Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 250028
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1828 MDT Sunday, September 24, 2017

This forecast is for Monday, September 25, 2017:

If the trigger temperature of 53.1 F/11.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 9647 ft MSL (4340 ft AGL)

Forecast maximum temperature................... 54.0 F/12.7 C
Time of trigger temperature.................... 1430 MDT
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................. 6756 ft MSL (1449 ft AGL)
Thermal soaring outlook for Tuesday 09/26...... Poor

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 11951 ft MSL (6644 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 23518 ft MSL (18211 ft AGL)
Wave soaring outlook for Tuesday 09/26......... Poor

Remarks...

Sunrise/Sunset.................... 06:50:14 / 18:52:41 MDT
Total possible sunshine........... 12 hr 2 min 27 sec (722 min 27 sec)
Altitude of sun at 12:50:58 MDT... 49.09 degrees

Upper air data from numerical model forecast valid on 09/25/2017 at 0600 MDT

Freezing level.................. 9215 ft MSL (3908 ft AGL)
Convective condensation level... 8148 ft MSL (2841 ft AGL)
Lifted condensation level....... 8854 ft MSL (3547 ft AGL)
Lifted index.................... +3.8
K index......................... +20.7

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  -58.0 -72.4   220   39   20   1.9   1.0      M     M       M      M    M
 45000  -54.7 -66.5   220   58   30   3.1   1.7      M     M       M      M    M
 40000  -50.2 -58.4   215   76   39   3.1   1.7      M     M       M      M    M
 38000  -48.8 -55.8   210   81   42   2.0   1.1      M     M       M      M    M
 36000  -47.7 -53.9   210   86   44   2.0   1.1      M     M       M      M    M
 34000  -45.8 -50.4   205   89   46   5.3   2.9      M     M       M      M    M
 32000  -42.2 -44.0   205   85   44   5.3   2.9      M     M       M      M    M
 30000  -38.3 -36.9   200   82   42   7.9   4.3   38.2 100.8    19.6      M    M
 29000  -36.0 -32.8   205   80   41   7.9   4.3   37.4  99.3    19.2      M    M
 28000  -33.6 -28.5   205   78   40   7.9   4.3   36.7  98.1    19.0      M    M
 27000  -31.4 -24.5   205   75   39   5.9   3.2   35.9  96.6    18.5      M    M
 26000  -29.6 -21.3   205   72   37   6.1   3.3   34.4  93.9    17.6      M    M
 25000  -27.8 -18.0   205   68   35   6.1   3.3   33.0  91.5    16.7      M    M
 24000  -26.0 -14.8   210   65   33   5.8   3.2   31.8  89.2    15.8      M    M
 23000  -24.3 -11.7   210   61   31   5.8   3.2   30.2  86.4    14.7      M    M
 22000  -22.6  -8.7   210   57   29   5.9   3.2   28.8  83.9    13.7      M    M
 21000  -20.8  -5.4   215   53   27   6.9   3.8   27.6  81.6    12.7      M    M
 20000  -18.8  -1.8   215   49   25   6.8   3.7   26.5  79.6    11.9      M    M
 19500  -17.8  -0.0   215   47   24   6.8   3.8   25.9  78.7    11.5      M    M
 19000  -16.8   1.8   215   45   23   6.8   3.7   25.5  77.9    11.1      M    M
 18500  -15.8   3.6   215   43   22   7.5   4.1   25.0  77.1    10.8      M    M
 18000  -14.7   5.5   215   42   22   7.7   4.2   24.7  76.4    10.5      M    M
 17500  -13.5   7.7   210   42   21   7.8   4.3   24.3  75.8    10.2      M    M
 17000  -12.3   9.9   210   40   21   8.2   4.5   24.0  75.3    10.0      M    M
 16500  -10.6  12.9   210   37   19   8.0   4.4   23.7  74.6     9.7      M    M
 16000   -9.4  15.1   210   34   17   7.7   4.2   23.3  74.0     9.4      M    M
 15500   -8.3  17.1   210   30   15   7.7   4.2   23.0  73.4     9.1      M    M
 15000   -7.4  18.7   215   27   14   5.5   3.0   22.4  72.4     8.6      M    M
 14500   -6.5  20.3   220   26   13   5.6   3.1   21.8  71.2     8.1      M    M
 14000   -5.6  21.9   225   25   13   6.3   3.5   21.1  70.0     7.5      M    M
 13500   -4.7  23.5   230   24   12   6.4   3.5   20.6  69.0     7.1      M    M
 13000   -3.8  25.2   230   22   11   5.0   2.8   20.0  67.9     6.5      M    M
 12500   -3.1  26.4   235   19   10   4.9   2.7   19.1  66.5     5.8      M    M
 12000   -2.5  27.5   240   15    8   2.2   1.2   18.2  64.8     5.0      M    M
 11500   -2.3  27.9   250   11    6   1.4   0.8   16.9  62.4     3.8      M    M
 11000   -2.0  28.4   270    7    4   3.1   1.7   15.6  60.1     2.6      M    M
 10500   -1.5  29.3   305    5    2   4.1   2.3   14.7  58.4     1.6      M    M
 10250   -1.3  29.7   325    5    2   1.6   0.9   14.2  57.5     1.1      M    M
 10000   -1.2  29.8   335    5    2   2.9   1.6   13.5  56.3     0.5      M    M
  9750   -0.8  30.6   350    5    3   6.5   3.5   13.2  55.7     0.1      M    M
  9500   -0.4  31.3   360    5    3   5.7   3.1   12.8  55.1    -0.2    294  1.5
  9250   -0.0  32.0   010    6    3   5.3   2.9   12.5  54.6    -0.5    274  1.4
  9000    0.3  32.5   015    6    3   5.4   3.0   12.2  53.9    -0.9    256  1.3
  8750    0.8  33.4   020    6    3   7.0   3.9   11.9  53.4    -1.2    235  1.2
  8500    1.3  34.3   025    6    3   7.5   4.1   11.7  53.1    -1.4    212  1.1
  8250    1.8  35.2   025    5    3   7.4   4.1   11.5  52.8    -1.6    189  1.0
  8000    2.3  36.1   035    5    3   7.5   4.1   11.4  52.4    -1.8    166  0.8
  7750    2.8  37.0   045    6    3   6.6   3.6   11.2  52.1    -2.0    143  0.7
  7500    3.3  37.9   050    6    3   6.5   3.6   10.9  51.6    -2.3    123  0.6
  7250    3.8  38.8   055    6    3   7.5   4.1   10.7  51.2    -2.6    100  0.5
  7000    4.3  39.7   055    6    3   7.9   4.3   10.5  50.9    -2.8     77  0.4
  6750    4.9  40.8   050    7    3   6.6   3.6   10.4  50.6    -3.0     53  0.3
  6500    5.3  41.5   045    7    3   7.6   4.2   10.1  50.2    -3.3     32  0.2
  6250    6.0  42.8   040    6    3   9.5   5.2   10.0  50.1    -3.4      6  0.0
  6000    6.6  43.9   030    6    3   8.8   4.8   10.0  50.0    -3.5      M    M
  5750    7.2  45.0   015    5    3   9.5   5.2   10.1  49.9    -3.6      M    M
  5500    8.0  46.4   010    5    2  11.3   6.2   10.0  50.0    -3.5      M    M

