Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 110109
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1909 MDT Wednesday, September 10, 2014

This forecast is for Thursday, September 11, 2014:

If the trigger temperature of 71.0 F/21.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5667 ft MSL (380 ft AGL)

Forecast maximum temperature................... 62.0 F/17.1 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................. 5453 ft MSL (166 ft AGL)
Thermal soaring outlook for Friday 09/12....... Poor

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 14378 ft MSL (9091 ft AGL)
Wave soaring outlook for Friday 09/12.......... Fair

Remarks...

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 numerical model forecast valid on 09/11/2014 at 0600 MDT

Freezing level.................. 14408 ft MSL (9121 ft AGL)
Convective condensation level... 14969 ft MSL (9682 ft AGL)
Lifted condensation level....... 10611 ft MSL (5324 ft AGL)
Lifted index.................... +6.0
K index......................... +5.6

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  -63.8 -82.8   275   60   31   2.7   1.5      M     M       M      M    M
 45000  -59.9 -75.8   270   78   40   2.3   1.3      M     M       M      M    M
 40000  -56.0 -68.8   265   72   37   6.8   3.7      M     M       M      M    M
 38000  -52.0 -61.6   265   68   35   6.7   3.7      M     M       M      M    M
 36000  -48.0 -54.4   265   64   33   6.7   3.7      M     M       M      M    M
 34000  -43.4 -46.1   265   59   30   8.0   4.4      M     M       M      M    M
 32000  -38.6 -37.5   270   54   28   8.0   4.4      M     M       M      M    M
 30000  -33.7 -28.7   275   49   25   8.2   4.5   42.7 108.9    19.8      M    M
 29000  -31.3 -24.3   275   47   24   8.2   4.5   42.1 107.8    19.5      M    M
 28000  -28.2 -18.8   280   45   23   8.0   4.4   41.5 106.8    19.4      M    M
 27000  -25.9 -14.6   280   44   23   7.4   4.1   40.6 105.1    18.8      M    M
 26000  -23.7 -10.7   280   44   23   7.5   4.1   39.7 103.5    18.4      M    M
 25000  -21.5  -6.7   285   43   22   7.5   4.1   38.9 102.1    17.9      M    M
 24000  -19.5  -3.1   285   42   21   6.4   3.5   37.8 100.1    17.2      M    M
 23000  -17.5   0.5   285   39   20   6.4   3.5   36.6  97.8    16.4      M    M
 22000  -15.6   3.9   285   36   19   6.5   3.5   35.5  95.8    15.6      M    M
 21000  -13.7   7.3   285   34   17   6.3   3.5   34.2  93.6    14.7      M    M
 20000  -11.9  10.6   285   31   16   6.3   3.5   33.0  91.3    13.8      M    M
 19500  -10.9  12.4   285   30   16   6.3   3.5   32.4  90.3    13.4      M    M
 19000  -10.0  14.0   280   29   15   6.3   3.4   31.8  89.3    13.0      M    M
 18500   -9.1  15.6   280   28   14   6.2   3.4   31.2  88.2    12.5      M    M
 18000   -8.1  17.4   280   27   14   6.1   3.4   30.6  87.1    12.1      M    M
 17500   -7.1  19.2   280   26   13   7.3   4.0   30.1  86.2    11.7      M    M
 17000   -6.1  21.0   275   25   13   7.2   3.9   29.7  85.4    11.3      M    M
 16500   -5.0  23.0   275   24   13   7.3   4.0   29.2  84.6    11.0      M    M
 16000   -3.9  25.0   275   24   12   7.3   4.0   28.8  83.9    10.7      M    M
 15500   -2.8  27.0   275   23   12   7.4   4.1   28.4  83.1    10.4      M    M
 15000   -1.7  28.9   275   23   12   7.9   4.3   28.1  82.5    10.1      M    M
 14500    0.1  32.2   280   24   12   7.0   3.9   27.6  81.7     9.8      M    M
 14000    1.0  33.8   285   26   13   6.2   3.4   27.0  80.6     9.2      M    M
 13500    1.9  35.4   285   27   14   5.9   3.2   26.4  79.6     8.7      M    M
 13000    2.6  36.7   285   28   15   5.1   2.8   25.7  78.3     8.0      M    M
 12500    3.3  37.9   285   30   15   5.4   3.0   25.0  77.0     7.3      M    M
 12000    4.1  39.4   285   30   15   6.6   3.6   24.4  75.9     6.7      M    M
 11500    4.9  40.8   285   30   15   6.7   3.7   23.9  75.0     6.1      M    M
 11000    5.9  42.6   285   28   15   7.4   4.1   23.5  74.2     5.7      M    M
 10500    7.0  44.6   285   26   14   5.1   2.8   23.1  73.6     5.3      M    M
 10250    7.2  45.0   285   26   13   4.9   2.7   22.6  72.8     4.8      M    M
 10000    7.8  46.0   285   25   13  10.0   5.5   22.5  72.5     4.7      M    M
  9750    8.6  47.5   285   24   12  10.9   6.0   22.6  72.6     4.7      M    M
  9500    9.3  48.7   285   22   11  10.2   5.6   22.6  72.8     4.8      M    M
  9250   10.0  50.0   285   21   11   8.5   4.6   22.6  72.7     4.8      M    M
  9000   10.6  51.1   285   20   10   8.4   4.6   22.5  72.5     4.6      M    M
  8750   11.2  52.2   290   19   10   9.3   5.1   22.4  72.4     4.6      M    M
  8500   11.9  53.4   290   17    9   8.8   4.8   22.4  72.3     4.5      M    M
  8250   12.5  54.5   295   16    8   8.4   4.6   22.3  72.1     4.4      M    M
  8000   13.1  55.6   295   15    8   8.2   4.5   22.2  71.9     4.3      M    M
  7750   13.7  56.7   295   14    7   7.6   4.2   22.0  71.7     4.2      M    M
  7500   14.3  57.7   295   12    6   8.3   4.6   21.9  71.4     4.0      M    M
  7250   14.9  58.8   300   11    6   9.1   5.0   21.8  71.3     4.0      M    M
  7000   15.6  60.1   300   10    5   9.0   4.9   21.8  71.2     3.9      M    M
  6750   16.2  61.2   305    9    4   6.7   3.7   21.7  71.0     3.8      M    M
  6500   16.6  61.9   305    8    4   1.2   0.7   21.2  70.2     3.4      M    M
  6250   16.4  61.5   295    7    4  -3.8  -2.1   20.4  68.7     2.6      M    M
  6000   16.3  61.3   290    6    3   5.2   2.9   19.5  67.2     1.7      M    M
  5750   16.7  62.1   285    6    3  -6.3  -3.5   19.2  66.5     1.4      M    M
  5500   14.3  57.7   260    4    2 -53.1 -29.2   16.3  61.3    -1.7     32  0.2

