Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 291236
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0636 MDT Wednesday, July 29, 2015

This forecast is for Wednesday, July 29, 2015:

If the trigger temperature of 75.6 F/24.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 421 ft/min (2.1 m/s)
   Maximum height of thermals.................. 13274 ft MSL (7989 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11696 ft MSL (6410 ft AGL)
Thermal soaring outlook for Thursday 07/30..... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No changes
Height of stable layer (12-18K ft MSL)......... 13894 ft MSL (8609 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 15862 ft MSL (10577 ft AGL)
Wave soaring outlook for Thursday 07/30........ Poor

Remarks...

Sunrise/Sunset.................... 05:55:34 / 20:16:36 MDT
Total possible sunshine........... 14 hr 21 min 2 sec (861 min 2 sec)
Altitude of sun at 13:05:53 MDT... 68.89 degrees

Upper air data from rawinsonde observation taken on 07/29/2015 at 0600 MDT

Freezing level.................. 15832 ft MSL (10547 ft AGL)
Convective condensation level... 16414 ft MSL (11129 ft AGL)
Lifted condensation level....... 15389 ft MSL (10104 ft AGL)
Lifted index.................... +0.0
K index......................... +19.5

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  -66.8 -88.2   250   36   18   2.5   1.4   81.4 178.5    30.6      M    M
 45000  -63.1 -81.6   230   64   33   3.2   1.7   62.2 143.9    20.9      M    M
 40000  -50.0 -58.0   225   67   35   8.5   4.7   59.8 139.7    20.8      M    M
 38000  -45.1 -49.2   230   68   35   7.9   4.3   58.4 137.0    20.3      M    M
 36000  -40.5 -40.9   235   66   34   7.3   4.0   56.6 133.9    19.6      M    M
 34000  -37.1 -34.8   240   64   33   8.2   4.5   53.2 127.7    17.5      M    M
 32000  -32.4 -26.3   245   61   32   5.0   2.7   51.7 125.1    16.9      M    M
 30000  -27.9 -18.2   240   52   27   6.1   3.4   48.8 119.8    15.2      M    M
 29000  -26.1 -15.0   240   47   24   6.2   3.4   47.4 117.2    14.2      M    M
 28000  -24.3 -11.7   240   43   22   0.8   0.4   45.9 114.6    13.3      M    M
 27000  -23.3  -9.9   240   39   20   8.2   4.5   43.5 110.3    11.5      M    M
 26000  -21.2  -6.2   245   35   18   6.7   3.7   42.5 108.5    10.9      M    M
 25000  -19.2  -2.6   245   31   16   6.8   3.7   41.4 106.5    10.1      M    M
 24000  -17.2   1.0   245   30   15   5.1   2.8   40.1 104.2     9.2      M    M
 23000  -15.6   3.9   245   29   15   5.3   2.9   38.4 101.1     7.9      M    M
 22000  -14.1   6.6   245   28   14   5.3   2.9   36.8  98.3     6.6      M    M
 21000  -12.5   9.5   245   27   14   5.5   3.0   35.4  95.7     5.4      M    M
 20000  -11.4  11.5   245   26   13   0.3   0.2   33.7  92.6     3.6      M    M
 19500  -10.2  13.6   245   27   14  12.4   6.8   33.3  92.0     3.4      M    M
 19000   -8.8  16.2   245   26   14   9.5   5.2   33.3  92.0     3.3      M    M
 18500   -7.4  18.7   245   25   13   9.4   5.2   33.3  91.9     3.2      M    M
 18000   -6.1  21.0   250   24   12   9.5   5.2   33.2  91.8     3.2      M    M
 17500   -4.7  23.5   250   23   12   9.1   5.0   33.2  91.7     3.1      M    M
 17000   -3.3  26.1   250   22   11   8.5   4.7   33.1  91.5     3.0      M    M
 16500   -2.1  28.2   255   21   11   6.0   3.3   32.6  90.7     2.8      M    M
 16000   -0.8  30.6   255   20   10  10.4   5.7   32.4  90.3     2.7      M    M
 15500    0.6  33.1   250   19   10  10.5   5.8   32.4  90.4     2.7      M    M
 15000    2.5  36.5   235   17    9   9.3   5.1   32.2  90.0     2.4      M    M
 14500    3.9  39.0   225   17    9   9.4   5.2   32.2  90.0     2.3      M    M
 14000    4.5  40.1   220   16    8   1.9   1.1   31.5  88.6     1.5      M    M
 13500    4.8  40.6   225   14    7   2.7   1.5   30.3  86.5     0.3      M    M
 13000    5.2  41.4   225   11    6   2.8   1.6   29.2  84.5    -0.8    602  3.1
 12500    5.6  42.1   235    8    4   3.0   1.6   28.0  82.5    -1.8    574  2.9
 12000    6.0  42.8   240    6    3   5.4   3.0   27.0  80.5    -2.8    547  2.8
 11500    7.2  45.0   230    8    4   7.6   4.2   26.6  79.9    -3.2    497  2.5
 11000    8.4  47.1   220   10    5   7.8   4.3   26.3  79.4    -3.5    447  2.3
 10500    9.6  49.3   215   12    6   9.4   5.1   26.1  78.9    -3.7    396  2.0
 10250   10.3  50.5   205   12    6  10.2   5.6   26.1  79.0    -3.7    366  1.9
 10000   11.1  52.0   200   12    6  10.8   5.9   26.1  79.0    -3.7    336  1.7
  9750   11.8  53.2   195   12    6   7.6   4.2   26.2  79.1    -3.7    306  1.6
  9500   12.2  54.0   190   13    7   3.1   1.7   25.8  78.4    -4.1    289  1.5
  9250   12.4  54.3   185   13    7   3.0   1.7   25.2  77.4    -4.6    275  1.4
  9000   12.6  54.7   180   14    7   3.2   1.8   24.7  76.5    -5.1    261  1.3
  8750   12.8  55.0   180   18    9   2.6   1.4   24.2  75.6    -5.7    248  1.3
  8500   13.0  55.4   185   22   11   4.8   2.7   23.7  74.6    -6.2    234  1.2
  8250   13.5  56.3   185   25   13   7.3   4.0   23.5  74.2    -6.4    212  1.1
  8000   14.0  57.2   185   29   15   6.9   3.8   23.3  73.9    -6.6    188  1.0
  7750   14.6  58.3   185   30   15   7.0   3.9   23.0  73.5    -6.8    165  0.8
  7500   15.1  59.2   180   30   16   7.0   3.8   22.8  73.1    -7.1    141  0.7
  7250   15.6  60.1   180   31   16   7.0   3.8   22.6  72.7    -7.3    118  0.6
  7000   16.2  61.2   180   32   16   7.0   3.8   22.4  72.4    -7.5     94  0.5
  6750   16.7  62.1   185   29   15   7.1   3.9   22.2  72.0    -7.7     71  0.4
  6500   17.3  63.1   185   27   14   6.7   3.7   22.0  71.6    -7.9     47  0.2
  6250   17.8  64.0   190   25   13   8.1   4.4   21.8  71.2    -8.1     24  0.1
  6000   18.3  64.9   195   22   11   2.9   1.6   21.6  70.8    -8.3      0  0.0
  5750   18.1  64.6   190   17    9  -3.9  -2.1   20.7  69.3    -9.3      M    M
  5500   17.8  64.0   180   11    6  -1.2  -0.6   19.8  67.6   -10.3      1  0.0

