M    M
 32000  -50.9 -59.6   360  109   56   7.3   4.0      M     M       M      M    M
 30000  -46.2 -51.2   360  107   55   8.3   4.5   28.8  83.9     7.9      M    M
 29000  -43.8 -46.8   360  107   55   8.3   4.5   28.2  82.7     7.5      M    M
 28000  -41.3 -42.3   360  108   55   8.3   4.5   27.7  81.8     7.2      M    M
 27000  -38.8 -37.8   360  109   56   8.4   4.6   27.2  80.9     6.9      M    M
 26000  -36.3 -33.3   360  111   57   8.4   4.6   26.6  79.8     6.5      M    M
 25000  -33.7 -28.7   360  113   58   8.4   4.6   26.1  79.0     6.2      M    M
 24000  -31.2 -24.2   360  115   59   8.1   4.5   25.7  78.2     5.9      M    M
 23000  -28.8 -19.8   360  116   60   8.2   4.5   25.0  77.0     5.4      M    M
 22000  -26.4 -15.5   360  116   60   8.2   4.5   24.5  76.0     5.0      M    M
 21000  -23.9 -11.0   355  116   60   8.3   4.5   23.9  75.1     4.6      M    M
 20000  -21.4  -6.5   355  116   59   8.3   4.5   23.4  74.0     4.2      M    M
 19500  -19.6  -3.3   355  115   59   8.3   4.5   23.0  73.4     3.9      M    M
 19000  -18.4  -1.1   355  114   59   8.4   4.6   22.8  73.0     3.7      M    M
 18500  -17.1   1.2   355  114   59   8.4   4.6   22.5  72.6     3.5      M    M
 18000  -15.8   3.6   355  113   58   8.4   4.6   22.3  72.2     3.4      M    M
 17500  -14.6   5.7   355  113   58   8.0   4.4   22.0  71.7     3.2      M    M
 17000  -13.4   7.9   360  113   58   8.0   4.4   21.8  71.2     2.9      M    M
 16500  -12.2  10.0   360  113   58   7.6   4.1   21.4  70.6     2.6      M    M
 16000  -11.1  12.0   360  113   58   7.5   4.1   21.0  69.9     2.3      M    M
 15500  -10.0  14.0   360  113   58   7.2   3.9   20.7  69.2     2.0      M    M
 15000   -8.9  16.0   360  113   58   7.0   3.8   20.2  68.4     1.6      M    M
 14500   -7.9  17.8   360  114   59   6.8   3.7   19.7  67.5     1.2      M    M
 14000   -6.9  19.6   360  113   58   6.5   3.6   19.2  66.6     0.7      M    M
 13500   -5.9  21.4   360  113   58   6.4   3.5   18.7  65.7     0.2      M    M
 13000   -5.0  23.0   360  113   58   5.9   3.2   18.1  64.6    -0.3    610  3.1
 12500   -4.1  24.6   360  112   58   5.9   3.3   17.5  63.4    -0.9    569  2.9
 12000   -3.2  26.2   360  110   57   6.3   3.5   16.9  62.4    -1.5    526  2.7
 11500   -2.3  27.9   360  108   56   6.3   3.5   16.3  61.4    -2.0    483  2.5
 11000   -1.3  29.7   360  103   53   6.7   3.7   15.8  60.5    -2.5    439  2.2
 10500   -0.3  31.5   360   96   50   7.1   3.9   15.3  59.6    -2.9    394  2.0
 10250    0.3  32.5   360   94   48   9.0   4.9   15.2  59.4    -3.1    368  1.9
 10000    1.0  33.8   360   92   48   7.9   4.3   15.1  59.3    -3.1    341  1.7
  9750    1.5  34.7   360   90   46   5.7   3.2   14.9  58.8    -3.4    319  1.6
  9500    1.9  35.4   360   87   45   6.7   3.7   14.6  58.3    -3.7    298  1.5
  9250    2.5  36.5   360   92   47   7.3   4.0   14.4  57.9    -3.9    275  1.4
  9000    3.0  37.4   360   98   50   7.7   4.2   14.2  57.6    -4.1    250  1.3
  8750    3.7  38.7   360  103   53   8.8   4.8   14.1  57.4    -4.2    225  1.1
  8500    4.3  39.7   360  108   55   8.8   4.8   14.0  57.3    -4.3    197  1.0
  8250    5.0  41.0   360  105   54   8.2   4.5   13.9  57.1    -4.4    171  0.9
  8000    5.6  42.1   360  102   53   8.4   4.6   13.8  56.9    -4.5    145  0.7
  7750    6.2  43.2   360  100   51   7.9   4.3   13.7  56.7    -4.6    119  0.6
  7500    6.8  44.2   360   80   41   7.9   4.3   13.5  56.4    -4.8     94  0.5
  7250    7.3  45.1   355   46   24   7.2   4.0   13.4  56.1    -5.0     69  0.4
  7000    7.9  46.2   350   12    6  10.1   5.5   13.2  55.8    -5.1     45  0.2
  6750    8.7  47.7   205    6    3   5.3   2.9   13.3  55.9    -5.1     15  0.1
  6500    8.6  47.5   310    5    2  -2.3  -1.3   12.5  54.5    -5.9      9  0.0
  6250    8.6  47.5   330    9    5   0.9   0.5   11.7  53.0    -6.7      3  0.0
  6000    8.5  47.3   340   14    7  -6.3  -3.5   10.9  51.6    -7.6      M    M
  5750    7.1  44.8   210   10    5 -32.1 -17.6    8.8  47.8    -9.7     32  0.2
  5500    3.7  38.7   185   35   18 -54.6 -30.0    4.7  40.4   -13.8    126  0.6

