Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 230111
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1910 MDT Wednesday, March 22, 2017

This forecast is for Thursday, March 23, 2017:

If the trigger temperature of 69.0 F/20.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 692 ft/min (3.5 m/s)
   Maximum height of thermals.................. 13166 ft MSL (7859 ft AGL)

Forecast maximum temperature................... 72.0 F/22.7 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6960 ft MSL (1654 ft AGL)
Thermal soaring outlook for Friday 03/24....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 34318 ft MSL (29011 ft AGL)
Wave soaring outlook for Friday 03/24.......... Poor

Remarks...

Sunrise/Sunset.................... 06:57:31 / 19:13:52 MDT
Total possible sunshine........... 12 hr 16 min 21 sec (736 min 21 sec)
Altitude of sun at 13:05:52 MDT... 51.57 degrees

Upper air data from numerical model forecast valid on 03/23/2017 at 0600 MDT

Freezing level.................. 12664 ft MSL (7357 ft AGL)
Convective condensation level... 18384 ft MSL (13077 ft AGL)
Lifted condensation level....... 17602 ft MSL (12295 ft AGL)
Lifted index.................... +1.4
K index......................... +10.2

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  -62.0 -79.6   240   58   30   3.7   2.1      M     M       M      M    M
 45000  -56.3 -69.3   235   70   36   1.7   0.9      M     M       M      M    M
 40000  -53.7 -64.7   240   64   33   1.8   1.0      M     M       M      M    M
 38000  -52.3 -62.1   240   69   36   2.6   1.4      M     M       M      M    M
 36000  -50.8 -59.4   235   78   40   2.6   1.4      M     M       M      M    M
 34000  -48.8 -55.8   230   86   44   6.0   3.3      M     M       M      M    M
 32000  -45.3 -49.5   230   85   44   5.9   3.3      M     M       M      M    M
 30000  -41.2 -42.2   225   83   43   6.3   3.4   34.0  93.3     8.9      M    M
 29000  -39.3 -38.7   225   80   41   6.3   3.4   32.6  90.6     7.9      M    M
 28000  -37.4 -35.3   220   78   40   6.3   3.4   31.3  88.3     7.0      M    M
 27000  -35.5 -31.9   220   76   39   8.1   4.4   30.2  86.3     6.2      M    M
 26000  -32.9 -27.2   220   75   39   8.6   4.7   29.6  85.3     5.9      M    M
 25000  -30.3 -22.5   215   74   38   8.6   4.7   29.2  84.5     5.6      M    M
 24000  -27.8 -18.0   215   73   38   8.1   4.5   28.9  84.0     5.4      M    M
 23000  -25.5 -13.9   215   71   37   7.5   4.1   28.0  82.3     4.7      M    M
 22000  -23.3  -9.9   215   69   36   7.5   4.1   27.2  80.9     4.1      M    M
 21000  -21.0  -5.8   215   67   34   7.8   4.3   26.5  79.6     3.5      M    M
 20000  -18.7  -1.7   215   62   32   7.9   4.3   25.7  78.3     2.9      M    M
 19500  -17.5   0.5   215   60   31   7.9   4.3   25.4  77.7     2.6      M    M
 19000  -16.4   2.5   215   57   30   7.9   4.3   25.1  77.2     2.3      M    M
 18500  -15.2   4.6   220   55   28   8.1   4.5   24.8  76.7     2.1      M    M
 18000  -14.0   6.8   215   52   27   8.4   4.6   24.6  76.2     1.9      M    M
 17500  -12.7   9.1   215   49   25   8.4   4.6   24.3  75.8     1.7      M    M
 17000  -11.5  11.3   215   47   24   8.3   4.6   24.1  75.4     1.5      M    M
 16500  -10.2  13.6   215   47   24   8.4   4.6   23.9  74.9     1.2      M    M
 16000   -8.4  16.9   210   47   24   8.7   4.8   23.5  74.4     0.9      M    M
 15500   -7.1  19.2   210   47   24   8.7   4.8   23.4  74.0     0.8      M    M
 15000   -5.8  21.6   210   47   24   8.6   4.7   23.2  73.7     0.6      M    M
 14500   -4.5  23.9   210   47   24   8.6   4.7   23.0  73.4     0.5      M    M
 14000   -3.2  26.2   210   47   24   8.5   4.7   22.8  73.1     0.3      M    M
 13500   -1.9  28.6   215   46   24   8.4   4.6   22.6  72.7     0.1      M    M
 13000   -0.7  30.7   215   45   23   8.5   4.6   22.4  72.3    -0.1    666  3.4
 12500    0.6  33.1   215   45   23   8.5   4.7   22.2  71.9    -0.3    614  3.1
 12000    1.8  35.2   215   45   23   8.4   4.6   22.0  71.5    -0.5    563  2.9
 11500    3.0  37.4   220   45   23   8.3   4.5   21.7  71.1    -0.8    511  2.6
 11000    4.3  39.7   220   45   23   8.2   4.5   21.5  70.7    -1.0    460  2.3
 10500    5.4  41.7   225   44   23   7.8   4.3   21.3  70.3    -1.3    409  2.1
 10250    6.0  42.8   225   44   22   9.0   4.9   21.1  70.0    -1.4    384  2.0
 10000    6.8  44.2   225   44   22  10.0   5.5   21.1  70.0    -1.5    355  1.8
  9750    7.5  45.5   225   41   21   9.1   5.0   21.1  70.0    -1.5    327  1.7
  9500    8.1  46.6   225   37   19   8.9   4.9   21.0  69.9    -1.6    299  1.5
  9250    8.8  47.8   220   33   17   8.9   4.9   21.0  69.8    -1.6    272  1.4
  9000    9.4  48.9   220   29   15   7.4   4.1   20.9  69.6    -1.7    246  1.2
  8750    9.9  49.8   220   28   14   6.6   3.6   20.6  69.1    -1.9    223  1.1
  8500   10.5  50.9   220   29   15   7.3   4.0   20.4  68.8    -2.1    199  1.0
  8250   11.0  51.8   225   29   15   6.3   3.5   20.2  68.4    -2.3    176  0.9
  8000   11.6  52.9   225   30   15   9.6   5.3   20.0  68.0    -2.5    152  0.8
  7750   12.4  54.3   230   29   15  10.0   5.5   20.1  68.2    -2.4    119  0.6
  7500   13.0  55.4   230   28   15   7.0   3.8   19.9  67.9    -2.6     95  0.5
  7250   13.5  56.3   230   28   14   7.8   4.3   19.8  67.6    -2.8     71  0.4
  7000   14.1  57.4   235   28   14   7.9   4.3   19.6  67.3    -2.9     46  0.2
  6750   14.6  58.3   235   28   14   4.6   2.5   19.4  66.9    -3.2     24  0.1
  6500   14.8  58.6   235   28   14   5.1   2.8   18.9  66.1    -3.7     10  0.0
  6250   15.1  59.2   235   27   14  -3.0  -1.7   18.5  65.3    -4.2      M    M
  6000   14.2  57.6   235   25   13 -16.3  -8.9   16.9  62.4    -5.8     15  0.1
  5750   12.7  54.9   230   21   11 -21.7 -11.9   14.8  58.6    -8.0     51  0.3
  5500   10.7  51.3   220   14    7 -31.3 -17.2   12.0  53.7   -10.8    105  0.5

