Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 280026
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1826 MDT Monday, October 27, 2014

This forecast is for Tuesday, October 28, 2014:

If the trigger temperature of 49.9 F/10.0 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 582 ft/min (3.0 m/s)
   Maximum height of thermals.................. 13148 ft MSL (7861 ft AGL)

Forecast maximum temperature................... 60.0 F/16.0 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11428 ft MSL (6141 ft AGL)
Thermal soaring outlook for Wednesday 10/29.... Good

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 14902 ft MSL (9615 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 45471 ft MSL (40184 ft AGL)
Wave soaring outlook for Wednesday 10/29....... Fair

Remarks... None

Sunrise/Sunset.................... 07:23:50 / 18:03:36 MDT
Total possible sunshine........... 10 hr 39 min 46 sec (639 min 46 sec)
Altitude of sun at 12:43:21 MDT... 36.98 degrees

Upper air data from numerical model forecast valid on 10/28/2014 at 0600 MDT

Freezing level.................. 8448 ft MSL (3161 ft AGL)
Convective condensation level... 16562 ft MSL (11275 ft AGL)
Lifted condensation level....... 14590 ft MSL (9303 ft AGL)
Lifted index.................... +5.9
K index......................... -12.5

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   320   57   30   2.6   1.4      M     M       M      M    M
 45000  -57.4 -71.3   325   67   35   4.0   2.2      M     M       M      M    M
 40000  -51.5 -60.7   320   67   34   4.0   2.2      M     M       M      M    M
 38000  -49.6 -57.3   315   65   33   2.5   1.4      M     M       M      M    M
 36000  -48.1 -54.6   305   63   32   2.5   1.4      M     M       M      M    M
 34000  -46.1 -51.0   300   61   32   4.0   2.2      M     M       M      M    M
 32000  -43.7 -46.7   295   59   30   4.0   2.2      M     M       M      M    M
 30000  -41.1 -42.0   290   57   29   5.0   2.7   35.6  96.2    15.1      M    M
 29000  -39.6 -39.3   290   56   29   5.0   2.7   33.7  92.6    13.8      M    M
 28000  -38.1 -36.6   285   56   29   5.0   2.7   31.8  89.3    12.5      M    M
 27000  -36.5 -33.7   285   56   29   7.8   4.3   30.3  86.5    11.5      M    M
 26000  -33.9 -29.0   285   55   28   8.8   4.8   29.8  85.6    11.2      M    M
 25000  -31.3 -24.3   285   53   28   8.8   4.8   29.4  85.0    11.1      M    M
 24000  -28.6 -19.5   290   52   27   8.4   4.6   29.2  84.5    11.0      M    M
 23000  -26.3 -15.3   285   50   26   8.0   4.4   28.4  83.1    10.5      M    M
 22000  -23.9 -11.0   285   48   25   8.0   4.4   27.8  82.0    10.0      M    M
 21000  -21.6  -6.9   285   46   24   5.9   3.2   27.1  80.8     9.5      M    M
 20000  -20.0  -4.0   290   43   22   5.4   3.0   25.5  77.8     8.2      M    M
 19500  -19.2  -2.6   290   41   21   5.4   3.0   24.7  76.5     7.6      M    M
 19000  -18.4  -1.1   290   39   20   5.4   3.0   24.0  75.1     7.0      M    M
 18500  -17.6   0.3   290   38   19   6.0   3.3   23.3  73.9     6.5      M    M
 18000  -16.6   2.1   290   36   19   6.4   3.5   22.7  72.8     6.0      M    M
 17500  -15.6   3.9   295   35   18   6.5   3.6   22.1  71.8     5.6      M    M
 17000  -14.5   5.9   295   34   17   8.2   4.5   21.7  71.1     5.3      M    M
 16500  -12.6   9.3   295   32   16   7.6   4.1   21.3  70.3     5.0      M    M
 16000  -11.7  10.9   295   30   16   5.4   2.9   20.7  69.2     4.5      M    M
 15500  -10.9  12.4   295   29   15   5.7   3.1   20.0  67.9     3.9      M    M
 15000  -10.2  13.6   295   27   14   3.2   1.8   19.1  66.4     3.1      M    M
 14500   -9.7  14.5   295   25   13   3.4   1.9   18.0  64.5     2.2      M    M
 14000   -9.1  15.6   295   23   12   4.2   2.3   17.1  62.7     1.3      M    M
 13500   -8.5  16.7   295   22   11   4.3   2.4   16.2  61.1     0.5      M    M
 13000   -7.9  17.8   295   20   10   4.2   2.3   15.3  59.5    -0.4    567  2.9
 12500   -7.3  18.9   295   19   10   4.1   2.3   14.3  57.8    -1.3    534  2.7
 12000   -6.7  19.9   295   17    9   4.5   2.4   13.5  56.2    -2.1    502  2.5
 11500   -6.0  21.2   290   14    7   4.5   2.5   12.6  54.7    -3.0    467  2.4
 11000   -5.3  22.5   290   12    6   6.1   3.4   11.9  53.4    -3.7    431  2.2
 10500   -4.4  24.1   285   10    5   7.3   4.0   11.3  52.4    -4.3    388  2.0
 10250   -3.9  25.0   285    9    5   3.4   1.9   11.1  52.0    -4.5    366  1.9
 10000   -3.7  25.3   285    9    5   4.4   2.4   10.5  50.8    -5.1    355  1.8
  9750   -3.1  26.4   280    8    4   9.9   5.4   10.4  50.7    -5.3    329  1.7
  9500   -2.4  27.7   280    8    4   9.9   5.4   10.3  50.6    -5.3    301  1.5
  9250   -1.7  28.9   275    7    3   7.8   4.3   10.3  50.6    -5.4    272  1.4
  9000   -1.3  29.7   270    6    3   6.1   3.4   10.1  50.1    -5.7    251  1.3
  8750   -0.7  30.7   270    6    3   8.2   4.5    9.9  49.8    -5.9    228  1.2
  8500   -0.1  31.8   265    6    3   8.6   4.7    9.8  49.6    -6.0    201  1.0
  8250    0.5  32.9   265    6    3   8.2   4.5    9.7  49.4    -6.1    175  0.9
  8000    1.1  34.0   265    5    3   8.0   4.4    9.5  49.2    -6.3    150  0.8
  7750    1.7  35.1   265    5    3   8.4   4.6    9.4  49.0    -6.4    124  0.6
  7500    2.3  36.1   265    5    3   8.2   4.5    9.3  48.8    -6.5     98  0.5
  7250    2.9  37.2   265    5    2   7.6   4.2    9.2  48.5    -6.7     73  0.4
  7000    3.5  38.3   265    4    2   7.9   4.3    9.0  48.2    -6.9     49  0.2
  6750    4.1  39.4   270    4    2   6.9   3.8    8.9  47.9    -7.0     24  0.1
  6500    4.5  40.1   265    3    2   5.3   2.9    8.6  47.4    -7.4      4  0.0
  6250    4.8  40.6   250    3    2   2.2   1.2    8.1  46.6    -7.8      M    M
  6000    5.1  41.2   235    3    2  10.9   6.0    7.7  45.9    -8.3      M    M
  5750    5.9  42.6   220    2    1   0.1   0.0    7.8  46.1    -8.2      M    M
  5500    4.2  39.6   205    3    2 -42.2 -23.2    5.5  41.9   -10.7      M    M

