Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 220019
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1819 MDT Thursday, May 21, 2015

This forecast is for Friday, May 22, 2015:

If the trigger temperature of 56.9 F/13.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 121 ft/min (0.6 m/s)
   Maximum height of thermals.................. 12545 ft MSL (7238 ft AGL)

Forecast maximum temperature................... 66.0 F/19.3 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10568 ft MSL (5261 ft AGL)
Thermal soaring outlook for Saturday 05/23..... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 14677 ft MSL (9370 ft AGL)
Wave soaring outlook for Saturday 05/23........ Poor

Remarks... None

Sunrise/Sunset.................... 05:39:26 / 20:12:40 MDT
Total possible sunshine........... 14 hr 33 min 14 sec (873 min 14 sec)
Altitude of sun at 12:56:15 MDT... 70.65 degrees

Upper air data from numerical model forecast valid on 05/22/2015 at 0600 MDT

Freezing level.................. 10552 ft MSL (5245 ft AGL)
Convective condensation level... 8675 ft MSL (3368 ft AGL)
Lifted condensation level....... 11120 ft MSL (5814 ft AGL)
Lifted index.................... -1.1
K index......................... +24.2

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  -57.5 -71.5   250   31   16   1.0   0.5      M     M       M      M    M
 45000  -56.0 -68.8   250   34   17   0.1   0.0      M     M       M      M    M
 40000  -55.8 -68.4   240   33   17   0.1   0.1      M     M       M      M    M
 38000  -55.5 -67.9   220   28   15   0.9   0.5      M     M       M      M    M
 36000  -54.8 -66.6   175   30   15   0.9   0.5      M     M       M      M    M
 34000  -52.4 -62.3   160   35   18   9.6   5.3      M     M       M      M    M
 32000  -46.6 -51.9   165   29   15   9.6   5.3      M     M       M      M    M
 30000  -41.0 -41.8   170   24   12   9.0   5.0   34.7  94.5    11.9      M    M
 29000  -38.3 -36.9   175   23   12   9.0   5.0   34.4  93.8    11.8      M    M
 28000  -35.6 -32.1   175   21   11   9.0   5.0   34.1  93.4    11.8      M    M
 27000  -32.9 -27.2   175   20   10   8.3   4.6   33.9  93.0    11.7      M    M
 26000  -30.4 -22.7   180   20   10   8.4   4.6   33.2  91.8    11.3      M    M
 25000  -28.0 -18.4   185   20   10   8.4   4.6   32.7  90.9    11.0      M    M
 24000  -25.5 -13.9   190   20   10   7.7   4.2   32.3  90.2    10.8      M    M
 23000  -23.3  -9.9   195   17    9   7.3   4.0   31.3  88.4    10.1      M    M
 22000  -21.1  -6.0   195   14    7   7.4   4.0   30.5  86.8     9.4      M    M
 21000  -19.0  -2.2   200   12    6   7.1   3.9   29.7  85.4     8.8      M    M
 20000  -16.9   1.6   200   10    5   7.1   3.9   28.6  83.5     8.0      M    M
 19500  -15.9   3.4   205    9    5   7.1   3.9   28.2  82.7     7.6      M    M
 19000  -14.8   5.4   205    8    4   7.1   3.9   27.7  81.9     7.3      M    M
 18500  -13.8   7.2   210    7    4   6.6   3.6   27.3  81.1     6.9      M    M
 18000  -12.4   9.7   205    6    3   6.2   3.4   26.4  79.5     6.1      M    M
 17500  -11.5  11.3   205    6    3   6.3   3.4   25.8  78.4     5.6      M    M
 17000  -10.6  12.9   205    5    3   6.3   3.4   25.2  77.3     5.1      M    M
 16500   -9.7  14.5   210    5    2   6.3   3.5   24.6  76.2     4.6      M    M
 16000   -8.8  16.2   215    4    2   6.4   3.5   24.0  75.2     4.1      M    M
 15500   -7.8  18.0   225    3    2   6.5   3.6   23.4  74.2     3.6      M    M
 15000   -6.9  19.6   245    2    1   5.9   3.3   22.9  73.1     3.0      M    M
 14500   -6.1  21.0   265    2    1   6.0   3.3   22.2  72.0     2.4      M    M
 14000   -5.2  22.6   285    2    1   5.8   3.2   21.6  70.9     1.8      M    M
 13500   -4.4  24.1   295    3    1   5.8   3.2   20.9  69.7     1.2      M    M
 13000   -3.5  25.7   300    3    2   5.5   3.0   20.3  68.6     0.6      M    M
 12500   -2.8  27.0   295    4    2   5.3   2.9   19.6  67.2    -0.1    514  2.6
 12000   -2.0  28.4   295    6    3   5.1   2.8   18.9  66.0    -0.8    477  2.4
 11500   -1.3  29.7   295    7    4   4.9   2.7   18.1  64.5    -1.6    441  2.2
 11000   -0.6  30.9   295    9    4   4.8   2.6   17.3  63.2    -2.3    405  2.1
 10500    0.1  32.2   295   10    5   4.1   2.3   16.5  61.7    -3.1    369  1.9
 10250    0.4  32.7   295   11    5   7.1   3.9   16.1  61.0    -3.5    351  1.8
 10000    1.1  34.0   295   12    6   6.9   3.8   16.0  60.8    -3.6    326  1.7
  9750    1.4  34.5   295   12    6   3.7   2.0   15.6  60.0    -4.1    309  1.6
  9500    1.7  35.1   295   12    6   4.6   2.5   15.2  59.3    -4.5    292  1.5
  9250    2.0  35.6   295   13    7   4.2   2.3   14.7  58.5    -4.9    276  1.4
  9000    2.3  36.1   295   13    7   5.1   2.8   14.3  57.8    -5.4    258  1.3
  8750    2.7  36.9   295   13    7   6.1   3.4   14.0  57.2    -5.7    239  1.2
  8500    3.1  37.6   290   12    6   6.3   3.4   13.7  56.7    -6.0    218  1.1
  8250    3.6  38.5   285   12    6   6.2   3.4   13.5  56.3    -6.3    198  1.0
  8000    4.0  39.2   280   11    6   6.1   3.3   13.2  55.8    -6.6    178  0.9
  7750    4.4  39.9   275   10    5   5.8   3.2   12.9  55.2    -7.0    158  0.8
  7500    4.8  40.6   270    9    5   5.6   3.1   12.6  54.7    -7.3    138  0.7
  7250    5.2  41.4   260    8    4   5.4   3.0   12.3  54.1    -7.7    119  0.6
  7000    5.6  42.1   260    7    4   5.3   2.9   11.9  53.5    -8.0    100  0.5
  6750    6.0  42.8   255    6    3   4.6   2.5   11.6  52.8    -8.4     82  0.4
  6500    6.3  43.3   250    4    2   4.0   2.2   11.1  52.1    -8.9     66  0.3
  6250    6.6  43.9   265    3    1   4.3   2.4   10.7  51.3    -9.4     50  0.3
  6000    6.8  44.2   310    2    1   4.2   2.3   10.3  50.6    -9.8     33  0.2
  5750    7.1  44.8   350    3    2   4.6   2.5    9.9  49.8   -10.3     17  0.1
  5500    7.5  45.5   355    5    2   6.0   3.3    9.6  49.2   -10.6      M    M