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

           09/25/2017 at 0900 MDT          |       09/25/2017 at 1200 MDT
                                           |
K index... +21.8  LI... +1.4               | K index... +23.4  LI... +2.0
CAPE... +61.8  CIN... 0.0                  | CAPE... +42.1  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 -57.0 -70.6  220  42 21   1.1   0.6 | -57.3 -71.1  215  42 22   1.5   0.8
 45000 -54.8 -66.6  220  59 30   3.3   1.8 | -54.6 -66.3  220  58 30   3.6   2.0
 40000 -49.9 -57.8  215  81 42   3.2   1.8 | -49.2 -56.6  210  79 41   3.6   2.0
 38000 -48.5 -55.3  210  85 44   2.1   1.1 | -47.6 -53.7  205  84 43   2.3   1.3
 36000 -47.3 -53.1  205  87 45   2.1   1.1 | -46.3 -51.3  200  87 45   2.3   1.3
 34000 -45.5 -49.9  200  89 46   4.9   2.7 | -43.8 -46.8  195  90 46   5.6   3.1
 32000 -42.1 -43.8  200  89 46   5.0   2.7 | -40.5 -40.9  195  91 47   5.6   3.1
 30000 -38.5 -37.3  195  88 45   7.4   4.1 | -37.2 -35.0  195  91 47   5.4   3.0
 29000 -36.3 -33.3  200  85 44   7.4   4.1 | -35.5 -31.9  195  90 46   5.4   3.0
 28000 -34.1 -29.4  200  83 43   7.4   4.1 | -33.9 -29.0  195  89 46   5.4   3.0
 27000 -32.0 -25.6  200  79 41   5.9   3.2 | -32.3 -26.1  200  86 44   4.9   2.7
 26000 -30.2 -22.4  200  74 38   6.0   3.3 | -30.8 -23.4  200  78 40   5.0   2.7
 25000 -28.4 -19.1  205  68 35   6.0   3.3 | -29.3 -20.7  205  71 37   5.0   2.7
 24000 -26.6 -15.9  205  63 32   6.1   3.3 | -27.8 -18.0  210  65 33   6.0   3.3
 23000 -24.8 -12.6  205  58 30   6.2   3.4 | -25.9 -14.6  210  57 30   6.7   3.7
 22000 -22.9  -9.2  210  53 27   6.2   3.4 | -23.9 -11.0  210  50 26   6.8   3.7
 21000 -21.0  -5.8  210  48 25   7.8   4.3 | -21.8  -7.2  215  43 22   8.6   4.7
 20000 -18.8  -1.8  210  43 22   7.7   4.2 | -19.3  -2.7  210  38 19   8.6   4.7
 19500 -17.6   0.3  210  40 21   7.7   4.2 | -18.0  -0.4  210  35 18   8.7   4.7
 19000 -16.5   2.3  210  37 19   7.8   4.3 | -16.7   1.9  210  32 16   8.7   4.8
 18500 -15.4   4.3  210  35 18   6.5   3.6 | -15.6   3.9  210  29 15   6.7   3.7
 18000 -14.5   5.9  210  33 17   6.2   3.4 | -14.7   5.5  210  28 14   6.0   3.3
 17500 -13.6   7.5  210  32 16   6.4   3.5 | -13.3   8.1  210  26 13   7.2   3.9
 17000 -12.6   9.3  215  30 15   7.1   3.9 | -12.2  10.0  210  24 12   7.4   4.1
 16500 -11.1  12.0  215  27 14   7.0   3.9 | -11.1  12.0  210  21 11   6.8   3.7
 16000 -10.1  13.8  215  24 12   7.0   3.9 | -10.3  13.5  210  19 10   5.4   3.0