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

           10/28/2014 at 0900 MDT          |       10/28/2014 at 1200 MDT
                                           |
K index... -8.3  LI... +8.4                | K index... -9.4  LI... +9.7
CAPE... 0.0  CIN... -0.3                   | 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 -62.9 -81.2  325  61 31   3.5   1.9 | -63.0 -81.4  325  57 29   3.5   1.9
 45000 -57.5 -71.5  325  79 41   5.0   2.7 | -57.3 -71.1  325  75 39   5.4   3.0
 40000 -49.7 -57.5  325  77 39   4.9   2.7 | -49.2 -56.6  320  79 41   5.4   3.0
 38000 -47.6 -53.7  320  73 38   3.2   1.7 | -46.5 -51.7  320  77 39   4.2   2.3
 36000 -45.7 -50.3  315  70 36   3.2   1.7 | -43.9 -47.0  320  73 38   4.2   2.3
 34000 -43.9 -47.0  310  66 34   2.7   1.5 | -41.7 -43.1  315  68 35   1.9   1.1
 32000 -42.2 -44.0  305  62 32   2.7   1.5 | -40.5 -40.9  310  60 31   1.9   1.1
 30000 -40.3 -40.5  305  58 30   4.8   2.6 | -39.0 -38.2  310  55 28   3.3   1.8
 29000 -38.5 -37.3  300  57 29   4.8   2.6 | -38.1 -36.6  310  53 27   3.3   1.8
 28000 -37.1 -34.8  300  56 29   4.8   2.6 | -37.1 -34.8  310  52 27   3.3   1.8
 27000 -35.4 -31.7  300  55 28   7.7   4.2 | -35.8 -32.4  310  50 26   7.9   4.4
 26000 -33.1 -27.6  300  54 28   7.7   4.2 | -33.4 -28.1  310  50 26   7.9   4.3
 25000 -30.8 -23.4  300  54 28   7.7   4.2 | -31.0 -23.8  310  49 25   7.9   4.3
 24000 -28.5 -19.3  300  53 27   7.8   4.3 | -28.6 -19.5  315  48 25   8.4   4.6
 23000 -26.2 -15.2  300  52 27   7.9   4.3 | -26.0 -14.8  315  48 25   8.7   4.8
 22000 -23.8 -10.8  305  50 26   7.9   4.3 | -23.4 -10.1  320  48 25   8.7   4.8
 21000 -21.6  -6.9  305  48 25   5.6   3.0 | -20.9  -5.6  320  47 24   7.7   4.2
 20000 -19.9  -3.8  305  46 24   5.7   3.1 | -18.6  -1.5  320  45 23   7.8   4.3
 19500 -19.1  -2.4  305  45 23   5.7   3.1 | -17.4   0.7  320  44 23   7.8   4.3
 19000 -18.3  -0.9  305  43 22   5.8   3.2 | -16.3   2.7  320  43 22   7.9   4.3
 18500 -17.5   0.5  305  42 22   4.9   2.7 | -15.2   4.6  320  42 22   5.7   3.1
 18000 -16.8   1.8  300  40 20   4.7   2.6 | -14.5   5.9  320  40 21   5.2   2.8
 17500 -16.1   3.0  300  38 19   5.1   2.8 | -13.7   7.3  320  39 20   4.9   2.7
 17000 -15.1   4.8  300  35 18   7.2   4.0 | -13.1   8.4  315  37 19   3.9   2.1
 16500 -14.1   6.6  300  33 17   7.1   3.9 | -12.2  10.0  310  35 18   4.4   2.4
 16000 -13.0   8.6  305  31 16   7.6   4.1 | -11.5  11.3  310  34 17   5.1   2.8
