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386
UXUS97 KBOU 201224
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0624 MDT Monday, October 20, 2014

This forecast is for Monday, October 20, 2014:

If the trigger temperature of 71.2 F/21.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 773 ft/min (3.9 m/s)
   Maximum height of thermals.................. 13940 ft MSL (8655 ft AGL)

Forecast maximum temperature................... 75.0 F/24.3 C
Time of trigger temperature.................... 1145 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................. 7687 ft MSL (2402 ft AGL)
Thermal soaring outlook for Tuesday 10/21...... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 13900 ft MSL (8615 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 14392 ft MSL (9107 ft AGL)
Wave soaring outlook for Tuesday 10/21......... Poor

Remarks... None

Sunrise/Sunset.................... 07:15:07 / 18:14:21 MDT
Total possible sunshine........... 10 hr 59 min 14 sec (659 min 14 sec)
Altitude of sun at 12:44:19 MDT... 39.74 degrees

Upper air data from rawinsonde observation taken on 10/20/2014 at 0600 MDT

Freezing level.................. 12852 ft MSL (7567 ft AGL)
Convective condensation level... 16267 ft MSL (10982 ft AGL)
Lifted condensation level....... 15457 ft MSL (10172 ft AGL)
Lifted index.................... +1.3
K index......................... +14.7

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  -66.8 -88.2   350   15    8   6.9   3.8   83.5 182.3    34.5      M    M
 45000  -56.9 -70.4   325   31   16   4.4   2.4   74.2 165.6    31.3      M    M
 40000  -47.2 -53.0   330   22   12   6.1   3.3   66.5 151.8    28.4      M    M
 38000  -43.7 -46.7   330   25   13   5.9   3.2   63.1 145.6    26.8      M    M
 36000  -41.8 -43.2   340   22   11   1.8   1.0   57.3 135.2    23.4      M    M
 34000  -42.6 -44.7   345   16    8   3.8   2.1   48.0 118.4    17.3      M    M
 32000  -41.3 -42.3   345    7    4   4.6   2.5   41.7 107.1    13.1      M    M
 30000  -37.9 -36.2   295    6    3   8.7   4.8   37.5  99.6    10.3      M    M
 29000  -35.3 -31.5   285    3    2   8.7   4.8   37.1  98.7    10.1      M    M
 28000  -32.6 -26.7   245    1    1   9.1   5.0   36.7  98.0     9.9      M    M
 27000  -29.9 -21.8   155    2    1   9.1   5.0   36.4  97.5     9.8      M    M
 26000  -27.2 -17.0   140    5    2   7.9   4.3   36.2  97.1     9.8      M    M
 25000  -25.1 -13.2   135    7    4   7.0   3.9   35.2  95.3     9.1      M    M
 24000  -23.4 -10.1   140    9    4  10.6   5.8   33.7  92.6     7.9      M    M
 23000  -20.9  -5.6   150    8    4   9.3   5.1   33.2  91.7     7.6      M    M
 22000  -18.8  -1.8   160    8    4   6.6   3.6   32.3  90.1     6.9      M    M
 21000  -16.6   2.1   170    9    4   8.0   4.4   31.4  88.6     6.2      M    M
 20000  -14.0   6.8   180    9    5   8.2   4.5   31.0  87.8     6.0      M    M
 19500  -13.0   8.6   180    9    5   4.8   2.6   30.4  86.7     5.5      M    M
 19000  -12.3   9.9   175    9    5   6.8   3.7   29.6  85.2     4.8      M    M
