Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 111325
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0724 MDT Thursday, September 11, 2014

This forecast is for Thursday, September 11, 2014:

If the trigger temperature of 63.4 F/17.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6998 ft MSL (1713 ft AGL)

Forecast maximum temperature................... 53.0 F/12.1 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................. None
Thermal soaring outlook for Friday 09/12....... Fair

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... Becoming excellent
Height of stable layer (12-18K ft MSL)......... 14632 ft MSL (9347 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 16600 ft MSL (11315 ft AGL)
Wave soaring outlook for Friday 09/12.......... Excellent

Remarks... Low clouds and drizzle

Sunrise/Sunset.................... 06:36:49 / 19:16:05 MDT
Total possible sunshine........... 12 hr 39 min 16 sec (759 min 16 sec)
Altitude of sun at 12:55:58 MDT... 54.60 degrees

Upper air data from rawinsonde observation taken on 09/11/2014 at 0600 MDT

Freezing level.................. 12803 ft MSL (7518 ft AGL)
Convective condensation level... 12374 ft MSL (7089 ft AGL)
Lifted condensation level....... 8083 ft MSL (2798 ft AGL)
Lifted index.................... +10.0
K index......................... -1.4

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  -66.4 -87.5   280   70   36   3.7   2.0   84.5 184.0    42.1      M    M
 45000  -58.0 -72.4   260   77   40   2.4   1.3   72.5 162.6    37.9      M    M
 40000  -55.4 -67.7   260   75   39   5.4   3.0   54.2 129.6    28.3      M    M
 38000  -52.8 -63.0   260   69   36   5.5   3.0   49.4 121.0    25.8      M    M
 36000  -48.2 -54.8   255   63   32   7.7   4.2   47.6 117.6    25.2      M    M
 34000  -43.5 -46.3   260   59   30   7.7   4.2   45.9 114.7    24.7      M    M
 32000  -38.1 -36.6   265   57   29   9.2   5.0   45.2 113.4    24.8      M    M
 30000  -32.3 -26.1   275   56   29   7.4   4.1   44.3 111.7    24.7      M    M
 29000  -30.1 -22.2   275   54   28   7.4   4.1   43.1 109.6    24.2      M    M
 28000  -27.9 -18.2   275   51   26   7.4   4.1   42.1 107.8    23.7      M    M
 27000  -25.7 -14.3   270   49   25   7.4   4.1   41.3 106.3    23.3      M    M
 26000  -23.5 -10.3   270   47   24   7.4   4.1   40.5 104.9    23.0      M    M
 25000  -21.2  -6.2   270   45   23   7.8   4.3   39.9 103.7    22.7      M    M
 24000  -18.7  -1.7   275   44   23   8.6   4.7   39.3 102.7    22.5      M    M
 23000  -16.2   2.8   275   46   24   6.6   3.6   38.9 102.0    22.4      M    M
 22000  -14.9   5.2   275   43   22   4.0   2.2   36.8  98.2    20.9      M    M
 21000  -13.8   7.2   280   39   20   3.8   2.1   34.8  94.6    19.4      M    M
 20000  -11.8  10.8   280   36   19   7.4   4.1   33.7  92.7    18.7      M    M
 19500  -10.7  12.7   275   33   17   8.0   4.4   33.3  91.9    18.5      M    M
 19000   -9.9  14.2   265   31   16   3.8   2.1   32.5  90.5    17.9      M    M
 18500   -9.1  15.6   260   29   15   6.6   3.6   31.8  89.3    17.4      M    M
 18000   -8.0  17.6   250   28   14   7.8   4.3   31.5  88.6    17.1      M    M
 17500   -6.8  19.8   255   28   14   7.8   4.3   31.1  88.0    16.9      M    M
 17000   -5.6  21.9   260   28   14   7.8   4.3   30.8  87.4    16.6      M    M
 16500   -4.5  23.9   270   28   14   7.8   4.3   30.4  86.8    16.4      M    M
 16000   -3.3  26.1   275   29   15   8.4   4.6   30.1  86.2    16.3      M    M
 15500   -2.2  28.0   275   28   14   5.0   2.8   29.7  85.4    16.0      M    M
 15000   -1.1  30.0   275   26   13  -1.8  -1.0   28.4  83.2    15.0      M    M
 14500   -3.9  25.0   275   25   13  -6.4  -3.5   24.2  75.6    10.8      M    M
 14000   -2.8  27.0   275   24   12   7.5   4.1   23.8  74.9    10.5      M    M
 13500   -1.6  29.1   275   22   11   8.6   4.7   23.6  74.6    10.3      M    M
 13000   -0.3  31.5   275   20   10   8.7   4.8   23.5  74.3    10.2      M    M
 12500    1.0  33.8   280   18    9   8.7   4.8   23.3  74.0    10.1      M    M
 12000    2.3  36.1   280   16    8   8.7   4.8   23.2  73.8    10.0      M    M
 11500    3.6  38.5   280   13    6   8.6   4.7   23.0  73.4     9.9      M    M
 11000    4.8  40.6   280   10    5   5.5   3.0   22.8  73.1     9.7      M    M
 10500    5.2  41.4   280   11    6   3.0   1.6   21.7  71.1     8.7      M    M
 10250    5.4  41.7   280   11    6   2.5   1.4   21.2  70.1     8.2      M    M
 10000    5.6  42.1   275   11    6   0.7   0.4   20.6  69.0     7.6      M    M
  9750    5.6  42.1   275   11    6  -1.0  -0.6   19.7  67.5     6.9      M    M
  9500    5.5  41.9   275   12    6  -0.9  -0.5   18.9  66.0     6.1      M    M
  9250    5.4  41.7   270   12    6  -0.9  -0.5   18.1  64.5     5.4      M    M
  9000    5.3  41.5   270   12    6  -1.0  -0.5   17.2  63.0     4.6      M    M
  8750    5.3  41.5   290   10    5   3.4   1.9   16.5  61.7     3.8      M    M
  8500    5.7  42.3   310   10    5   7.9   4.3   16.3  61.3     3.4      M    M
  8250    6.0  42.8   330   10    5   3.9   2.2   16.0  60.8     3.1      M    M
  8000    5.9  42.6   345   12    6  -6.2  -3.4   15.2  59.4     2.2      M    M
  7750    5.4  41.7   345   13    6  -1.2  -0.7   14.0  57.1     1.0      M    M
  7500    5.8  42.4   340   13    7   7.1   3.9   13.6  56.5     0.7      M    M
  7250    6.2  43.2   340   13    7   5.0   2.7   13.3  55.9     0.3      M    M
  7000    6.6  43.9   340   14    7   5.6   3.0   13.0  55.3     0.0      M    M
  6750    7.0  44.6   340   14    7   5.4   3.0   12.6  54.7    -0.3    157  0.8
  6500    7.4  45.3   340   13    7   5.4   3.0   12.3  54.1    -0.7    138  0.7
  6250    7.8  46.0   345   13    6   5.6   3.1   12.0  53.5    -1.0    119  0.6
  6000    8.2  46.8   345   12    6   5.0   2.7   11.7  53.0    -1.3    100  0.5
  5750    8.5  47.3   345    8    4   7.2   3.9   11.3  52.4    -1.7     81  0.4
  5500    9.4  48.9   345    4    2  14.9   8.2   11.4  52.5    -1.6     49  0.2

