Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 230018
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1718 MST Monday, December 22, 2014

This forecast is for Tuesday, December 23, 2014:

If the trigger temperature of 43.8 F/6.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5885 ft MSL (598 ft AGL)

Forecast maximum temperature................... 36.0 F/2.7 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. None
Thermal soaring outlook for Wednesday 12/24.... Fair

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1700 MST)......... No change.
Height of stable layer (12-18K ft MSL)......... 17073 ft MSL (11786 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 33524 ft MSL (28237 ft AGL)
Wave soaring outlook for Wednesday 12/24....... Fair

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.................. 6616 ft MSL (1329 ft AGL)
Convective condensation level... 10900 ft MSL (5613 ft AGL)
Lifted condensation level....... 9083 ft MSL (3796 ft AGL)
Lifted index.................... +9.3
K index......................... +13.6

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  -54.1 -65.4   315   40   21   2.9   1.6      M     M       M      M    M
 45000  -49.8 -57.6   310   51   26   2.9   1.6      M     M       M      M    M
 40000  -47.3 -53.1   330   68   35   1.4   0.8      M     M       M      M    M
 38000  -46.7 -52.1   330   77   40  -0.6  -0.3      M     M       M      M    M
 36000  -47.1 -52.8   330   88   45  -0.6  -0.3      M     M       M      M    M
 34000  -47.5 -53.5   330   99   51  -0.6  -0.3      M     M       M      M    M
 32000  -46.5 -51.7   330  101   52   2.3   1.3      M     M       M      M    M
 30000  -45.1 -49.2   330  101   52   2.4   1.3      M     M       M      M    M
 29000  -44.1 -47.4   330  100   51   4.4   2.4      M     M       M      M    M
 28000  -42.7 -44.9   330   99   51   4.5   2.5      M     M       M      M    M
 27000  -41.0 -41.8   330   97   50   4.5   2.5      M     M       M      M    M
 26000  -39.6 -39.3   330   96   49   6.1   3.3   24.4  75.9    17.4      M    M
 25000  -37.8 -36.0   330   93   48   6.0   3.3   22.9  73.1    16.4      M    M
 24000  -36.0 -32.8   330   90   46   6.0   3.3   21.5  70.6    15.5      M    M
 23000  -34.3 -29.7   330   87   45   5.0   2.8   20.1  68.1    14.5      M    M
 22000  -32.8 -27.0   325   81   42   5.1   2.8   18.3  64.9    13.2      M    M
 21000  -31.3 -24.3   325   76   39   5.1   2.8   16.6  61.9    12.0      M    M
 20000  -29.6 -21.3   320   71   36   6.7   3.7   15.2  59.4    10.9      M    M
 19500  -28.6 -19.5   320   68   35   6.7   3.7   14.7  58.4    10.5      M    M
 19000  -27.6 -17.7   320   66   34   6.7   3.7   14.1  57.4    10.1      M    M
 18500  -26.6 -15.9   320   64   33   6.6   3.6   13.6  56.5     9.7      M    M
 18000  -25.6 -14.1   315   62   32   5.7   3.1   13.1  55.7     9.4      M    M
 17500  -25.0 -13.0   315   61   31   2.9   1.6   12.1  53.8     8.5      M    M
 17000  -24.6 -12.3   315   59   31   2.5   1.4   10.9  51.7     7.5      M    M
 16500  -23.8 -10.8   315   57   29   8.2   4.5   10.2  50.3     6.9      M    M
 16000  -22.6  -8.7   315   54   28   7.9   4.4    9.9  49.7     6.6      M    M
 15500  -21.5  -6.7   315   52   27   7.8   4.3    9.6  49.2     6.4      M    M
 15000  -20.3  -4.5   315   53   27   7.8   4.3    9.2  48.6     6.1      M    M
 14500  -19.2  -2.6   320   53   27   7.5   4.1    8.9  48.0     5.8      M    M
 14000  -17.6   0.3   320   50   26   7.0   3.8    8.2  46.8     5.3      M    M
 13500  -16.5   2.3   320   49   25   8.2   4.5    7.9  46.1     4.9      M    M
 13000  -15.3   4.5   320   47   24   8.2   4.5    7.6  45.7     4.7      M    M
 12500  -14.1   6.6   325   45   23   8.7   4.8    7.4  45.3     4.5      M    M
 12000  -12.8   9.0   325   43   22   8.7   4.8    7.2  45.0     4.4      M    M
 11500  -11.5  11.3   325   41   21   9.6   5.3    7.1  44.8     4.3      M    M
 11000  -10.0  14.0   325   40   20   9.8   5.4    7.1  44.8     4.2      M    M
 10500   -8.6  16.5   330   38   20   8.8   4.8    7.0  44.7     4.2      M    M
 10250   -8.0  17.6   330   37   19   8.3   4.6    7.0  44.5     4.1      M    M
 10000   -7.4  18.7   330   36   18  10.1   5.6    6.9  44.4     4.0      M    M
  9750   -6.5  20.3   330   34   18  10.7   5.9    7.0  44.6     4.2      M    M
  9500   -5.8  21.6   330   33   17   9.2   5.0    7.0  44.5     4.1      M    M
  9250   -5.1  22.8   330   32   16   9.8   5.4    6.9  44.5     4.1      M    M
  9000   -4.4  24.1   330   31   16   8.6   4.7    6.9  44.5     4.1      M    M
  8750   -3.8  25.2   330   30   15   7.7   4.2    6.8  44.2     4.0      M    M
  8500   -3.2  26.2   330   28   15   8.3   4.5    6.6  44.0     3.9      M    M
  8250   -2.6  27.3   330   27   14   8.0   4.4    6.5  43.7     3.7      M    M
  8000   -2.0  28.4   330   26   13   8.6   4.7    6.4  43.5     3.6      M    M
  7750   -1.4  29.5   330   24   12   5.9   3.2    6.3  43.3     3.5      M    M
  7500   -1.2  29.8   335   22   11   3.4   1.9    5.8  42.5     3.1      M    M
  7250   -0.9  30.4   335   20   10   4.1   2.2    5.4  41.7     2.6      M    M
  7000   -0.6  30.9   335   17    9   4.6   2.5    4.9  40.9     2.2      M    M
  6750   -0.2  31.6   340   15    8   5.1   2.8    4.6  40.3     1.8      M    M
  6500    0.1  32.2   340   12    6   5.7   3.1    4.2  39.6     1.5      M    M
  6250    0.5  32.9   340    9    5   3.2   1.8    3.9  39.0     1.1      M    M
  6000    0.5  32.9   340    7    4  -0.4  -0.2    3.2  37.8     0.4      M    M
  5750    0.5  32.9   335    5    3   0.9   0.5    2.5  36.5    -0.3      M    M
  5500    0.6  33.1   310    2    1   2.2   1.2    1.9  35.4    -1.0      M    M

