Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 251225
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0625 MDT Thursday, August 25, 2016

This forecast is for Thursday, August 25, 2016:

If the trigger temperature of 71.3 F/21.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 417 ft/min (2.1 m/s)
   Maximum height of thermals.................. 10953 ft MSL (5668 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................. 8763 ft MSL (3477 ft AGL)
Thermal soaring outlook for Friday 08/26....... Good

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....................... 16581 ft MSL (11296 ft AGL)
Wave soaring outlook for Friday 08/26.......... Poor

Remarks... None

Sunrise/Sunset.................... 06:21:27 / 19:41:56 MDT
Total possible sunshine........... 13 hr 20 min 29 sec (800 min 29 sec)
Altitude of sun at 13:01:17 MDT... 60.63 degrees

Upper air data from rawinsonde observation taken on 08/25/2016 at 0600 MDT

Freezing level.................. 13853 ft MSL (8568 ft AGL)
Convective condensation level... 13879 ft MSL (8594 ft AGL)
Lifted condensation level....... 13225 ft MSL (7939 ft AGL)
Lifted index.................... -1.8
K index......................... +23.6

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  -58.2 -72.8   240   41   21   2.9   1.6   98.4 209.1    43.1      M    M
 45000  -55.5 -67.9   215   59   30  -1.1  -0.6   78.4 173.0    33.7      M    M
 40000  -56.2 -69.2   220   46   24  -3.4  -1.9   53.4 128.2    19.6      M    M
 38000  -54.5 -66.1   225   43   22   7.0   3.9   47.3 117.1    16.0      M    M
 36000  -50.3 -58.5   235   42   21   7.9   4.3   44.9 112.8    14.7      M    M
 34000  -45.6 -50.1   240   39   20   7.8   4.3   43.1 109.7    13.9      M    M
 32000  -40.8 -41.4   245   37   19   9.1   5.0   41.9 107.4    13.3      M    M
 30000  -35.4 -31.7   250   36   19   9.1   5.0   41.3 106.4    13.2      M    M
 29000  -33.5 -28.3   245   34   17   6.1   3.3   40.1 104.1    12.4      M    M
 28000  -31.4 -24.5   245   32   16   6.9   3.8   39.0 102.2    11.7      M    M
 27000  -28.9 -20.0   240   29   15   5.8   3.2   37.5  99.5    10.7      M    M
 26000  -26.9 -16.4   235   28   14   9.1   5.0   36.3  97.4     9.8      M    M
 25000  -25.0 -13.0   230   26   13   5.3   2.9   35.2  95.4     9.0      M    M
 24000  -22.6  -8.7   250   26   13   8.0   4.4   34.6  94.2     8.5      M    M
 23000  -20.2  -4.4   255   19   10   7.9   4.3   33.9  93.0     8.1      M    M
 22000  -17.9  -0.2   265   12    6   5.8   3.2   33.3  91.9     7.7      M    M
 21000  -16.0   3.2   240    6    3   5.6   3.1   32.0  89.6     6.6      M    M
 20000  -14.2   6.4   255    9    5  10.4   5.7   30.7  87.3     5.6      M    M
 19500  -12.6   9.3   275    8    4   8.7   4.8   30.9  87.5     5.8      M    M
 19000  -11.5  11.3   290    8    4   4.0   2.2   30.4  86.7     5.5      M    M
 18500  -11.5  11.3   285    9    4   4.2   2.3   28.8  83.8     4.1      M    M
 18000  -10.4  13.3   285    9    5   7.9   4.4   28.4  83.2     3.8      M    M
 17500   -9.1  15.6   280   10    5   9.3   5.1   28.2  82.8     3.6      M    M
 17000   -8.1  17.4   280   11    5   4.9   2.7   27.8  82.0     3.1      M    M
 16500   -7.4  18.7   275   11    6   7.1   3.9   27.1  80.7     2.4      M    M
 16000   -6.2  20.8   275   12    6   8.0   4.4   26.8  80.3     2.1      M    M
 15500   -4.9  23.2   275   10    5   9.3   5.1   26.6  79.9     1.9      M    M
 15000   -3.5  25.7   275    8    4   9.2   5.1   26.5  79.7     1.9      M    M
 14500   -2.2  28.0   275    6    3   9.3   5.1   26.4  79.6     1.8      M    M
 14000   -0.1  31.8   280    4    2   8.9   4.9   26.3  79.4     1.8      M    M
 13500    1.1  34.0   285    5    3   7.8   4.3   26.1  79.0     1.5      M    M
 13000    2.1  35.8   295    6    3   7.7   4.2   25.7  78.2     1.0      M    M
 12500    3.4  38.1   295    7    4   9.6   5.3   25.6  78.0     0.9      M    M
 12000    4.8  40.6   300    8    4   9.1   5.0   25.5  78.0     0.9      M    M
 11500    5.9  42.6   280    5    3   6.7   3.7   25.2  77.3     0.5      M    M
 11000    6.9  44.4   240    4    2   6.9   3.8   24.7  76.5    -0.0    415  2.1
 10500    7.9  46.2   200    5    2   7.0   3.8   24.3  75.7    -0.5    372  1.9
 10250    8.4  47.1   190    5    3   6.9   3.8   24.1  75.3    -0.7    350  1.8
 10000    8.9  48.0   185    6    3   7.4   4.1   23.8  74.9    -1.0    327  1.7
  9750    9.4  48.9   180    6    3   5.6   3.1   23.6  74.5    -1.2    305  1.5
  9500    9.6  49.3   175    7    4   3.5   1.9   23.2  73.7    -1.6    289  1.5
  9250    9.9  49.8   175    7    4   3.9   2.1   22.7  72.9    -2.1    274  1.4
  9000   10.1  50.2   170    8    4   3.8   2.1   22.3  72.1    -2.6    259  1.3
  8750   10.4  50.7   170    8    4   3.8   2.1   21.8  71.2    -3.1    244  1.2
  8500   10.7  51.3   170    7    4   3.8   2.1   21.3  70.4    -3.6    229  1.2
  8250   10.9  51.6   165    7    4   3.8   2.1   20.9  69.6    -4.0    214  1.1
  8000   11.2  52.2   165    7    4   3.8   2.1   20.4  68.8    -4.5    199  1.0
  7750   11.4  52.5   165    6    3   3.8   2.1   20.0  67.9    -5.0    184  0.9
  7500   11.7  53.1   165    6    3   3.9   2.1   19.5  67.1    -5.5    169  0.9
  7250   11.9  53.4   165    5    3   3.7   2.0   19.1  66.3    -6.0    154  0.8
  7000   12.2  54.0   165    5    3   4.3   2.4   18.6  65.5    -6.5    139  0.7
  6750   12.3  54.1   175    5    2  -2.3  -1.2   18.1  64.5    -7.1    127  0.6
  6500   11.8  53.2   180    4    2  -9.3  -5.1   16.8  62.2    -8.3    135  0.7
  6250   11.3  52.3   195    4    2  -2.9  -1.6   15.5  59.9    -9.6    143  0.7
  6000   11.5  52.7   205    4    2   3.3   1.8   14.9  58.8   -10.1    131  0.7
  5750   11.9  53.4   205    3    1   4.2   2.3   14.4  57.9   -10.5    112  0.6
  5500   12.0  53.6   205    1    1  -6.4  -3.5   13.7  56.7   -11.1    100  0.5