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

           03/23/2017 at 0900 MDT          |       03/23/2017 at 1200 MDT
                                           |
K index... -16.0  LI... +3.2               | K index... -13.6  LI... +4.4
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -60.3 -76.5  235  54 28   3.7   2.0 | -58.2 -72.8  235  48 25   3.9   2.1
 45000 -54.7 -66.5  235  61 31   1.2   0.7 | -52.4 -62.3  230  48 25   0.4   0.2
 40000 -52.6 -62.7  235  55 28   1.4   0.8 | -51.1 -60.0  225  57 29   0.8   0.5
 38000 -51.7 -61.1  230  63 33   1.3   0.7 | -50.7 -59.3  220  65 33   0.7   0.4
 36000 -50.9 -59.6  225  80 41   1.3   0.7 | -50.3 -58.5  220  78 40   0.7   0.4
 34000 -49.7 -57.5  225  94 48   6.0   3.3 | -49.6 -57.3  220  89 46   4.8   2.7
 32000 -46.4 -51.5  220  93 48   5.6   3.1 | -46.6 -51.9  215  93 48   5.0   2.7
 30000 -42.4 -44.3  220  90 46   6.7   3.7 | -43.1 -45.6  210  95 49   6.6   3.6
 29000 -40.4 -40.7  215  87 45   6.8   3.7 | -41.1 -42.0  210  92 47   6.6   3.6
 28000 -38.3 -36.9  215  84 43   6.8   3.7 | -39.1 -38.4  210  89 46   6.6   3.6
 27000 -36.3 -33.3  210  80 41   7.7   4.2 | -37.1 -34.8  205  87 45   7.0   3.8
 26000 -33.8 -28.8  210  79 40   8.4   4.6 | -34.8 -30.6  205  85 44   8.0   4.4
 25000 -31.3 -24.3  210  77 39   8.4   4.6 | -32.4 -26.3  205  83 43   8.0   4.4
 24000 -28.7 -19.7  210  75 39   8.4   4.6 | -30.0 -22.0  205  81 42   8.0   4.4
 23000 -26.3 -15.3  210  72 37   8.1   4.4 | -27.4 -17.3  205  78 40   8.8   4.9
 22000 -23.9 -11.0  210  69 36   8.1   4.4 | -24.7 -12.5  205  76 39   8.8   4.9
 21000 -21.5  -6.7  210  66 34   8.2   4.5 | -22.1  -7.8  205  73 38   8.8   4.8
 20000 -19.0  -2.2  210  63 32   8.3   4.5 | -19.5  -3.1  205  68 35   8.7   4.7
 19500 -17.8  -0.0  210  62 32   8.3   4.5 | -18.2  -0.8  205  65 34   8.7   4.7
 19000 -16.5   2.3  210  60 31   8.3   4.5 | -16.9   1.6  205  62 32   8.6   4.7
 18500 -15.3   4.5  215  59 30   8.3   4.6 | -15.6   3.9  205  60 31   8.5   4.7
 18000 -14.0   6.8  215  57 29   8.3   4.6 | -14.5   5.9  205  59 31   7.0   3.8
 17500 -12.8   9.0  215  55 28   8.3   4.6 | -13.4   7.9  210  61 31   7.1   3.9
 17000 -11.5  11.3  215  53 27   8.7   4.8 | -12.3   9.9  215  61 32   7.2   4.0
 16500 -10.2  13.6  215  51 26   8.7   4.7 | -11.2  11.8  215  59 31   7.3   4.0
 16000  -8.4  16.9  215  48 25   7.1   3.9 |  -9.6  14.7  215  57 29   7.6   4.2
 15500  -7.3  18.9  210  46 24   7.3   4.0 |  -8.4  16.9  220  56 29   7.6   4.2
