Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 101331
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0731 MDT Wednesday, September 10, 2014

This forecast is for Wednesday, September 10, 2014:

If the trigger temperature of 62.4 F/16.9 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 363 ft/min (1.8 m/s)
   Maximum height of thermals.................. 12807 ft MSL (7522 ft AGL)

Forecast maximum temperature................... 71.0 F/22.1 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11003 ft MSL (5717 ft AGL)
Thermal soaring outlook for Thursday 09/11..... Fair

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 NVA
Potential height of wave....................... 14371 ft MSL (9086 ft AGL)
Wave soaring outlook for Thursday 09/11........ Excellent

Remarks... Weather disturbance moving out of colorado this morning with flow
           aloft becoming more westerly after 1500 MDT.

Sunrise/Sunset.................... 06:35:53 / 19:17:43 MDT
Total possible sunshine........... 12 hr 41 min 49 sec (761 min 49 sec)
Altitude of sun at 12:56:19 MDT... 54.98 degrees

Upper air data from rawinsonde observation taken on 09/10/2014 at 0600 MDT

Freezing level.................. 11961 ft MSL (6676 ft AGL)
Convective condensation level... 9736 ft MSL (4451 ft AGL)
Lifted condensation level....... 11501 ft MSL (6216 ft AGL)
Lifted index.................... -3.0
K index......................... +27.1

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  -65.3 -85.5   250   65   34   0.1   0.0   84.9 184.9    36.7      M    M
 45000  -57.1 -70.8   245   90   46   7.0   3.9   74.1 165.4    32.6      M    M
 40000  -46.8 -52.2   245   99   51   5.8   3.2   66.4 151.5    29.8      M    M
 38000  -43.2 -45.8   250  103   53   6.0   3.3   62.8 145.0    28.2      M    M
 36000  -39.6 -39.3   250  108   56   6.0   3.3   59.9 139.7    26.8      M    M
 34000  -36.9 -34.4   250   92   47   3.3   1.8   55.3 131.6    24.2      M    M
 32000  -34.0 -29.2   250   82   42  -0.8  -0.4   51.4 124.6    22.0      M    M
 30000  -31.2 -24.2   245   84   43  -2.2  -1.2   47.3 117.2    19.4      M    M
 29000  -30.9 -23.6   245   77   40  -2.6  -1.4   43.8 110.8    16.9      M    M
 28000  -31.6 -24.9   245   70   36  -4.3  -2.4   39.1 102.4    13.5      M    M
 27000  -29.7 -21.5   245   61   31   7.5   4.1   36.8  98.3    11.9      M    M
 26000  -27.5 -17.5   250   54   28   7.5   4.1   36.0  96.8    11.4      M    M
 25000  -25.2 -13.4   250   47   24   7.5   4.1   35.2  95.4    10.9      M    M
 24000  -23.3  -9.9   250   41   21   4.4   2.4   34.1  93.3    10.1      M    M
 23000  -21.8  -7.2   250   32   17   9.4   5.2   32.3  90.2     8.7      M    M
 22000  -18.7  -1.7   255   24   12   8.9   4.9   32.7  90.8     8.9      M    M
 21000  -17.0   1.4   260   15    8   5.8   3.2   31.2  88.2     7.8      M    M
 20000  -14.5   5.9   250   16    8   9.7   5.3   30.9  87.6     7.5      M    M
 19500  -13.3   8.1   260   18    9   7.5   4.1   30.7  87.2     7.3      M    M