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

           12/10/2017 at 0800 MST          |       12/10/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +5.3        | CAPE...     0.0    LI...       +5.3
CINH...    -0.0    K Index... -19.3        | CINH...    -0.0    K Index... -24.5
                                           |
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 -60.9 -77.6  355 101 52   2.1   1.1 | -60.8 -77.4  355  80 41   1.6   0.9
 45000 -57.8 -72.0  355  99 51  -0.6  -0.3 | -58.5 -73.3  350  61 31  -0.5  -0.3
 40000 -59.7 -75.5  355 115 59  -1.3  -0.7 | -59.9 -75.8  355 105 54  -1.0  -0.5
 38000 -59.2 -74.6  360 117 60   2.7   1.5 | -59.0 -74.2  360 116 60   3.5   1.9
 36000 -57.3 -71.1  360 117 60   2.7   1.5 | -56.6 -69.9  360 122 63   3.5   1.9
 34000 -54.7 -66.5  360 114 59   7.5   4.1 | -53.7 -64.7  360 125 64   7.3   4.0
 32000 -50.2 -58.4  360 108 56   7.5   4.1 | -49.4 -56.9  360 123 64   7.2   4.0
 30000 -45.6 -50.1  360 105 54   8.1   4.5 | -44.9 -48.8  360 121 62   7.8   4.3
 29000 -43.2 -45.8  360 107 55   8.1   4.5 | -42.5 -44.5  360 120 62   7.8   4.3
 28000 -40.7 -41.3  360 108 56   8.1   4.5 | -40.2 -40.4  360 118 61   7.8   4.3
 27000 -38.3 -36.9  360 110 56   7.9   4.4 | -37.9 -36.2  360 117 60   7.7   4.2
 26000 -35.9 -32.6  360 111 57   8.0   4.4 | -35.6 -32.1  360 116 59   7.7   4.2
 25000 -33.5 -28.3  360 112 58   8.0   4.4 | -33.3 -27.9  360 114 59   7.7   4.2
 24000 -31.1 -24.0  360 113 58   8.1   4.4 | -31.0 -23.8  360 113 58   7.9   4.4
 23000 -28.7 -19.7  360 112 58   8.1   4.4 | -28.6 -19.5  360 111 57   7.9   4.4
 22000 -26.3 -15.3  360 112 58   8.1   4.5 | -26.2 -15.2  360 109 56   8.0   4.4
 21000 -23.8 -10.8  360 112 57   8.4   4.6 | -23.8 -10.8  360 108 55   8.4   4.6
 20000 -21.3  -6.3  360 111 57   8.4   4.6 | -20.7  -5.3  360 106 55   8.4   4.6
 19500 -19.5  -3.1  360 111 57   8.4   4.6 | -19.4  -2.9  360 105 54   8.4   4.6
 19000 -18.2  -0.8  360 110 57   8.4   4.6 | -18.2  -0.8  360 105 54   8.4   4.6
 18500 -16.9   1.6  360 110 56   8.4   4.6 | -16.9   1.6  360 105 54   8.4   4.6
 18000 -15.7   3.7  360 109 56   8.3   4.6 | -15.6   3.9  360 105 54   8.3   4.6
 17500 -14.4   6.1  360 108 56   8.2   4.5 | -14.4   6.1  360 104 54   8.0   4.4
 17000 -13.2   8.2  355 107 55   8.2   4.5 | -13.2   8.2  360 104 53   8.1   4.4
 16500 -12.0  10.4  355 106 55   7.7   4.2 | -12.0  10.4  360 103 53   7.5   4.1
 16000 -10.9  12.4  355 105 54   7.7   4.2 | -10.9  12.4  360 101 52   7.5   4.1