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

           07/29/2015 at 0900 MDT          |       07/29/2015 at 1200 MDT
                                           |
K index... +20.7  LI... -0.0               | K index... +15.2  LI... -0.3
CAPE... 0.0  CIN... -0.9                   | CAPE... +3.7  CIN... -58.1
                                           |
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 -65.8 -86.4  250  36 19   0.8   0.5 | -66.0 -86.8  240  39 20   1.3   0.7
 45000 -61.2 -78.2  245  54 28   6.8   3.7 | -60.9 -77.6  245  59 31   6.9   3.8
 40000 -50.8 -59.4  245  58 30   7.6   4.2 | -50.5 -58.9  245  65 34   7.0   3.9
 38000 -46.3 -51.3  245  59 30   7.6   4.2 | -46.3 -51.3  245  63 33   7.0   3.9
 36000 -41.7 -43.1  245  60 31   7.5   4.1 | -42.1 -43.8  245  62 32   7.2   3.9
 34000 -37.3 -35.1  245  58 30   7.3   4.0 | -37.6 -35.7  245  58 30   7.5   4.1
 32000 -32.9 -27.2  250  55 28   7.3   4.0 | -33.1 -27.6  245  55 28   7.5   4.1
 30000 -28.3 -18.9  250  46 24   6.7   3.7 | -28.4 -19.1  250  47 24   6.8   3.7
 29000 -26.3 -15.3  250  42 22   6.7   3.7 | -26.4 -15.5  250  43 22   6.8   3.7
 28000 -24.3 -11.7  250  39 20   6.5   3.6 | -24.4 -11.9  255  40 21   6.3   3.4
 27000 -22.4  -8.3  250  36 18   6.6   3.6 | -22.5  -8.5  255  37 19   6.3   3.5
 26000 -20.4  -4.7  250  33 17   6.6   3.6 | -20.6  -5.1  255  34 17   6.3   3.5
 25000 -18.4  -1.1  250  30 15   6.6   3.6 | -18.7  -1.7  255  31 16   6.7   3.7
 24000 -16.5   2.3  250  27 14   6.7   3.7 | -16.6   2.1  255  28 15   7.1   3.9
 23000 -14.5   5.9  250  25 13   6.7   3.7 | -14.4   6.1  260  26 13   7.1   3.9
 22000 -12.5   9.5  250  23 12   6.1   3.4 | -12.3   9.9  265  24 12   6.3   3.5
 21000 -10.8  12.6  250  23 12   5.8   3.2 | -10.6  12.9  265  22 11   6.0   3.3
 20000  -9.1  15.6  255  23 12   6.0   3.3 |  -8.8  16.2  265  21 11   6.1   3.3
 19500  -8.2  17.2  255  23 12   6.2   3.4 |  -7.9  17.8  265  20 10   6.2   3.4
 19000  -7.3  18.9  250  24 12   7.2   3.9 |  -7.0  19.4  265  20 10   6.5   3.6
 18500  -6.3  20.7  250  24 12   7.3   4.0 |  -6.1  21.0  265  20 10   6.6   3.6
 18000  -5.3  22.5  250  24 13   7.7   4.2 |  -5.2  22.6  265  20 10   7.3   4.0
 17500  -4.2  24.4  250  23 12   7.8   4.3 |  -4.1  24.6  265  20 10   7.6   4.2
 17000  -3.1  26.4  255  22 11   7.8   4.3 |  -3.1  26.4  265  20 10   7.8   4.3
 16500  -1.9  28.6  255  20 10   7.5   4.1 |  -1.8  28.8  265  19 10   8.6   4.7
 16000  -0.3  31.5  265  16  8   7.4   4.1 |   0.1  32.2  275  17  9   7.8   4.3