 19000  -12.2  10.0   270   20   10   7.4   4.1   30.3  86.5     7.0      M    M
 18500  -11.2  11.8   255   19   10   7.2   3.9   29.8  85.7     6.6      M    M
 18000  -10.1  13.8   250   20   10   6.9   3.8   29.4  84.9     6.3      M    M
 17500   -9.2  15.4   250   20   10   5.7   3.1   28.8  83.8     5.7      M    M
 17000   -8.4  16.9   245   21   11   5.8   3.2   28.1  82.6     5.1      M    M
 16500   -7.6  18.3   250   19   10   5.8   3.2   27.4  81.4     4.5      M    M
 16000   -6.7  19.9   255   16    8   5.8   3.2   26.8  80.2     3.9      M    M
 15500   -5.9  21.4   265   17    9   5.8   3.2   26.1  78.9     3.3      M    M
 15000   -5.0  23.0   275   20   10   6.0   3.3   25.4  77.7     2.7      M    M
 14500   -4.1  24.6   285   22   11   6.7   3.7   24.9  76.8     2.2      M    M
 14000   -2.7  27.1   295   25   13   6.7   3.7   24.1  75.4     1.5      M    M
 13500   -1.7  28.9   305   21   11   6.3   3.5   23.6  74.6     0.9      M    M
 13000   -1.1  30.0   320   19   10   3.8   2.1   22.8  73.1     0.2      M    M
 12500   -0.5  31.1   320   18    9   3.9   2.1   21.9  71.4    -0.7    537  2.7
 12000    0.1  32.2   320   17    9   3.9   2.2   20.9  69.7    -1.6    505  2.6
 11500    0.6  33.1   315   12    6   4.3   2.3   20.0  68.0    -2.5    473  2.4
 11000    1.5  34.7   305    8    4   7.8   4.3   19.5  67.0    -3.1    431  2.2
 10500    2.6  36.7   315    7    3   7.7   4.2   19.1  66.4    -3.4    384  1.9
 10250    3.2  37.8   325    6    3   7.2   4.0   19.0  66.1    -3.6    360  1.8
 10000    3.7  38.7   325    8    4   6.8   3.7   18.7  65.7    -3.9    338  1.7
  9750    4.2  39.6   330    9    5   6.8   3.7   18.5  65.3    -4.1    316  1.6
  9500    4.6  40.3   330   11    6   7.1   3.9   18.3  64.9    -4.4    294  1.5
  9250    5.1  41.2   330   13    6   5.8   3.2   18.0  64.5    -4.6    272  1.4
  9000    5.4  41.7   330   14    7   4.1   2.3   17.7  63.8    -5.0    255  1.3
  8750    5.7  42.3   335   12    6   4.2   2.3   17.2  63.0    -5.5    239  1.2
  8500    6.0  42.8   340   11    5   4.2   2.3   16.8  62.2    -5.9    223  1.1
  8250    6.3  43.3   345    9    5   4.2   2.3   16.4  61.5    -6.4    206  1.0
  8000    6.6  43.9   355    8    4   4.2   2.3   16.0  60.7    -6.8    190  1.0
  7750    6.9  44.4   010    9    5   4.2   2.3   15.5  59.9    -7.3    174  0.9
  7500    7.2  45.0   020   10    5   4.2   2.3   15.1  59.2    -7.7    158  0.8
  7250    7.5  45.5   030   11    6   4.2   2.3   14.7  58.4    -8.2    141  0.7
  7000    7.8  46.0   035   13    7   4.3   2.4   14.3  57.7    -8.6    125  0.6
  6750    8.1  46.6   045   13    7   3.8   2.1   13.8  56.9    -9.1    109  0.6
  6500    8.4  47.1   055   14    7   6.2   3.4   13.4  56.2    -9.5     92  0.5
  6250    9.0  48.2   060   15    8   8.5   4.6   13.3  55.9    -9.7     67  0.3
  6000    9.6  49.3   070   16    8   7.9   4.3   13.2  55.7    -9.8     42  0.2
  5750   10.2  50.4   060   12    6   7.8   4.3   13.0  55.5   -10.0     17  0.1
  5500   10.8  51.4   040    9    5   8.6   4.7   12.9  55.2   -10.2      M    M