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

           09/11/2014 at 0900 MDT          |       09/11/2014 at 1200 MDT
                                           |
K index... +5.2  LI... +2.0                | K index... +6.6  LI... +2.8
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -1.1
                                           |
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 -64.0 -83.2  270  54 28   3.2   1.8 | -64.7 -84.5  265  52 27   3.8   2.1
 45000 -59.3 -74.7  270  79 41   2.6   1.4 | -59.0 -74.2  270  77 39   3.9   2.1
 40000 -55.1 -67.2  265  74 38   5.3   2.9 | -52.9 -63.2  265  73 37   3.6   2.0
 38000 -51.8 -61.2  265  69 36   5.4   3.0 | -50.7 -59.3  265  69 36   3.6   2.0
 36000 -48.6 -55.5  265  65 33   5.4   3.0 | -48.5 -55.3  260  66 34   3.6   2.0
 34000 -44.2 -47.6  265  60 31   8.1   4.5 | -44.6 -48.3  260  63 32   8.0   4.4
 32000 -39.4 -38.9  265  56 29   8.1   4.5 | -39.9 -39.8  260  60 31   8.0   4.4
 30000 -34.2 -29.6  265  51 26   8.8   4.8 | -34.7 -30.5  260  56 29   8.9   4.9
 29000 -31.6 -24.9  270  49 25   8.8   4.8 | -31.4 -24.5  260  53 27   8.9   4.9
 28000 -28.3 -18.9  270  46 24   8.5   4.7 | -28.8 -19.8  265  51 26   8.7   4.8
 27000 -26.0 -14.8  270  45 23   7.3   4.0 | -26.4 -15.5  265  49 25   7.7   4.2
 26000 -23.9 -11.0  275  44 23   7.3   4.0 | -24.1 -11.4  265  48 25   7.7   4.3
 25000 -21.7  -7.1  275  44 23   7.4   4.0 | -21.8  -7.2  270  47 24   7.8   4.3
 24000 -19.7  -3.5  275  42 21   6.4   3.5 | -19.7  -3.5  270  45 23   6.4   3.5
 23000 -17.8  -0.0  275  39 20   6.4   3.5 | -17.8  -0.0  270  42 21   6.4   3.5
 22000 -15.9   3.4  275  36 18   6.4   3.5 | -15.9   3.4  270  39 20   6.4   3.5
 21000 -14.0   6.8  275  34 18   6.5   3.5 | -13.9   7.0  270  37 19   6.8   3.7
 20000 -12.0  10.4  275  33 17   6.5   3.5 | -11.9  10.6  270  35 18   6.8   3.7
 19500 -11.1  12.0  275  32 16   6.5   3.6 | -10.9  12.4  270  34 18   6.8   3.7
 19000 -10.1  13.8  275  31 16   7.1   3.9 |  -9.9  14.2  265  34 17   6.8   3.8
 18500  -9.0  15.8  275  32 16   7.6   4.2 |  -8.8  16.2  265  33 17   6.9   3.8
 18000  -7.8  18.0  275  32 17   7.7   4.2 |  -7.8  18.0  265  33 17   6.9   3.8
 17500  -6.8  19.8  275  32 17   6.2   3.4 |  -6.8  19.8  265  32 17   6.8   3.7
 17000  -5.9  21.4  275  31 16   6.4   3.5 |  -5.8  21.6  265  32 17   6.8   3.7
 16500  -4.9  23.2  275  31 16   7.1   3.9 |  -4.8  23.4  265  32 17   6.6   3.6
 16000  -3.8  25.2  280  31 16   7.5   4.1 |  -3.8  25.2  270  33 17   6.4   3.5
