Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 210028
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0028 UTC Monday, April 21, 2014

This forecast is for Monday, April 21, 2014:

If the trigger temperature of 56.3 F/13.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 869 ft/min (4.4 m/s)
   Maximum height of thermals.................. 15895 ft MSL (10608 ft AGL)

Forecast maximum temperature................... 69.0 F/21.0 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12466 ft MSL (7178 ft AGL)
Thermal soaring outlook for Tuesday 04/22...... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 39519 ft MSL (34232 ft AGL)
Wave soaring outlook for Tuesday 04/22......... Poor

Remarks...

Sunrise/Sunset.................... 06:13:16 / 19:42:47 MST
Total possible sunshine........... 13 hr 29 min 32 sec (809 min 32 sec)
Altitude of sun at 12:58:12 MST... 62.26 degrees

Upper air data from numerical model forecast valid on 04/21/2014 at 0500 MST

Freezing level.................. 10094 ft MSL (4807 ft AGL)
Convective condensation level... 11727 ft MSL (6440 ft AGL)
Lifted condensation level....... 13395 ft MSL (8108 ft AGL)
Lifted index.................... -2.1
K index......................... +24.7

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  -60.9 -77.6   275   24   12   1.0   0.5      M     M       M      M    M
 45000  -59.5 -75.1   290   30   16  -0.3  -0.1      M     M       M      M    M
 40000  -59.7 -75.5   295   38   20  -0.1  -0.1      M     M       M      M    M
 38000  -57.6 -71.7   300   40   20   5.3   2.9      M     M       M      M    M
 36000  -54.4 -65.9   300   40   21   5.3   2.9      M     M       M      M    M
 34000  -50.7 -59.3   300   39   20   7.8   4.3      M     M       M      M    M
 32000  -45.5 -49.9   305   38   20   7.8   4.3      M     M       M      M    M
 30000  -41.0 -41.8   305   36   19   6.8   3.7   35.1  95.2    11.0      M    M
 29000  -39.0 -38.2   305   35   18   6.8   3.7   33.9  93.1    10.2      M    M
 28000  -37.0 -34.6   305   35   18   6.8   3.7   32.9  91.2     9.5      M    M
 27000  -34.9 -30.8   305   33   17   7.3   4.0   31.9  89.3     8.8      M    M
 26000  -32.7 -26.9   305   30   15   7.3   4.0   30.8  87.5     8.1      M    M
 25000  -30.5 -22.9   300   27   14   7.3   4.0   30.0  85.9     7.5      M    M
 24000  -28.4 -19.1   300   24   12   6.0   3.3   29.0  84.2     6.8      M    M
 23000  -26.5 -15.7   300   21   11   6.1   3.4   27.6  81.7     5.7      M    M
 22000  -24.7 -12.5   305   19   10   6.2   3.4   26.3  79.4     4.7      M    M
 21000  -22.8  -9.0   305   18    9   7.4   4.0   25.3  77.5     3.8      M    M
 20000  -20.6  -5.1   300   17    9   7.4   4.0   24.3  75.8     3.1      M    M
 19500  -19.5  -3.1   300   17    9   7.4   4.1   23.9  75.1     2.7      M    M
 19000  -18.4  -1.1   295   17    9   7.4   4.1   23.6  74.4     2.4      M    M
 18500  -17.3   0.9   295   16    8   8.2   4.5   23.3  73.9     2.1      M    M
 18000  -16.1   3.0   300   15    8   8.2   4.5   23.0  73.4     1.8      M    M
 17500  -14.9   5.2   300   15    7   7.2   4.0   22.7  72.8     1.6      M    M
 17000  -13.9   7.0   300   13    7   6.9   3.8   22.2  71.9     1.1      M    M
 16500  -12.9   8.8   300   12    6   6.9   3.8   21.7  71.0     0.7      M    M
 16000  -11.9  10.6   300   11    6   6.9   3.8   21.2  70.2     0.2      M    M
 15500  -10.4  13.3   300    9    5   7.3   4.0   20.5  68.9    -0.4    822  4.2
 15000   -9.3  15.3   300    9    5   7.5   4.1   20.1  68.2    -0.8    774  3.9
 14500   -8.2  17.2   300   10    5   7.3   4.0   19.8  67.6    -1.2    726  3.7
 14000   -7.1  19.2   300    9    5   7.0   3.8   19.3  66.7    -1.6    680  3.5
 13500   -6.1  21.0   295    8    4   7.0   3.8   18.9  65.9    -2.1    635  3.2
 13000   -5.1  22.8   295    8    4   6.9   3.8   18.4  65.1    -2.6    590  3.0
 12500   -4.1  24.6   295    8    4   6.9   3.8   17.9  64.3    -3.0    546  2.8
 12000   -3.1  26.4   300    7    4   6.7   3.7   17.4  63.4    -3.5    502  2.5
 11500   -2.2  28.0   300    7    4   6.6   3.6   17.0  62.5    -4.1    458  2.3
 11000   -1.3  29.7   310    6    3   5.8   3.2   16.4  61.5    -4.7    418  2.1
 10500   -0.5  31.1   320    5    3   5.7   3.1   15.8  60.4    -5.3    378  1.9
 10250   -0.1  31.8   325    5    2   4.0   2.2   15.4  59.7    -5.7    360  1.8
 10000    0.2  32.4   330    5    2   5.7   3.1   15.0  58.9    -6.2    344  1.7
  9750    0.7  33.3   340    5    2   8.2   4.5   14.8  58.6    -6.4    320  1.6
  9500    1.3  34.3   345    5    2   7.0   3.9   14.6  58.3    -6.6    295  1.5
  9250    1.8  35.2   355    5    2   6.5   3.5   14.4  57.9    -6.8    273  1.4
  9000    2.2  36.0   360    4    2   6.3   3.4   14.1  57.4    -7.1    252  1.3
  8750    2.7  36.9   010    4    2   6.4   3.5   13.8  56.9    -7.4    230  1.2
  8500    3.2  37.8   020    4    2   4.6   2.5   13.5  56.4    -7.7    209  1.1
  8250    3.4  38.1   030    5    3   2.9   1.6   13.0  55.5    -8.1    194  1.0
  8000    3.7  38.7   035    7    3   3.7   2.1   12.5  54.6    -8.6    178  0.9
  7750    4.0  39.2   035    8    4   5.0   2.8   12.1  53.8    -9.0    161  0.8
  7500    4.4  39.9   035    9    5   4.5   2.5   11.8  53.2    -9.4    142  0.7
  7250    4.7  40.5   035   10    5   3.0   1.6   11.3  52.3    -9.9    126  0.6
  7000    5.0  41.0   035   11    6   4.5   2.5   10.8  51.5   -10.4    110  0.6
  6750    5.4  41.7   035   12    6   7.7   4.3   10.5  51.0   -10.7     90  0.5
  6500    6.1  43.0   030   12    6   8.6   4.7   10.4  50.8   -10.8     63  0.3
  6250    6.7  44.1   025   12    6   9.3   5.1   10.4  50.6   -10.9     37  0.2
  6000    7.3  45.1   025   12    6   5.9   3.2   10.3  50.5   -11.0     11  0.1
  5750    7.5  45.5   025   10    5   1.3   0.7    9.8  49.6   -11.6      M    M
  5500    7.6  45.7   020    7    3   4.0   2.2    9.2  48.6   -12.3      M    M

