Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 230147
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1947 MDT Tuesday, April 22, 2014

This forecast is for Wednesday, April 23, 2014:

If the trigger temperature of 67.2 F/19.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7299 ft MSL (2012 ft AGL)

Forecast maximum temperature................... 65.0 F/18.8 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 1200 MDT
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................. 6084 ft MSL (796 ft AGL)
Thermal soaring outlook for Thursday 04/24..... Good

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 39438 ft MSL (34151 ft AGL)
Wave soaring outlook for Thursday 04/24........ Fair

Remarks...

Sunrise/Sunset.................... 06:10:29 / 19:44:49 MDT
Total possible sunshine........... 13 hr 34 min 19 sec (814 min 19 sec)
Altitude of sun at 12:57:49 MDT... 62.92 degrees

Upper air data from numerical model forecast valid on 04/23/2014 at 0600 MDT

Freezing level.................. 12218 ft MSL (6931 ft AGL)
Convective condensation level... 16148 ft MSL (10861 ft AGL)
Lifted condensation level....... 14157 ft MSL (8870 ft AGL)
Lifted index.................... +3.0
K index......................... +10.5

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  -61.5 -78.7   240   33   17  -1.4  -0.8      M     M       M      M    M
 45000  -63.6 -82.5   230   60   31  -1.2  -0.6      M     M       M      M    M
 40000  -60.7 -77.3   220   69   35   1.9   1.1      M     M       M      M    M
 38000  -58.2 -72.8   215   70   36   5.8   3.2      M     M       M      M    M
 36000  -54.7 -66.5   215   69   36   5.8   3.2      M     M       M      M    M
 34000  -51.0 -59.8   210   68   35   7.7   4.2      M     M       M      M    M
 32000  -46.4 -51.5   215   65   33   7.7   4.2      M     M       M      M    M
 30000  -41.7 -43.1   215   62   32   8.0   4.4   34.2  93.6    11.9      M    M
 29000  -39.3 -38.7   215   61   31   8.1   4.4   33.5  92.2    11.5      M    M
 28000  -36.2 -33.2   215   59   31   8.1   4.4   32.7  90.9    11.1      M    M
 27000  -33.8 -28.8   215   59   30   8.1   4.4   32.2  89.9    10.8      M    M
 26000  -31.4 -24.5   215   58   30   8.0   4.4   31.4  88.6    10.3      M    M
 25000  -29.0 -20.2   220   57   29   8.0   4.4   30.8  87.4    10.0      M    M
 24000  -26.6 -15.9   220   56   29   7.7   4.2   30.3  86.5     9.6      M    M
 23000  -24.4 -11.9   220   56   29   7.4   4.0   29.3  84.8     9.0      M    M
 22000  -22.2  -8.0   220   55   29   7.4   4.1   28.5  83.2     8.3      M    M
 21000  -20.0  -4.0   220   55   28   7.3   4.0   27.7  81.8     7.8      M    M
 20000  -17.9  -0.2   225   55   28   7.3   4.0   26.7  80.1     7.0      M    M
 19500  -16.8   1.8   225   55   28   7.3   4.0   26.3  79.3     6.7      M    M
 19000  -15.7   3.7   225   55   28   7.3   4.0   25.9  78.6     6.3      M    M
 18500  -14.6   5.7   225   55   28   7.5   4.1   25.5  77.9     6.0      M    M
 18000  -13.5   7.7   225   55   28   7.8   4.3   25.1  77.3     5.7      M    M
 17500  -12.3   9.9   230   55   28   7.8   4.3   24.8  76.7     5.5      M    M
 17000  -11.2  11.8   230   55   28   7.7   4.3   24.5  76.0     5.2      M    M
 16500  -10.0  14.0   230   55   28   7.8   4.3   24.1  75.4     4.9      M    M
 16000   -8.9  16.0   235   55   28   7.7   4.2   23.8  74.8     4.7      M    M
 15500   -7.7  18.1   235   53   27   7.7   4.2   23.4  74.2     4.4      M    M
 15000   -6.6  20.1   240   51   26   7.6   4.2   23.1  73.6     4.1      M    M
 14500   -5.0  23.0   240   45   23   7.2   3.9   22.5  72.5     3.5      M    M
 14000   -3.9  25.0   240   41   21   7.3   4.0   22.1  71.7     3.2      M    M
 13500   -2.8  27.0   240   37   19   7.5   4.1   21.7  71.0     2.8      M    M
 13000   -1.7  28.9   245   34   17   7.8   4.3   21.3  70.4     2.4      M    M
 12500   -0.5  31.1   245   32   16   8.5   4.7   21.1  70.0     2.2      M    M
 12000    0.8  33.4   250   30   15   8.3   4.6   20.9  69.6     2.0      M    M
 11500    1.9  35.4   250   28   14   7.4   4.0   20.6  69.0     1.7      M    M
 11000    2.9  37.2   255   25   13   7.7   4.2   20.2  68.3     1.3      M    M
 10500    4.2  39.6   255   23   12   8.9   4.9   20.0  68.1     1.1      M    M
 10250    4.9  40.8   255   23   12  10.3   5.6   20.0  68.0     1.1      M    M
 10000    5.7  42.3   255   22   11  11.2   6.2   20.1  68.2     1.2      M    M
  9750    6.5  43.7   255   21   11   9.7   5.3   20.2  68.3     1.2      M    M
  9500    7.2  45.0   255   20   10   9.6   5.2   20.1  68.2     1.2      M    M
  9250    7.9  46.2   260   19   10   9.2   5.1   20.1  68.2     1.2      M    M
  9000    8.5  47.3   260   18    9   7.9   4.3   20.0  68.1     1.1      M    M
  8750    9.1  48.4   260   17    9   7.9   4.3   19.9  67.8     0.9      M    M
  8500    9.7  49.5   260   17    9   8.5   4.7   19.7  67.5     0.8      M    M
  8250   10.3  50.5   255   16    8   8.2   4.5   19.6  67.4     0.7      M    M
  8000   10.9  51.6   255   16    8   8.8   4.8   19.5  67.2     0.6      M    M
  7750   11.6  52.9   255   15    8   7.4   4.1   19.4  67.0     0.5      M    M
  7500   12.0  53.6   255   15    8   5.8   3.2   19.2  66.5     0.2      M    M
  7250   12.5  54.5   250   14    7   6.3   3.5   18.9  66.0    -0.1     74  0.4
  7000   12.9  55.2   250   14    7   6.1   3.3   18.6  65.5    -0.3     53  0.3
  6750   13.3  55.9   250   14    7   3.2   1.8   18.3  64.9    -0.7     35  0.2
  6500   13.5  56.3   250   13    7   3.9   2.1   17.7  63.9    -1.3     22  0.1
  6250   13.7  56.7   250   13    7  -3.3  -1.8   17.2  62.9    -1.8      9  0.0
  6000   12.8  55.0   240   13    7 -14.8  -8.1   15.6  60.2    -3.4     27  0.1
  5750   11.5  52.7   235   12    6 -20.1 -11.0   13.6  56.5    -5.5     59  0.3
  5500    9.5  49.1   225    9    5 -30.4 -16.7   11.0  51.9    -8.2    111  0.6