 15500  -2.7  27.1  280  31 16   7.2   4.0 |  -2.9  26.8  270  34 17   6.3   3.4
 15000  -1.8  28.8  280  31 16   5.6   3.1 |  -2.1  28.2  275  34 18   5.4   3.0
 14500  -0.5  31.1  285  31 16   5.7   3.2 |  -0.9  30.4  275  36 18   5.8   3.2
 14000   0.3  32.5  285  31 16   5.8   3.2 |  -0.0  32.0  275  35 18   6.2   3.4
 13500   1.2  34.2  285  31 16   5.8   3.2 |   0.8  33.4  275  34 17   6.4   3.5
 13000   2.0  35.6  285  31 16   5.9   3.2 |   1.8  35.2  275  31 16   6.6   3.6
 12500   2.9  37.2  285  30 16   5.9   3.3 |   2.7  36.9  275  28 14   6.8   3.7
 12000   3.7  38.7  285  29 15   6.3   3.5 |   3.7  38.7  270  24 13   7.7   4.3
 11500   4.6  40.3  285  28 14   6.4   3.5 |   4.8  40.6  265  21 11   7.6   4.1
 11000   5.5  41.9  285  25 13   7.1   3.9 |   5.6  42.1  260  17  9   4.8   2.6
 10500   6.5  43.7  285  22 11   5.7   3.2 |   6.3  43.3  250  14  7   4.1   2.3
 10250   6.8  44.2  280  21 11   3.9   2.2 |   6.5  43.7  245  13  7   2.5   1.4
 10000   7.2  45.0  280  20 10   7.2   3.9 |   6.8  44.2  240  12  6   5.4   2.9
  9750   7.7  45.9  280  17  9   9.1   5.0 |   7.2  45.0  230  11  6   7.6   4.2
  9500   8.3  46.9  275  15  8   8.1   4.5 |   7.7  45.9  220  10  5   6.4   3.5
  9250   8.8  47.8  275  13  7   6.1   3.4 |   8.1  46.6  215   9  5   5.4   2.9
  9000   9.2  48.6  280  12  6   7.0   3.8 |   8.4  47.1  215   8  4   3.5   1.9
  8750   9.8  49.6  280  11  5   8.8   4.9 |   8.6  47.5  215   6  3   3.1   1.7
  8500  10.4  50.7  285   9  5   7.8   4.3 |   8.8  47.8  215   3  2   1.1   0.6
  8250  11.0  51.8  290   8  4   7.2   4.0 |   8.7  47.7  120   1  1  -2.4  -1.3
  8000  11.5  52.7  300   7  4   6.8   3.7 |   8.5  47.3  070   5  2  -1.8  -1.0
  7750  11.9  53.4  310   6  3   6.2   3.4 |   8.4  47.1  060   8  4  -0.9  -0.5
  7500  12.4  54.3  325   6  3   5.7   3.1 |   8.4  47.1  055  11  6   5.9   3.2
  7250  12.8  55.0  350   6  3   5.4   2.9 |   9.1  48.4  055  11  6  11.1   6.1
  7000  13.2  55.8  010   8  4   5.6   3.1 |   9.9  49.8  055  12  6   9.9   5.4
  6750  13.5  56.3  020   9  5   4.2   2.3 |  10.6  51.1  055  12  6  10.7   5.9
  6500  13.7  56.7  030  10  5   1.3   0.7 |  11.4  52.5  055  12  6  10.5   5.8
  6250  13.8  56.8  030  10  5   1.6   0.9 |  12.2  54.0  050  12  6  10.0   5.5
  6000  13.8  56.8  035   9  5  -2.0  -1.1 |  13.0  55.4  050  12  6  11.0   6.0
  5750  13.6  56.5  035   7  4   4.1   2.2 |  14.0  57.2  050  12  6  17.2   9.4
  5500  14.6  58.3  035   7  3  25.4  13.9 |  15.5  59.9  050  11  6  24.6  13.5