 18500  -11.0  12.2   180    9    4   8.7   4.8   29.4  84.9     4.6      M    M
 18000   -9.7  14.5   185    8    4   8.9   4.9   29.2  84.6     4.5      M    M
 17500   -8.5  16.7   190    8    4   6.1   3.3   28.9  84.1     4.2      M    M
 17000   -7.8  18.0   195    7    4   4.7   2.6   28.2  82.7     3.6      M    M
 16500   -7.2  19.0   200    7    4   4.0   2.2   27.2  80.9     2.7      M    M
 16000   -6.5  20.3   210    7    4   6.3   3.5   26.3  79.4     1.9      M    M
 15500   -5.5  22.1   205    8    4   7.4   4.1   25.9  78.6     1.5      M    M
 15000   -3.8  25.2   200    9    5   7.5   4.1   25.3  77.6     0.9      M    M
 14500   -2.7  27.1   195   10    5   8.0   4.4   25.0  76.9     0.6      M    M
 14000   -2.0  28.4   195   11    6   2.9   1.6   24.3  75.7    -0.1    771  3.9
 13500   -1.5  29.3   190   11    5   7.1   3.9   23.3  74.0    -1.1    743  3.8
 13000   -0.2  31.6   185   10    5   9.0   4.9   23.2  73.8    -1.2    687  3.5
 12500    1.2  34.2   180   10    5   9.1   5.0   23.1  73.7    -1.3    632  3.2
 12000    2.6  36.7   175   10    5   9.1   5.0   23.1  73.5    -1.4    576  2.9
 11500    3.9  39.0   185   11    5   9.1   5.0   22.9  73.3    -1.5    520  2.6
 11000    5.3  41.5   190   11    6   9.1   5.0   22.8  73.1    -1.6    464  2.4
 10500    6.7  44.1   195   12    6   9.3   5.1   22.7  72.9    -1.7    409  2.1
 10250    7.4  45.3   195   12    6   9.6   5.3   22.7  72.9    -1.8    380  1.9
 10000    8.1  46.6   190   12    6  10.1   5.5   22.7  72.9    -1.8    351  1.8
  9750    8.8  47.8   195   12    6   8.9   4.9   22.7  72.9    -1.8    322  1.6
  9500    9.4  48.9   200   11    6   7.7   4.2   22.6  72.7    -1.9    297  1.5
  9250   10.0  50.0   200   11    6   8.0   4.4   22.5  72.4    -2.1    272  1.4
  9000   10.6  51.1   205   11    6   7.9   4.3   22.3  72.2    -2.2    247  1.3
  8750   11.1  52.0   205   11    6   7.9   4.4   22.2  71.9    -2.4    222  1.1
  8500   11.7  53.1   210   10    5   7.9   4.4   22.0  71.7    -2.5    198  1.0
  8250   12.3  54.1   210   10    5   7.9   4.3   21.9  71.4    -2.7    173  0.9
  8000   12.9  55.2   215   10    5   8.0   4.4   21.8  71.2    -2.8    148  0.8
  7750   13.5  56.3   205   11    5   7.7   4.2   21.6  70.9    -3.0    123  0.6
  7500   14.1  57.4   200   11    6   8.8   4.8   21.5  70.7    -3.1     98  0.5
  7250   14.6  58.3   195   12    6   4.7   2.6   21.3  70.4    -3.3     73  0.4
  7000   14.7  58.5   190   13    7   0.3   0.1   20.7  69.3    -3.9     63  0.3
  6750   14.6  58.3   195   11    6  -4.7  -2.6   19.9  67.8    -4.7     58  0.3
  6500   13.8  56.8   205    9    5 -16.9  -9.3   18.3  65.0    -6.3     75  0.4
  6250   12.6  54.7   215    7    4  -9.9  -5.4   16.3  61.4    -8.3    105  0.5
  6000   12.4  54.3   235    6    3   0.8   0.4   15.4  59.8    -9.2    102  0.5
  5750   12.3  54.1   235    4    2  -4.7  -2.6   14.6  58.2   -10.1     99  0.5
  5500   11.4  52.5   235    2    1 -22.1 -12.1   13.0  55.4   -11.7    118  0.6