 15500  -9.7  14.5  355 104 54   7.2   4.0 |  -9.8  14.4  355  99 51   7.0   3.8
 15000  -8.7  16.3  355 103 53   6.9   3.8 |  -8.8  16.2  355  98 50   6.7   3.7
 14500  -7.6  18.3  355 102 53   6.8   3.7 |  -7.8  18.0  355  97 50   6.5   3.5
 14000  -6.7  19.9  355 101 52   6.4   3.5 |  -6.8  19.8  355  95 49   6.1   3.4
 13500  -5.7  21.7  355  99 51   6.4   3.5 |  -5.9  21.4  355  93 48   6.2   3.4
 13000  -4.7  23.5  355  97 50   6.5   3.6 |  -5.0  23.0  355  90 47   6.4   3.5
 12500  -3.8  25.2  355  95 49   6.5   3.6 |  -4.0  24.8  360  88 45   6.5   3.6
 12000  -2.8  27.0  360  92 47   6.6   3.6 |  -3.0  26.6  360  85 44   7.1   3.9
 11500  -1.8  28.8  360  89 46   6.6   3.6 |  -1.9  28.6  360  83 43   7.1   3.9
 11000  -0.8  30.6  360  87 45   7.1   3.9 |  -0.8  30.6  360  79 41   7.6   4.2
 10500   0.3  32.5  360  86 44   7.3   4.0 |   0.3  32.5  360  74 38   8.0   4.4
 10250   0.9  33.6  360  86 45   8.8   4.8 |   1.0  33.8  360  70 36  10.1   5.5
 10000   1.5  34.7  360  88 45   7.7   4.2 |   1.7  35.1  360  66 34   8.0   4.4
  9750   2.0  35.6  360  91 47   5.7   3.1 |   2.2  36.0  360  54 28   5.3   2.9
  9500   2.4  36.3  360  94 48   6.5   3.5 |   2.6  36.7  355  42 21   6.4   3.5
  9250   3.0  37.4  360  98 51   7.0   3.9 |   3.1  37.6  355  15  8   6.9   3.8
  9000   3.5  38.3  360 104 53   7.3   4.0 |   3.7  38.7  190  13  7   7.4   4.1
  8750   4.1  39.4  360 109 56   8.0   4.4 |   4.3  39.7  185  36 19   8.9   4.9
  8500   4.7  40.5  360 110 56   8.0   4.4 |   4.9  40.8  180  49 25   8.6   4.7
  8250   5.2  41.4  360  73 38   7.6   4.2 |   5.5  41.9  185  48 25   7.8   4.3
  8000   5.8  42.4  355  37 19   7.8   4.3 |   6.1  43.0  185  47 24   8.1   4.4
  7750   6.4  43.5  260   2  1   7.6   4.2 |   6.7  44.1  185  47 24   7.2   4.0
  7500   6.9  44.4  185  23 12   7.3   4.0 |   7.2  45.0  185  33 17   6.7   3.7
  7250   7.5  45.5  185  30 16   6.6   3.6 |   7.7  45.9  190  14  7   6.9   3.8
  7000   8.0  46.4  185  38 20   8.5   4.7 |   8.2  46.8  335   7  4   6.9   3.8
  6750   8.6  47.5  185  29 15   3.3   1.8 |   8.7  47.7  355  26 13   3.8   2.1
  6500   8.5  47.3  205  10  5  -3.2  -1.8 |   8.8  47.8  350  24 12   1.2   0.6
  6250   8.3  46.9  325   8  4   0.1   0.0 |   8.9  48.0  350  22 11   2.6   1.4
  6000   8.2  46.8  345  23 12  -7.9  -4.3 |   9.0  48.2  350  20 10  -0.4  -0.2
  5750   6.7  44.1  245   6  3 -31.1 -17.1 |   9.0  48.2  345   7  4   2.8   1.5
  5500   3.7  38.7  185  32 17 -47.2 -25.9 |   9.7  49.5  190  10  5  15.9   8.7