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

           08/25/2016 at 0900 MDT          |       08/25/2016 at 1200 MDT
                                           |
K index... +23.9  LI... -1.7               | K index... +21.6  LI... -3.3
CAPE... +100.9  CIN... -53.3               | CAPE... +318.7  CIN... -87.8
                                           |
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 -57.9 -72.2  235  33 17   1.5   0.8 | -58.3 -72.9  230  34 18   1.3   0.7
 45000 -55.9 -68.6  235  48 25   0.3   0.2 | -56.3 -69.3  230  47 24   1.1   0.6
 40000 -55.3 -67.5  225  53 27   3.4   1.9 | -54.6 -66.3  225  56 29   2.3   1.3
 38000 -52.6 -62.7  225  50 26   4.4   2.4 | -52.1 -61.8  225  55 28   4.2   2.3
 36000 -50.0 -58.0  230  47 24   4.4   2.4 | -49.2 -56.6  220  53 27   4.3   2.4
 34000 -45.8 -50.4  230  44 23   8.4   4.6 | -45.3 -49.5  225  50 26   7.6   4.2
 32000 -40.8 -41.4  230  41 21   8.4   4.6 | -40.7 -41.3  225  46 24   7.6   4.2
 30000 -35.9 -32.6  235  38 20   8.2   4.5 | -35.9 -32.6  230  42 22   8.2   4.5
 29000 -33.4 -28.1  235  38 19   8.2   4.5 | -33.4 -28.1  235  40 21   8.2   4.5
 28000 -30.4 -22.7  240  37 19   8.0   4.4 | -31.0 -23.8  235  38 20   8.2   4.5
 27000 -28.1 -18.6  240  36 19   7.4   4.0 | -28.7 -19.7  240  36 19   7.4   4.1
 26000 -26.0 -14.8  245  35 18   7.4   4.1 | -26.5 -15.7  245  35 18   7.4   4.1
 25000 -23.8 -10.8  250  34 17   7.6   4.2 | -24.3 -11.7  250  33 17   7.4   4.1
 24000 -22.0  -7.6  250  31 16   5.3   2.9 | -22.3  -8.1  255  31 16   6.0   3.3
 23000 -20.4  -4.7  250  27 14   5.3   2.9 | -20.5  -4.9  255  27 14   6.0   3.3
 22000 -18.9  -2.0  250  23 12   5.1   2.8 | -18.7  -1.7  260  24 12   5.9   3.2
 21000 -16.9   1.6  255  20 11   7.3   4.0 | -16.9   1.6  260  22 11   6.4   3.5
 20000 -14.8   5.4  260  19 10   7.3   4.0 | -15.0   5.0  260  20 10   6.4   3.5
 19500 -13.7   7.3  265  19 10   7.3   4.0 | -14.0   6.8  260  19 10   6.4   3.5
 19000 -12.6   9.3  270  18  9   7.3   4.0 | -13.0   8.6  265  18  9   7.3   4.0
 18500 -11.6  11.1  275  19 10   7.3   4.0 | -11.9  10.6  265  18  9   7.8   4.3
 18000 -10.5  13.1  280  19 10   7.4   4.0 | -10.1  13.8  275  18  9   8.3   4.5
 17500  -9.3  15.3  285  18  9   8.3   4.6 |  -8.8  16.2  275  17  9   8.6   4.7
 17000  -8.1  17.4  285  17  9   8.2   4.5 |  -7.6  18.3  280  17  9   8.7   4.8
 16500  -6.9  19.6  285  15  8   9.1   5.0 |  -6.3  20.7  280  17  9   9.4   5.2
 16000  -5.5  22.1  280  14  7   9.2   5.1 |  -4.9  23.2  280  16  8   9.5   5.2