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

           10/20/2014 at 0900 MDT          |       10/20/2014 at 1200 MDT
                                           |
K index... +20.0  LI... +2.2               | K index... +21.5  LI... +1.6
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 -65.0 -85.0  330  17  9   4.8   2.6 | -64.9 -84.8  325  13  7   5.1   2.8
 45000 -57.5 -71.5  335  20 10   5.8   3.2 | -56.6 -69.9  330  19 10   5.7   3.1
 40000 -48.4 -55.1  340  21 11   4.2   2.3 | -48.1 -54.6  330  16  8   4.2   2.3
 38000 -45.9 -50.6  340  17  9   4.1   2.3 | -45.7 -50.3  330  13  7   4.1   2.3
 36000 -43.4 -46.1  345  12  6   4.2   2.3 | -43.2 -45.8  330  10  5   4.1   2.3
 34000 -41.3 -42.3  355   5  3   3.0   1.7 | -41.0 -41.8  315   3  2   3.3   1.8
 32000 -39.5 -39.1  135   5  2   3.0   1.6 | -39.1 -38.4  180   6  3   3.3   1.8
 30000 -36.5 -33.7  145  10  5   6.6   3.6 | -35.7 -32.3  175  11  6   6.3   3.4
 29000 -34.1 -29.4  150  11  6   6.6   3.6 | -33.8 -28.8  180  11  6   6.3   3.4
 28000 -32.1 -25.8  150  13  6   6.5   3.5 | -31.9 -25.4  185  11  6   6.1   3.4
 27000 -29.9 -21.8  150  13  7   7.6   4.2 | -29.8 -21.6  180  12  6   7.5   4.1
 26000 -27.7 -17.9  150  14  7   7.6   4.2 | -27.5 -17.5  175  14  7   7.5   4.1
 25000 -25.4 -13.7  150  14  7   7.6   4.2 | -25.3 -13.5  175  15  8   7.5   4.1
 24000 -23.1  -9.6  150  14  7   7.9   4.3 | -23.0  -9.4  175  15  8   7.9   4.3
 23000 -20.7  -5.3  155  13  7   7.9   4.3 | -20.6  -5.1  175  14  7   8.0   4.4
 22000 -18.4  -1.1  160  13  7   7.9   4.4 | -18.2  -0.8  180  13  7   8.0   4.4
 21000 -16.1   3.0  160  12  6   7.6   4.2 | -16.0   3.2  180  13  6   7.0   3.9
 20000 -13.8   7.2  165  11  6   7.6   4.2 | -14.0   6.8  180  12  6   7.0   3.9
 19500 -12.7   9.1  165  11  6   7.5   4.1 | -12.9   8.8  185  12  6   7.0   3.8
 19000 -11.5  11.3  165  10  5   6.6   3.6 | -11.9  10.6  185  11  6   6.1   3.3
 18500 -10.7  12.7  170   9  5   5.7   3.1 | -11.2  11.8  185  10  5   5.0   2.7
 18000  -9.9  14.2  175   7  4   5.7   3.1 | -10.4  13.3  190   8  4   4.7   2.6
 17500  -9.0  15.8  185   6  3   6.2   3.4 |  -9.6  14.7  190   6  3   6.7   3.7
 17000  -8.2  17.2  205   4  2   6.2   3.4 |  -8.7  16.3  195   5  3   6.6   3.6
 16500  -7.3  18.9  235   4  2   6.5   3.6 |  -7.8  18.0  205   4  2   7.1   3.9
 16000  -6.3  20.7  240   4  2   6.7   3.7 |  -6.7  19.9  210   5  2   7.3   4.0
 15500  -5.4  22.3  245   5  2   6.7   3.7 |  -5.6  21.9  210   5  3   7.4   4.1
 15000  -4.4  24.1  235   6  3   6.8   3.8 |  -4.0  24.8  210   7  4   7.5   4.1
 14500  -2.9  26.8  230   7  4   7.4   4.0 |  -2.9  26.8  210   9  5   7.9   4.3
 14000  -1.8  28.8  225   8  4   7.8   4.3 |  -1.7  28.9  210  10  5   8.2   4.5
 13500  -0.7  30.7  220   8  4   7.9   4.3 |  -0.5  31.1  210  11  6   8.2   4.5
 13000   0.4  32.7  215   9  5   8.0   4.4 |   0.7  33.3  210  11  6   8.2   4.5
 12500   1.6  34.9  215   9  5   8.0   4.4 |   1.9  35.4  210  12  6   8.3   4.6
 12000   2.8  37.0  215  10  5   8.1   4.4 |   3.2  37.8  210  13  7   8.7   4.8
 11500   4.0  39.2  210  10  5   8.2   4.5 |   4.5  40.1  210  14  7   8.7   4.8
 11000   5.3  41.5  210  10  5   8.7   4.8 |   5.7  42.3  210  14  7   8.4   4.6
 10500   6.6  43.9  215  10  5   6.7   3.7 |   7.0  44.6  210  15  8   5.8   3.2
 10250   7.0  44.6  215  11  5   5.4   2.9 |   7.3  45.1  210  15  8   5.1   2.8
 10000   7.5  45.5  210  11  6   9.4   5.2 |   7.9  46.2  210  15  8  10.2   5.6
  9750   8.3  46.9  210  11  6  11.2   6.2 |   8.7  47.7  210  16  8  11.5   6.3
  9500   9.1  48.4  210  11  6   9.3   5.1 |   9.5  49.1  210  16  8   9.8   5.4
  9250   9.6  49.3  210  12  6   5.6   3.1 |  10.2  50.4  210  16  8   6.5   3.6
  9000  10.1  50.2  210  12  6   7.3   4.0 |  10.6  51.1  210  16  8   7.4   4.1
  8750  10.8  51.4  210  12  6  10.1   5.5 |  11.3  52.3  205  16  8   9.3   5.1
  8500  11.5  52.7  210  13  6   8.5   4.7 |  12.0  53.6  205  16  8   8.2   4.5
  8250  12.1  53.8  210  13  7   7.6   4.2 |  12.5  54.5  205  16  8   7.5   4.1
  8000  12.6  54.7  215  14  7   7.4   4.1 |  13.1  55.6  205  16  8   7.3   4.0
  7750  13.2  55.8  215  14  7   6.9   3.8 |  13.7  56.7  205  16  8   7.1   3.9
  7500  13.7  56.7  215  15  8   6.8   3.8 |  14.2  57.6  205  16  8   6.5   3.6
  7250  14.2  57.6  215  15  8   6.4   3.5 |  14.6  58.3  200  15  8   6.1   3.3
  7000  14.7  58.5  215  15  8   8.0   4.4 |  15.0  59.0  195  14  7   6.0   3.3
  6750  15.3  59.5  215  15  8   4.5   2.5 |  15.4  59.7  190  13  7   6.9   3.8
  6500  15.2  59.4  215  15  8  -4.3  -2.4 |  16.0  60.8  185  12  6   9.0   4.9
  6250  14.7  58.5  215  14  7  -9.8  -5.4 |  16.7  62.1  185  11  5  10.1   5.5
  6000  14.1  57.4  215  13  7   0.6   0.3 |  17.4  63.3  185   9  5   8.2   4.5
  5750  14.4  57.9  215  13  7  -5.1  -2.8 |  18.0  64.4  180   9  4  11.5   6.3
  5500  12.5  54.5  210   9  5 -42.0 -23.0 |  19.3  66.7  180   8  4  21.7  11.9