 15000  -6.2  20.8  210  44 23   7.4   4.1 |  -7.3  18.9  220  55 28   7.1   3.9
 14500  -5.0  23.0  215  45 23   7.4   4.1 |  -6.3  20.7  220  53 28   6.6   3.6
 14000  -3.9  25.0  215  45 23   7.3   4.0 |  -5.3  22.5  220  52 27   7.1   3.9
 13500  -2.9  26.8  215  45 23   7.1   3.9 |  -4.1  24.6  220  48 25   8.6   4.7
 13000  -1.8  28.8  215  46 23   6.9   3.8 |  -2.8  27.0  220  44 23   8.6   4.7
 12500  -0.9  30.4  220  45 23   6.0   3.3 |  -1.6  29.1  220  39 20   8.5   4.7
 12000  -0.0  32.0  220  44 23   6.4   3.5 |  -0.3  31.5  220  34 17   8.5   4.7
 11500   1.1  34.0  225  43 22   8.4   4.6 |   0.9  33.6  225  31 16   6.9   3.8
 11000   2.2  36.0  225  41 21   8.3   4.6 |   1.9  35.4  230  30 16   7.2   3.9
 10500   3.4  38.1  225  40 21   8.3   4.6 |   2.8  37.0  235  29 15   6.0   3.3
 10250   4.0  39.2  225  39 20   8.1   4.5 |   3.2  37.8  240  27 14   6.1   3.3
 10000   4.6  40.3  230  39 20   8.3   4.5 |   3.6  38.5  240  25 13   5.7   3.1
  9750   5.3  41.5  230  38 19   9.5   5.2 |   4.0  39.2  240  23 12   8.8   4.8
  9500   6.0  42.8  230  34 18  10.0   5.5 |   4.8  40.6  240  22 11  11.2   6.1
  9250   6.7  44.1  230  31 16  10.0   5.5 |   5.6  42.1  240  21 11  10.5   5.8
  9000   7.4  45.3  230  28 14   8.2   4.5 |   6.3  43.3  240  20 10   8.0   4.4
  8750   7.9  46.2  230  26 13   7.0   3.8 |   6.9  44.4  240  20 10   8.9   4.9
  8500   8.4  47.1  235  26 13   7.7   4.2 |   7.7  45.9  240  19 10  11.2   6.2
  8250   9.0  48.2  235  26 13   7.5   4.1 |   8.5  47.3  240  19 10  11.3   6.2
  8000   9.5  49.1  235  26 13   7.7   4.2 |   9.3  48.7  235  19 10   8.7   4.7
  7750  10.1  50.2  240  27 14   6.8   3.7 |   9.8  49.6  235  19 10   8.1   4.4
  7500  10.5  50.9  240  28 14   6.0   3.3 |  10.6  51.1  235  19 10  10.5   5.8
  7250  11.0  51.8  240  29 15   6.2   3.4 |  11.3  52.3  235  18  9   9.9   5.4
  7000  11.5  52.7  245  29 15   7.9   4.3 |  12.1  53.8  235  18  9   9.9   5.4
  6750  12.1  53.8  245  29 15   7.1   3.9 |  12.8  55.0  235  18  9   9.8   5.4
  6500  12.6  54.7  245  27 14   6.6   3.6 |  13.6  56.5  235  18  9   9.7   5.3
  6250  13.0  55.4  245  26 13   3.1   1.7 |  14.3  57.7  235  17  9  10.3   5.6
  6000  12.9  55.2  240  22 11  -4.2  -2.3 |  15.1  59.2  235  17  9  11.0   6.0
  5750  12.6  54.7  235  17  9  -4.3  -2.3 |  16.0  60.8  235  16  8  16.6   9.1
  5500  12.4  54.3  230  11  6   2.1   1.2 |  17.7  63.9  235  15  8  25.9  14.2

