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396
UXUS97 KBOU 260014
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1814 MDT Saturday, October 25, 2014

This forecast is for Sunday, October 26, 2014:

If the trigger temperature of 70.2 F/21.2 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 340 ft/min (1.7 m/s)
   Maximum height of thermals.................. 12512 ft MSL (7225 ft AGL)

Forecast maximum temperature................... 78.0 F/26.0 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9820 ft MSL (4533 ft AGL)
Thermal soaring outlook for Monday 10/27....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Slight improvement.
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 18827 ft MSL (13540 ft AGL)
Wave soaring outlook for Monday 10/27.......... Fair

Remarks...

Sunrise/Sunset.................... 07:21:38 / 18:06:11 MDT
Total possible sunshine........... 10 hr 44 min 33 sec (644 min 33 sec)
Altitude of sun at 12:43:31 MDT... 37.66 degrees

Upper air data from numerical model forecast valid on 10/26/2014 at 0600 MDT

Freezing level.................. 14129 ft MSL (8842 ft AGL)
Convective condensation level... 16234 ft MSL (10947 ft AGL)
Lifted condensation level....... 14955 ft MSL (9668 ft AGL)
Lifted index.................... +0.5
K index......................... +3.4

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  -68.6 -91.5   245   53   27   4.0   2.2      M     M       M      M    M
 45000  -62.1 -79.8   250   70   36   5.0   2.7      M     M       M      M    M
 40000  -54.6 -66.3   250   61   31   5.0   2.8      M     M       M      M    M
 38000  -51.5 -60.7   250   57   30   5.1   2.8      M     M       M      M    M
 36000  -48.5 -55.3   255   54   28   5.1   2.8      M     M       M      M    M
 34000  -45.1 -49.2   255   51   26   5.9   3.3      M     M       M      M    M
 32000  -41.6 -42.9   250   49   25   5.9   3.3      M     M       M      M    M
 30000  -36.4 -33.5   250   47   24   9.2   5.0   38.8 101.9    10.1      M    M
 29000  -33.6 -28.5   250   47   24   9.2   5.0   38.6 101.5    10.0      M    M
 28000  -30.9 -23.6   255   48   25   9.2   5.0   38.5 101.3    10.0      M    M
 27000  -28.2 -18.8   255   45   23   8.8   4.8   38.1 100.7     9.9      M    M
 26000  -25.5 -13.9   255   42   21   8.8   4.8   37.7  99.9     9.7      M    M
 25000  -22.9  -9.2   255   38   19   8.8   4.8   37.5  99.5     9.6      M    M
 24000  -20.6  -5.1   250   35   18   5.7   3.1   36.6  98.0     9.0      M    M
 23000  -18.9  -2.0   250   33   17   5.7   3.1   35.1  95.2     7.9      M    M
 22000  -17.2   1.0   245   31   16   5.7   3.1   33.7  92.6     6.8      M    M
 21000  -15.2   4.6   245   30   15   7.4   4.1   32.6  90.6     5.9      M    M
 20000  -13.0   8.6   240   29   15   7.5   4.1   31.7  89.1     5.2      M    M
 19500  -11.9  10.6   240   29   15   7.5   4.1   31.3  88.4     4.9      M    M
 19000  -10.8  12.6   240   29   15   7.6   4.2   31.0  87.8     4.6      M    M
 18500   -9.5  14.9   235   29   15   8.8   4.8   30.7  87.3     4.4      M    M
 18000   -8.2  17.2   235   29   15   8.8   4.8   30.6  87.0     4.3      M    M
 17500   -7.0  19.4   230   29   15   8.1   4.4   30.4  86.7     4.2      M    M
 17000   -5.8  21.6   230   27   14   7.9   4.3   30.0  86.1     3.9      M    M
 16500   -4.6  23.7   225   26   13   7.5   4.1   29.7  85.5     3.6      M    M
 16000   -3.6  25.5   225   24   13   6.0   3.3   29.2  84.5     3.1      M    M
 15500   -2.3  27.9   215   22   11   6.1   3.3   28.2  82.8     2.3      M    M
 15000   -1.4  29.5   210   20   10   6.1   3.4   27.6  81.7     1.7      M    M
 14500   -0.5  31.1   210   19   10   6.3   3.5   27.0  80.6     1.2      M    M
 14000    0.5  32.9   205   17    9   8.2   4.5   26.6  80.0     0.8      M    M
 13500    1.7  35.1   205   15    8   8.1   4.5   26.4  79.5     0.5      M    M
 13000    2.9  37.2   210   12    6   8.3   4.6   26.1  79.0     0.2      M    M
 12500    4.1  39.4   230    9    5   8.4   4.6   25.9  78.6    -0.0    531  2.7
 12000    5.3  41.5   255   10    5   8.6   4.7   25.7  78.2    -0.3    480  2.4
 11500    6.5  43.7   270   14    7   8.9   4.9   25.5  77.9    -0.5    429  2.2
 11000    7.6  45.7   275   18    9   5.1   2.8   25.1  77.2    -1.0    383  1.9
 10500    8.2  46.8   280   23   12   4.5   2.5   24.3  75.8    -1.8    350  1.8
 10250    8.5  47.3   280   26   13   5.5   3.0   23.9  75.1    -2.3    333  1.7
 10000    8.8  47.8   280   29   15   4.7   2.6   23.6  74.5    -2.7    316  1.6
  9750    9.0  48.2   285   30   15   3.0   1.7   23.1  73.6    -3.2    303  1.5
  9500    9.2  48.6   285   31   16   3.7   2.0   22.6  72.7    -3.7    289  1.5
  9250    9.4  48.9   285   32   17   2.9   1.6   22.1  71.8    -4.3    275  1.4
  9000    9.6  49.3   285   32   17   3.8   2.1   21.6  70.9    -4.8    262  1.3
  8750   10.0  50.0   285   31   16   5.3   2.9   21.2  70.2    -5.2    243  1.2
  8500   10.4  50.7   285   30   15   4.5   2.5   20.8  69.5    -5.6    225  1.1
  8250   10.7  51.3   285   29   15   6.1   3.4   20.5  68.8    -5.9    207  1.0
  8000   11.3  52.3   285   26   13   7.7   4.2   20.3  68.5    -6.1    183  0.9
  7750   11.8  53.2   285   23   12   7.4   4.1   20.1  68.2    -6.3    158  0.8
  7500   12.4  54.3   285   21   11   7.5   4.1   19.9  67.9    -6.5    134  0.7
  7250   13.0  55.4   285   19   10   8.0   4.4   19.8  67.6    -6.6    109  0.6
  7000   13.6  56.5   285   17    9   7.9   4.3   19.6  67.4    -6.8     83  0.4
  6750   14.3  57.7   280   15    8   8.9   4.9   19.5  67.1    -6.9     57  0.3
  6500   14.8  58.6   280   13    7   3.8   2.1   19.4  66.9    -7.0     32  0.2
  6250   14.8  58.6   275   12    6  -3.8  -2.1   18.6  65.4    -7.9     26  0.1
  6000   14.5  58.1   265   10    5  -2.7  -1.5   17.5  63.6    -8.9     27  0.1
  5750   14.2  57.6   250    9    5  -7.7  -4.2   16.5  61.8    -9.9     28  0.1
  5500   12.8  55.0   230    9    5 -35.0 -19.2   14.4  57.9   -12.1     64  0.3