 15500  -9.0  15.8  215  21 11   7.0   3.9 |  -9.5  14.9  210  16  8   5.4   3.0
 15000  -8.1  17.4  215  19 10   6.5   3.5 |  -8.7  16.3  215  14  7   6.0   3.3
 14500  -7.1  19.2  215  17  9   6.6   3.6 |  -7.8  18.0  210  13  7   6.0   3.3
 14000  -6.2  20.8  215  16  8   6.0   3.3 |  -6.9  19.6  210  12  6   5.8   3.2
 13500  -5.3  22.5  220  15  8   6.1   3.4 |  -6.1  21.0  205  11  6   5.9   3.2
 13000  -4.5  23.9  220  14  7   4.1   2.3 |  -5.3  22.5  200  11  5   4.9   2.7
 12500  -4.0  24.8  225  13  7   3.8   2.1 |  -4.6  23.7  195  10  5   4.8   2.6
 12000  -3.4  25.9  225  11  6   3.0   1.6 |  -4.0  24.8  195   9  4   3.8   2.1
 11500  -3.1  26.4  230   8  4   2.7   1.5 |  -3.5  25.7  205   5  3   3.4   1.9
 11000  -2.6  27.3  245   5  3   4.5   2.5 |  -2.9  26.8  240   2  1   4.9   2.7
 10500  -1.9  28.6  295   2  1   5.4   3.0 |  -2.1  28.2  025   2  1   5.5   3.0
 10250  -1.5  29.3  345   3  1   3.3   1.8 |  -1.8  28.8  035   3  2   4.2   2.3
 10000  -1.4  29.5  355   3  2   3.9   2.1 |  -1.5  29.3  035   4  2   5.6   3.1
  9750  -0.9  30.4  360   4  2   6.5   3.5 |  -0.9  30.4  025   4  2   7.9   4.3
  9500  -0.5  31.1  005   4  2   5.9   3.2 |  -0.4  31.3  015   4  2   7.7   4.2
  9250  -0.1  31.8  010   5  3   5.6   3.1 |   0.1  32.2  010   4  2   6.3   3.5
  9000   0.3  32.5  010   5  3   6.0   3.3 |   0.5  32.9  005   4  2   4.9   2.7
  8750   0.8  33.4  005   5  3   7.7   4.2 |   0.9  33.6  005   4  2   6.1   3.4
  8500   1.4  34.5  005   5  3   8.2   4.5 |   1.4  34.5  010   3  2   6.5   3.6
  8250   1.9  35.4  005   5  2   7.6   4.2 |   1.8  35.2  015   3  2   5.7   3.1
  8000   2.5  36.5  015   4  2   7.3   4.0 |   2.2  36.0  040   3  2   5.3   2.9
  7750   3.0  37.4  030   4  2   6.3   3.5 |   2.6  36.7  060   4  2   5.5   3.0
  7500   3.4  38.1  045   4  2   6.0   3.3 |   3.0  37.4  070   5  2   5.9   3.2
  7250   3.8  38.8  055   5  3   6.8   3.7 |   3.4  38.1  075   5  3   6.5   3.6
  7000   4.3  39.7  060   6  3   7.0   3.8 |   3.9  39.0  080   6  3   6.5   3.5
  6750   4.8  40.6  065   7  4   6.1   3.4 |   4.4  39.9  085   7  3   7.2   4.0
  6500   5.2  41.4  065   8  4   7.5   4.1 |   5.0  41.0  080   6  3   9.4   5.2
  6250   5.9  42.6  055   7  4   9.4   5.2 |   5.7  42.3  075   6  3  10.4   5.7
  6000   6.5  43.7  050   6  3   8.5   4.7 |   6.4  43.5  070   5  3   9.9   5.4
  5750   7.1  44.8  040   6  3   9.9   5.4 |   7.1  44.8  065   5  3  10.8   5.9
  5500   8.0  46.4  035   5  3  13.6   7.4 |   8.0  46.4  065   5  3  13.9   7.6