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

           04/23/2014 at 0900 MDT          |       04/23/2014 at 1200 MDT
                                           |
K index... +6.6  LI... +2.5                | K index... +10.1  LI... +2.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -1.5
                                           |
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 -58.9 -74.0  245  34 17  -1.1  -0.6 | -59.3 -74.7  240  35 18  -1.7  -1.0
 45000 -60.5 -76.9  240  65 34  -1.3  -0.7 | -61.9 -79.4  235  68 35  -2.1  -1.2
 40000 -59.3 -74.7  225  66 34   0.8   0.5 | -59.1 -74.4  235  76 39   1.9   1.1
 38000 -57.6 -71.7  220  68 35   4.7   2.6 | -57.5 -71.5  230  74 38   3.7   2.0
 36000 -54.8 -66.6  215  70 36   4.7   2.6 | -55.2 -67.4  230  68 35   3.7   2.0
 34000 -51.8 -61.2  215  72 37   7.5   4.1 | -52.6 -62.7  225  62 32   8.4   4.6
 32000 -47.4 -53.3  215  71 36   7.3   4.0 | -47.8 -54.0  230  61 32   8.0   4.4
 30000 -43.0 -45.4  215  69 36   7.8   4.3 | -43.1 -45.6  230  61 31   7.4   4.1
 29000 -40.1 -40.2  215  67 34   7.8   4.3 | -40.9 -41.6  235  58 30   7.5   4.1
 28000 -37.7 -35.9  215  65 33   7.8   4.3 | -38.1 -36.6  235  55 28   7.5   4.1
 27000 -35.4 -31.7  215  63 32   8.0   4.4 | -35.8 -32.4  235  53 27   7.8   4.3
 26000 -32.9 -27.2  215  61 32   8.2   4.5 | -33.4 -28.1  235  52 27   8.1   4.5
 25000 -30.5 -22.9  215  60 31   8.2   4.5 | -31.0 -23.8  230  51 26   8.1   4.5
 24000 -28.0 -18.4  215  58 30   8.1   4.5 | -28.5 -19.3  230  50 26   8.1   4.4
 23000 -25.7 -14.3  220  57 29   7.8   4.3 | -26.1 -15.0  230  48 25   8.0   4.4
 22000 -23.4 -10.1  220  56 29   7.8   4.3 | -23.7 -10.7  230  47 24   8.0   4.4
 21000 -21.1  -6.0  220  54 28   7.4   4.1 | -21.3  -6.3  230  45 23   7.6   4.2
 20000 -18.9  -2.0  225  52 27   7.2   3.9 | -19.1  -2.4  230  45 23   7.3   4.0
 19500 -17.9  -0.2  225  51 26   7.2   3.9 | -18.1  -0.6  230  45 23   7.3   4.0
 19000 -16.8   1.8  225  50 26   7.2   3.9 | -17.0   1.4  230  44 23   7.3   4.0
 18500 -15.7   3.7  225  49 25   7.3   4.0 | -15.9   3.4  230  44 23   7.2   3.9
 18000 -14.6   5.7  230  48 25   7.8   4.3 | -14.9   5.2  235  43 22   6.6   3.6
 17500 -13.4   7.9  230  47 24   7.8   4.3 | -13.9   7.0  235  43 22   6.7   3.7
 17000 -12.3   9.9  230  46 24   7.3   4.0 | -13.0   8.6  235  42 22   5.6   3.1
 16500 -11.2  11.8  235  45 23   7.3   4.0 | -12.2  10.0  235  41 21   5.5   3.0
 16000 -10.1  13.8  235  44 22   7.0   3.8 | -11.3  11.7  240  39 20   4.9   2.7