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

           04/21/2014 at 0800 MST          |       04/21/2014 at 1100 MST
                                           |
K index... +20.6  LI... +1.2               | K index... +15.3  LI... +1.7
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.9
                                           |
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 -61.5 -78.7  280  27 14   0.9   0.5 | -61.3 -78.3  290  32 17   1.1   0.6
 45000 -60.1 -76.2  295  33 17   0.2   0.1 | -59.7 -75.5  295  40 21  -1.2  -0.7
 40000 -59.8 -75.6  305  37 19   0.3   0.2 | -61.4 -78.5  315  44 22  -0.9  -0.5
 38000 -57.9 -72.2  310  36 19   4.4   2.4 | -59.0 -74.2  315  44 23   6.1   3.4
 36000 -55.2 -67.4  315  36 19   4.4   2.4 | -55.3 -67.5  315  43 22   6.1   3.4
 34000 -51.7 -61.1  320  37 19   8.7   4.8 | -51.1 -60.0  315  41 21   8.5   4.7
 32000 -46.5 -51.7  325  38 20   8.7   4.8 | -45.3 -49.5  320  37 19   8.5   4.7
 30000 -40.6 -41.1  325  38 19   8.8   4.8 | -40.3 -40.5  320  34 18   8.5   4.6
 29000 -37.9 -36.2  325  37 19   8.8   4.8 | -37.7 -35.9  320  33 17   8.5   4.6
 28000 -35.3 -31.5  325  36 18   8.7   4.8 | -35.2 -31.4  320  32 16   8.4   4.6
 27000 -33.0 -27.4  325  34 18   6.3   3.4 | -32.8 -27.0  320  30 16   7.1   3.9
 26000 -31.1 -24.0  325  32 16   6.3   3.5 | -30.7 -23.3  320  28 14   7.0   3.9
 25000 -29.2 -20.6  320  30 15   6.3   3.5 | -28.6 -19.5  320  26 13   7.0   3.9
 24000 -27.3 -17.1  320  28 14   6.3   3.5 | -26.6 -15.9  320  25 13   5.9   3.2
 23000 -25.4 -13.7  315  27 14   6.3   3.5 | -24.8 -12.6  320  24 13   6.0   3.3
 22000 -23.5 -10.3  310  25 13   6.3   3.5 | -23.0  -9.4  315  24 12   6.0   3.3
 21000 -21.6  -6.9  310  24 12   6.7   3.7 | -21.1  -6.0  315  23 12   6.9   3.8
 20000 -19.6  -3.3  305  21 11   6.8   3.7 | -19.0  -2.2  310  22 11   6.9   3.8
 19500 -18.6  -1.5  305  20 10   6.8   3.7 | -17.9  -0.2  310  21 11   6.9   3.8
 19000 -17.6   0.3  300  19 10   6.8   3.7 | -16.9   1.6  310  20 10   6.9   3.8
 18500 -16.6   2.1  300  18  9   6.1   3.3 | -15.9   3.4  305  19 10   6.5   3.6
 18000 -15.7   3.7  295  17  9   6.1   3.4 | -14.9   5.2  305  18  9   6.5   3.6
 17500 -14.8   5.4  290  17  9   7.4   4.1 | -14.0   6.8  300  17  9   6.4   3.5
 17000 -13.7   7.3  285  16  8   7.8   4.3 | -13.0   8.6  290  16  8   6.4   3.5
 16500 -12.5   9.5  285  15  8   7.7   4.2 | -12.1  10.2  285  16  8   6.5   3.6
 16000 -11.4  11.5  285  15  8   7.3   4.0 | -10.7  12.7  280  15  8   6.7   3.7