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

           12/22/2014 at 0800 MST          |       12/22/2014 at 1100 MST
                                           |
K index... +11.0  LI... +2.2               | K index... +14.2  LI... +0.1
CAPE... +16.5  CIN... -59.0                | CAPE... +0.2  CIN... -49.5
                                           |
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 -53.6 -64.5  310  30 15   2.8   1.5 | -52.5 -62.5  315  24 12   2.4   1.3
 45000 -49.5 -57.1  310  32 16   2.8   1.5 | -48.9 -56.0  315  29 15   2.4   1.3
 40000 -46.9 -52.4  325  56 29   1.5   0.8 | -44.8 -48.6  330  57 29   2.6   1.4
 38000 -46.1 -51.0  330  67 34   0.5   0.3 | -43.5 -46.3  330  67 35  -0.0  -0.0
 36000 -45.8 -50.4  330  76 39   0.5   0.3 | -43.4 -46.1  330  71 36   0.2   0.1
 34000 -45.5 -49.9  330  86 44   0.5   0.3 | -43.3 -45.9  330  74 38   0.2   0.1
 32000 -45.1 -49.2  330  88 45   0.7   0.4 | -44.1 -47.4  325  76 39  -2.2  -1.2
 30000 -44.7 -48.5  330  87 45   0.7   0.4 | -45.4 -49.7  325  76 39  -2.2  -1.2
 29000 -44.2 -47.6  325  86 44   3.1   1.7 | -45.8 -50.4  325  75 39   2.3   1.3
 28000 -43.3 -45.9  325  85 44   3.0   1.7 | -45.2 -49.4  325  72 37   1.8   1.0
 27000 -42.2 -44.0  325  84 43   3.0   1.7 | -44.5 -48.1  320  68 35   1.8   1.0
 26000 -41.3 -42.3  325  83 43   4.2   2.3 | -43.9 -47.0  320  65 33   4.1   2.2
 25000 -40.0 -40.0  330  81 42   4.2   2.3 | -42.4 -44.3  320  64 33   5.2   2.9
 24000 -38.7 -37.7  330  79 41   4.2   2.3 | -40.8 -41.4  320  63 33   5.3   2.9
 23000 -37.4 -35.3  330  77 39   6.1   3.4 | -39.2 -38.6  320  62 32   6.1   3.4
 22000 -35.4 -31.7  325  73 38   6.5   3.6 | -37.2 -35.0  315  58 30   6.7   3.7
 21000 -33.5 -28.3  325  70 36   6.6   3.6 | -35.2 -31.4  315  53 27   6.7   3.7
 20000 -31.4 -24.5  320  66 34   7.9   4.3 | -33.1 -27.6  315  48 25   7.5   4.1
 19500 -30.2 -22.4  320  64 33   7.9   4.3 | -32.0 -25.6  315  47 24   7.4   4.1
 19000 -29.1 -20.4  320  62 32   7.9   4.3 | -30.9 -23.6  315  45 23   7.4   4.1
 18500 -27.9 -18.2  320  59 31   7.8   4.3 | -29.8 -21.6  315  43 22   7.4   4.1
 18000 -26.7 -16.1  320  57 29   7.2   4.0 | -28.7 -19.7  315  42 21   7.5   4.1
 17500 -26.0 -14.8  320  56 29   4.2   2.3 | -27.5 -17.5  315  41 21   8.4   4.6
 17000 -25.3 -13.5  325  56 29   4.4   2.4 | -26.3 -15.3  315  40 21   8.4   4.6
 16500 -24.6 -12.3  325  55 28   4.7   2.6 | -25.1 -13.2  315  40 20   7.6   4.2
 16000 -23.9 -11.0  325  53 27   4.7   2.6 | -24.0 -11.2  315  40 21   7.6   4.2