 15500   0.7  33.3  265  15  8   6.9   3.8 |   1.2  34.2  285  17  9   6.2   3.4
 15000   1.7  35.1  270  14  7   7.1   3.9 |   2.1  35.8  290  17  9   6.2   3.4
 14500   2.6  36.7  270  13  7   5.2   2.9 |   3.2  37.8  295  17  9   7.8   4.3
 14000   3.3  37.9  270  12  6   5.5   3.0 |   4.2  39.6  295  15  8   7.8   4.3
 13500   4.0  39.2  265  11  6   4.3   2.4 |   5.2  41.4  300  13  7   7.1   3.9
 13000   4.5  40.1  255  10  5   4.2   2.3 |   6.2  43.2  295  12  6   7.2   3.9
 12500   5.1  41.2  240   9  5   5.0   2.7 |   7.2  45.0  290  10  5   6.3   3.4
 12000   5.8  42.4  230   8  4   5.2   2.9 |   7.9  46.2  280   9  5   6.1   3.4
 11500   6.6  43.9  210   7  4   5.5   3.0 |   8.7  47.7  265   8  4   5.3   2.9
 11000   7.4  45.3  190   8  4   5.6   3.1 |   9.4  48.9  250   7  4   5.0   2.7
 10500   8.2  46.8  180   9  5   4.4   2.4 |  10.0  50.0  230   7  4   3.1   1.7
 10250   8.5  47.3  175   9  5   4.4   2.4 |  10.2  50.4  230   7  4   4.0   2.2
 10000   8.9  48.0  175  10  5   6.2   3.4 |  10.6  51.1  220   7  4   6.9   3.8
  9750   9.5  49.1  170  11  6   6.6   3.6 |  11.0  51.8  215   8  4   6.7   3.7
  9500  10.0  50.0  170  12  6   6.5   3.6 |  11.5  52.7  210   8  4   6.3   3.4
  9250  10.5  50.9  175  13  7   6.2   3.4 |  11.9  53.4  200   8  4   5.9   3.2
  9000  10.9  51.6  175  13  7   7.5   4.1 |  12.4  54.3  195   8  4   7.2   4.0
  8750  11.5  52.7  180  14  7   7.8   4.3 |  13.0  55.4  185   8  4   7.9   4.3
  8500  12.0  53.6  180  14  7   5.8   3.2 |  13.5  56.3  175   8  4   7.3   4.0
  8250  12.4  54.3  185  15  8   5.2   2.9 |  14.0  57.2  170   8  4   6.6   3.6
  8000  12.8  55.0  185  16  8   6.1   3.3 |  14.5  58.1  160   8  4   8.9   4.9
  7750  13.2  55.8  190  17  9   4.8   2.6 |  15.3  59.5  160   8  4  11.0   6.0
  7500  13.4  56.1  185  17  9   3.2   1.8 |  16.1  61.0  160   8  4   9.8   5.4
  7250  13.7  56.7  185  16  8   2.6   1.4 |  16.8  62.2  160   8  4   9.7   5.3
  7000  13.9  57.0  185  16  8   5.8   3.2 |  17.5  63.5  160   8  4  10.1   5.6
  6750  14.5  58.1  185  15  8   9.2   5.0 |  18.3  64.9  160   8  4  10.5   5.8
  6500  15.1  59.2  180  13  7   8.5   4.6 |  19.1  66.4  160   8  4  10.5   5.7
  6250  15.7  60.3  180  11  5   8.3   4.6 |  19.9  67.8  160   8  4  10.4   5.7
  6000  16.4  61.5  180   8  4   9.6   5.3 |  20.6  69.1  160   8  4  10.7   5.9
  5750  17.2  63.0  175   7  4  14.0   7.7 |  21.6  70.9  160   7  4  17.4   9.6
  5500  18.4  65.1  175   6  3  17.2   9.4 |  23.3  73.9  155   7  4  27.7  15.2