 15500  -9.9  14.2  290  14  7   7.2   3.9 |  -9.7  14.5  275  15  8   7.6   4.2
 15000  -8.8  16.2  290  13  7   7.1   3.9 |  -8.5  16.7  275  15  7   8.1   4.5
 14500  -7.8  18.0  290  13  6   7.2   3.9 |  -7.4  18.7  275  14  7   8.3   4.5
 14000  -6.7  19.9  290  12  6   7.3   4.0 |  -6.1  21.0  275  14  7   8.4   4.6
 13500  -5.7  21.7  285  11  6   7.3   4.0 |  -4.9  23.2  275  13  7   8.3   4.5
 13000  -4.6  23.7  285  10  5   7.1   3.9 |  -3.7  25.3  270  13  7   7.9   4.3
 12500  -3.6  25.5  280  10  5   7.0   3.9 |  -2.6  27.3  270  12  6   7.8   4.3
 12000  -2.6  27.3  275   9  5   6.7   3.7 |  -1.5  29.3  265  12  6   7.4   4.1
 11500  -1.6  29.1  270   8  4   6.5   3.5 |  -0.4  31.3  260  11  6   7.3   4.0
 11000  -0.9  30.4  260   7  4   4.5   2.5 |   0.5  32.9  250  11  6   6.0   3.3
 10500  -0.2  31.6  250   6  3   4.3   2.4 |   1.4  34.5  245  10  5   5.6   3.1
 10250   0.0  32.0  250   5  3   2.5   1.4 |   1.8  35.2  240  10  5   3.9   2.2
 10000   0.2  32.4  245   5  2   3.9   2.1 |   2.0  35.6  240  10  5   4.6   2.5
  9750   0.6  33.1  245   4  2   6.1   3.3 |   2.4  36.3  235   9  5   6.1   3.3
  9500   1.0  33.8  245   3  1   4.8   2.6 |   2.8  37.0  225   8  4   4.7   2.6
  9250   1.3  34.3  250   2  1   3.7   2.0 |   3.1  37.6  220   7  4   3.1   1.7
  9000   1.5  34.7  250   2  1   3.9   2.2 |   3.3  37.9  215   6  3   3.4   1.9
  8750   1.9  35.4  260   1  1   4.8   2.6 |   3.6  38.5  195   4  2   3.9   2.1
  8500   2.2  36.0  000   0  0   4.7   2.6 |   3.9  39.0  165   3  2   5.2   2.8
  8250   2.6  36.7  085   1  1   4.3   2.4 |   4.3  39.7  150   3  2   5.9   3.2
  8000   2.9  37.2  090   3  1   4.6   2.5 |   4.7  40.5  135   3  2   6.3   3.5
  7750   3.4  38.1  090   4  2   5.9   3.2 |   5.3  41.5  125   4  2   9.2   5.1
  7500   3.8  38.8  090   4  2   6.2   3.4 |   6.1  43.0  125   4  2  10.4   5.7
  7250   4.3  39.7  090   3  2   5.8   3.2 |   6.8  44.2  120   4  2   9.6   5.3
  7000   4.7  40.5  090   2  1   5.7   3.1 |   7.5  45.5  120   4  2  10.4   5.7
  6750   5.2  41.4  090   2  1   8.3   4.6 |   8.3  46.9  120   3  2  10.7   5.9
  6500   5.9  42.6  090   2  1  10.6   5.8 |   9.1  48.4  120   3  2  10.3   5.7
  6250   6.7  44.1  085   2  1  10.0   5.5 |   9.9  49.8  115   3  2  10.3   5.7
  6000   7.4  45.3  085   1  1  10.1   5.5 |  10.7  51.3  115   3  2  10.7   5.9
  5750   8.2  46.8  080   1  1  13.3   7.3 |  11.6  52.9  115   3  2  17.0   9.3
  5500   9.4  48.9  075   1  1  18.9  10.4 |  13.2  55.8  110   3  2  25.9  14.2