           03/23/2017 at 1500 MDT          |       03/23/2017 at 1800 MDT
                                           |
K index... -3.6  LI... +2.3                | K index... +11.8  LI... +0.8
CAPE... 0.0  CIN... 0.0                    | CAPE... +0.4  CIN... -0.2
                                           |
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 -55.5 -67.9  245  51 26   3.4   1.8 | -55.6 -68.1  250  45 23   3.5   1.9
 45000 -50.4 -58.7  250  56 29   0.6   0.4 | -50.1 -58.2  250  52 27   1.9   1.0
 40000 -49.4 -56.9  220  57 29   0.7   0.4 | -47.7 -53.9  220  51 26   1.6   0.9
 38000 -49.2 -56.6  215  64 33  -0.2  -0.1 | -47.3 -53.1  210  53 27  -0.8  -0.4
 36000 -49.3 -56.7  215  74 38  -0.2  -0.1 | -47.8 -54.0  210  54 28  -0.8  -0.4
 34000 -49.4 -56.9  215  83 43   1.6   0.9 | -48.2 -54.8  210  55 28   0.1   0.0
 32000 -47.6 -53.7  210  86 44   2.9   1.6 | -46.9 -52.4  205  63 33   2.4   1.3
 30000 -45.3 -49.5  210  88 45   7.9   4.3 | -45.1 -49.2  205  73 37   5.2   2.8
 29000 -43.0 -45.4  205  87 45   7.4   4.1 | -43.4 -46.1  205  71 37   5.6   3.1
 28000 -40.8 -41.4  205  86 44   7.4   4.1 | -41.8 -43.2  205  70 36   5.6   3.1
 27000 -38.6 -37.5  205  85 44   7.4   4.1 | -40.1 -40.2  205  68 35   5.5   3.0
 26000 -36.2 -33.2  205  82 42   8.3   4.5 | -38.0 -36.4  210  65 34   7.6   4.2
 25000 -33.7 -28.7  200  79 41   8.3   4.5 | -35.7 -32.3  210  62 32   7.6   4.2
 24000 -31.2 -24.2  200  76 39   8.3   4.5 | -33.5 -28.3  210  58 30   7.6   4.2
 23000 -28.7 -19.7  200  73 37   8.4   4.6 | -31.1 -24.0  210  54 28   8.3   4.6
 22000 -26.2 -15.2  205  69 35   8.4   4.6 | -28.6 -19.5  210  50 26   8.4   4.6
 21000 -23.7 -10.7  205  65 33   8.3   4.6 | -26.1 -15.0  210  45 23   8.4   4.6
 20000 -21.3  -6.3  210  62 32   8.0   4.4 | -23.6 -10.5  205  41 21   8.6   4.7
 19500 -20.1  -4.2  210  61 31   8.0   4.4 | -22.3  -8.1  205  40 20   8.6   4.7
 19000 -18.9  -2.0  210  59 31   8.0   4.4 | -21.0  -5.8  205  38 20   8.6   4.7
 18500 -17.7   0.1  210  58 30   8.1   4.4 | -19.7  -3.5  200  37 19   8.7   4.7
 18000 -16.6   2.1  210  57 29   7.3   4.0 | -18.5  -1.3  200  35 18   8.1   4.4
 17500 -15.5   4.1  215  57 30   7.3   4.0 | -17.3   0.9  200  34 18   8.1   4.4
 17000 -14.4   6.1  215  57 29   7.6   4.2 | -16.1   3.0  200  33 17   8.3   4.5
 16500 -13.2   8.2  215  53 27   7.8   4.3 | -14.8   5.4  200  33 17   8.5   4.7
 16000 -11.4  11.5  210  47 24   7.3   4.0 | -13.5   7.7  200  32 16   8.5   4.7
 15500 -10.4  13.3  215  43 22   7.2   4.0 | -11.6  11.1  200  31 16   8.8   4.8
 15000  -9.3  15.3  215  39 20   7.4   4.1 | -10.3  13.5  200  30 15   8.8   4.8