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

           09/10/2014 at 0900 MDT          |       09/10/2014 at 1200 MDT
                                           |
K index... +24.1  LI... -1.6               | K index... +12.6  LI... -1.4
CAPE... +236.4  CIN... M                   | CAPE... +170.6  CIN... -40.5
                                           |
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 -63.5 -82.3  255  62 32   2.7   1.5 | -63.6 -82.5  255  62 32   2.3   1.3
 45000 -57.8 -72.0  250  88 46   6.6   3.6 | -58.5 -73.3  255  83 43   6.1   3.3
 40000 -47.9 -54.2  250  86 44   6.2   3.4 | -49.4 -56.9  255  79 41   6.0   3.3
 38000 -44.2 -47.6  250  83 43   6.2   3.4 | -45.9 -50.6  260  72 37   5.9   3.3
 36000 -40.5 -40.9  250  81 41   6.2   3.4 | -42.3 -44.1  260  66 34   6.0   3.3
 34000 -37.3 -35.1  250  76 39   4.6   2.5 | -39.3 -38.7  265  57 29   4.4   2.4
 32000 -34.2 -29.6  255  68 35   4.6   2.5 | -36.7 -34.1  275  48 25   4.4   2.4
 30000 -32.5 -26.5  260  57 29   1.8   1.0 | -33.4 -28.1  290  41 21   5.3   2.9
 29000 -31.9 -25.4  265  49 25   1.9   1.0 | -31.8 -25.2  295  39 20   5.3   2.9
 28000 -31.4 -24.5  270  42 22   1.8   1.0 | -30.3 -22.5  300  36 19   5.2   2.9
 27000 -29.9 -21.8  275  38 19   6.9   3.8 | -28.7 -19.7  300  35 18   5.5   3.0
 26000 -27.9 -18.2  280  36 18   7.0   3.8 | -27.0 -16.6  295  33 17   5.5   3.0
 25000 -25.8 -14.4  280  33 17   7.0   3.9 | -25.4 -13.7  290  32 16   5.6   3.1
 24000 -23.7 -10.7  285  32 16   7.3   4.0 | -23.4 -10.1  290  30 16   7.6   4.2
 23000 -21.5  -6.7  285  30 16   7.4   4.0 | -21.2  -6.2  290  30 15   7.7   4.2
 22000 -19.3  -2.7  285  29 15   7.4   4.1 | -18.9  -2.0  290  29 15   7.7   4.2
 21000 -17.2   1.0  285  28 14   6.7   3.7 | -16.8   1.8  290  28 15   6.8   3.7
 20000 -15.3   4.5  280  27 14   6.7   3.7 | -14.8   5.4  295  28 14   6.8   3.7
 19500 -14.3   6.3  280  26 14   6.7   3.7 | -13.8   7.2  295  28 14   6.7   3.7
 19000 -13.3   8.1  280  26 13   6.8   3.7 | -12.8   9.0  295  28 14   6.5   3.6
 18500 -12.3   9.9  280  25 13   7.3   4.0 | -11.9  10.6  295  27 14   5.8   3.2
 18000 -11.2  11.8  285  25 13   7.3   4.0 | -11.0  12.2  295  27 14   5.8   3.2
 17500 -10.2  13.6  290  24 12   6.7   3.7 | -10.2  13.6  295  27 14   6.3   3.5
 17000  -9.2  15.4  295  24 12   6.5   3.6 |  -9.2  15.4  295  26 13   6.4   3.5
 16500  -8.3  17.1  305  23 12   6.5   3.6 |  -8.3  17.1  295  25 13   6.5   3.6
 16000  -6.8  19.8  315  23 12   6.4   3.5 |  -7.3  18.9  300  24 12   6.8   3.8
 15500  -5.9  21.4  320  23 12   6.6   3.6 |  -6.2  20.8  300  23 12   6.8   3.8
 15000  -4.9  23.2  325  24 12   6.8   3.7 |  -4.6  23.7  305  23 12   7.3   4.0
 14500  -3.9  25.0  330  24 12   6.6   3.6 |  -3.6  25.5  310  22 12   7.5   4.1
 14000  -3.0  26.6  330  23 12   5.9   3.2 |  -2.4  27.7  310  22 11   8.0   4.4
 13500  -2.2  28.0  330  23 12   5.9   3.3 |  -1.2  29.8  315  22 11   8.0   4.4
 13000  -1.3  29.7  330  21 11   5.7   3.1 |  -0.1  31.8  315  21 11   7.9   4.3
 12500  -0.5  31.1  325  19 10   5.7   3.1 |   1.1  34.0  315  21 11   7.9   4.4
 12000   0.3  32.5  325  18  9   5.6   3.1 |   2.2  36.0  315  20 10   8.0   4.4
 11500   1.1  34.0  320  16  8   5.6   3.1 |   3.3  37.9  315  20 10   8.1   4.4
 11000   1.9  35.4  315  15  7   6.3   3.4 |   4.4  39.9  315  19 10   6.7   3.7
 10500   2.8  37.0  310  13  7   6.6   3.6 |   5.4  41.7  315  17  9   6.4   3.5
 10250   3.2  37.8  310  13  7   3.5   1.9 |   5.7  42.3  310  17  9   4.0   2.2
 10000   3.4  38.1  310  12  6   4.5   2.4 |   6.0  42.8  310  16  8   5.6   3.1
  9750   3.9  39.0  305  12  6   8.0   4.4 |   6.6  43.9  305  15  8   8.2   4.5
  9500   4.4  39.9  300  11  6   7.0   3.9 |   7.1  44.8  305  14  7   7.1   3.9
  9250   4.9  40.8  295  10  5   5.0   2.7 |   7.5  45.5  300  13  7   4.8   2.6
  9000   5.2  41.4  295  10  5   4.5   2.4 |   7.7  45.9  300  12  6   3.5   1.9
  8750   5.6  42.1  295   9  4   6.0   3.3 |   8.0  46.4  290  10  5   3.8   2.1
  8500   6.0  42.8  290   8  4   5.8   3.2 |   8.2  46.8  280   9  4   4.5   2.4
  8250   6.3  43.3  290   6  3   5.7   3.1 |   8.5  47.3  270   7  3   5.7   3.1
  8000   6.7  44.1  290   5  3   5.9   3.2 |   8.9  48.0  240   5  3   6.8   3.7
  7750   7.2  45.0  290   4  2   6.8   3.7 |   9.3  48.7  215   4  2   7.8   4.3
  7500   7.7  45.9  290   3  1   6.4   3.5 |   9.9  49.8  190   5  2   9.3   5.1
  7250   8.1  46.6  290   1  1   5.7   3.1 |  10.6  51.1  190   5  2  10.4   5.7
  7000   8.5  47.3  000   0  0   5.7   3.1 |  11.4  52.5  185   5  2  10.0   5.5
  6750   8.9  48.0  110   2  1   6.7   3.7 |  12.1  53.8  185   5  2  10.1   5.5
  6500   9.4  48.9  110   3  1   9.1   5.0 |  12.9  55.2  185   5  2  10.6   5.8
  6250  10.1  50.2  100   3  2  10.5   5.8 |  13.7  56.7  180   5  2  11.9   6.5
  6000  10.8  51.4  095   3  2   8.5   4.7 |  14.5  58.1  180   4  2   8.5   4.7
  5750  11.3  52.3  090   3  2  10.9   6.0 |  15.2  59.4  180   4  2  13.2   7.2
  5500  12.5  54.5  090   3  2  20.0  11.0 |  16.8  62.2  175   4  2  30.5  16.7