 15500 -11.8  10.8  305  29 15   7.6   4.2 | -10.7  12.7  310  33 17   5.2   2.8
 15000 -10.7  12.7  305  27 14   5.8   3.2 |  -9.7  14.5  305  31 16   6.8   3.7
 14500  -9.6  14.7  305  24 12   5.1   2.8 |  -8.7  16.3  305  29 15   6.8   3.8
 14000  -8.9  16.0  305  22 11   3.9   2.1 |  -7.8  18.0  305  27 14   5.3   2.9
 13500  -8.3  17.1  305  20 10   3.9   2.1 |  -7.0  19.4  305  25 13   5.4   3.0
 13000  -7.7  18.1  305  17  9   4.6   2.5 |  -6.2  20.8  305  23 12   4.5   2.5
 12500  -7.0  19.4  305  15  8   4.7   2.6 |  -5.6  21.9  300  20 10   4.4   2.4
 12000  -6.3  20.7  305  13  7   5.0   2.7 |  -4.9  23.2  300  18  9   4.7   2.6
 11500  -5.6  21.9  300  12  6   5.1   2.8 |  -4.2  24.4  295  15  8   4.6   2.5
 11000  -4.9  23.2  300  10  5   5.3   2.9 |  -3.5  25.7  295  12  6   6.0   3.3
 10500  -4.1  24.6  295   9  4   5.9   3.3 |  -2.6  27.3  290  11  5   6.8   3.7
 10250  -3.7  25.3  290   8  4   3.1   1.7 |  -2.1  28.2  290  10  5   3.4   1.9
 10000  -3.5  25.7  290   8  4   4.3   2.4 |  -2.0  28.4  290  10  5   3.9   2.2
  9750  -3.0  26.6  285   7  4   8.4   4.6 |  -1.5  29.3  285   9  5   7.8   4.3
  9500  -2.4  27.7  280   6  3   7.9   4.4 |  -1.0  30.2  280   8  4   7.3   4.0
  9250  -1.9  28.6  270   5  3   6.7   3.7 |  -0.5  31.1  275   8  4   5.3   2.9
  9000  -1.5  29.3  270   5  3   6.3   3.5 |  -0.2  31.6  270   7  3   3.9   2.1
  8750  -0.9  30.4  265   5  2   8.5   4.7 |   0.2  32.4  265   6  3   5.5   3.0
  8500  -0.3  31.5  260   5  2   8.8   4.8 |   0.6  33.1  250   5  3   6.0   3.3
  8250   0.4  32.7  250   4  2   7.7   4.2 |   1.0  33.8  230   4  2   6.8   3.7
  8000   0.9  33.6  245   4  2   7.5   4.1 |   1.5  34.7  205   4  2   7.4   4.0
  7750   1.5  34.7  240   4  2   8.0   4.4 |   2.1  35.8  180   5  2   7.7   4.2
  7500   2.1  35.8  240   4  2   8.3   4.6 |   2.6  36.7  165   5  3   9.4   5.1
  7250   2.7  36.9  235   4  2   8.2   4.5 |   3.4  38.1  165   5  3  10.4   5.7
  7000   3.3  37.9  230   4  2   8.4   4.6 |   4.2  39.6  165   5  3  10.2   5.6
  6750   3.9  39.0  225   4  2   7.7   4.2 |   4.9  40.8  160   5  3  10.3   5.6
  6500   4.5  40.1  220   3  2   6.7   3.7 |   5.7  42.3  160   5  3  10.2   5.6
  6250   5.0  41.0  205   3  2   8.1   4.4 |   6.5  43.7  160   5  3  10.2   5.6
  6000   5.5  41.9  190   3  2   3.6   2.0 |   7.2  45.0  160   5  2  10.1   5.5
  5750   5.3  41.5  185   4  2  -3.8  -2.1 |   8.1  46.6  160   5  2  14.0   7.7
  5500   4.9  40.8  185   3  2  -2.4  -1.3 |   9.4  48.9  160   5  2  20.6  11.3