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

           05/22/2015 at 0900 MDT          |       05/22/2015 at 1200 MDT
                                           |
K index... +22.6  LI... +274.9             | K index... +23.4  LI... +272.2
CAPE... +0.2  CIN... -0.4                  | CAPE... +65.6  CIN... -27.6
                                           |
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 -57.6 -71.7  250  30 15   0.4   0.2 | -57.8 -72.0  250  34 17  -0.1  -0.0
 45000 -57.0 -70.6  240  34 18   0.7   0.4 | -57.8 -72.0  240  43 22   1.3   0.7
 40000 -56.1 -69.0  245  38 20   0.6   0.3 | -55.8 -68.4  250  50 26   1.3   0.7
 38000 -55.2 -67.4  235  31 16   1.8   1.0 | -54.2 -65.6  250  47 24   3.2   1.8
 36000 -54.0 -65.2  205  21 11   1.8   1.0 | -52.3 -62.1  250  41 21   3.2   1.8
 34000 -51.6 -60.9  175  21 11   8.0   4.4 | -49.8 -57.6  245  33 17   5.9   3.2
 32000 -46.8 -52.2  170  20 10   8.1   4.4 | -46.3 -51.3  225  21 11   6.0   3.3
 30000 -41.7 -43.1  175  19 10   8.9   4.9 | -42.2 -44.0  195  16  8   8.6   4.7
 29000 -39.1 -38.4  180  18  9   8.9   4.9 | -39.0 -38.2  195  16  8   8.6   4.7
 28000 -36.4 -33.5  185  17  9   8.9   4.9 | -36.4 -33.5  190  16  8   8.7   4.7
 27000 -33.8 -28.8  190  16  8   8.5   4.6 | -33.9 -29.0  195  15  8   8.6   4.7
 26000 -31.2 -24.2  200  15  7   8.5   4.7 | -31.3 -24.3  200  15  8   8.6   4.7
 25000 -28.7 -19.7  210  13  7   8.5   4.7 | -28.7 -19.7  205  15  8   8.6   4.7
 24000 -26.2 -15.2  220  12  6   8.0   4.4 | -26.2 -15.2  210  15  8   8.0   4.4
 23000 -23.9 -11.0  220  12  6   7.7   4.2 | -23.9 -11.0  215  17  9   7.9   4.3
 22000 -21.6  -6.9  220  11  6   7.7   4.2 | -21.5  -6.7  220  18  9   7.9   4.3
 21000 -19.4  -2.9  220  10  5   7.0   3.9 | -19.3  -2.7  225  19 10   5.8   3.2
 20000 -17.3   0.9  210   9  5   7.0   3.9 | -17.6   0.3  225  22 11   6.1   3.4
 19500 -16.3   2.7  210   9  5   7.0   3.9 | -16.7   1.9  225  23 12   6.1   3.4
 19000 -15.3   4.5  205   8  4   7.0   3.9 | -15.8   3.6  225  24 12   6.2   3.4
 18500 -13.8   7.2  200   8  4   6.2   3.4 | -14.9   5.2  225  25 13   6.0   3.3
 18000 -12.9   8.8  200   8  4   6.3   3.4 | -14.0   6.8  225  24 12   5.9   3.3
 17500 -12.0  10.4  205   7  4   6.2   3.4 | -13.2   8.2  230  24 12   6.1   3.3
 17000 -11.1  12.0  205   7  3   6.2   3.4 | -12.2  10.0  230  23 12   6.7   3.7
 16500 -10.2  13.6  210   6  3   6.2   3.4 | -11.3  11.7  235  22 11   6.7   3.7
 16000  -9.3  15.3  220   5  3   5.8   3.2 | -10.3  13.5  240  21 11   6.7   3.7