           09/10/2014 at 1500 MDT          |       09/10/2014 at 1800 MDT
                                           |
K index... +5.9  LI... -1.6                | K index... +23.5  LI... -1.0
CAPE... +101.1  CIN... -39.4               | CAPE... +41.1  CIN... -64.5
                                           |
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 -64.2 -83.6  260  59 30   2.3   1.3 | -65.1 -85.2  265  54 28   2.2   1.2
 45000 -59.4 -74.9  260  74 38   5.3   2.9 | -60.4 -76.7  265  67 34   5.5   3.0
 40000 -51.4 -60.5  265  66 34   5.9   3.3 | -52.1 -61.8  270  58 30   6.1   3.3
 38000 -47.8 -54.0  270  58 30   5.9   3.3 | -48.5 -55.3  280  57 30   6.0   3.3
 36000 -44.3 -47.7  280  51 26   5.9   3.3 | -44.9 -48.8  285  58 30   6.0   3.3
 34000 -41.0 -41.8  290  48 25   5.2   2.9 | -41.2 -42.2  290  58 30   6.2   3.4
 32000 -37.9 -36.2  295  47 24   5.2   2.9 | -37.5 -35.5  295  58 30   6.2   3.4
 30000 -33.3 -27.9  295  45 23   7.6   4.2 | -32.8 -27.0  295  55 28   7.4   4.1
 29000 -31.0 -23.8  300  43 22   7.6   4.2 | -30.5 -22.9  295  52 27   7.4   4.1
 28000 -28.8 -19.8  300  42 22   7.7   4.2 | -28.3 -18.9  295  50 26   7.4   4.1
 27000 -26.6 -15.9  305  40 21   6.9   3.8 | -26.3 -15.3  295  47 24   6.3   3.5
 26000 -24.6 -12.3  305  37 19   6.9   3.8 | -24.4 -11.9  295  45 23   6.4   3.5
 25000 -22.5  -8.5  310  35 18   6.9   3.8 | -22.5  -8.5  295  42 21   6.4   3.5
 24000 -20.6  -5.1  315  32 17   6.0   3.3 | -20.5  -4.9  295  40 20   7.2   3.9
 23000 -18.8  -1.8  310  30 15   6.0   3.3 | -18.3  -0.9  295  38 20   7.2   4.0
 22000 -17.0   1.4  310  28 14   6.0   3.3 | -16.2   2.8  290  37 19   7.3   4.0
 21000 -15.2   4.6  305  26 14   5.8   3.2 | -14.3   6.3  290  35 18   5.8   3.2
 20000 -13.5   7.7  305  26 13   5.8   3.2 | -12.5   9.5  290  33 17   5.8   3.2
 19500 -12.6   9.3  300  25 13   5.8   3.2 | -11.6  11.1  290  32 16   5.8   3.2
 19000 -11.7  10.9  300  25 13   6.3   3.4 | -10.8  12.6  290  31 16   5.9   3.2
 18500 -10.7  12.7  300  25 13   7.1   3.9 |  -9.9  14.2  285  30 15   6.0   3.3
 18000  -9.7  14.5  300  25 13   7.1   3.9 |  -9.0  15.8  285  29 15   6.0   3.3
 17500  -8.6  16.5  300  25 13   7.0   3.9 |  -8.1  17.4  285  29 15   7.1   3.9
 17000  -7.6  18.3  300  25 13   7.0   3.9 |  -7.1  19.2  285  29 15   7.3   4.0
 16500  -6.5  20.3  300  26 13   7.0   3.8 |  -6.1  21.0  280  29 15   7.6   4.2
 16000  -5.5  22.1  295  26 14   7.0   3.8 |  -5.0  23.0  280  29 15   7.9   4.4
 15500  -4.5  23.9  295  27 14   7.0   3.8 |  -3.9  25.0  275  29 15   8.1   4.5