           09/11/2014 at 1500 MDT          |       09/11/2014 at 1800 MDT
                                           |
K index... +21.8  LI... -0.2               | K index... +18.6  LI... +0.4
CAPE... 0.0  CIN... -51.1                  | CAPE... +3.5  CIN... -2.5
                                           |
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 -64.8 -84.6  265  55 28   3.8   2.1 | -65.5 -85.9  270  58 30   4.4   2.4
 45000 -59.0 -74.2  270  76 39   4.3   2.4 | -58.8 -73.8  270  74 38   4.6   2.5
 40000 -52.2 -62.0  265  73 38   3.6   2.0 | -51.5 -60.7  265  71 36   4.2   2.3
 38000 -50.0 -58.0  265  70 36   3.5   1.9 | -49.0 -56.2  265  69 36   4.2   2.3
 36000 -47.9 -54.2  260  67 34   3.5   1.9 | -46.5 -51.7  265  68 35   4.2   2.3
 34000 -44.3 -47.7  260  65 33   7.5   4.1 | -43.1 -45.6  265  65 34   6.3   3.5
 32000 -39.8 -39.6  255  63 32   7.5   4.1 | -39.3 -38.7  265  63 32   6.3   3.5
 30000 -34.9 -30.8  255  60 31   8.6   4.7 | -35.1 -31.2  265  61 31   7.5   4.1
 29000 -31.7 -25.1  260  58 30   8.6   4.7 | -32.3 -26.1  270  60 31   7.5   4.1
 28000 -29.1 -20.4  260  57 29   8.5   4.7 | -30.1 -22.2  270  59 30   7.5   4.1
 27000 -26.8 -16.2  265  55 28   7.5   4.1 | -27.7 -17.9  270  58 30   7.9   4.3
 26000 -24.6 -12.3  265  54 28   7.5   4.1 | -25.4 -13.7  270  57 29   7.9   4.3
 25000 -22.3  -8.1  265  52 27   7.6   4.2 | -23.0  -9.4  275  56 29   7.9   4.3
 24000 -20.3  -4.5  270  51 26   6.2   3.4 | -21.0  -5.8  275  54 28   6.2   3.4
 23000 -18.5  -1.3  270  49 25   6.2   3.4 | -19.2  -2.6  270  53 27   6.2   3.4
 22000 -16.6   2.1  270  48 25   6.3   3.5 | -17.3   0.9  270  51 26   6.2   3.4
 21000 -14.9   5.2  270  47 24   5.7   3.1 | -15.6   3.9  270  49 25   5.8   3.2
 20000 -13.2   8.2  270  47 24   5.7   3.1 | -13.9   7.0  265  48 25   5.9   3.2
 19500 -12.4   9.7  270  47 24   5.7   3.1 | -13.0   8.6  265  48 24   6.0   3.3
 19000 -11.5  11.3  270  47 24   5.8   3.2 | -12.2  10.0  260  47 24   7.5   4.1
 18500 -10.7  12.7  270  46 24   5.9   3.3 | -10.9  12.4  260  45 23   9.0   4.9
 18000  -9.8  14.4  265  45 23   5.8   3.2 |  -9.6  14.7  255  44 22   9.2   5.1
 17500  -8.9  16.0  265  43 22   7.6   4.2 |  -8.3  17.1  255  42 22   8.9   4.9
 17000  -7.8  18.0  260  41 21   7.5   4.1 |  -7.0  19.4  255  40 20   9.0   4.9
 16500  -6.8  19.8  260  39 20   8.2   4.5 |  -5.7  21.7  250  38 19   9.0   4.9
 16000  -5.5  22.1  255  36 19   8.7   4.8 |  -4.4  24.1  250  36 19   9.0   4.9
 15500  -4.3  24.3  255  34 17   8.7   4.8 |  -3.1  26.4  250  34 18   8.7   4.8