 15500  -8.5  16.7  230   5  3   5.8   3.2 |  -8.8  16.2  245  21 11   6.7   3.7
 15000  -7.6  18.3  255   5  3   5.9   3.2 |  -7.8  18.0  250  21 11   7.7   4.2
 14500  -6.8  19.8  275   7  4   5.9   3.3 |  -6.6  20.1  255  22 11   7.6   4.2
 14000  -5.9  21.4  285  10  5   5.6   3.1 |  -5.5  22.1  260  23 12   8.3   4.5
 13500  -5.1  22.8  295  13  7   5.6   3.1 |  -4.2  24.4  265  24 12   8.3   4.6
 13000  -4.3  24.3  295  17  9   5.7   3.1 |  -3.0  26.6  270  25 13   7.9   4.3
 12500  -3.4  25.9  290  21 11   5.8   3.2 |  -1.9  28.6  275  25 13   7.8   4.3
 12000  -2.5  27.5  290  24 12   6.4   3.5 |  -0.8  30.6  275  25 13   6.7   3.7
 11500  -1.5  29.3  285  26 13   6.9   3.8 |   0.1  32.2  280  22 11   6.3   3.5
 11000  -0.4  31.3  280  28 14   7.4   4.1 |   1.1  34.0  280  20 10   6.4   3.5
 10500   0.8  33.4  285  28 15   6.8   3.7 |   2.0  35.6  285  18  9   6.0   3.3
 10250   1.4  34.5  285  28 15  12.4   6.8 |   2.5  36.5  285  18  9   8.7   4.8
 10000   2.5  36.5  285  28 14  12.3   6.7 |   3.2  37.8  290  17  9   7.9   4.3
  9750   3.1  37.6  285  27 14   6.7   3.7 |   3.6  38.5  290  16  8   4.5   2.5
  9500   3.7  38.7  290  26 13   8.2   4.5 |   3.9  39.0  290  15  8   5.8   3.2
  9250   4.3  39.7  290  25 13   7.8   4.3 |   4.3  39.7  295  14  7   4.1   2.2
  9000   4.8  40.6  290  24 12   6.1   3.3 |   4.5  40.1  295  12  6   1.8   1.0
  8750   5.1  41.2  295  22 11   4.0   2.2 |   4.6  40.3  295  10  5   2.1   1.1
  8500   5.4  41.7  300  21 11   4.5   2.5 |   4.7  40.5  300   7  4   1.6   0.9
  8250   5.6  42.1  300  19 10   2.7   1.5 |   4.8  40.6  310   5  3   4.3   2.4
  8000   5.7  42.3  305  17  9  -0.1  -0.1 |   5.2  41.4  330   4  2   8.2   4.5
  7750   5.6  42.1  315  15  8  -0.1  -0.1 |   5.8  42.4  345   3  2   8.6   4.7
  7500   5.6  42.1  320  14  7   0.1   0.0 |   6.4  43.5  355   3  2   9.0   4.9
  7250   5.5  41.9  325  13  6   1.0   0.5 |   7.1  44.8  360   3  2  10.0   5.5
  7000   5.6  42.1  330  11  6   2.1   1.2 |   7.8  46.0  005   3  2  10.9   6.0
  6750   5.7  42.3  330   9  5   1.0   0.5 |   8.6  47.5  005   3  2   9.5   5.2
  6500   5.8  42.4  335   8  4   4.4   2.4 |   9.3  48.7  005   3  2   9.8   5.4
  6250   6.3  43.3  340   6  3   9.9   5.4 |  10.1  50.2  005   3  2  11.4   6.2
  6000   7.1  44.8  350   5  3  10.6   5.8 |  10.9  51.6  005   3  2  11.1   6.1
  5750   7.8  46.0  360   4  2  10.3   5.7 |  11.8  53.2  005   3  2  11.9   6.5
  5500   8.6  47.5  360   4  2  13.4   7.3 |  12.9  55.2  005   3  2  20.1  11.0