 15500 -23.2  -9.8  325  50 26   7.1   3.9 | -22.8  -9.0  315  41 21   8.0   4.4
 15000 -21.9  -7.4  325  47 24   8.2   4.5 | -21.6  -6.9  315  40 21   8.3   4.6
 14500 -20.7  -5.3  325  44 23   8.3   4.6 | -20.4  -4.7  320  40 21   8.4   4.6
 14000 -18.8  -1.8  325  42 22   8.4   4.6 | -18.5  -1.3  315  36 19   8.5   4.6
 13500 -17.6   0.3  325  41 21   8.7   4.8 | -17.2   1.0  315  34 18   8.4   4.6
 13000 -16.3   2.7  325  39 20   8.8   4.8 | -16.0   3.2  320  33 17   8.4   4.6
 12500 -15.0   5.0  325  37 19   8.4   4.6 | -14.8   5.4  320  32 16   7.8   4.3
 12000 -13.8   7.2  325  35 18   8.2   4.5 | -13.7   7.3  320  27 14   7.5   4.1
 11500 -12.5   9.5  325  34 17   9.5   5.2 | -12.5   9.5  315  22 11   8.7   4.8
 11000 -11.1  12.0  325  33 17   9.7   5.3 | -11.2  11.8  320  19 10   9.1   5.0
 10500  -9.7  14.5  330  32 17   8.7   4.8 |  -9.9  14.2  325  16  8   8.3   4.5
 10250  -9.1  15.6  330  32 16   8.1   4.5 |  -9.3  15.3  325  14  7   7.6   4.2
 10000  -8.4  16.9  330  31 16   9.9   5.4 |  -8.7  16.3  325  13  7   9.2   5.1
  9750  -7.6  18.3  330  31 16  10.5   5.8 |  -7.9  17.8  325  11  6   9.8   5.4
  9500  -6.9  19.6  330  30 16   9.2   5.0 |  -7.3  18.9  325  10  5   8.2   4.5
  9250  -6.2  20.8  330  29 15   9.5   5.2 |  -6.7  19.9  325   9  4   8.6   4.7
  9000  -5.5  22.1  330  29 15   9.4   5.1 |  -6.1  21.0  325   7  4   7.2   4.0
  8750  -4.9  23.2  330  28 14   8.8   4.8 |  -5.6  21.9  320   7  3   7.3   4.0
  8500  -4.2  24.4  330  27 14   8.5   4.7 |  -4.9  23.2  315   6  3   8.8   4.8
  8250  -3.6  25.5  330  26 13   8.4   4.6 |  -4.3  24.3  310   5  2   8.1   4.4
  8000  -3.0  26.6  330  25 13   9.1   5.0 |  -3.7  25.3  305   4  2   9.6   5.3
  7750  -2.3  27.9  330  23 12   7.8   4.3 |  -3.0  26.6  280   3  1   8.4   4.6
  7500  -1.8  28.8  330  21 11   6.1   3.3 |  -2.5  27.5  255   2  1   6.1   3.3
  7250  -1.4  29.5  330  19 10   6.5   3.6 |  -2.0  28.4  215   2  1   6.7   3.7
  7000  -0.9  30.4  330  17  9   7.0   3.8 |  -1.6  29.1  190   3  2   6.4   3.5
  6750  -0.4  31.3  330  15  7   5.9   3.2 |  -1.1  30.0  160   3  2   5.7   3.2
  6500  -0.1  31.8  325  12  6   5.0   2.7 |  -0.8  30.6  140   4  2   5.1   2.8
  6250   0.3  32.5  325  10  5   4.1   2.3 |  -0.4  31.3  130   5  3   6.0   3.3
  6000   0.5  32.9  310   7  4   3.0   1.6 |   0.1  32.2  125   5  3   7.0   3.8
  5750   0.6  33.1  285   6  3   0.8   0.4 |   0.6  33.1  120   5  3   8.3   4.5
  5500   0.4  32.7  250   6  3  -6.3  -3.4 |   1.3  34.3  125   4  2  11.3   6.2

