Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 220014
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1714 MST Sunday, December 21, 2014

This forecast is for Monday, December 22, 2014:

If the trigger temperature of 42.2 F/5.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6686 ft MSL (1399 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................. 5345 ft MSL (58 ft AGL)
Thermal soaring outlook for Tuesday 12/23...... Poor

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)................ Weak PVA
Potential height of wave....................... 29619 ft MSL (24332 ft AGL)
Wave soaring outlook for Tuesday 12/23......... Poor

Remarks...

Sunrise/Sunset.................... 07:17:29 / 16:38:56 MST
Total possible sunshine........... 9 hr 21 min 26 sec (561 min 26 sec)
Altitude of sun at 11:58:13 MST... 26.87 degrees

Upper air data from numerical model forecast valid on 12/22/2014 at 0500 MST

Freezing level.................. 6835 ft MSL (1548 ft AGL)
Convective condensation level... 11647 ft MSL (6360 ft AGL)
Lifted condensation level....... 10930 ft MSL (5642 ft AGL)
Lifted index.................... +8.6
K index......................... +14.1

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  -55.4 -67.7   285   25   13   2.3   1.3      M     M       M      M    M
 45000  -52.0 -61.6   285   44   23   2.3   1.3      M     M       M      M    M
 40000  -48.3 -54.9   305   54   28   2.4   1.3      M     M       M      M    M
 38000  -47.0 -52.6   315   59   30   1.6   0.9      M     M       M      M    M
 36000  -46.0 -50.8   320   66   34   1.6   0.9      M     M       M      M    M
 34000  -45.1 -49.2   330   74   38   1.6   0.9      M     M       M      M    M
 32000  -44.0 -47.2   330   79   41   1.7   0.9      M     M       M      M    M
 30000  -43.0 -45.4   330   83   43   1.7   0.9      M     M       M      M    M
 29000  -42.3 -44.1   330   85   44   2.0   1.1   32.2  90.0    21.0      M    M
 28000  -41.7 -43.1   330   85   44   2.0   1.1   29.1  84.4    18.9      M    M
 27000  -41.1 -42.0   330   86   44   2.0   1.1   26.2  79.1    16.9      M    M
 26000  -40.1 -40.2   330   86   44   7.2   3.9   23.8  74.9    15.2      M    M
 25000  -38.1 -36.6   330   84   43   6.7   3.7   22.5  72.6    14.4      M    M
 24000  -36.1 -33.0   330   83   43   6.7   3.7   21.4  70.6    13.6      M    M
 23000  -34.1 -29.4   325   82   42   7.1   3.9   20.4  68.7    13.0      M    M
 22000  -31.9 -25.4   325   82   42   7.1   3.9   19.4  66.8    12.3      M    M
 21000  -29.8 -21.6   325   81   42   7.0   3.9   18.5  65.2    11.7      M    M
 20000  -28.1 -18.6   325   77   40   3.6   2.0   17.0  62.6    10.6      M    M
 19500  -27.6 -17.7   325   72   37   3.7   2.0   15.9  60.6     9.7      M    M
 19000  -27.1 -16.8   325   67   35   3.7   2.0   14.8  58.6     8.8      M    M
 18500  -26.5 -15.7   320   62   32   3.7   2.0   13.8  56.8     7.9      M    M
 18000  -26.0 -14.8   320   58   30   3.7   2.1   12.8  55.0     7.1      M    M
 17500  -25.5 -13.9   320   55   29   3.7   2.0   11.7  53.1     6.2      M    M
 17000  -24.9 -12.8   320   54   28   3.5   1.9   10.7  51.2     5.3      M    M
 16500  -24.2 -11.6   320   52   27   6.0   3.3    9.8  49.7     4.6      M    M
 16000  -23.4 -10.1   320   49   25   5.8   3.2    9.2  48.5     4.0      M    M
 15500  -22.4  -8.3   320   47   24   8.1   4.5    8.6  47.5     3.5      M    M
 15000  -21.1  -6.0   320   45   23   8.9   4.9    8.5  47.2     3.4      M    M
 14500  -19.2  -2.6   320   42   22   7.5   4.1    8.2  46.7     3.1      M    M
 14000  -18.1  -0.6   320   41   21   7.6   4.2    7.8  46.1     2.8      M    M
 13500  -16.9   1.6   320   40   21   8.4   4.6    7.5  45.5     2.6      M    M
 13000  -15.6   3.9   320   39   20   8.5   4.7    7.3  45.2     2.4      M    M
 12500  -14.4   6.1   320   37   19   7.8   4.3    7.1  44.7     2.1      M    M
 12000  -13.3   8.1   320   35   18   7.6   4.2    6.7  44.1     1.8      M    M
 11500  -12.1  10.2   325   32   17   9.0   5.0    6.5  43.7     1.6      M    M
 11000  -10.7  12.7   325   31   16   9.2   5.1    6.4  43.5     1.5      M    M
 10500   -9.4  15.1   325   30   16   8.5   4.7    6.2  43.2     1.4      M    M
 10250   -8.8  16.2   325   30   15   7.7   4.2    6.1  43.0     1.3      M    M
 10000   -8.2  17.2   325   29   15  10.8   5.9    6.0  42.8     1.2      M    M
  9750   -7.3  18.9   325   29   15  10.9   6.0    6.2  43.2     1.3      M    M
  9500   -6.6  20.1   325   27   14   7.8   4.3    6.1  43.0     1.2      M    M
  9250   -6.0  21.2   325   26   13   8.7   4.8    6.0  42.8     1.1      M    M
  9000   -5.4  22.3   325   25   13   8.0   4.4    5.9  42.6     1.0      M    M
  8750   -4.8  23.4   325   24   12   8.0   4.4    5.7  42.3     0.9      M    M
  8500   -4.2  24.4   325   23   12   8.6   4.7    5.6  42.2     0.8      M    M
  8250   -3.5  25.7   325   22   11   8.1   4.5    5.5  42.0     0.7      M    M
  8000   -2.9  26.8   325   21   11   9.4   5.1    5.4  41.8     0.6      M    M
  7750   -2.2  28.0   325   19   10   8.7   4.8    5.4  41.8     0.6      M    M
  7500   -1.6  29.1   325   18    9   7.0   3.8    5.3  41.5     0.4      M    M
  7250   -1.1  30.0   325   17    9   7.6   4.2    5.1  41.1     0.2      M    M
  7000   -0.5  31.1   325   16    8   9.1   5.0    4.9  40.9     0.1      M    M
  6750    0.2  32.4   330   15    8   8.1   4.5    4.9  40.8     0.1      M    M
  6500    0.7  33.3   330   14    7   6.8   3.7    4.7  40.4    -0.2      M    M
  6250    1.2  34.2   330   13    7   5.9   3.2    4.5  40.0    -0.4      M    M
  6000    1.6  34.9   330   11    5   4.6   2.5    4.1  39.4    -0.8      M    M
  5750    1.9  35.4   325    8    4   3.0   1.6    3.7  38.6    -1.2      M    M
  5500    1.8  35.2   300    5    3  -4.3  -2.3    2.9  37.3    -2.0      M    M