           05/22/2015 at 1500 MDT          |       05/22/2015 at 1800 MDT
                                           |
K index... +26.3  LI... +269.9             | K index... +24.8  LI... +271.0
CAPE... +446.4  CIN... M                   | CAPE... +304.5  CIN... -1.2
                                           |
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 -58.1 -72.6  250  38 20   0.0   0.0 | -58.6 -73.5  240  31 16  -0.1  -0.1
 45000 -57.9 -72.2  245  55 28   1.0   0.6 | -58.6 -73.5  240  57 29   1.1   0.6
 40000 -56.5 -69.7  250  67 34   1.0   0.5 | -56.9 -70.4  245  71 36   1.2   0.7
 38000 -54.5 -66.1  250  71 36   4.3   2.4 | -54.6 -66.3  250  77 40   4.9   2.7
 36000 -51.9 -61.4  255  75 38   4.3   2.4 | -51.6 -60.9  250  84 43   4.9   2.7
 34000 -48.8 -55.8  255  73 37   6.9   3.8 | -48.3 -54.9  250  87 45   6.6   3.6
 32000 -44.6 -48.3  255  57 30   6.9   3.8 | -44.4 -47.9  250  83 43   6.6   3.6
 30000 -39.8 -39.6  250  41 21   7.6   4.1 | -39.6 -39.3  250  74 38   7.6   4.2
 29000 -37.5 -35.5  250  34 17   7.6   4.1 | -37.3 -35.1  255  66 34   7.6   4.2
 28000 -35.3 -31.5  245  27 14   7.6   4.1 | -35.1 -31.2  255  58 30   7.7   4.2
 27000 -33.0 -27.4  235  21 11   7.3   4.0 | -32.7 -26.9  255  51 26   8.0   4.4
 26000 -30.9 -23.6  235  20 10   7.3   4.0 | -30.4 -22.7  255  43 22   8.0   4.4
 25000 -28.7 -19.7  235  18  9   7.3   4.0 | -28.0 -18.4  250  36 19   8.0   4.4
 24000 -26.5 -15.7  235  17  9   7.4   4.1 | -25.7 -14.3  245  31 16   7.3   4.0
 23000 -24.3 -11.7  240  18  9   7.5   4.1 | -23.5 -10.3  240  33 17   7.2   4.0
 22000 -22.0  -7.6  240  19 10   7.5   4.1 | -21.4  -6.5  240  34 18   7.2   4.0
 21000 -19.9  -3.8  245  21 11   6.3   3.5 | -19.2  -2.6  240  36 18   6.9   3.8
 20000 -18.0  -0.4  245  26 14   6.5   3.5 | -17.2   1.0  240  35 18   7.0   3.8
 19500 -17.1   1.2  245  29 15   6.5   3.6 | -16.2   2.8  240  34 18   7.0   3.8
 19000 -16.1   3.0  245  32 16   6.5   3.5 | -15.1   4.8  240  34 17   7.0   3.8
 18500 -15.1   4.8  245  33 17   7.3   4.0 | -14.1   6.6  240  34 17   7.2   3.9
 18000 -14.0   6.8  245  32 17   7.5   4.1 | -13.0   8.6  240  33 17   7.2   4.0
 17500 -12.9   8.8  245  31 16   7.5   4.1 | -12.0  10.4  240  33 17   7.3   4.0
 17000 -11.8  10.8  245  31 16   7.4   4.1 | -10.9  12.4  235  33 17   7.6   4.2
 16500 -10.8  12.6  240  30 16   7.4   4.1 |  -9.8  14.4  235  32 17   7.6   4.2
 16000  -9.7  14.5  240  30 15   7.6   4.1 |  -8.2  17.2  230  31 16   7.2   4.0
 15500  -8.1  17.4  235  29 15   7.6   4.2 |  -7.1  19.2  225  30 16   7.3   4.0