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

           10/26/2014 at 0900 MDT          |       10/26/2014 at 1200 MDT
                                           |
K index... -3.9  LI... +2.5                | K index... +1.5  LI... +2.6
CAPE... 0.0  CIN... -1.4                   | 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 -67.2 -89.0  250  60 31   2.5   1.4 | -66.0 -86.8  250  63 32   1.8   1.0
 45000 -63.0 -81.4  250  81 42   4.3   2.4 | -62.9 -81.2  250  89 46   3.9   2.2
 40000 -56.2 -69.2  250  74 38   4.5   2.5 | -56.9 -70.4  250  80 41   3.9   2.1
 38000 -53.1 -63.6  250  69 36   5.2   2.9 | -54.0 -65.2  250  75 39   5.0   2.8
 36000 -50.0 -58.0  250  64 33   5.2   2.8 | -50.9 -59.6  250  70 36   5.0   2.8
 34000 -46.2 -51.2  255  59 30   7.2   4.0 | -46.8 -52.2  250  64 33   7.3   4.0
 32000 -41.9 -43.4  255  54 28   7.3   4.0 | -42.4 -44.3  255  58 30   7.3   4.0
 30000 -37.2 -35.0  260  50 26   8.4   4.6 | -37.6 -35.7  250  53 27   8.3   4.6
 29000 -34.1 -29.4  260  47 24   8.4   4.6 | -35.1 -31.2  250  50 26   8.3   4.6
 28000 -31.5 -24.7  260  45 23   8.3   4.6 | -32.6 -26.7  250  48 25   8.3   4.6
 27000 -28.9 -20.0  260  44 23   9.0   5.0 | -30.0 -22.0  245  46 24   9.2   5.1
 26000 -26.2 -15.2  255  43 22   9.1   5.0 | -27.2 -17.0  240  44 23   9.3   5.1
 25000 -23.5 -10.3  250  43 22   9.0   5.0 | -24.4 -11.9  240  43 22   9.3   5.1
 24000 -20.9  -5.6  250  41 21   7.9   4.3 | -21.8  -7.2  235  42 21   7.3   4.0
 23000 -18.6  -1.5  250  38 19   7.9   4.3 | -19.6  -3.3  240  38 20   7.4   4.1
 22000 -16.2   2.8  255  34 18   7.8   4.3 | -17.3   0.9  240  34 18   7.4   4.1
 21000 -14.3   6.3  250  30 16   4.7   2.6 | -15.2   4.6  245  30 15   6.3   3.5
 20000 -12.9   8.8  245  26 13   4.6   2.5 | -13.3   8.1  245  25 13   6.4   3.5
 19500 -12.3   9.9  245  24 12   4.7   2.6 | -12.4   9.7  245  23 12   6.4   3.5
 19000 -11.6  11.1  240  22 11   5.1   2.8 | -11.4  11.5  245  20 11   6.3   3.5
 18500 -10.3  13.5  235  21 11  10.2   5.6 | -10.4  13.3  245  19 10   6.7   3.7
 18000  -8.9  16.0  230  22 11   9.9   5.4 |  -9.4  15.1  240  19 10   6.7   3.7
 17500  -7.4  18.7  225  22 11   8.7   4.8 |  -8.4  16.9  240  20 10   6.2   3.4
 17000  -6.2  20.8  230  21 11   8.3   4.5 |  -7.1  19.2  235  19 10   5.8   3.2
 16500  -4.9  23.2  230  20 10   7.8   4.3 |  -6.3  20.7  235  19 10   7.0   3.8
 16000  -4.0  24.8  225  18  9   5.6   3.1 |  -5.1  22.8  230  17  9   7.8   4.3