           10/28/2014 at 1500 MDT          |       10/28/2014 at 1800 MDT
                                           |
K index... -4.7  LI... +8.1                | K index... -0.9  LI... +6.7
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -63.4 -82.1  320  54 28   3.2   1.8 | -63.7 -82.7  310  47 24   3.8   2.1
 45000 -58.1 -72.6  315  68 35   5.5   3.0 | -57.7 -71.9  310  58 30   5.2   2.9
 40000 -49.4 -56.9  315  74 38   5.5   3.0 | -49.4 -56.9  310  66 34   5.3   2.9
 38000 -45.9 -50.6  315  74 38   5.9   3.3 | -45.8 -50.4  310  66 34   6.1   3.3
 36000 -42.4 -44.3  315  74 38   5.9   3.3 | -42.2 -44.0  310  67 34   6.1   3.3
 34000 -39.8 -39.6  315  71 36   1.9   1.0 | -39.3 -38.7  310  65 34   2.9   1.6
 32000 -38.7 -37.7  310  64 33   1.9   1.0 | -37.6 -35.7  310  62 32   2.9   1.6
 30000 -37.4 -35.3  310  56 29   2.5   1.4 | -36.1 -33.0  310  58 30   1.5   0.8
 29000 -36.7 -34.1  310  52 27   2.5   1.4 | -35.6 -32.1  310  54 28   1.4   0.8
 28000 -35.9 -32.6  310  48 25   2.5   1.4 | -35.1 -31.2  310  51 26   1.5   0.8
 27000 -34.7 -30.5  310  44 23   6.0   3.3 | -34.2 -29.6  310  48 25   6.4   3.5
 26000 -33.0 -27.4  305  44 22   5.8   3.2 | -32.4 -26.3  310  47 24   6.0   3.3
 25000 -31.2 -24.2  305  43 22   5.8   3.2 | -30.6 -23.1  310  45 23   6.0   3.3
 24000 -29.3 -20.7  305  43 22   9.1   5.0 | -28.7 -19.7  310  43 22   7.9   4.3
 23000 -26.6 -15.9  305  42 22   9.3   5.1 | -26.3 -15.3  310  41 21   7.9   4.4
 22000 -23.8 -10.8  305  41 21   9.3   5.1 | -24.0 -11.2  305  39 20   8.0   4.4
 21000 -21.1  -6.0  305  40 21   9.0   4.9 | -21.6  -6.9  305  37 19   8.3   4.6
 20000 -18.4  -1.1  305  40 20   9.0   5.0 | -19.1  -2.4  305  34 18   8.3   4.6
 19500 -17.0   1.4  310  39 20   9.1   5.0 | -17.9  -0.2  300  33 17   8.4   4.6
 19000 -15.7   3.7  310  39 20   9.4   5.2 | -16.6   2.1  300  32 16   8.4   4.6
 18500 -14.6   5.7  310  38 19   5.8   3.2 | -15.4   4.3  300  31 16   7.9   4.3
 18000 -13.7   7.3  310  36 18   5.8   3.2 | -14.2   6.4  300  29 15   8.0   4.4
 17500 -12.8   9.0  315  34 18   5.3   2.9 | -13.0   8.6  295  28 15   7.9   4.3
 17000 -12.1  10.2  310  32 16   4.6   2.5 | -11.9  10.6  300  28 14   7.8   4.3
 16500 -11.4  11.5  310  29 15   4.5   2.5 | -10.7  12.7  300  28 14   7.8   4.3
 16000 -10.7  12.7  310  29 15   5.1   2.8 |  -9.7  14.5  300  28 14   5.9   3.3
 15500  -9.9  14.2  305  30 15   5.0   2.8 |  -8.8  16.2  305  29 15   6.1   3.3
 15000  -9.1  15.6  305  30 16   5.7   3.1 |  -7.9  17.8  305  29 15   5.9   3.2