           12/22/2014 at 1400 MST          |       12/22/2014 at 1700 MST
                                           |
K index... +19.6  LI... -0.6               | K index... +13.4  LI... -0.9
CAPE... +76.3  CIN... -0.4                 | CAPE... +123.9  CIN... -8.9
                                           |
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 -51.7 -61.1  305  29 15   3.3   1.8 | -51.6 -60.9  315  27 14   2.9   1.6
 45000 -46.7 -52.1  305  34 18   3.3   1.8 | -47.3 -53.1  325  28 15   2.9   1.6
 40000 -42.7 -44.9  330  51 27   2.5   1.4 | -42.6 -44.7  335  50 26   3.0   1.7
 38000 -41.5 -42.7  335  60 31  -1.2  -0.6 | -41.1 -42.0  335  59 30  -1.6  -0.9
 36000 -42.0 -43.6  335  65 34  -0.8  -0.4 | -41.7 -43.1  335  64 33  -1.1  -0.6
 34000 -42.4 -44.3  335  71 37  -0.8  -0.4 | -42.4 -44.3  340  69 36  -1.1  -0.6
 32000 -43.3 -45.9  335  72 37  -1.9  -1.0 | -43.3 -45.9  335  70 36  -1.7  -0.9
 30000 -44.4 -47.9  335  69 36  -1.9  -1.0 | -44.3 -47.7  335  69 35  -1.7  -1.0
 29000 -44.9 -48.8  335  67 35  -0.6  -0.4 | -44.7 -48.5  330  67 34   0.4   0.2
 28000 -45.1 -49.2  330  63 33  -0.4  -0.2 | -44.6 -48.3  330  63 32   0.3   0.2
 27000 -45.2 -49.4  330  60 31  -0.4  -0.2 | -44.5 -48.1  330  59 31   0.3   0.2
 26000 -45.3 -49.5  325  57 29   1.5   0.8 | -44.4 -47.9  325  56 29   0.9   0.5
 25000 -44.1 -47.4  325  54 28   4.5   2.5 | -43.9 -47.0  325  55 28   2.0   1.1
 24000 -42.7 -44.9  320  51 26   4.5   2.5 | -43.3 -45.9  320  54 28   2.0   1.1
 23000 -41.4 -42.5  320  47 24   5.9   3.2 | -42.7 -44.9  315  54 28   4.2   2.3
 22000 -39.1 -38.4  320  47 24   7.7   4.2 | -40.3 -40.5  315  52 27   8.5   4.6
 21000 -36.8 -34.2  320  46 24   7.7   4.2 | -37.8 -36.0  315  50 26   8.5   4.6
 20000 -34.4 -29.9  320  45 23   9.1   5.0 | -35.2 -31.4  315  48 25   8.5   4.7
 19500 -33.0 -27.4  320  45 23   9.0   4.9 | -34.0 -29.2  315  48 25   8.5   4.7
 19000 -31.7 -25.1  320  44 23   9.0   4.9 | -32.7 -26.9  320  48 25   8.5   4.7
 18500 -30.4 -22.7  320  43 22   9.0   4.9 | -31.4 -24.5  320  48 25   8.5   4.7
 18000 -29.0 -20.2  320  43 22   9.0   5.0 | -30.1 -22.2  325  48 25   8.6   4.7
 17500 -27.7 -17.9  320  42 22   8.7   4.8 | -28.9 -20.0  325  48 25   8.1   4.4
 17000 -26.4 -15.5  320  41 21   8.7   4.8 | -27.7 -17.9  330  48 25   8.1   4.5
 16500 -25.1 -13.2  320  39 20   8.6   4.7 | -26.5 -15.7  330  48 25   8.4   4.6
 16000 -23.9 -11.0  320  37 19   8.5   4.7 | -25.2 -13.4  330  48 25   8.4   4.6
 15500 -22.6  -8.7  325  35 18   8.5   4.7 | -23.9 -11.0  335  48 25   8.3   4.5