           10/20/2014 at 1500 MDT          |       10/20/2014 at 1800 MDT
                                           |
K index... +19.8  LI... +0.3               | K index... +19.8  LI... +0.4
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 -65.6 -86.1  305   9  5   5.4   2.9 | -65.8 -86.4  270  12  6   5.3   2.9
 45000 -56.9 -70.4  315  17  9   6.0   3.3 | -57.7 -71.9  290  17  9   5.9   3.2
 40000 -48.0 -54.4  305  19 10   5.1   2.8 | -48.5 -55.3  290  19 10   5.2   2.9
 38000 -45.0 -49.0  310  15  8   5.1   2.8 | -45.3 -49.5  290  15  8   5.3   2.9
 36000 -41.9 -43.4  315  12  6   5.2   2.8 | -42.2 -44.0  285  11  6   5.3   2.9
 34000 -39.8 -39.6  295   6  3   2.4   1.3 | -40.0 -40.0  260   9  5   2.5   1.4
 32000 -38.3 -36.9  200   7  4   2.4   1.3 | -38.5 -37.3  225  12  6   2.5   1.4
 30000 -35.4 -31.7  195  10  5   5.6   3.1 | -35.8 -32.4  225  13  7   6.4   3.5
 29000 -33.8 -28.8  205  10  5   5.6   3.1 | -33.4 -28.1  235  11  6   6.5   3.5
 28000 -32.1 -25.8  215   9  5   5.4   3.0 | -31.4 -24.5  250  11  5   6.3   3.5
 27000 -30.0 -22.0  215  10  5   7.6   4.2 | -29.2 -20.6  245  10  5   7.7   4.2
 26000 -27.7 -17.9  210  11  6   7.6   4.2 | -27.0 -16.6  240  10  5   7.7   4.2
 25000 -25.4 -13.7  205  12  6   7.6   4.2 | -24.7 -12.5  230  11  5   7.7   4.2
 24000 -23.1  -9.6  205  13  7   7.9   4.3 | -22.4  -8.3  225  11  6   7.6   4.2
 23000 -20.8  -5.4  205  14  7   7.9   4.3 | -20.1  -4.2  225  11  6   7.6   4.2
 22000 -18.4  -1.1  205  14  7   8.0   4.4 | -17.9  -0.2  220  11  6   7.7   4.2
 21000 -16.3   2.7  210  14  7   6.6   3.6 | -15.9   3.4  225  11  6   6.1   3.3
 20000 -14.4   6.1  210  13  7   6.5   3.6 | -14.1   6.6  225  10  5   6.1   3.3
 19500 -13.4   7.9  215  12  6   6.5   3.6 | -13.3   8.1  230  10  5   6.2   3.4
 19000 -12.4   9.7  215  12  6   6.4   3.5 | -12.4   9.7  230   9  5   6.6   3.6
 18500 -11.5  11.3  220  11  5   6.2   3.4 | -11.3  11.7  235   9  4   7.2   4.0
 18000 -10.6  12.9  230   9  5   6.0   3.3 | -10.3  13.5  235   8  4   7.3   4.0
 17500  -9.6  14.7  230   9  4   7.8   4.3 |  -9.2  15.4  235   7  4   6.8   3.7
 17000  -8.5  16.7  225   8  4   7.8   4.3 |  -8.2  17.2  230   6  3   6.9   3.8
 16500  -7.4  18.7  225   7  4   7.8   4.3 |  -7.2  19.0  225   5  3   7.1   3.9
 16000  -6.2  20.8  220   7  4   7.8   4.3 |  -6.1  21.0  220   5  3   7.2   4.0
 15500  -5.1  22.8  220   7  4   7.8   4.3 |  -5.1  22.8  215   5  3   7.3   4.0
 15000  -3.4  25.9  215   8  4   7.9   4.3 |  -3.9  25.0  215   5  3   8.1   4.4
 14500  -2.2  28.0  210   9  5   7.9   4.4 |  -2.2  28.0  220   6  3   8.0   4.4
 14000  -1.0  30.2  210   9  5   8.0   4.4 |  -1.0  30.2  225   6  3   8.0   4.4
 13500   0.1  32.2  205  10  5   8.0   4.4 |   0.2  32.4  235   6  3   8.1   4.5