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

           12/22/2014 at 0800 MST          |       12/22/2014 at 1100 MST
                                           |
K index... +7.5  LI... +3.3                | K index... +3.4  LI... +3.3
CAPE... +1.1  CIN... -16.5                 | CAPE... 0.0  CIN... -4.7
                                           |
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 -54.8 -66.6  300  21 11   2.0   1.1 | -53.0 -63.4  305  15  7   2.2   1.2
 45000 -51.8 -61.2  305  29 15   2.0   1.1 | -49.6 -57.3  330  18  9   2.2   1.2
 40000 -47.0 -52.6  315  38 20   3.1   1.7 | -44.9 -48.8  320  28 14   3.2   1.8
 38000 -45.4 -49.7  320  45 23   1.4   0.8 | -43.2 -45.8  320  34 18   1.5   0.8
 36000 -44.6 -48.3  325  58 30   1.4   0.8 | -42.3 -44.1  330  49 25   1.5   0.8
 34000 -43.8 -46.8  330  72 37   1.4   0.7 | -41.4 -42.5  335  64 33   1.4   0.8
 32000 -43.2 -45.8  330  80 41   0.8   0.4 | -41.8 -43.2  335  72 37  -1.2  -0.7
 30000 -42.8 -45.0  330  85 44   0.8   0.4 | -42.5 -44.5  335  76 39  -1.2  -0.7
 29000 -42.3 -44.1  330  85 44   1.3   0.7 | -42.6 -44.7  335  76 39   0.2   0.1
 28000 -42.0 -43.6  330  83 43   1.3   0.7 | -42.5 -44.5  330  73 38   0.2   0.1
 27000 -41.6 -42.9  330  81 42   1.3   0.7 | -42.5 -44.5  330  70 36   0.2   0.1
 26000 -40.8 -41.4  330  80 41   6.6   3.6 | -42.2 -44.0  330  68 35   5.1   2.8
 25000 -38.9 -38.0  325  80 41   6.3   3.5 | -40.3 -40.5  330  69 35   6.2   3.4
 24000 -37.1 -34.8  325  81 42   6.4   3.5 | -38.5 -37.3  330  69 36   6.2   3.4
 23000 -35.1 -31.2  325  81 42   7.2   3.9 | -36.6 -33.9  330  70 36   6.9   3.8
 22000 -32.9 -27.2  325  78 40   7.2   4.0 | -34.4 -29.9  330  68 35   7.2   3.9
 21000 -30.8 -23.4  325  75 39   7.2   3.9 | -32.3 -26.1  330  66 34   7.2   3.9
 20000 -29.0 -20.2  325  72 37   4.0   2.2 | -30.3 -22.5  330  63 32   5.1   2.8
 19500 -28.4 -19.1  325  70 36   4.1   2.2 | -29.5 -21.1  325  61 31   5.2   2.9
 19000 -27.7 -17.9  325  68 35   4.1   2.3 | -28.8 -19.8  325  58 30   5.2   2.9
 18500 -27.1 -16.8  325  66 34   4.1   2.3 | -28.0 -18.4  325  56 29   5.2   2.9
 18000 -26.5 -15.7  330  64 33   4.1   2.3 | -27.2 -17.0  325  53 27   5.1   2.8
 17500 -25.9 -14.6  330  62 32   4.1   2.3 | -26.6 -15.9  325  52 27   2.8   1.5
 17000 -25.3 -13.5  330  59 30   4.2   2.3 | -26.2 -15.2  330  52 27   2.7   1.5
 16500 -24.7 -12.5  330  56 29   3.4   1.8 | -25.6 -14.1  330  51 26   5.6   3.0
 16000 -24.3 -11.7  335  52 27   3.3   1.8 | -24.8 -12.6  330  51 26   5.8   3.2