 15500  -9.1  15.6  235  42 22   6.7   3.7 | -10.8  12.6  240  37 19   4.2   2.3
 15000  -8.2  17.2  240  40 21   6.7   3.7 | -10.2  13.6  240  35 18   4.4   2.4
 14500  -6.7  19.9  240  36 19   6.9   3.8 |  -9.4  15.1  240  32 16   6.3   3.5
 14000  -5.7  21.7  240  34 17   7.0   3.9 |  -8.1  17.4  240  27 14   7.2   4.0
 13500  -4.6  23.7  240  32 16   7.2   4.0 |  -6.9  19.6  240  23 12   8.3   4.5
 13000  -3.6  25.5  240  30 15   7.4   4.1 |  -5.7  21.7  235  20 10   8.5   4.7
 12500  -2.4  27.7  245  29 15   8.0   4.4 |  -4.4  24.1  235  16  8   8.9   4.9
 12000  -1.3  29.7  250  29 15   7.9   4.3 |  -3.1  26.4  230  13  7   9.0   4.9
 11500  -0.2  31.6  255  27 14   7.3   4.0 |  -1.8  28.8  235  10  5   9.1   5.0
 11000   0.9  33.6  255  25 13   7.3   4.0 |  -0.4  31.3  240   8  4   9.1   5.0
 10500   2.0  35.6  255  22 11   7.2   3.9 |   0.9  33.6  250   7  3   8.9   4.9
 10250   2.5  36.5  255  21 11   7.9   4.3 |   1.6  34.9  255   6  3  10.1   5.5
 10000   3.1  37.6  260  20 10   8.9   4.9 |   2.4  36.3  255   6  3  11.0   6.1
  9750   3.8  38.8  260  19 10   8.8   4.8 |   3.2  37.8  260   6  3  10.2   5.6
  9500   4.4  39.9  260  17  9   8.8   4.8 |   4.0  39.2  260   6  3  10.2   5.6
  9250   5.1  41.2  260  16  8   8.7   4.8 |   4.7  40.5  265   6  3   9.8   5.4
  9000   5.7  42.3  260  14  7   8.2   4.5 |   5.4  41.7  265   6  3   9.2   5.0
  8750   6.3  43.3  260  13  7   8.1   4.5 |   6.1  43.0  270   6  3   9.7   5.3
  8500   6.9  44.4  260  12  6   8.6   4.7 |   6.9  44.4  270   6  3   9.9   5.5
  8250   7.5  45.5  260  11  6   8.1   4.4 |   7.6  45.7  275   6  3  10.3   5.6
  8000   8.2  46.8  260  10  5   9.6   5.3 |   8.4  47.1  275   6  3  11.5   6.3
  7750   8.9  48.0  260   9  5   9.5   5.2 |   9.3  48.7  275   6  3  10.2   5.6
  7500   9.5  49.1  260   8  4   8.0   4.4 |   9.9  49.8  280   6  3   8.6   4.7
  7250  10.1  50.2  255   7  4   8.4   4.6 |  10.6  51.1  280   6  3   9.3   5.1
  7000  10.8  51.4  255   7  3   8.3   4.5 |  11.3  52.3  280   6  3  10.0   5.5
  6750  11.4  52.5  260   6  3   7.4   4.1 |  12.1  53.8  285   6  3  10.1   5.6
  6500  11.9  53.4  255   6  3   7.5   4.1 |  12.8  55.0  285   6  3   9.8   5.4
  6250  12.4  54.3  250   7  3   5.5   3.0 |  13.5  56.3  285   6  3  10.4   5.7
  6000  12.6  54.7  245   6  3   2.9   1.6 |  14.4  57.9  290   6  3  11.4   6.2
  5750  12.8  55.0  240   6  3   5.1   2.8 |  15.2  59.4  290   6  3  11.1   6.1
  5500  13.4  56.1  240   5  2  11.0   6.0 |  16.2  61.2  295   6  3  16.9   9.2