 14500  -8.2  17.2  300  30 15   5.9   3.2 |  -6.6  20.1  305  29 15   5.9   3.2
 14000  -6.8  19.8  300  29 15   7.2   4.0 |  -5.7  21.7  305  29 15   6.0   3.3
 13500  -5.7  21.7  300  28 14   7.1   3.9 |  -4.8  23.4  300  29 15   5.9   3.2
 13000  -4.6  23.7  300  28 14   7.6   4.2 |  -3.8  25.2  300  29 15   6.7   3.7
 12500  -3.5  25.7  300  27 14   7.7   4.2 |  -2.8  27.0  295  29 15   6.7   3.7
 12000  -2.4  27.7  295  26 13   6.9   3.8 |  -1.9  28.6  295  28 15   6.1   3.4
 11500  -1.4  29.5  295  25 13   7.2   4.0 |  -1.0  30.2  290  27 14   6.2   3.4
 11000  -0.5  31.1  295  24 12   4.6   2.5 |  -0.1  31.8  290  25 13   6.0   3.3
 10500   0.1  32.2  295  21 11   5.3   2.9 |   0.8  33.4  290  22 11   6.7   3.7
 10250   0.4  32.7  295  20 10   2.6   1.4 |   1.2  34.2  285  20 10   3.7   2.0
 10000   0.5  32.9  295  19 10   2.8   1.6 |   1.4  34.5  285  19 10   4.1   2.3
  9750   0.9  33.6  295  16  8   5.7   3.1 |   1.9  35.4  285  17  9   7.5   4.1
  9500   1.2  34.2  295  12  6   5.2   2.9 |   2.4  36.3  285  15  8   6.7   3.7
  9250   1.6  34.9  295   9  5   2.7   1.5 |   2.8  37.0  285  13  7   5.2   2.8
  9000   1.7  35.1  290   6  3   2.3   1.3 |   3.1  37.6  280  11  6   4.4   2.4
  8750   1.9  35.4  270   3  2   5.0   2.8 |   3.5  38.3  275   9  5   5.7   3.2
  8500   2.3  36.1  205   2  1   5.8   3.2 |   4.0  39.2  270   7  4   5.5   3.0
  8250   2.8  37.0  165   3  2   7.5   4.1 |   4.3  39.7  255   5  3   4.7   2.6
  8000   3.4  38.1  155   3  2   8.4   4.6 |   4.6  40.3  235   4  2   4.9   2.7
  7750   4.0  39.2  150   4  2   9.5   5.2 |   5.0  41.0  210   4  2   5.7   3.1
  7500   4.7  40.5  150   4  2  10.2   5.6 |   5.5  41.9  190   3  2   8.0   4.4
  7250   5.5  41.9  150   4  2  10.1   5.6 |   6.2  43.2  185   3  2   9.7   5.3
  7000   6.3  43.3  150   4  2  10.1   5.5 |   6.9  44.4  175   3  1   9.3   5.1
  6750   7.0  44.6  150   4  2   9.6   5.2 |   7.5  45.5  165   2  1   8.9   4.9
  6500   7.7  45.9  150   4  2  10.1   5.5 |   8.2  46.8  155   2  1   9.4   5.1
  6250   8.5  47.3  150   4  2  11.2   6.1 |   8.9  48.0  150   2  1   9.9   5.5
  6000   9.3  48.7  150   3  2   9.5   5.2 |   9.7  49.5  145   2  1   9.8   5.4
  5750  10.0  50.0  150   3  2  12.4   6.8 |  10.4  50.7  135   2  1   8.2   4.5
  5500  11.3  52.3  145   3  2  21.5  11.8 |  10.8  51.4  125   1  1   5.2   2.9
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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