 15500 -23.7 -10.7  335  49 25   6.2   3.4 | -23.2  -9.8  330  49 25   8.7   4.8
 15000 -22.6  -8.7  335  46 24   7.5   4.1 | -22.0  -7.6  330  47 24   8.5   4.7
 14500 -20.8  -5.4  335  43 22   8.4   4.6 | -20.8  -5.4  330  46 24   7.1   3.9
 14000 -19.6  -3.3  335  43 22   8.3   4.5 | -19.8  -3.6  335  46 24   7.0   3.8
 13500 -18.3  -0.9  335  42 22   8.7   4.8 | -18.6  -1.5  335  46 24   8.5   4.7
 13000 -17.0   1.4  330  41 21   8.7   4.8 | -17.3   0.9  335  46 23   8.8   4.8
 12500 -15.7   3.7  330  41 21   9.4   5.1 | -16.1   3.0  335  45 23   8.0   4.4
 12000 -14.3   6.3  330  40 21   9.5   5.2 | -14.9   5.2  335  44 23   7.8   4.3
 11500 -13.0   8.6  330  39 20   8.4   4.6 | -13.7   7.3  335  43 22   8.8   4.8
 11000 -11.8  10.8  325  37 19   8.4   4.6 | -12.4   9.7  330  42 21   9.0   4.9
 10500 -10.5  13.1  325  35 18   8.6   4.7 | -11.1  12.0  330  39 20   8.2   4.5
 10250  -9.9  14.2  325  34 18   8.1   4.4 | -10.5  13.1  330  38 20   7.5   4.1
 10000  -9.3  15.3  325  34 17   9.9   5.4 |  -9.9  14.2  330  37 19  10.2   5.6
  9750  -8.5  16.7  325  32 17  10.3   5.7 |  -9.0  15.8  330  35 18  10.9   6.0
  9500  -7.8  18.0  325  31 16   8.8   4.8 |  -8.4  16.9  330  34 17   8.6   4.7
  9250  -7.1  19.2  325  30 15   9.2   5.0 |  -7.7  18.1  330  32 17   9.4   5.2
  9000  -6.4  20.5  325  29 15   9.2   5.0 |  -7.0  19.4  330  31 16   8.5   4.7
  8750  -5.7  21.7  325  28 14   8.7   4.8 |  -6.4  20.5  330  30 15   8.5   4.7
  8500  -5.1  22.8  325  26 13   8.4   4.6 |  -5.7  21.7  330  28 15   9.3   5.1
  8250  -4.5  23.9  325  25 13   8.2   4.5 |  -5.0  23.0  330  27 14   8.8   4.8
  8000  -3.9  25.0  325  23 12   9.2   5.1 |  -4.4  24.1  330  26 13   9.8   5.4
  7750  -3.2  26.2  325  21 11   8.7   4.8 |  -3.6  25.5  330  24 12   9.0   4.9
  7500  -2.6  27.3  320  20 10   7.2   4.0 |  -3.0  26.6  330  22 11   7.5   4.1
  7250  -2.0  28.4  320  19 10   7.8   4.3 |  -2.5  27.5  325  21 11   8.0   4.4
  7000  -1.4  29.5  320  18  9   8.7   4.8 |  -1.9  28.6  325  19 10   8.6   4.7
  6750  -0.8  30.6  320  16  8   7.8   4.3 |  -1.2  29.8  325  16  8   8.8   4.8
  6500  -0.3  31.5  320  15  8   7.0   3.8 |  -0.6  30.9  325  13  7   8.1   4.4
  6250   0.2  32.4  320  13  7   5.5   3.0 |   0.0  32.0  325  11  6   9.5   5.2
  6000   0.5  32.9  315  11  6   4.0   2.2 |   0.8  33.4  325  10  5  10.9   6.0
  5750   0.8  33.4  305   9  5   3.0   1.6 |   1.6  34.9  325   8  4   9.7   5.3
  5500   0.8  33.4  290   7  4  -3.1  -1.7 |   2.3  36.1  325   7  4  11.1   6.1