           12/10/2017 at 1400 MST          |       12/10/2017 at 1700 MST
                                           |
CAPE...     0.0    LI...       +5.3        | CAPE...     0.0    LI...       +5.4
CINH...    -0.1    K Index... -24.5        | CINH...     0.0    K Index... -18.6
                                           |
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 -60.8 -77.4  350  51 26   1.3   0.7 | -61.4 -78.5  350  64 33   1.3   0.7
 45000 -58.9 -74.0  345  51 26  -0.3  -0.2 | -59.5 -75.1  345  61 32   0.0   0.0
 40000 -60.1 -76.2  355  98 51  -0.8  -0.4 | -59.8 -75.6  355  90 46  -0.2  -0.1
 38000 -58.8 -73.8  355 110 57   3.4   1.9 | -58.4 -73.1  355 100 52   3.4   1.9
 36000 -56.8 -70.2  355 114 59   3.4   1.9 | -56.4 -69.5  355 108 55   3.4   1.9
 34000 -53.9 -65.0  360 119 61   7.5   4.1 | -53.5 -64.3  355 113 58   7.1   3.9
 32000 -49.4 -56.9  360 124 64   7.5   4.1 | -49.2 -56.6  360 116 60   7.1   3.9
 30000 -44.6 -48.3  360 100 52   8.8   4.8 | -44.6 -48.3  360 119 61   8.6   4.7
 29000 -41.9 -43.4  360  66 34   8.8   4.8 | -42.0 -43.6  360 120 62   8.6   4.7
 28000 -39.3 -38.7  360  32 17   8.8   4.8 | -39.4 -38.9  360 121 63   8.6   4.7
 27000 -36.7 -34.1  360  20 10   7.6   4.2 | -36.8 -34.2  360 122 63   8.7   4.8
 26000 -34.4 -29.9  360  56 29   7.7   4.2 | -34.2 -29.6  360 122 63   8.7   4.8
 25000 -32.1 -25.8  360  91 47   7.7   4.2 | -31.6 -24.9  360 123 63   8.7   4.8
 24000 -29.8 -21.6  360 118 61   7.2   3.9 | -29.1 -20.4  360 121 62   7.4   4.1
 23000 -27.7 -17.9  360 109 56   7.2   4.0 | -26.8 -16.2  360 116 60   7.5   4.1
 22000 -25.5 -13.9  360 101 52   7.2   4.0 | -24.5 -12.1  360 110 57   7.5   4.1
 21000 -22.7  -8.9  355  94 48   7.9   4.3 | -21.8  -7.2  360 104 54   7.2   4.0
 20000 -20.3  -4.5  355  92 47   7.9   4.3 | -19.6  -3.3  355 100 52   7.2   4.0
 19500 -19.1  -2.4  355  91 47   7.9   4.3 | -18.6  -1.5  355  98 51   7.2   4.0
 19000 -17.9  -0.2  355  90 46   8.1   4.4 | -17.5   0.5  355  97 50   7.4   4.1
 18500 -16.7   1.9  355  90 46   8.2   4.5 | -16.4   2.5  355  97 50   7.5   4.1
 18000 -15.5   4.1  355  90 46   8.2   4.5 | -15.2   4.6  355  97 50   7.5   4.1
 17500 -14.3   6.3  355  90 46   8.1   4.4 | -14.1   6.6  355  97 50   7.8   4.3
 17000 -13.0   8.6  355  90 47   8.1   4.5 | -12.9   8.8  355  98 50   7.8   4.3
 16500 -11.8  10.8  355  91 47   7.7   4.2 | -11.8  10.8  355  99 51   7.5   4.1
 16000 -10.7  12.7  355  90 46   7.6   4.2 | -10.7  12.7  355 100 51   7.4   4.1
 15500  -9.6  14.7  355  90 46   7.2   4.0 |  -9.5  14.9  355 101 52   7.3   4.0
 15000  -8.5  16.7  355  89 46   6.9   3.8 |  -8.5  16.7  355 101 52   7.1   3.9
 14500  -7.5  18.5  355  88 45   6.7   3.7 |  -7.4  18.7  355 102 53   7.1   3.9
 14000  -6.5  20.3  355  86 44   6.1   3.4 |  -6.3  20.7  355 103 53   6.9   3.8