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

           09/11/2014 at 0900 MDT          |       09/11/2014 at 1200 MDT
                                           |
K index... +17.1  LI... +2.7               | K index... +7.6  LI... +2.7
CAPE... 0.0  CIN... -0.7                   | CAPE... 0.0  CIN... M
                                           |
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 -63.8 -82.8  270  57 29   3.1   1.7 | -64.0 -83.2  270  56 29   3.4   1.9
 45000 -59.3 -74.7  270  77 40   2.5   1.4 | -58.9 -74.0  270  78 40   3.5   1.9
 40000 -55.2 -67.4  260  71 37   5.6   3.1 | -53.3 -63.9  260  73 38   4.0   2.2
 38000 -51.9 -61.4  260  66 34   5.6   3.1 | -50.9 -59.6  260  69 35   4.0   2.2
 36000 -48.6 -55.5  260  61 31   5.6   3.1 | -48.5 -55.3  260  64 33   4.0   2.2
 34000 -44.0 -47.2  260  58 30   8.6   4.7 | -44.4 -47.9  260  61 31   8.3   4.5
 32000 -38.8 -37.8  265  56 29   8.6   4.7 | -39.4 -38.9  260  58 30   8.3   4.5
 30000 -33.7 -28.7  270  53 27   8.5   4.7 | -34.3 -29.7  265  55 28   8.6   4.7
 29000 -30.5 -22.9  270  51 26   8.5   4.7 | -31.1 -24.0  265  54 28   8.6   4.7
 28000 -27.9 -18.2  275  50 26   8.4   4.6 | -28.5 -19.3  265  53 27   8.5   4.6
 27000 -25.6 -14.1  275  48 25   7.9   4.3 | -26.2 -15.2  270  51 26   7.7   4.2
 26000 -23.2  -9.8  275  47 24   7.9   4.3 | -23.9 -11.0  270  50 26   7.7   4.2
 25000 -20.8  -5.4  275  45 23   8.0   4.4 | -21.6  -6.9  270  48 25   7.8   4.3
 24000 -18.9  -2.0  275  43 22   5.9   3.2 | -19.5  -3.1  270  46 24   6.3   3.5
 23000 -17.1   1.2  275  41 21   5.9   3.2 | -17.7   0.1  270  44 23   6.3   3.5
 22000 -15.4   4.3  280  40 20   5.9   3.2 | -15.8   3.6  275  41 21   6.3   3.5
 21000 -13.7   7.3  280  38 19   5.6   3.1 | -14.0   6.8  275  39 20   6.0   3.3
 20000 -12.0  10.4  280  35 18   5.6   3.1 | -12.2  10.0  275  37 19   6.1   3.3
 19500 -11.2  11.8  280  34 18   5.6   3.1 | -11.3  11.7  275  36 19   6.1   3.3
 19000 -10.4  13.3  280  33 17   5.6   3.1 | -10.4  13.3  270  35 18   6.4   3.5
 18500  -9.5  14.9  275  32 16   5.6   3.1 |  -9.4  15.1  270  34 17   6.7   3.7
 18000  -8.7  16.3  275  30 15   5.7   3.1 |  -8.4  16.9  270  33 17   6.7   3.7
 17500  -8.0  17.6  270  28 14   4.8   2.6 |  -7.4  18.7  270  31 16   7.0   3.9
 17000  -7.3  18.9  265  26 13   4.9   2.7 |  -6.3  20.7  270  30 15   7.0   3.8
 16500  -6.6  20.1  265  24 12   5.3   2.9 |  -5.3  22.5  265  29 15   6.9   3.8
 16000  -5.8  21.6  260  21 11   5.6   3.1 |  -4.3  24.3  265  28 15   6.9   3.8