 13000   1.4  34.5  205  10  5   8.2   4.5 |   1.4  34.5  240   6  3   8.6   4.7
 12500   2.6  36.7  205  11  5   8.3   4.5 |   2.6  36.7  240   7  3   8.5   4.7
 12000   3.8  38.8  205  11  6   8.8   4.8 |   3.8  38.8  235   7  4   7.9   4.4
 11500   5.1  41.2  205  12  6   8.7   4.8 |   4.9  40.8  230   8  4   8.0   4.4
 11000   6.3  43.3  210  12  6   7.5   4.1 |   6.2  43.2  225   8  4   8.5   4.7
 10500   7.4  45.3  210  13  7   5.8   3.2 |   7.5  45.5  220   8  4   6.0   3.3
 10250   7.7  45.9  210  13  7   5.8   3.2 |   7.8  46.0  215   8  4   5.7   3.1
 10000   8.3  46.9  205  13  6   9.1   5.0 |   8.4  47.1  210   8  4  10.3   5.7
  9750   9.0  48.2  200  12  6   9.1   5.0 |   9.2  48.6  210   8  4  10.7   5.9
  9500   9.6  49.3  190  12  6   8.9   4.9 |  10.0  50.0  205   8  4  10.1   5.5
  9250  10.2  50.4  185  12  6   8.4   4.6 |  10.7  51.3  200   8  4   8.0   4.4
  9000  10.9  51.6  185  12  6   9.4   5.1 |  11.3  52.3  195   9  5   7.9   4.3
  8750  11.6  52.9  185  12  6  10.2   5.6 |  11.9  53.4  190  11  6   9.0   5.0
  8500  12.4  54.3  180  12  6  10.1   5.5 |  12.6  54.7  185  12  6   8.2   4.5
  8250  13.1  55.6  180  12  6  10.6   5.8 |  13.2  55.8  185  14  7   7.1   3.9
  8000  13.9  57.0  180  11  6  10.1   5.5 |  13.7  56.7  180  16  8   6.8   3.7
  7750  14.6  58.3  180  11  6   9.2   5.0 |  14.2  57.6  180  17  9   6.2   3.4
  7500  15.3  59.5  180  11  6   9.6   5.3 |  14.6  58.3  175  17  9   7.8   4.3
  7250  16.1  61.0  180  11  6  10.0   5.5 |  15.3  59.5  175  17  9   9.7   5.3
  7000  16.8  62.2  180  11  6  10.0   5.5 |  16.0  60.8  175  17  9   9.2   5.1
  6750  17.6  63.7  180  11  6  10.4   5.7 |  16.7  62.1  175  17  9   8.8   4.8
  6500  18.3  64.9  180  11  6  10.4   5.7 |  17.3  63.1  175  16  8   9.1   5.0
  6250  19.1  66.4  180  11  5  10.7   5.9 |  18.0  64.4  175  15  8   9.3   5.1
  6000  19.9  67.8  180  10  5   9.5   5.2 |  18.7  65.7  170  14  7  10.1   5.5
  5750  20.6  69.1  180  10  5  11.5   6.3 |  19.4  66.9  170  14  7   7.2   4.0
  5500  21.7  71.1  180  10  5  18.9  10.4 |  19.5  67.1  170  10  5  -0.5  -0.3
________________________________________________________________________________

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

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

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

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

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

DEFINITIONS:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

042613




U.S. Dept. of Commerce
NOAA National Weather Service
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Silver Spring, MD 20910
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Page last modified: May 16, 2007
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