 15500  -4.2  24.4  280  13  7   9.0   4.9 |  -3.6  25.5  280  15  8   9.1   5.0
 15000  -2.3  27.9  275  11  6   8.6   4.7 |  -2.2  28.0  275  15  7   9.1   5.0
 14500  -1.1  30.0  275  10  5   7.9   4.3 |  -0.9  30.4  275  14  7   8.7   4.8
 14000   0.0  32.0  265   9  5   7.6   4.2 |   0.3  32.5  275  13  6   8.6   4.7
 13500   1.1  34.0  260   8  4   7.3   4.0 |   1.5  34.7  270  11  6   8.2   4.5
 13000   2.1  35.8  250   8  4   6.9   3.8 |   2.6  36.7  270  10  5   7.7   4.3
 12500   3.1  37.6  240   7  4   6.8   3.7 |   3.7  38.7  260  10  5   7.4   4.1
 12000   4.0  39.2  230   6  3   6.4   3.5 |   4.7  40.5  255   8  4   6.5   3.6
 11500   4.9  40.8  215   6  3   6.2   3.4 |   5.6  42.1  240   7  4   6.4   3.5
 11000   5.7  42.3  195   7  3   5.3   2.9 |   6.5  43.7  225   7  4   5.5   3.0
 10500   6.5  43.7  185   7  4   3.7   2.0 |   7.2  45.0  205   7  4   4.3   2.4
 10250   6.7  44.1  180   8  4   2.3   1.2 |   7.5  45.5  200   7  4   3.2   1.8
 10000   7.0  44.6  180   8  4   6.3   3.5 |   7.8  46.0  190   8  4   5.9   3.2
  9750   7.6  45.7  175   8  4   8.7   4.8 |   8.3  46.9  180   8  4   7.2   3.9
  9500   8.2  46.8  170   8  4   6.7   3.7 |   8.8  47.8  175   9  5   6.2   3.4
  9250   8.6  47.5  165   8  4   4.4   2.4 |   9.2  48.6  165   9  5   4.7   2.6
  9000   9.0  48.2  165   8  4   5.8   3.2 |   9.5  49.1  160   9  5   5.8   3.2
  8750   9.5  49.1  160   9  4   8.1   4.4 |  10.0  50.0  155   9  4   6.9   3.8
  8500  10.0  50.0  160   9  5   5.9   3.2 |  10.4  50.7  145   8  4   6.8   3.7
  8250  10.3  50.5  155   8  4   4.0   2.2 |  10.9  51.6  140   8  4   6.9   3.8
  8000  10.6  51.1  155   8  4   4.6   2.5 |  11.4  52.5  130   7  4   7.4   4.1
  7750  10.9  51.6  150   8  4   4.2   2.3 |  11.9  53.4  125   6  3   8.7   4.8
  7500  11.1  52.0  150   7  4   2.9   1.6 |  12.6  54.7  120   6  3   9.7   5.3
  7250  11.2  52.2  150   6  3   2.2   1.2 |  13.3  55.9  120   6  3   9.9   5.5
  7000  11.4  52.5  145   5  3   2.4   1.3 |  14.1  57.4  115   6  3   9.9   5.4
  6750  11.5  52.7  145   4  2   2.3   1.2 |  14.8  58.6  115   5  3  10.3   5.7
  6500  11.6  52.9  135   2  1   2.2   1.2 |  15.6  60.1  115   5  3  10.6   5.8
  6250  11.7  53.1  080   1  0   1.8   1.0 |  16.4  61.5  115   5  3  10.3   5.6
  6000  11.8  53.2  355   2  1   3.3   1.8 |  17.1  62.8  110   5  2  11.2   6.1
  5750  12.3  54.1  345   3  1  12.0   6.6 |  18.1  64.6  110   4  2  17.8   9.8
  5500  13.6  56.5  345   3  1  21.9  12.0 |  19.8  67.6  110   4  2  26.1  14.3