           04/21/2014 at 1400 MST          |       04/21/2014 at 1700 MST
                                           |
K index... +19.0  LI... -0.4               | K index... +22.7  LI... -0.5
CAPE... +32.8  CIN... -43.6                | CAPE... +78.2  CIN... -25.1
                                           |
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 -62.4 -80.3  290  35 18   0.9   0.5 | -63.2 -81.8  295  31 16   0.4   0.2
 45000 -61.2 -78.2  295  44 23  -0.7  -0.4 | -62.6 -80.7  295  44 23   0.3   0.2
 40000 -62.1 -79.8  320  63 32  -0.4  -0.2 | -62.1 -79.8  315  67 35   0.4   0.2
 38000 -59.0 -74.2  320  60 31   7.2   4.0 | -58.6 -73.5  315  64 33   7.6   4.2
 36000 -54.7 -66.5  315  54 28   7.2   4.0 | -54.0 -65.2  310  58 30   7.6   4.2
 34000 -50.2 -58.4  315  48 25   8.1   4.4 | -49.3 -56.7  310  52 27   8.1   4.5
 32000 -44.7 -48.5  310  42 22   8.0   4.4 | -43.8 -46.8  305  46 24   8.1   4.5
 30000 -39.8 -39.6  305  38 19   8.3   4.6 | -39.0 -38.2  300  41 21   7.7   4.2
 29000 -37.3 -35.1  305  36 19   8.3   4.6 | -36.7 -34.1  300  39 20   7.7   4.2
 28000 -34.8 -30.6  305  34 18   8.3   4.5 | -34.4 -29.9  295  36 19   7.7   4.2
 27000 -32.5 -26.5  305  32 17   7.2   3.9 | -32.2 -26.0  295  34 17   7.2   4.0
 26000 -30.4 -22.7  305  30 15   7.2   3.9 | -30.0 -22.0  295  31 16   7.2   3.9
 25000 -28.2 -18.8  310  28 14   7.2   3.9 | -27.8 -18.0  295  28 15   7.2   3.9
 24000 -26.2 -15.2  310  26 13   6.1   3.3 | -25.7 -14.3  295  26 14   6.6   3.6
 23000 -24.3 -11.7  310  25 13   6.2   3.4 | -23.7 -10.7  300  26 13   6.7   3.7
 22000 -22.5  -8.5  305  24 12   6.2   3.4 | -21.7  -7.1  300  26 13   6.7   3.7
 21000 -20.5  -4.9  305  23 12   6.7   3.7 | -19.7  -3.5  300  25 13   7.3   4.0
 20000 -18.5  -1.3  305  22 11   6.7   3.7 | -17.5   0.5  300  24 12   7.3   4.0
 19500 -17.5   0.5  305  22 11   6.7   3.7 | -16.4   2.5  295  23 12   7.3   4.0
 19000 -16.5   2.3  305  21 11   6.7   3.7 | -15.3   4.5  295  22 11   7.0   3.9
 18500 -15.5   4.1  300  21 11   6.6   3.6 | -14.4   6.1  295  22 11   5.4   3.0
 18000 -14.5   5.9  300  21 11   6.6   3.6 | -13.6   7.5  295  22 12   5.5   3.0
 17500 -13.5   7.7  300  21 11   7.1   3.9 | -12.7   9.1  290  23 12   5.7   3.1
 17000 -12.5   9.5  295  21 11   7.2   4.0 | -11.9  10.6  290  23 12   5.9   3.2
 16500 -11.4  11.5  295  21 11   7.3   4.0 | -11.1  12.0  285  23 12   6.3   3.5
 16000  -9.8  14.4  290  21 11   7.4   4.1 |  -9.6  14.7  285  22 11   7.2   3.9
 15500  -8.8  16.2  285  21 11   7.4   4.1 |  -8.6  16.5  280  21 11   8.7   4.8