           07/29/2015 at 1500 MDT          |       07/29/2015 at 1800 MDT
                                           |
K index... +21.0  LI... -1.6               | K index... +28.0  LI... -2.7
CAPE... +196.3  CIN... -41.8               | CAPE... +279.3  CIN... -9.6
                                           |
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 -65.7 -86.3  245  42 22   1.2   0.7 | -66.3 -87.3  250  42 22   1.2   0.7
 45000 -60.6 -77.1  245  63 32   6.8   3.7 | -61.2 -78.2  250  61 31   6.8   3.8
 40000 -50.2 -58.4  250  69 36   7.3   4.0 | -50.6 -59.1  250  63 33   8.2   4.5
 38000 -45.8 -50.4  250  66 34   7.3   4.0 | -45.7 -50.3  250  62 32   8.2   4.5
 36000 -41.4 -42.5  250  63 33   7.3   4.0 | -40.8 -41.4  255  61 31   7.9   4.3
 34000 -37.1 -34.8  250  60 31   7.3   4.0 | -36.3 -33.3  255  59 31   7.5   4.1
 32000 -32.7 -26.9  250  56 29   7.2   3.9 | -31.2 -24.2  250  58 30   7.8   4.3
 30000 -28.1 -18.6  250  50 26   6.7   3.6 | -27.2 -17.0  255  52 27   6.7   3.7
 29000 -26.1 -15.0  255  47 24   6.7   3.7 | -25.2 -13.4  260  49 25   6.7   3.7
 28000 -24.2 -11.6  255  44 23   6.1   3.4 | -23.3  -9.9  260  46 24   5.8   3.2
 27000 -22.3  -8.1  255  41 21   6.2   3.4 | -21.5  -6.7  265  43 22   5.9   3.2
 26000 -20.5  -4.9  260  37 19   6.2   3.4 | -19.7  -3.5  265  39 20   5.9   3.2
 25000 -18.6  -1.5  260  34 17   6.6   3.6 | -18.0  -0.4  270  36 19   6.2   3.4
 24000 -16.5   2.3  265  31 16   6.9   3.8 | -16.0   3.2  275  34 18   6.6   3.6
 23000 -14.5   5.9  270  28 14   7.0   3.8 | -14.0   6.8  275  32 17   6.6   3.6
 22000 -12.4   9.7  275  25 13   6.6   3.6 | -12.0  10.4  280  30 16   5.9   3.2
 21000 -10.5  13.1  275  24 12   6.4   3.5 | -10.4  13.3  285  29 15   5.4   3.0
 20000  -8.6  16.5  280  23 12   6.5   3.6 |  -8.8  16.2  290  28 14   5.5   3.0
 19500  -7.6  18.3  280  22 12   6.6   3.6 |  -8.0  17.6  290  28 14   5.6   3.1
 19000  -6.6  20.1  280  22 12   7.3   4.0 |  -7.1  19.2  290  27 14   6.8   3.7
 18500  -5.5  22.1  285  23 12   7.3   4.0 |  -6.1  21.0  295  27 14   6.9   3.8
 18000  -4.5  23.9  285  23 12   6.0   3.3 |  -5.2  22.6  295  27 14   6.6   3.6
 17500  -3.7  25.3  290  23 12   5.5   3.0 |  -4.3  24.3  300  25 13   6.6   3.6
 17000  -2.9  26.8  290  23 12   5.7   3.2 |  -3.4  25.9  300  24 12   7.0   3.8
 16500  -1.4  29.5  295  23 12   7.1   3.9 |  -1.7  28.9  305  20 10   8.6   4.7
 16000  -0.4  31.3  295  23 12   7.6   4.1 |  -0.5  31.1  310  17  9   8.3   4.6
 15500   0.6  33.1  300  21 11   8.2   4.5 |   0.6  33.1  315  15  7   7.3   4.0