           12/22/2014 at 1400 MST          |       12/22/2014 at 1700 MST
                                           |
K index... +11.4  LI... +1.3               | K index... +15.0  LI... +0.6
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... -5.0
                                           |
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 -53.7 -64.7  315  14  7   2.3   1.3 | -54.0 -65.2  310  15  8   2.8   1.5
 45000 -50.0 -58.0  340  20 10   2.4   1.3 | -49.6 -57.3  310  13  7   2.8   1.5
 40000 -44.6 -48.3  290  24 12   3.6   2.0 | -45.5 -49.9  330  33 17   2.7   1.5
 38000 -42.7 -44.9  290  29 15   1.6   0.9 | -43.8 -46.8  335  42 21   3.0   1.7
 36000 -41.8 -43.2  320  40 21   1.6   0.9 | -42.0 -43.6  335  50 26   3.0   1.7
 34000 -40.8 -41.4  330  56 29   1.5   0.8 | -40.2 -40.4  340  59 30   3.0   1.6
 32000 -41.4 -42.5  335  67 34  -2.2  -1.2 | -40.4 -40.7  335  65 34  -2.0  -1.1
 30000 -42.9 -45.2  335  75 39  -2.2  -1.2 | -41.8 -43.2  335  72 37  -1.9  -1.0
 29000 -43.1 -45.6  335  75 39   0.3   0.1 | -42.0 -43.6  330  74 38   0.4   0.2
 28000 -43.0 -45.4  330  73 38   0.3   0.2 | -41.8 -43.2  330  74 38   0.5   0.3
 27000 -42.9 -45.2  330  71 36   0.3   0.2 | -41.7 -43.1  330  75 39   0.5   0.3
 26000 -42.7 -44.9  330  69 35   4.2   2.3 | -41.5 -42.7  330  76 39   2.5   1.4
 25000 -41.0 -41.8  330  68 35   5.7   3.1 | -40.4 -40.7  325  69 36   3.9   2.1
 24000 -39.3 -38.7  330  67 35   5.7   3.2 | -39.2 -38.6  325  63 32   3.9   2.1
 23000 -37.5 -35.5  330  67 34   6.7   3.7 | -38.0 -36.4  325  56 29   3.8   2.1
 22000 -35.3 -31.5  330  63 33   7.2   4.0 | -36.9 -34.4  320  52 27   3.8   2.1
 21000 -33.2 -27.8  330  60 31   7.2   4.0 | -35.8 -32.4  320  47 24   3.8   2.1
 20000 -31.3 -24.3  325  57 29   3.8   2.1 | -34.4 -29.9  315  43 22   7.8   4.3
 19500 -30.7 -23.3  325  55 29   4.1   2.2 | -33.2 -27.8  315  41 21   7.5   4.1
 19000 -30.1 -22.2  325  54 28   4.1   2.3 | -32.1 -25.8  310  39 20   7.5   4.1
 18500 -29.5 -21.1  320  53 27   4.2   2.3 | -31.0 -23.8  310  37 19   7.5   4.1
 18000 -28.9 -20.0  320  52 27   4.3   2.3 | -29.9 -21.8  310  35 18   7.5   4.1
 17500 -28.0 -18.4  320  49 25   7.2   4.0 | -28.7 -19.7  310  34 17   8.8   4.8
 17000 -27.0 -16.6  320  47 24   6.9   3.8 | -27.4 -17.3  315  34 17   8.8   4.8
 16500 -25.9 -14.6  315  45 23   8.2   4.5 | -26.1 -15.0  320  34 17   7.8   4.3
 16000 -24.6 -12.3  315  44 23   8.4   4.6 | -25.0 -13.0  320  33 17   7.7   4.2
 15500 -23.4 -10.1  315  43 22   8.4   4.6 | -23.2  -9.8  325  32 16   9.0   4.9
 15000 -21.5  -6.7  315  41 21   8.4   4.6 | -21.9  -7.4  325  30 15   9.0   4.9