           08/25/2016 at 1500 MDT          |       08/25/2016 at 1800 MDT
                                           |
K index... +27.7  LI... -2.7               | K index... +27.9  LI... -1.0
CAPE... +387.7  CIN... -1.1                | CAPE... +84.6  CIN... -25.2
                                           |
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 -58.3 -72.9  230  34 18   1.3   0.7 | -57.9 -72.2  235  32 16   1.9   1.0
 45000 -56.5 -69.7  230  47 24   0.8   0.4 | -56.0 -68.8  235  43 22  -1.3  -0.7
 40000 -55.3 -67.5  225  61 31   2.4   1.3 | -57.9 -72.2  225  62 32   1.2   0.7
 38000 -52.5 -62.5  230  58 30   4.6   2.5 | -54.6 -66.3  225  53 27   5.8   3.2
 36000 -49.4 -56.9  235  54 28   4.7   2.6 | -50.6 -59.1  230  43 22   5.9   3.2
 34000 -45.2 -49.4  235  50 26   8.0   4.4 | -45.7 -50.3  230  37 19   9.0   5.0
 32000 -40.4 -40.7  245  45 23   8.0   4.4 | -40.3 -40.5  235  33 17   9.1   5.0
 30000 -35.4 -31.7  250  41 21   8.5   4.6 | -35.0 -31.0  235  28 15   8.7   4.8
 29000 -32.9 -27.2  250  39 20   8.5   4.7 | -32.4 -26.3  235  26 13   8.7   4.8
 28000 -30.4 -22.7  255  37 19   8.6   4.7 | -29.9 -21.8  235  24 12   8.7   4.8
 27000 -28.2 -18.8  255  35 18   6.9   3.8 | -27.6 -17.7  240  22 11   7.4   4.1
 26000 -26.2 -15.2  260  33 17   6.9   3.8 | -25.4 -13.7  240  20 10   7.4   4.1
 25000 -24.1 -11.4  265  31 16   7.0   3.8 | -23.1  -9.6  240  17  9   7.5   4.1
 24000 -22.0  -7.6  265  29 15   7.1   3.9 | -21.0  -5.8  245  16  8   7.2   4.0
 23000 -19.9  -3.8  265  27 14   7.1   3.9 | -18.9  -2.0  245  14  7   7.2   4.0
 22000 -17.8  -0.0  270  25 13   7.2   3.9 | -16.7   1.9  250  12  6   7.3   4.0
 21000 -15.8   3.6  270  22 11   6.9   3.8 | -14.7   5.5  255  11  6   6.5   3.6
 20000 -13.7   7.3  275  19 10   6.9   3.8 | -12.8   9.0  260  10  5   6.5   3.6
 19500 -12.7   9.1  275  17  9   6.9   3.8 | -11.9  10.6  260   9  5   6.6   3.6
 19000 -11.7  10.9  280  16  8   6.9   3.8 | -10.9  12.4  260   9  5   6.6   3.6
 18500 -10.7  12.7  280  15  8   6.9   3.8 |  -9.5  14.9  265   9  4   6.6   3.6
 18000  -9.2  15.4  280  13  7   7.0   3.8 |  -8.5  16.7  270   8  4   6.3   3.5
 17500  -8.1  17.4  275  12  6   7.0   3.9 |  -7.6  18.3  275   8  4   6.1   3.3
 17000  -7.1  19.2  270  11  6   7.0   3.9 |  -6.7  19.9  280   8  4   6.1   3.3
 16500  -6.0  21.2  265  10  5   7.0   3.9 |  -5.9  21.4  280   8  4   6.1   3.4
 16000  -5.0  23.0  260   8  4   7.0   3.9 |  -5.0  23.0  285   8  4   6.1   3.4
 15500  -4.0  24.8  250   7  4   7.2   3.9 |  -4.1  24.6  285   7  4   5.8   3.2