 15000  -6.9  19.6  235  28 14   7.8   4.3 |  -6.1  21.0  220  29 15   7.3   4.0
 14500  -5.8  21.6  230  27 14   7.8   4.3 |  -5.0  23.0  215  27 14   7.4   4.1
 14000  -4.7  23.5  230  26 13   7.7   4.2 |  -4.0  24.8  210  26 13   6.6   3.6
 13500  -3.6  25.5  225  24 13   7.7   4.2 |  -3.0  26.6  205  25 13   6.7   3.7
 13000  -2.5  27.5  220  23 12   7.1   3.9 |  -2.1  28.2  200  24 12   6.3   3.4
 12500  -1.5  29.3  210  22 11   7.0   3.8 |  -1.2  29.8  190  22 11   6.2   3.4
 12000  -0.6  30.9  205  20 11   6.8   3.7 |  -0.3  31.5  185  21 11   6.4   3.5
 11500   0.4  32.7  200  19 10   6.7   3.7 |   0.6  33.1  175  18  9   6.6   3.6
 11000   1.3  34.3  190  17  9   5.5   3.0 |   1.5  34.7  165  15  8   5.3   2.9
 10500   2.0  35.6  185  14  7   4.5   2.5 |   2.2  36.0  155  12  6   4.1   2.2
 10250   2.4  36.3  180  12  6   6.7   3.7 |   2.5  36.5  145  11  5   8.0   4.4
 10000   2.9  37.2  170  10  5   8.0   4.4 |   3.2  37.8  125   9  5   9.4   5.2
  9750   3.4  38.1  160   7  4   6.5   3.6 |   3.7  38.7  115   8  4   6.6   3.6
  9500   3.9  39.0  145   5  3   7.1   3.9 |   4.2  39.6  100   8  4   7.3   4.0
  9250   4.3  39.7  115   4  2   6.2   3.4 |   4.7  40.5  080   8  4   7.2   4.0
  9000   4.8  40.6  095   4  2   8.5   4.7 |   5.3  41.5  075   8  4   9.1   5.0
  8750   5.6  42.1  090   4  2  11.1   6.1 |   6.0  42.8  070   8  4  10.3   5.7
  8500   6.3  43.3  085   5  2  10.4   5.7 |   6.8  44.2  065   8  4   9.9   5.4
  8250   7.1  44.8  075   5  2  10.6   5.8 |   7.5  45.5  065   8  4  10.5   5.8
  8000   7.9  46.2  075   5  2  10.2   5.6 |   8.3  46.9  060   8  4  10.7   5.9
  7750   8.6  47.5  070   5  3   9.5   5.2 |   9.0  48.2  055   9  4   9.8   5.4
  7500   9.3  48.7  070   5  3   9.3   5.1 |   9.8  49.6  055   9  4   9.6   5.2
  7250  10.0  50.0  070   5  3  10.1   5.5 |  10.5  50.9  050   9  5   9.8   5.4
  7000  10.8  51.4  065   5  3  10.6   5.8 |  11.2  52.2  050   9  5  10.0   5.5
  6750  11.5  52.7  065   5  3   9.7   5.3 |  11.9  53.4  045   9  5   9.6   5.3
  6500  12.3  54.1  060   5  3  10.0   5.5 |  12.6  54.7  045   9  5   9.8   5.4
  6250  13.1  55.6  060   5  3  11.3   6.2 |  13.4  56.1  045   9  5  10.6   5.8
  6000  13.9  57.0  060   5  3  11.2   6.1 |  14.2  57.6  040   9  5  10.8   5.9
  5750  14.7  58.5  055   5  3  11.7   6.4 |  15.0  59.0  040   9  5  10.1   5.6
  5500  15.8  60.4  055   5  3  18.7  10.2 |  15.7  60.3  040   9  5  11.3   6.2
________________________________________________________________________________

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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