 15500  -5.0  23.0  255  19 10   6.4   3.5 |  -3.3  26.1  265  28 14   6.8   3.7
 15000  -3.8  25.2  255  17  9   9.0   4.9 |  -2.3  27.9  270  29 15   6.3   3.5
 14500  -1.9  28.6  260  16  8   8.9   4.9 |  -0.9  30.4  270  31 16   6.4   3.5
 14000  -0.5  31.1  270  18  9   8.9   4.9 |  -0.0  32.0  275  32 16   6.5   3.6
 13500   0.9  33.6  275  21 11   8.5   4.6 |   0.8  33.4  275  33 17   7.0   3.8
 13000   2.0  35.6  275  22 11   7.4   4.1 |   1.9  35.4  275  30 15   8.0   4.4
 12500   3.0  37.4  275  23 12   7.6   4.2 |   3.0  37.4  275  27 14   8.2   4.5
 12000   4.2  39.6  280  23 12   8.4   4.6 |   4.3  39.7  270  24 12   9.4   5.2
 11500   5.4  41.7  280  23 12   8.2   4.5 |   5.7  42.3  270  22 11   9.2   5.0
 11000   6.4  43.5  275  22 11   6.3   3.5 |   6.9  44.4  270  20 10   6.6   3.6
 10500   7.2  45.0  270  19 10   5.8   3.2 |   7.8  46.0  265  16  8   5.9   3.3
 10250   7.6  45.7  270  18  9   3.6   2.0 |   8.2  46.8  260  15  8   2.9   1.6
 10000   7.8  46.0  270  18  9   5.1   2.8 |   8.4  47.1  260  15  7   4.6   2.5
  9750   8.3  46.9  265  16  8   7.3   4.0 |   8.8  47.8  255  13  7   7.2   3.9
  9500   8.8  47.8  265  15  8   5.8   3.2 |   9.3  48.7  250  12  6   5.9   3.2
  9250   9.1  48.4  260  14  7   3.5   1.9 |   9.6  49.3  245  11  6   3.5   1.9
  9000   9.3  48.7  260  13  7   2.6   1.4 |   9.8  49.6  240  10  5   2.9   1.6
  8750   9.5  49.1  260  12  6   3.7   2.0 |  10.1  50.2  235   9  5   4.5   2.4
  8500   9.7  49.5  260  10  5   0.9   0.5 |  10.3  50.5  225   8  4   2.2   1.2
  8250   9.6  49.3  265   9  5  -2.9  -1.6 |  10.3  50.5  225   7  3  -0.9  -0.5
  8000   9.3  48.7  270   8  4  -3.3  -1.8 |  10.2  50.4  220   5  3  -1.9  -1.1
  7750   9.0  48.2  280   7  4  -3.7  -2.0 |   9.9  49.8  220   4  2  -3.5  -1.9
  7500   8.6  47.5  290   7  3  -7.9  -4.3 |   9.6  49.3  215   2  1  -5.0  -2.7
  7250   7.8  46.0  300   6  3 -10.0  -5.5 |   9.2  48.6  000   0  0  -4.9  -2.7
  7000   7.1  44.8  310   6  3 -11.8  -6.4 |   8.7  47.7  050   1  1  -6.6  -3.6
  6750   6.1  43.0  325   6  3 -10.3  -5.7 |   8.1  46.6  045   3  1  -6.0  -3.3
  6500   5.8  42.4  330   5  3   3.4   1.9 |   8.0  46.4  040   4  2   6.2   3.4
  6250   6.4  43.5  330   4  2   9.7   5.3 |   8.8  47.8  040   4  2  12.5   6.8
  6000   7.0  44.6  325   3  2   8.0   4.4 |   9.6  49.3  035   4  2  11.4   6.3
  5750   7.6  45.7  325   3  1  12.2   6.7 |  10.6  51.1  030   4  2  17.1   9.4
  5500   8.7  47.7  320   2  1  17.4   9.5 |  12.1  53.8  030   4  2  22.7  12.5