 13500  -5.6  21.9  355  83 43   6.2   3.4 |  -5.3  22.5  355 103 53   6.9   3.8
 13000  -4.7  23.5  355  81 42   6.2   3.4 |  -4.3  24.3  355 103 53   6.5   3.6
 12500  -3.7  25.3  355  79 41   6.3   3.4 |  -3.3  26.1  355 101 52   6.6   3.6
 12000  -2.7  27.1  355  75 39   7.0   3.8 |  -2.3  27.9  355  99 51   6.7   3.7
 11500  -1.7  28.9  355  71 36   7.0   3.9 |  -1.3  29.7  355  97 50   6.8   3.7
 11000  -0.6  30.9  355  63 33   7.9   4.3 |  -0.2  31.6  355  94 49   7.2   4.0
 10500   0.6  33.1  355  55 28   8.1   4.5 |   0.8  33.4  355  91 47   7.4   4.1
 10250   1.3  34.3  355  50 26  10.1   5.5 |   1.4  34.5  355  90 46   9.5   5.2
 10000   2.0  35.6  355  45 23   8.2   4.5 |   2.1  35.8  355  89 46   8.0   4.4
  9750   2.5  36.5  355  37 19   5.6   3.1 |   2.6  36.7  355  87 45   5.7   3.1
  9500   3.0  37.4  355  29 15   6.8   3.7 |   3.1  37.6  355  86 44   6.6   3.6
  9250   3.5  38.3  350  21 11   7.2   4.0 |   3.6  38.5  355  83 43   6.8   3.8
  9000   4.0  39.2  345  13  7   7.7   4.2 |   4.1  39.4  355  80 41   7.4   4.0
  8750   4.7  40.5  330   6  3   8.7   4.8 |   4.7  40.5  355  76 39   8.3   4.6
  8500   5.3  41.5  260   3  2   8.6   4.7 |   5.3  41.5  355  71 36   8.6   4.7
  8250   5.9  42.6  335   7  4   8.1   4.5 |   6.0  42.8  355  66 34   8.4   4.6
  8000   6.5  43.7  350  14  7   8.3   4.5 |   6.6  43.9  355  61 31   8.5   4.7
  7750   7.1  44.8  350  20 10   7.8   4.3 |   7.2  45.0  355  57 29   8.5   4.6
  7500   7.7  45.9  355  26 13   7.3   4.0 |   7.8  46.0  355  54 28   7.8   4.3
  7250   8.2  46.8  355  37 19   7.1   3.9 |   8.4  47.1  355  50 26   7.7   4.2
  7000   8.7  47.7  355  48 25   7.7   4.2 |   9.0  48.2  355  46 23   7.0   3.9
  6750   9.3  48.7  360  51 26   8.0   4.4 |   9.4  48.9  355  41 21   6.3   3.5
  6500   9.9  49.8  360  49 25   7.6   4.2 |   9.9  49.8  355  41 21   6.7   3.7
  6250  10.5  50.9  360  47 24   7.8   4.3 |  10.4  50.7  355  40 21   6.1   3.3
  6000  11.0  51.8  360  45 23   7.5   4.1 |  10.9  51.6  355  40 20   8.2   4.5
  5750  11.7  53.1  360  45 23  10.2   5.6 |  11.3  52.3  360  38 20  -4.1  -2.2
  5500  12.6  54.7  360  45 23  15.4   8.5 |   9.9  49.8  355  13  7 -30.3 -16.6
________________________________________________________________________________

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

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

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

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

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

DEFINITIONS:

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

CINH (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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