 15000  -2.9  26.8  240   7  4   7.2   4.0 |  -3.3  26.1  285   6  3   5.7   3.1
 14500  -1.9  28.6  230   7  4   7.1   3.9 |  -2.5  27.5  285   6  3   5.6   3.1
 14000  -0.8  30.6  225   7  4   7.0   3.8 |  -1.7  28.9  280   5  3   5.5   3.0
 13500   0.2  32.4  220   7  4   7.1   3.9 |  -0.9  30.4  280   4  2   5.5   3.0
 13000   1.2  34.2  205   7  3   7.4   4.1 |  -0.1  31.8  270   3  1   5.5   3.0
 12500   2.2  36.0  185   6  3   7.8   4.3 |   0.7  33.3  255   2  1   5.9   3.2
 12000   3.4  38.1  170   6  3   8.9   4.9 |   1.7  35.1  245   1  1   7.7   4.2
 11500   4.7  40.5  160   6  3   9.0   4.9 |   2.8  37.0  000   0  0   7.7   4.2
 11000   6.1  43.0  155   6  3   9.6   5.3 |   4.0  39.2  000   0  0   8.3   4.6
 10500   7.5  45.5  150   6  3   6.4   3.5 |   5.2  41.4  015   1  0   6.5   3.5
 10250   7.8  46.0  150   6  3   6.0   3.3 |   5.6  42.1  015   1  1   3.6   2.0
 10000   8.6  47.5  150   6  3  11.8   6.5 |   5.9  42.6  010   1  1   7.7   4.2
  9750   9.4  48.9  145   6  3  12.5   6.9 |   6.6  43.9  005   2  1  10.9   6.0
  9500  10.3  50.5  145   5  3  10.7   5.9 |   7.4  45.3  005   3  1   8.4   4.6
  9250  11.0  51.8  145   5  3   7.7   4.2 |   7.8  46.0  360   3  1   5.5   3.0
  9000  11.6  52.9  145   5  3   9.8   5.4 |   8.3  46.9  355   3  1   6.5   3.6
  8750  12.5  54.5  140   5  3  12.1   6.7 |   8.8  47.8  350   3  2   8.2   4.5
  8500  13.3  55.9  140   5  3  10.6   5.8 |   9.4  48.9  345   4  2   7.3   4.0
  8250  14.0  57.2  140   5  3   9.5   5.2 |   9.9  49.8  335   4  2   6.7   3.7
  8000  14.8  58.6  140   5  2   9.7   5.3 |  10.4  50.7  330   4  2   6.9   3.8
  7750  15.5  59.9  135   5  2   9.6   5.3 |  10.9  51.6  320   4  2   6.8   3.8
  7500  16.2  61.2  135   5  2  10.1   5.6 |  11.3  52.3  315   5  2   7.2   3.9
  7250  17.0  62.6  135   4  2  10.5   5.8 |  11.9  53.4  305   5  3   7.4   4.1
  7000  17.8  64.0  135   4  2  10.2   5.6 |  12.4  54.3  300   5  3   7.2   4.0
  6750  18.5  65.3  135   4  2  10.3   5.6 |  12.9  55.2  295   6  3   7.9   4.3
  6500  19.3  66.7  130   4  2  10.8   5.9 |  13.5  56.3  290   6  3   8.6   4.7
  6250  20.1  68.2  130   4  2  11.9   6.5 |  14.1  57.4  280   7  3   8.5   4.7
  6000  21.0  69.8  130   4  2   8.8   4.8 |  14.7  58.5  280   7  4   8.5   4.7
  5750  21.7  71.1  130   4  2  14.0   7.7 |  15.4  59.7  275   7  4  12.4   6.8
  5500  23.4  74.1  125   4  2  31.2  17.1 |  16.6  61.9  270   6  3  18.8  10.3
________________________________________________________________________________

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



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