           04/23/2014 at 1500 MDT          |       04/23/2014 at 1800 MDT
                                           |
K index... +15.9  LI... +2.4               | K index... +13.9  LI... +2.3
CAPE... 0.0  CIN... -2.3                   | CAPE... 0.0  CIN... -0.1
                                           |
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 -58.2 -72.8  245  30 16  -0.3  -0.2 | -57.6 -71.7  245  33 17  -0.5  -0.3
 45000 -58.6 -73.5  240  62 32  -0.1  -0.1 | -58.3 -72.9  255  53 27  -0.7  -0.4
 40000 -57.8 -72.0  230  79 40   0.6   0.3 | -56.0 -68.8  235  61 32   1.6   0.9
 38000 -56.9 -70.4  230  82 42   2.7   1.5 | -55.2 -67.4  230  66 34   0.8   0.5
 36000 -55.3 -67.5  225  80 41   2.7   1.5 | -54.7 -66.5  225  70 36   0.8   0.5
 34000 -53.4 -64.1  225  78 40   6.7   3.7 | -54.1 -65.4  220  75 39   4.9   2.7
 32000 -49.2 -56.6  230  73 38   7.0   3.8 | -50.3 -58.5  225  68 35   6.3   3.5
 30000 -44.4 -47.9  235  67 34   7.9   4.3 | -46.4 -51.5  225  62 32   8.7   4.8
 29000 -42.0 -43.6  230  64 33   7.9   4.3 | -43.0 -45.4  225  59 30   9.0   4.9
 28000 -39.7 -39.5  230  60 31   7.9   4.4 | -40.3 -40.5  225  56 29   9.0   4.9
 27000 -37.3 -35.1  230  57 29   8.3   4.5 | -37.6 -35.7  220  54 28   8.6   4.7
 26000 -34.7 -30.5  230  55 28   8.8   4.8 | -35.3 -31.5  220  52 27   7.6   4.2
 25000 -32.0 -25.6  230  52 27   8.8   4.8 | -33.1 -27.6  220  50 26   7.6   4.2
 24000 -29.4 -20.9  225  50 26   8.8   4.8 | -30.8 -23.4  215  48 25   7.6   4.2
 23000 -26.9 -16.4  225  48 25   8.1   4.4 | -28.4 -19.1  215  47 24   8.1   4.4
 22000 -24.5 -12.1  225  47 24   8.1   4.4 | -26.0 -14.8  210  45 23   8.1   4.4
 21000 -22.0  -7.6  225  45 23   7.7   4.2 | -23.6 -10.5  205  44 22   7.6   4.2
 20000 -19.9  -3.8  225  43 22   7.1   3.9 | -21.5  -6.7  210  43 22   6.9   3.8
 19500 -18.8  -1.8  225  41 21   7.1   3.9 | -20.5  -4.9  210  43 22   6.9   3.8
 19000 -17.8  -0.0  225  40 21   7.1   3.9 | -19.5  -3.1  210  43 22   6.9   3.8
 18500 -16.7   1.9  225  39 20   6.8   3.7 | -18.5  -1.3  215  42 22   7.0   3.8
 18000 -15.9   3.4  225  37 19   4.9   2.7 | -17.4   0.7  215  42 22   7.6   4.2
 17500 -15.1   4.8  225  36 19   5.0   2.7 | -16.3   2.7  215  42 22   7.6   4.2
 17000 -14.4   6.1  225  34 18   4.7   2.6 | -15.2   4.6  215  42 21   6.9   3.8
 16500 -13.8   7.2  225  32 16   4.7   2.6 | -14.2   6.4  220  41 21   6.8   3.7
 16000 -13.1   8.4  220  29 15   5.0   2.7 | -13.2   8.2  225  41 21   6.8   3.7
 15500 -12.4   9.7  220  26 13   5.4   3.0 | -12.2  10.0  225  38 19   6.7   3.7