 15000  -3.0  26.6  250  31 16   8.7   4.8 |  -2.0  28.4  250  33 17   7.4   4.1
 14500  -1.1  30.0  250  28 15   8.4   4.6 |  -0.4  31.3  245  31 16   6.4   3.5
 14000   0.1  32.2  250  27 14   8.1   4.4 |   0.3  32.5  240  30 15   5.3   2.9
 13500   1.3  34.3  245  25 13   7.7   4.2 |   1.1  34.0  235  29 15   4.6   2.5
 13000   2.3  36.1  245  24 12   6.5   3.5 |   1.5  34.7  230  28 14   2.5   1.4
 12500   3.2  37.8  240  23 12   6.4   3.5 |   1.8  35.2  225  27 14   2.3   1.3
 12000   3.9  39.0  235  22 11   4.8   2.6 |   1.8  35.2  225  25 13  -0.8  -0.4
 11500   4.6  40.3  230  21 11   4.7   2.6 |   1.7  35.1  220  23 12  -0.6  -0.3
 11000   4.8  40.6  225  19 10  -0.1  -0.1 |   1.6  34.9  225  19 10  -1.1  -0.6
 10500   4.7  40.5  220  16  8   0.2   0.1 |   1.5  34.7  230  15  8  -1.1  -0.6
 10250   4.7  40.5  220  14  7  -1.6  -0.9 |   1.4  34.5  235  13  7  -1.1  -0.6
 10000   4.5  40.1  220  12  6  -3.6  -2.0 |   1.4  34.5  240  11  6  -0.6  -0.3
  9750   4.2  39.6  215   6  3  -4.4  -2.4 |   1.3  34.3  240   6  3  -0.3  -0.2
  9500   3.9  39.0  160   2  1  -2.6  -1.4 |   1.3  34.3  235   2  1   0.2   0.1
  9250   3.8  38.8  065   4  2   0.5   0.3 |   1.4  34.5  050   1  1   1.4   0.8
  9000   4.0  39.2  055   7  4   4.9   2.7 |   1.5  34.7  045   4  2   2.1   1.1
  8750   4.5  40.1  050   9  5   7.8   4.3 |   1.7  35.1  045   8  4   2.3   1.3
  8500   5.0  41.0  050  12  6   8.2   4.5 |   1.9  35.4  045  12  6   3.3   1.8
  8250   5.7  42.3  045  12  6   8.9   4.9 |   2.2  36.0  040  14  7   4.1   2.3
  8000   6.4  43.5  045  13  6   9.5   5.2 |   2.5  36.5  040  16  8   4.1   2.3
  7750   7.1  44.8  045  13  7  11.1   6.1 |   2.8  37.0  040  18  9   6.8   3.7
  7500   8.0  46.4  045  13  7  10.6   5.8 |   3.5  38.3  035  19 10   9.4   5.2
  7250   8.7  47.7  045  13  7   9.8   5.4 |   4.2  39.6  035  19 10   9.8   5.4
  7000   9.4  48.9  045  13  7   9.8   5.4 |   4.9  40.8  035  19 10   9.3   5.1
  6750  10.2  50.4  045  13  7   9.8   5.4 |   5.6  42.1  035  19 10   9.7   5.3
  6500  10.9  51.6  045  13  7  10.4   5.7 |   6.3  43.3  035  19 10  10.5   5.7
  6250  11.7  53.1  045  13  7  10.6   5.8 |   7.1  44.8  035  18 10  10.5   5.8
  6000  12.5  54.5  045  13  7  10.7   5.8 |   7.9  46.2  035  18  9  10.0   5.5
  5750  13.4  56.1  045  13  6  16.6   9.1 |   8.7  47.7  035  17  9  12.1   6.6
  5500  15.0  59.0  045  13  6  25.8  14.1 |   9.7  49.5  035  16  8  17.0   9.3
________________________________________________________________________________

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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