 15500  -3.2  26.2  220  16  8   5.8   3.2 |  -3.9  25.0  230  16  8   7.7   4.2
 15000  -2.3  27.9  215  15  8   5.8   3.2 |  -2.9  26.8  225  14  7   6.7   3.7
 14500  -1.1  30.0  210  11  6   6.1   3.3 |  -1.9  28.6  220  11  6   6.5   3.6
 14000   0.0  32.0  205   9  5   8.8   4.8 |  -0.8  30.6  220  10  5   9.1   5.0
 13500   1.3  34.3  205   7  4   8.6   4.7 |   0.5  32.9  220   9  5   8.8   4.8
 13000   2.6  36.7  215   6  3   9.0   4.9 |   1.8  35.2  220   9  5   9.6   5.3
 12500   3.9  39.0  235   6  3   9.1   5.0 |   3.3  37.9  225   9  5   9.7   5.3
 12000   5.1  41.2  255   8  4   7.2   4.0 |   4.7  40.5  235  10  5   8.9   4.9
 11500   6.1  43.0  270  13  7   7.4   4.0 |   6.0  42.8  260  14  7   8.9   4.9
 11000   6.9  44.4  275  18  9   4.1   2.2 |   7.1  44.8  270  20 10   4.4   2.4
 10500   7.5  45.5  275  22 12   3.5   1.9 |   7.5  45.5  275  25 13   3.4   1.9
 10250   7.7  45.9  280  25 13   3.9   2.1 |   7.7  45.9  275  27 14   1.5   0.8
 10000   8.0  46.4  280  27 14   3.3   1.8 |   7.6  45.7  275  27 14   0.4   0.2
  9750   8.1  46.6  280  27 14   2.6   1.4 |   7.6  45.7  275  24 12   1.6   0.9
  9500   8.3  46.9  280  28 14   2.9   1.6 |   7.6  45.7  275  21 11   1.0   0.5
  9250   8.4  47.1  280  28 15   2.9   1.6 |   7.7  45.9  275  18  9   3.0   1.6
  9000   8.7  47.7  280  27 14   4.4   2.4 |   8.0  46.4  275  15  8   6.5   3.5
  8750   9.0  48.2  280  25 13   5.6   3.1 |   8.5  47.3  270  13  6   7.3   4.0
  8500   9.3  48.7  280  23 12   4.9   2.7 |   9.0  48.2  265  10  5   6.8   3.7
  8250   9.7  49.5  280  20 10   6.6   3.6 |   9.5  49.1  255   8  4   7.9   4.3
  8000  10.2  50.4  280  18  9   7.8   4.3 |  10.1  50.2  245   6  3   8.9   4.9
  7750  10.7  51.3  280  15  8   6.8   3.7 |  10.8  51.4  240   5  3   8.6   4.7
  7500  11.3  52.3  280  13  7   6.9   3.8 |  11.4  52.5  230   5  2   8.6   4.7
  7250  11.8  53.2  275  11  6   7.7   4.2 |  12.1  53.8  225   4  2   9.8   5.4
  7000  12.4  54.3  270   9  5   7.9   4.3 |  12.8  55.0  220   4  2  10.7   5.9
  6750  13.0  55.4  265   7  4   8.1   4.5 |  13.6  56.5  220   4  2   9.7   5.3
  6500  13.5  56.3  255   6  3   5.1   2.8 |  14.3  57.7  220   4  2   9.7   5.3
  6250  13.7  56.7  235   5  3   0.7   0.4 |  15.1  59.2  220   4  2  10.2   5.6
  6000  13.7  56.7  215   5  3   1.1   0.6 |  15.9  60.6  215   4  2  10.2   5.6
  5750  13.8  56.8  200   6  3  -1.7  -1.0 |  16.6  61.9  215   4  2  10.6   5.8
  5500  13.2  55.8  190   8  4 -15.1  -8.3 |  17.5  63.5  215   4  2  15.0   8.2