 15000 -21.3  -6.3  325  33 17   8.5   4.6 | -22.7  -8.9  335  48 25   8.1   4.4
 14500 -19.5  -3.1  325  29 15   8.5   4.6 | -21.0  -5.8  335  47 24   7.6   4.1
 14000 -18.2  -0.8  325  26 13   8.5   4.7 | -19.9  -3.8  340  46 24   7.5   4.1
 13500 -17.0   1.4  325  23 12   7.6   4.2 | -18.7  -1.7  340  45 23   7.9   4.3
 13000 -15.9   3.4  325  21 11   7.2   4.0 | -17.6   0.3  340  43 22   8.0   4.4
 12500 -14.9   5.2  330  18 10   7.4   4.1 | -16.3   2.7  335  40 21   8.9   4.9
 12000 -13.8   7.2  325  16  8   7.6   4.1 | -15.0   5.0  335  38 20   9.3   5.1
 11500 -12.7   9.1  320  13  7   7.2   3.9 | -13.6   7.5  335  36 19   9.1   5.0
 11000 -11.6  11.1  325  13  6   7.0   3.8 | -12.3   9.9  335  35 18   9.1   5.0
 10500 -10.6  12.9  330  12  6   6.5   3.6 | -11.0  12.2  335  33 17   8.0   4.4
 10250 -10.2  13.6  330  11  6   5.9   3.2 | -10.5  13.1  335  32 16   7.5   4.1
 10000  -9.7  14.5  330  10  5   7.1   3.9 |  -9.9  14.2  335  30 16   8.2   4.5
  9750  -9.2  15.4  335  10  5   8.1   4.4 |  -9.3  15.3  340  30 15   8.3   4.6
  9500  -8.6  16.5  335  10  5   7.1   3.9 |  -8.7  16.3  340  28 15   7.6   4.2
  9250  -8.1  17.4  335   8  4   7.3   4.0 |  -8.1  17.4  340  27 14   7.6   4.2
  9000  -7.6  18.3  335   7  4   6.2   3.4 |  -7.6  18.3  340  26 13   7.7   4.2
  8750  -7.2  19.0  335   7  4   5.9   3.2 |  -7.0  19.4  340  25 13   7.1   3.9
  8500  -6.7  19.9  340   6  3   7.2   3.9 |  -6.5  20.3  340  23 12   6.7   3.7
  8250  -6.2  20.8  350   6  3   6.6   3.6 |  -6.1  21.0  340  21 11   6.3   3.5
  8000  -5.7  21.7  355   6  3   8.2   4.5 |  -5.6  21.9  340  20 10   8.2   4.5
  7750  -5.0  23.0  005   5  3   8.6   4.7 |  -4.9  23.2  335  17  9   8.0   4.4
  7500  -4.5  23.9  010   5  3   7.2   4.0 |  -4.5  23.9  335  16  8   5.9   3.2
  7250  -3.9  25.0  020   6  3   7.7   4.2 |  -4.0  24.8  335  14  7   6.5   3.6
  7000  -3.4  25.9  025   6  3   7.1   3.9 |  -3.6  25.5  335  12  6   6.3   3.5
  6750  -2.9  26.8  025   6  3   7.6   4.2 |  -3.1  26.4  325  11  5   6.8   3.7
  6500  -2.3  27.9  025   7  3   8.3   4.6 |  -2.6  27.3  320   9  5   6.9   3.8
  6250  -1.7  28.9  025   7  4   8.3   4.6 |  -2.1  28.2  305   7  4   7.5   4.1
  6000  -1.1  30.0  025   7  4   8.9   4.9 |  -1.6  29.1  300   6  3   8.0   4.4
  5750  -0.4  31.3  025   7  3   9.0   4.9 |  -1.0  30.2  290   5  3   9.2   5.1
  5500   0.3  32.5  025   6  3  11.7   6.4 |  -0.2  31.6  280   4  2  11.9   6.5
________________________________________________________________________________

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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