 15000  -7.8  18.0  275  20 10   7.5   4.1 |  -7.2  19.0  275  20 10   9.4   5.2
 14500  -6.8  19.8  270  20 10   8.1   4.4 |  -5.8  21.6  275  18  9   9.3   5.1
 14000  -5.5  22.1  265  19 10   8.7   4.8 |  -4.5  23.9  265  17  9   8.9   4.9
 13500  -4.2  24.4  265  18  9   8.7   4.8 |  -3.2  26.2  260  15  8   8.7   4.8
 13000  -2.9  26.8  260  17  9   8.7   4.8 |  -2.1  28.2  245  14  7   7.5   4.1
 12500  -1.7  28.9  255  16  8   8.6   4.7 |  -1.0  30.2  230  14  7   7.6   4.1
 12000  -0.5  31.1  250  16  8   7.7   4.2 |   0.1  32.2  215  13  7   6.9   3.8
 11500   0.6  33.1  245  15  8   7.6   4.2 |   1.1  34.0  205  13  7   7.1   3.9
 11000   1.7  35.1  235  14  7   6.8   3.8 |   2.2  36.0  195  12  6   8.5   4.7
 10500   2.7  36.9  215  13  7   5.7   3.1 |   3.5  38.3  185  11  6   6.8   3.8
 10250   3.0  37.4  210  13  7   2.9   1.6 |   3.9  39.0  180  10  5   4.9   2.7
 10000   3.3  37.9  205  12  6   5.2   2.8 |   4.4  39.9  180  10  5   9.5   5.2
  9750   3.8  38.8  190  10  5   7.4   4.0 |   5.2  41.4  180   9  5  12.5   6.8
  9500   4.2  39.6  170   8  4   6.8   3.7 |   6.1  43.0  175   9  5  10.5   5.8
  9250   4.7  40.5  160   8  4   6.3   3.4 |   6.8  44.2  175   8  4   7.3   4.0
  9000   5.2  41.4  155   8  4   8.1   4.5 |   7.3  45.1  170   8  4   8.9   4.9
  8750   5.9  42.6  155   8  4  10.4   5.7 |   8.1  46.6  170   8  4  11.6   6.4
  8500   6.7  44.1  150   7  4  10.0   5.5 |   8.9  48.0  165   7  4  10.3   5.6
  8250   7.4  45.3  150   7  4   9.8   5.4 |   9.6  49.3  165   7  4   9.7   5.3
  8000   8.2  46.8  150   7  4  10.1   5.5 |  10.4  50.7  165   7  3   9.6   5.3
  7750   8.9  48.0  150   7  4  10.5   5.8 |  11.1  52.0  165   6  3   9.4   5.2
  7500   9.7  49.5  150   7  4  10.2   5.6 |  11.8  53.2  165   6  3   9.8   5.4
  7250  10.5  50.9  150   7  3  10.0   5.5 |  12.6  54.7  165   6  3  10.3   5.7
  7000  11.2  52.2  150   6  3   9.7   5.3 |  13.3  55.9  165   5  3   9.8   5.4
  6750  11.9  53.4  150   6  3   9.8   5.4 |  14.0  57.2  165   5  3   9.3   5.1
  6500  12.7  54.9  150   6  3  10.5   5.8 |  14.7  58.5  160   5  3  10.0   5.5
  6250  13.5  56.3  145   6  3  10.0   5.5 |  15.5  59.9  160   5  2  10.3   5.6
  6000  14.2  57.6  145   6  3  12.0   6.6 |  16.3  61.3  160   4  2  10.6   5.8
  5750  15.3  59.5  145   6  3  17.9   9.8 |  17.1  62.8  160   4  2  12.4   6.8
  5500  16.8  62.2  145   5  3  21.8  11.9 |  18.1  64.6  155   4  2  13.8   7.6
________________________________________________________________________________

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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