           09/11/2014 at 1500 MDT          |       09/11/2014 at 1800 MDT
                                           |
K index... +20.6  LI... -1.0               | K index... +24.5  LI... -3.9
CAPE... +38.2  CIN... -162.6               | CAPE... +371.8  CIN... -17.6
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -64.9 -84.8  270  55 29   3.7   2.0 | -65.3 -85.5  265  57 29   4.2   2.3
 45000 -59.1 -74.4  270  79 41   4.5   2.4 | -58.8 -73.8  270  75 39   4.8   2.6
 40000 -52.2 -62.0  265  71 37   3.7   2.0 | -51.3 -60.3  265  73 37   3.9   2.1
 38000 -50.0 -58.0  260  69 35   3.6   2.0 | -49.0 -56.2  265  69 36   3.8   2.1
 36000 -47.9 -54.2  255  67 34   3.6   2.0 | -46.7 -52.1  265  66 34   3.8   2.1
 34000 -44.2 -47.6  255  64 33   7.6   4.2 | -43.4 -46.1  265  64 33   6.5   3.6
 32000 -39.6 -39.3  255  62 32   7.6   4.2 | -39.5 -39.1  265  62 32   6.5   3.6
 30000 -34.7 -30.5  260  59 30   8.7   4.8 | -35.1 -31.2  270  60 31   7.9   4.4
 29000 -31.4 -24.5  260  58 30   8.7   4.8 | -32.1 -25.8  270  58 30   8.0   4.4
 28000 -28.8 -19.8  265  57 29   8.6   4.7 | -29.7 -21.5  270  56 29   8.0   4.4
 27000 -26.4 -15.5  265  56 29   7.6   4.2 | -27.4 -17.3  270  56 29   7.5   4.1
 26000 -24.1 -11.4  265  54 28   7.6   4.2 | -25.2 -13.4  270  56 29   7.5   4.1
 25000 -21.9  -7.4  270  53 27   7.7   4.2 | -23.0  -9.4  275  55 28   7.5   4.1
 24000 -19.8  -3.6  270  52 27   6.5   3.5 | -20.9  -5.6  275  55 28   6.4   3.5
 23000 -17.9  -0.2  270  51 26   6.4   3.5 | -19.0  -2.2  275  54 28   6.4   3.5
 22000 -16.0   3.2  270  50 26   6.6   3.6 | -17.1   1.2  270  54 28   6.5   3.6
 21000 -14.4   6.1  270  49 25   4.6   2.5 | -15.5   4.1  270  52 27   5.2   2.8
 20000 -13.1   8.4  270  49 25   4.6   2.5 | -14.0   6.8  265  50 26   5.2   2.9
 19500 -12.4   9.7  270  48 25   4.7   2.6 | -13.2   8.2  265  49 25   5.4   3.0
 19000 -11.8  10.8  270  48 25   5.7   3.1 | -12.5   9.5  265  48 25   7.7   4.2
 18500 -10.8  12.6  270  47 24   6.8   3.7 | -11.0  12.2  260  46 24  10.2   5.6
 18000  -9.8  14.4  270  47 24   6.7   3.7 |  -9.5  14.9  260  45 23  10.6   5.8
 17500  -8.6  16.5  270  45 23   8.9   4.9 |  -8.1  17.4  260  43 22   8.4   4.6
 17000  -7.4  18.7  265  43 22   8.8   4.8 |  -6.9  19.6  260  41 21   8.7   4.8
 16500  -6.1  21.0  265  41 21   8.8   4.8 |  -5.6  21.9  260  40 20   8.9   4.9
 16000  -4.9  23.2  265  38 20   8.8   4.8 |  -4.3  24.3  260  38 19   9.1   5.0
 15500  -3.6  25.5  260  36 18   8.9   4.9 |  -3.0  26.6  260  36 18   8.9   4.9
 15000  -2.3  27.9  260  34 17   9.0   5.0 |  -1.8  28.8  260  34 17   7.9   4.3