 15000  -2.9  26.8  295  29 15   7.2   3.9 |  -2.1  28.2  275  27 14   8.5   4.7
 14500  -1.9  28.6  290  30 15   7.5   4.1 |  -0.9  30.4  270  25 13   8.2   4.5
 14000  -0.8  30.6  290  30 16   7.9   4.3 |   0.2  32.4  270  23 12   7.8   4.3
 13500   0.4  32.7  290  31 16   8.0   4.4 |   1.4  34.5  270  21 11   7.8   4.3
 13000   1.5  34.7  290  30 15   7.9   4.3 |   2.5  36.5  270  19 10   7.7   4.2
 12500   2.6  36.7  290  29 15   8.0   4.4 |   3.6  38.5  265  17  9   7.7   4.2
 12000   3.8  38.8  290  27 14   8.5   4.6 |   4.8  40.6  260  15  8   8.2   4.5
 11500   5.0  41.0  290  25 13   8.5   4.7 |   6.0  42.8  255  14  7   8.2   4.5
 11000   6.1  43.0  290  22 12   8.0   4.4 |   7.1  44.8  250  12  6   6.8   3.7
 10500   7.3  45.1  290  20 11   6.8   3.7 |   8.1  46.6  235  12  6   4.4   2.4
 10250   7.7  45.9  290  20 10   5.2   2.8 |   8.4  47.1  230  11  6   4.8   2.6
 10000   8.2  46.8  290  18  9   7.6   4.2 |   8.9  48.0  225  11  5   9.3   5.1
  9750   8.8  47.8  290  16  8   8.9   4.9 |   9.6  49.3  220  10  5   9.0   4.9
  9500   9.4  48.9  290  14  7   8.3   4.6 |  10.3  50.5  210  10  5   8.9   4.9
  9250   9.9  49.8  290  12  6   6.3   3.4 |  10.9  51.6  205   9  5   7.3   4.0
  9000  10.3  50.5  285   9  5   5.3   2.9 |  11.4  52.5  195   9  4   7.1   3.9
  8750  10.6  51.1  275   6  3   5.6   3.1 |  11.9  53.4  185   8  4   8.0   4.4
  8500  11.0  51.8  255   3  2   6.5   3.6 |  12.5  54.5  175   8  4   8.1   4.5
  8250  11.5  52.7  220   2  1   8.8   4.8 |  13.1  55.6  170   7  4   9.4   5.1
  8000  12.2  54.0  185   2  1   9.7   5.3 |  13.8  56.8  170   7  4   9.7   5.3
  7750  12.9  55.2  175   2  1   9.8   5.4 |  14.5  58.1  165   7  4   9.3   5.1
  7500  13.6  56.5  170   2  1  10.1   5.5 |  15.2  59.4  165   7  4   9.7   5.3
  7250  14.3  57.7  170   2  1  10.2   5.6 |  15.9  60.6  165   7  3  10.2   5.6
  7000  15.1  59.2  165   2  1  10.2   5.6 |  16.7  62.1  165   6  3  10.0   5.5
  6750  15.8  60.4  165   2  1  10.2   5.6 |  17.4  63.3  165   6  3   9.2   5.0
  6500  16.6  61.9  165   2  1  10.4   5.7 |  18.1  64.6  165   6  3   9.7   5.3
  6250  17.4  63.3  165   2  1  11.0   6.0 |  18.8  65.8  165   6  3  10.6   5.8
  6000  18.2  64.8  165   2  1   9.6   5.2 |  19.6  67.3  165   6  3  10.0   5.5
  5750  18.9  66.0  165   2  1  13.3   7.3 |  20.3  68.5  165   5  3  10.2   5.6
  5500  20.3  68.5  160   2  1  24.4  13.4 |  21.1  70.0  160   5  3  11.9   6.5
________________________________________________________________________________

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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