 15000   1.8  35.2  305  20 10   8.4   4.6 |   1.7  35.1  320  12  6   7.3   4.0
 14500   2.9  37.2  305  17  9   8.1   4.5 |   2.7  36.9  325   9  4   7.1   3.9
 14000   4.1  39.4  315  14  7   8.2   4.5 |   3.8  38.8  335   6  3   7.1   3.9
 13500   5.2  41.4  320  12  6   7.6   4.1 |   4.8  40.6  360   3  2   7.1   3.9
 13000   6.4  43.5  330  10  5   7.6   4.1 |   5.9  42.6  050   2  1   7.1   3.9
 12500   7.5  45.5  335   8  4   7.3   4.0 |   6.9  44.4  100   3  2   7.3   4.0
 12000   8.6  47.5  340   6  3   7.3   4.0 |   7.9  46.2  135   4  2   7.5   4.1
 11500   9.6  49.3  345   4  2   6.1   3.3 |   8.9  48.0  155   6  3   8.5   4.7
 11000  10.3  50.5  000   0  0   5.7   3.1 |  10.1  50.2  155   7  3   8.9   4.9
 10500  10.9  51.6  155   4  2   2.1   1.2 |  11.2  52.2  155   7  4   3.8   2.1
 10250  11.0  51.8  155   4  2   6.2   3.4 |  11.4  52.5  155   7  4   7.5   4.1
 10000  11.8  53.2  150   6  3  12.6   6.9 |  12.4  54.3  155   7  4  14.4   7.9
  9750  12.5  54.5  150   7  4  10.8   5.9 |  13.3  55.9  155   7  4  12.2   6.7
  9500  13.2  55.8  150   8  4   8.8   4.8 |  14.2  57.6  155   7  4   9.4   5.1
  9250  13.8  56.8  150   8  4   7.8   4.3 |  14.8  58.6  155   7  4   7.9   4.3
  9000  14.5  58.1  145   8  4  11.5   6.3 |  15.4  59.7  155   7  4  11.0   6.0
  8750  15.4  59.7  150   8  4  12.3   6.8 |  16.3  61.3  155   7  4  11.6   6.4
  8500  16.2  61.2  150   8  4   9.8   5.4 |  17.1  62.8  155   7  4  10.0   5.5
  8250  16.9  62.4  150   8  4   8.9   4.9 |  17.8  64.0  155   7  4   9.6   5.3
  8000  17.6  63.7  150   8  4  10.5   5.7 |  18.6  65.5  155   7  4   9.8   5.4
  7750  18.4  65.1  145   8  4  10.9   6.0 |  19.3  66.7  155   7  4  10.0   5.5
  7500  19.2  66.6  145   8  4   9.6   5.3 |  20.1  68.2  155   7  4  10.0   5.5
  7250  19.9  67.8  145   8  4   9.4   5.1 |  20.8  69.4  155   7  4  10.2   5.6
  7000  20.6  69.1  145   8  4  10.3   5.6 |  21.5  70.7  155   7  4   9.6   5.3
  6750  21.4  70.5  145   7  4  10.6   5.8 |  22.3  72.1  150   7  4   9.9   5.4
  6500  22.2  72.0  145   7  4  10.1   5.5 |  23.0  73.4  150   7  4  10.6   5.8
  6250  22.9  73.2  145   7  4   9.9   5.4 |  23.8  74.8  150   7  4  10.3   5.7
  6000  23.7  74.7  145   7  4  11.2   6.2 |  24.6  76.3  150   7  3  10.7   5.9
  5750  24.7  76.5  145   7  4  18.4  10.1 |  25.5  77.9  150   6  3  14.0   7.7
  5500  26.4  79.5  145   7  4  25.8  14.2 |  26.6  79.9  150   6  3  18.4  10.1
________________________________________________________________________________

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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