           10/26/2014 at 1500 MDT          |       10/26/2014 at 1800 MDT
                                           |
K index... +2.8  LI... +2.1                | K index... +15.2  LI... +0.6
CAPE... 0.0  CIN... -2.9                   | CAPE... 0.0  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 -64.1 -83.4  250  64 33   0.6   0.3 | -62.9 -81.2  250  54 28   0.1   0.1
 45000 -62.7 -80.9  250  93 48   3.4   1.9 | -62.3 -80.1  250  86 44   3.1   1.7
 40000 -57.4 -71.3  250  87 45   3.5   1.9 | -57.6 -71.7  255  84 43   3.2   1.7
 38000 -54.8 -66.6  250  84 43   4.5   2.5 | -55.1 -67.2  255  83 43   4.4   2.4
 36000 -52.1 -61.8  250  79 41   4.5   2.5 | -52.5 -62.5  255  81 42   4.4   2.4
 34000 -48.6 -55.5  250  75 39   7.6   4.2 | -49.2 -56.6  255  78 40   7.4   4.1
 32000 -43.5 -46.3  250  69 35   7.5   4.1 | -44.7 -48.5  250  72 37   7.4   4.1
 30000 -38.8 -37.8  250  64 33   8.2   4.5 | -39.4 -38.9  250  67 34   8.4   4.6
 29000 -36.3 -33.3  250  62 32   8.2   4.5 | -36.9 -34.4  250  65 34   8.4   4.6
 28000 -33.8 -28.8  255  60 31   8.3   4.5 | -34.3 -29.7  250  64 33   8.4   4.6
 27000 -31.3 -24.3  250  57 29   8.6   4.7 | -31.8 -25.2  250  61 31   8.6   4.7
 26000 -28.7 -19.7  250  52 27   8.6   4.7 | -29.2 -20.6  250  56 29   8.6   4.7
 25000 -26.2 -15.2  245  47 24   8.6   4.7 | -26.6 -15.9  245  52 27   8.6   4.7
 24000 -23.7 -10.7  240  43 22   7.5   4.1 | -24.0 -11.2  245  48 25   8.4   4.6
 23000 -21.4  -6.5  240  38 19   7.6   4.2 | -21.5  -6.7  245  46 24   8.4   4.6
 22000 -19.1  -2.4  240  32 17   7.6   4.2 | -19.0  -2.2  245  44 23   8.4   4.6
 21000 -16.7   1.9  245  29 15   9.0   5.0 | -16.7   1.9  250  42 22   6.2   3.4
 20000 -14.0   6.8  250  29 15   9.0   4.9 | -14.8   5.4  255  39 20   6.3   3.5
 19500 -12.6   9.3  255  30 15   9.0   4.9 | -13.9   7.0  260  38 19   6.3   3.5
 19000 -11.3  11.7  255  30 15   9.2   5.0 | -12.9   8.8  265  36 19   6.2   3.4
 18500 -10.1  13.8  260  30 16   6.9   3.8 | -11.9  10.6  265  36 18   7.9   4.3
 18000  -9.0  15.8  265  31 16   7.0   3.8 | -10.7  12.7  265  35 18   7.9   4.3
 17500  -8.0  17.6  265  31 16   7.1   3.9 |  -9.5  14.9  265  34 18   7.5   4.1
 17000  -6.9  19.6  270  32 16   7.1   3.9 |  -8.6  16.5  265  34 18   6.3   3.4
 16500  -5.8  21.6  270  32 17   7.3   4.0 |  -7.6  18.3  265  34 17   6.5   3.6
 16000  -4.4  24.1  275  33 17   6.4   3.5 |  -6.8  19.8  265  33 17   5.0   2.7
 15500  -3.4  25.9  275  34 17   6.3   3.5 |  -6.1  21.0  265  31 16   5.2   2.8
 15000  -2.6  27.3  275  34 18   5.4   3.0 |  -5.0  23.0  260  28 14   6.0   3.3