           09/25/2017 at 1500 MDT          |       09/25/2017 at 1800 MDT
                                           |
K index... +22.2  LI... +1.0               | K index... +20.3  LI... +0.4
CAPE... +47.5  CIN... 0.0                  | CAPE... +2.6  CIN... -0.4
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -56.3 -69.3  215  41 21   2.1   1.2 | -56.1 -69.0  225  38 19   2.7   1.5
 45000 -53.0 -63.4  220  54 28   2.7   1.5 | -52.1 -61.8  225  48 24   2.6   1.4
 40000 -49.0 -56.2  220  69 36   2.6   1.5 | -48.2 -54.8  225  56 29   2.6   1.4
 38000 -47.8 -54.0  215  74 38   1.7   0.9 | -47.2 -53.0  225  62 32   1.4   0.8
 36000 -46.8 -52.2  210  80 41   1.7   0.9 | -46.3 -51.3  220  68 35   1.4   0.8
 34000 -44.5 -48.1  205  84 43   6.0   3.3 | -44.8 -48.6  220  73 38   5.3   2.9
 32000 -40.9 -41.6  205  85 44   6.0   3.3 | -41.2 -42.2  220  75 39   5.4   3.0
 30000 -37.6 -35.7  205  84 43   5.0   2.7 | -38.3 -36.9  220  72 37   3.9   2.2
 29000 -36.1 -33.0  205  80 41   5.0   2.7 | -37.1 -34.8  220  66 34   3.9   2.2
 28000 -34.6 -30.3  205  77 40   5.0   2.7 | -35.9 -32.6  225  61 31   3.9   2.2
 27000 -33.1 -27.6  205  73 38   4.2   2.3 | -34.6 -30.3  225  55 28   5.7   3.1
 26000 -31.9 -25.4  205  65 34   4.1   2.3 | -32.9 -27.2  230  47 24   5.9   3.2
 25000 -30.6 -23.1  210  58 30   4.1   2.3 | -31.1 -24.0  235  40 21   5.9   3.3
 24000 -29.4 -20.9  210  50 26   6.2   3.4 | -29.4 -20.9  240  34 17   6.9   3.8
 23000 -27.1 -16.8  210  44 23   7.8   4.3 | -27.1 -16.8  240  29 15   7.7   4.2
 22000 -24.8 -12.6  205  37 19   8.0   4.4 | -24.8 -12.6  240  25 13   7.7   4.2
 21000 -22.4  -8.3  200  32 16   8.3   4.5 | -22.6  -8.7  245  22 11   6.7   3.7
 20000 -20.0  -4.0  205  28 15   8.3   4.6 | -20.6  -5.1  245  19 10   6.7   3.7
 19500 -18.7  -1.7  205  27 14   8.3   4.6 | -19.6  -3.3  245  17  9   6.7   3.7
 19000 -17.5   0.5  210  25 13   8.4   4.6 | -18.6  -1.5  245  16  8   6.7   3.7
 18500 -16.4   2.5  215  24 12   6.3   3.5 | -17.6   0.3  250  14  7   6.9   3.8
 18000 -15.6   3.9  215  23 12   5.6   3.1 | -16.6   2.1  255  13  7   6.9   3.8
 17500 -14.7   5.5  220  22 11   5.9   3.2 | -15.6   3.9  265  12  6   7.0   3.9
 17000 -13.0   8.6  225  20 10   8.1   4.5 | -13.9   7.0  280  11  6   7.5   4.1
 16500 -11.8  10.8  225  19 10   7.8   4.3 | -12.8   9.0  290  11  6   7.4   4.1
 16000 -10.8  12.6  230  19 10   6.9   3.8 | -11.7  10.9  295  11  6   7.3   4.0
 15500  -9.8  14.4  235  18 10   6.9   3.8 | -10.6  12.9  300  12  6   7.3   4.0
 15000  -8.8  16.2  235  18  9   6.6   3.6 |  -9.5  14.9  300  12  6   8.4   4.6