 14500  -8.2  17.2  215  35 18   7.8   4.3 |  -9.0  15.8  200  29 15   8.6   4.7
 14000  -7.0  19.4  215  32 16   8.1   4.4 |  -7.7  18.1  200  28 14   8.6   4.7
 13500  -5.8  21.6  215  28 15   9.1   5.0 |  -6.4  20.5  200  27 14   9.2   5.1
 13000  -4.5  23.9  210  25 13   9.1   5.0 |  -5.0  23.0  200  26 13   9.2   5.0
 12500  -3.1  26.4  210  23 12   9.5   5.2 |  -3.6  25.5  200  25 13   9.4   5.1
 12000  -1.7  28.9  205  20 10   9.5   5.2 |  -2.3  27.9  200  24 12   9.4   5.1
 11500  -0.3  31.5  205  19 10   9.7   5.3 |  -0.9  30.4  205  23 12   9.3   5.1
 11000   1.1  34.0  205  18  9   9.6   5.3 |   0.5  32.9  205  23 12   9.3   5.1
 10500   2.6  36.7  205  18  9  10.1   5.5 |   2.0  35.6  210  22 11  10.3   5.6
 10250   3.4  38.1  205  18  9  10.0   5.5 |   2.7  36.9  210  22 11   9.5   5.2
 10000   4.1  39.4  205  17  9   9.8   5.4 |   3.4  38.1  210  22 11   8.1   4.4
  9750   4.8  40.6  205  17  9  10.3   5.6 |   4.0  39.2  210  22 11   9.5   5.2
  9500   5.6  42.1  205  17  9  10.8   5.9 |   4.8  40.6  215  21 11  11.1   6.1
  9250   6.4  43.5  205  17  9  10.5   5.8 |   5.6  42.1  215  21 11  10.9   6.0
  9000   7.2  45.0  205  17  9   8.3   4.5 |   6.4  43.5  215  21 11   8.8   4.8
  8750   7.8  46.0  205  17  9   9.3   5.1 |   7.0  44.6  215  21 11   9.3   5.1
  8500   8.6  47.5  205  17  9  11.3   6.2 |   7.8  46.0  220  21 11  10.9   6.0
  8250   9.4  48.9  205  17  9  11.4   6.2 |   8.6  47.5  220  21 11  11.2   6.2
  8000  10.2  50.4  205  16  8   9.2   5.0 |   9.4  48.9  220  20 11   8.3   4.6
  7750  10.8  51.4  205  16  8   8.5   4.6 |   9.9  49.8  220  20 10   7.8   4.3
  7500  11.6  52.9  205  16  8  10.3   5.6 |  10.6  51.1  220  20 10  10.4   5.7
  7250  12.3  54.1  205  16  8   9.8   5.4 |  11.4  52.5  220  20 10   9.8   5.4
  7000  13.0  55.4  205  16  8   9.8   5.4 |  12.1  53.8  220  20 10   9.6   5.3
  6750  13.8  56.8  205  16  8  10.0   5.5 |  12.8  55.0  220  20 10   9.6   5.3
  6500  14.5  58.1  210  16  8  10.4   5.7 |  13.6  56.5  220  19 10  10.0   5.5
  6250  15.3  59.5  210  15  8  10.4   5.7 |  14.3  57.7  225  19 10  10.0   5.5
  6000  16.1  61.0  210  15  8   9.9   5.4 |  15.0  59.0  225  19 10   9.7   5.3
  5750  17.0  62.6  210  14  7  16.0   8.8 |  15.8  60.4  225  17  9  11.7   6.4
  5500  18.6  65.5  210  13  7  27.5  15.1 |  16.8  62.2  225  15  8  15.7   8.6
________________________________________________________________________________

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.

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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