 14500  -1.8  28.8  275  34 18   5.7   3.1 |  -4.2  24.4  255  25 13   5.9   3.3
 14000  -1.1  30.0  270  34 18   4.6   2.5 |  -3.2  26.2  250  22 11   8.1   4.5
 13500  -0.5  31.1  270  33 17   4.9   2.7 |  -2.1  28.2  250  20 10   8.2   4.5
 13000   0.1  32.2  265  31 16   5.3   2.9 |  -0.9  30.4  245  17  9   8.6   4.7
 12500   0.9  33.6  265  28 14   5.5   3.0 |   0.4  32.7  240  15  7   8.7   4.8
 12000   1.6  34.9  265  24 12   6.6   3.6 |   1.6  34.9  230  12  6   9.3   5.1
 11500   2.6  36.7  265  19 10   7.0   3.9 |   3.1  37.6  230  11  6   9.5   5.2
 11000   3.6  38.5  260  15  8   7.3   4.0 |   4.5  40.1  230  10  5   8.5   4.6
 10500   4.7  40.5  255  12  6   6.7   3.7 |   5.6  42.1  225   9  5   7.2   4.0
 10250   5.2  41.4  255  11  5  10.1   5.6 |   6.2  43.2  220   9  4  10.3   5.7
 10000   6.1  43.0  250   9  5  11.2   6.2 |   7.1  44.8  225   8  4  11.1   6.1
  9750   6.8  44.2  250   8  4   8.6   4.7 |   7.8  46.0  225   7  4   8.5   4.7
  9500   7.5  45.5  250   7  3   9.3   5.1 |   8.4  47.1  220   7  4   9.3   5.1
  9250   8.2  46.8  245   6  3   8.9   4.9 |   9.1  48.4  220   6  3   8.8   4.8
  9000   8.8  47.8  245   5  2   8.9   4.9 |   9.7  49.5  220   6  3   8.3   4.5
  8750   9.5  49.1  245   4  2   9.3   5.1 |  10.3  50.5  225   5  3   8.2   4.5
  8500  10.1  50.2  245   4  2   8.7   4.8 |  10.9  51.6  230   4  2   7.9   4.4
  8250  10.8  51.4  250   3  2  10.7   5.9 |  11.6  52.9  235   4  2   9.0   4.9
  8000  11.7  53.1  250   3  2  11.3   6.2 |  12.2  54.0  250   3  1   8.6   4.7
  7750  12.4  54.3  250   3  2   9.2   5.0 |  12.8  55.0  275   3  1   6.9   3.8
  7500  13.1  55.6  255   3  2   8.8   4.8 |  13.3  55.9  300   3  1   6.4   3.5
  7250  13.8  56.8  255   3  2  10.0   5.5 |  13.8  56.8  320   3  2   8.2   4.5
  7000  14.6  58.3  255   3  2  10.8   5.9 |  14.5  58.1  325   4  2  10.0   5.5
  6750  15.3  59.5  260   3  2   9.1   5.0 |  15.2  59.4  330   5  2   8.9   4.9
  6500  16.0  60.8  260   3  2   9.0   5.0 |  15.8  60.4  330   5  3   8.9   4.9
  6250  16.7  62.1  260   3  1  10.6   5.8 |  16.5  61.7  335   6  3   9.7   5.3
  6000  17.6  63.7  260   3  1  11.4   6.3 |  17.2  63.0  335   6  3  10.0   5.5
  5750  18.4  65.1  260   3  1  10.0   5.5 |  17.9  64.2  335   6  3   9.5   5.2
  5500  19.1  66.4  265   3  1  12.3   6.8 |  18.6  65.5  335   6  3   6.2   3.4
________________________________________________________________________________

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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