 14500  -7.8  18.0  230  17  9   6.6   3.6 |  -8.2  17.2  300  13  7   8.4   4.6
 14000  -6.8  19.8  230  16  8   7.1   3.9 |  -7.0  19.4  300  13  7   7.7   4.2
 13500  -5.8  21.6  225  14  7   7.2   4.0 |  -5.9  21.4  295  13  7   7.8   4.3
 13000  -4.8  23.4  220  13  7   6.6   3.6 |  -4.8  23.4  295  13  7   7.4   4.0
 12500  -3.9  25.0  220  11  6   6.6   3.6 |  -3.7  25.3  290  13  7   7.4   4.1
 12000  -3.0  26.6  220  10  5   3.4   1.8 |  -2.7  27.1  290  13  7   6.2   3.4
 11500  -2.7  27.1  235   7  4   2.3   1.3 |  -1.9  28.6  285  12  6   6.0   3.3
 11000  -2.4  27.7  255   5  2   3.3   1.8 |  -1.0  30.2  280  11  6   5.3   2.9
 10500  -1.8  28.8  275   2  1   4.2   2.3 |  -0.3  31.5  275  10  5   6.0   3.3
 10250  -1.6  29.1  315   1  1   1.4   0.8 |   0.1  32.2  275   9  5   1.8   1.0
 10000  -1.5  29.3  340   1  1   3.4   1.9 |   0.0  32.0  270   9  4   1.5   0.8
  9750  -1.0  30.2  360   2  1   7.7   4.2 |   0.4  32.7  270   8  4   5.5   3.0
  9500  -0.6  30.9  010   2  1   6.9   3.8 |   0.7  33.3  265   7  3   4.7   2.6
  9250  -0.1  31.8  020   2  1   6.2   3.4 |   1.0  33.8  260   6  3   4.1   2.3
  9000   0.3  32.5  020   3  1   5.2   2.8 |   1.3  34.3  255   5  3   3.5   1.9
  8750   0.7  33.3  020   3  2   6.0   3.3 |   1.5  34.7  255   5  2   4.5   2.4
  8500   1.2  34.2  025   3  2   6.3   3.4 |   1.9  35.4  255   4  2   4.7   2.6
  8250   1.6  34.9  030   4  2   6.2   3.4 |   2.2  36.0  250   4  2   5.5   3.0
  8000   2.1  35.8  045   4  2   6.3   3.4 |   2.6  36.7  245   3  2   6.2   3.4
  7750   2.5  36.5  055   4  2   5.3   2.9 |   3.0  37.4  245   3  1   5.3   2.9
  7500   2.8  37.0  065   5  2   5.6   3.1 |   3.4  38.1  235   2  1   5.5   3.0
  7250   3.3  37.9  075   5  3   7.5   4.1 |   3.8  38.8  220   2  1   6.6   3.6
  7000   3.9  39.0  080   6  3   7.7   4.2 |   4.3  39.7  190   2  1   6.5   3.6
  6750   4.4  39.9  085   6  3   8.1   4.4 |   4.7  40.5  170   3  1   7.5   4.1
  6500   5.0  41.0  085   6  3   9.7   5.3 |   5.3  41.5  160   3  2   9.5   5.2
  6250   5.8  42.4  085   6  3  10.6   5.8 |   6.1  43.0  160   3  2  10.1   5.6
  6000   6.5  43.7  085   5  3  10.2   5.6 |   6.8  44.2  155   3  1   9.6   5.3
  5750   7.2  45.0  085   5  3  10.2   5.6 |   7.6  45.7  155   3  1  11.1   6.1
  5500   8.0  46.4  085   5  2  11.7   6.4 |   8.5  47.3  150   3  1  14.6   8.0
________________________________________________________________________________

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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