 15000 -11.2  11.8  215  20 11   7.1   3.9 | -11.2  11.8  230  35 18   6.7   3.7
 14500 -10.0  14.0  210  18  9   7.7   4.3 |  -9.7  14.5  230  30 15   7.0   3.8
 14000  -8.9  16.0  210  15  8   8.4   4.6 |  -8.6  16.5  235  26 14   7.1   3.9
 13500  -7.6  18.3  215  14  7   9.1   5.0 |  -7.6  18.3  235  24 12   7.3   4.0
 13000  -6.2  20.8  215  12  6   9.2   5.0 |  -6.5  20.3  240  21 11   7.5   4.1
 12500  -4.8  23.4  225  11  5   9.4   5.2 |  -5.4  22.3  245  20 10   8.2   4.5
 12000  -3.5  25.7  230   9  5   9.4   5.2 |  -4.2  24.4  250  19 10   8.2   4.5
 11500  -2.0  28.4  245   8  4   9.5   5.2 |  -2.9  26.8  260  19 10   8.3   4.6
 11000  -0.6  30.9  260   8  4   9.4   5.1 |  -1.7  28.9  270  19 10   8.2   4.5
 10500   0.7  33.3  275   9  4   8.9   4.9 |  -0.5  31.1  275  20 10   7.4   4.1
 10250   1.4  34.5  285   9  5   9.7   5.3 |   0.0  32.0  280  20 10   8.0   4.4
 10000   2.2  36.0  290   9  5  10.6   5.8 |   0.7  33.3  285  21 11   8.7   4.8
  9750   3.0  37.4  295  10  5  10.3   5.6 |   1.3  34.3  290  22 11   8.4   4.6
  9500   3.7  38.7  300  10  5  10.2   5.6 |   1.9  35.4  295  22 11   8.2   4.5
  9250   4.5  40.1  300  10  5  10.2   5.6 |   2.5  36.5  300  23 12   8.3   4.6
  9000   5.2  41.4  305  11  6   9.7   5.3 |   3.1  37.6  300  24 12   8.0   4.4
  8750   5.9  42.6  305  11  6   9.5   5.2 |   3.7  38.7  305  24 12   8.2   4.5
  8500   6.6  43.9  305  11  6   9.6   5.2 |   4.4  39.9  310  24 12   8.4   4.6
  8250   7.4  45.3  305  12  6  10.0   5.5 |   5.0  41.0  315  24 13   8.6   4.7
  8000   8.2  46.8  310  12  6  11.2   6.2 |   5.7  42.3  315  25 13  10.0   5.5
  7750   9.0  48.2  310  12  6  10.2   5.6 |   6.4  43.5  320  25 13   9.9   5.4
  7500   9.7  49.5  310  12  6   8.7   4.8 |   7.1  44.8  320  25 13   8.9   4.9
  7250  10.3  50.5  310  12  6   9.7   5.3 |   7.8  46.0  320  24 13   9.7   5.3
  7000  11.1  52.0  315  13  6  10.8   5.9 |   8.6  47.5  320  24 13  10.6   5.8
  6750  11.9  53.4  315  13  7  10.4   5.7 |   9.4  48.9  320  24 12   9.9   5.4
  6500  12.7  54.9  315  13  7   9.7   5.3 |  10.1  50.2  320  24 12   9.1   5.0
  6250  13.4  56.1  315  13  7  10.5   5.8 |  10.8  51.4  325  24 12  10.7   5.9
  6000  14.2  57.6  315  13  7  11.5   6.3 |  11.6  52.9  325  23 12  12.0   6.6
  5750  15.1  59.2  315  13  7  11.0   6.1 |  12.5  54.5  325  22 11  10.4   5.7
  5500  16.0  60.8  315  12  6  16.5   9.0 |  13.2  55.8  325  20 10  11.4   6.3
________________________________________________________________________________

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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