 14500  -0.3  31.5  260  31 16   8.9   4.9 |  -0.1  31.8  260  30 16   7.3   4.0
 14000   1.0  33.8  260  29 15   8.7   4.8 |   0.9  33.6  255  28 14   6.4   3.5
 13500   2.3  36.1  260  27 14   8.6   4.7 |   1.8  35.2  255  26 13   6.0   3.3
 13000   3.5  38.3  255  25 13   7.9   4.3 |   2.4  36.3  250  23 12   4.4   2.4
 12500   4.6  40.3  255  23 12   7.8   4.3 |   3.0  37.4  240  21 11   4.5   2.5
 12000   5.6  42.1  250  21 11   6.2   3.4 |   3.6  38.5  230  19 10   5.2   2.8
 11500   6.5  43.7  245  19 10   6.4   3.5 |   4.3  39.7  220  18  9   5.2   2.8
 11000   7.2  45.0  240  17  9   4.2   2.3 |   4.6  40.3  220  15  8   0.2   0.1
 10500   7.8  46.0  230  16  8   4.4   2.4 |   4.7  40.5  225  10  5   0.4   0.2
 10250   8.1  46.6  225  15  8   2.5   1.4 |   4.7  40.5  225   9  4  -0.7  -0.4
 10000   8.2  46.8  220  14  7   1.6   0.9 |   4.7  40.5  230   7  4   1.4   0.7
  9750   8.3  46.9  215  12  6   2.4   1.3 |   4.9  40.8  240   5  2   3.6   1.9
  9500   8.3  46.9  200  10  5   1.8   1.0 |   5.1  41.2  275   3  1   2.9   1.6
  9250   8.3  46.9  185   8  4  -1.8  -1.0 |   5.3  41.5  325   3  1   2.6   1.4
  9000   8.0  46.4  165   6  3  -3.0  -1.6 |   5.5  41.9  350   3  2   3.1   1.7
  8750   7.8  46.0  125   4  2  -2.4  -1.3 |   5.8  42.4  010   4  2   4.2   2.3
  8500   7.6  45.7  075   5  3  -0.3  -0.1 |   6.1  43.0  025   6  3   3.6   2.0
  8250   7.7  45.9  060   7  4   4.6   2.5 |   6.3  43.3  040   7  4   2.8   1.6
  8000   8.1  46.6  045   8  4   6.7   3.7 |   6.5  43.7  050   9  5   2.6   1.4
  7750   8.7  47.7  040   9  5   7.6   4.2 |   6.7  44.1  055  11  6   2.3   1.2
  7500   9.3  48.7  040   9  5   9.4   5.1 |   6.8  44.2  060  13  7   0.7   0.4
  7250  10.0  50.0  040   9  5  10.6   5.8 |   6.8  44.2  055  15  8  -0.1  -0.1
  7000  10.8  51.4  035   9  5  10.3   5.7 |   6.8  44.2  050  18  9  -0.5  -0.3
  6750  11.6  52.9  035   9  5  10.7   5.9 |   6.9  44.4  050  20 10   2.9   1.6
  6500  12.4  54.3  035   9  5  10.7   5.9 |   7.3  45.1  045  20 10   8.6   4.7
  6250  13.2  55.8  035   9  5  11.3   6.2 |   8.0  46.4  040  19 10   9.2   5.1
  6000  14.0  57.2  030   9  5   9.2   5.0 |   8.6  47.5  035  18  9   9.7   5.3
  5750  14.7  58.5  030   9  5  14.1   7.8 |   9.4  48.9  030  17  9  13.0   7.1
  5500  16.3  61.3  030   9  5  28.7  15.7 |  10.5  50.9  030  15  8  16.3   8.9
________________________________________________________________________________

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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