 14500 -20.3  -4.5  320  39 20   7.8   4.3 | -20.6  -5.1  325  28 14   8.0   4.4
 14000 -19.1  -2.4  320  38 19   7.7   4.2 | -19.4  -2.9  325  27 14   8.0   4.4
 13500 -18.0  -0.4  320  36 19   7.9   4.4 | -18.2  -0.8  325  25 13   7.8   4.3
 13000 -16.8   1.8  320  34 18   8.0   4.4 | -17.1   1.2  330  24 13   7.8   4.3
 12500 -15.6   3.9  320  32 16   8.5   4.7 | -15.9   3.4  330  23 12   7.6   4.2
 12000 -14.3   6.3  320  30 15   8.7   4.8 | -14.8   5.4  330  22 11   7.6   4.2
 11500 -13.0   8.6  320  27 14   8.4   4.6 | -13.7   7.3  330  20 11   7.1   3.9
 11000 -11.8  10.8  325  25 13   8.4   4.6 | -12.7   9.1  330  20 10   7.1   3.9
 10500 -10.6  12.9  325  23 12   7.7   4.2 | -11.7  10.9  330  19 10   6.6   3.6
 10250 -10.0  14.0  325  22 11   7.2   4.0 | -11.2  11.8  330  18  9   6.2   3.4
 10000  -9.5  14.9  325  21 11   8.6   4.7 | -10.7  12.7  330  17  9   7.6   4.2
  9750  -8.8  16.2  325  20 10   9.2   5.1 | -10.1  13.8  330  16  8   7.7   4.2
  9500  -8.1  17.4  330  19 10   8.0   4.4 |  -9.6  14.7  330  15  8   6.4   3.5
  9250  -7.5  18.5  330  18  9   8.4   4.6 |  -9.1  15.6  335  14  7   6.6   3.6
  9000  -6.9  19.6  335  17  9   7.6   4.2 |  -8.6  16.5  335  13  7   6.6   3.6
  8750  -6.4  20.5  335  17  9   7.4   4.1 |  -8.1  17.4  335  12  6   7.5   4.1
  8500  -5.8  21.6  340  15  8   8.2   4.5 |  -7.5  18.5  335  11  6   8.3   4.6
  8250  -5.2  22.6  340  13  7   7.2   4.0 |  -6.9  19.6  335  11  5   7.4   4.1
  8000  -4.6  23.7  345  11  6  10.2   5.6 |  -6.3  20.7  340  10  5  10.3   5.7
  7750  -3.8  25.2  345  10  5  10.9   6.0 |  -5.4  22.3  340  10  5  11.0   6.0
  7500  -3.1  26.4  350  10  5   8.4   4.6 |  -4.8  23.4  340  10  5   8.5   4.7
  7250  -2.4  27.7  350  10  5   9.1   5.0 |  -4.1  24.6  340   9  5   9.4   5.2
  7000  -1.7  28.9  350   9  5  10.8   5.9 |  -3.3  26.1  340   9  5  11.1   6.1
  6750  -0.9  30.4  350   9  5  10.5   5.8 |  -2.5  27.5  340   9  5  10.8   5.9
  6500  -0.2  31.6  350   9  5   8.8   4.8 |  -1.7  28.9  335   9  5   9.3   5.1
  6250   0.5  32.9  350   9  4   9.8   5.4 |  -1.0  30.2  335   9  4  10.5   5.7
  6000   1.3  34.3  350   8  4  10.5   5.7 |  -0.2  31.6  335   8  4  11.2   6.2
  5750   2.1  35.8  350   8  4  10.0   5.5 |   0.6  33.1  335   8  4  10.6   5.8
  5500   2.8  37.0  350   7  4  11.6   6.4 |   1.4  34.5  335   8  4   8.7   4.7
________________________________________________________________________________

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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