Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 200119
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1819 MST Thursday, February 19, 2015

This forecast is for Friday, February 20, 2015:

If the trigger temperature of 52.3 F/11.3 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 400 ft/min (2.0 m/s)
   Maximum height of thermals.................. 10680 ft MSL (5373 ft AGL)

Forecast maximum temperature................... 55.0 F/13.2 C
Time of trigger temperature.................... 1215 MST
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................. 7786 ft MSL (2479 ft AGL)
Thermal soaring outlook for Saturday 02/21..... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 16116 ft MSL (10809 ft AGL)
Wave soaring outlook for Saturday 02/21........ Poor

Remarks... None

Sunrise/Sunset.................... 06:45:29 / 17:40:05 MST
Total possible sunshine........... 10 hr 54 min 35 sec (654 min 35 sec)
Altitude of sun at 12:13:04 MST... 39.44 degrees

Upper air data from numerical model forecast valid on 02/20/2015 at 0500 MST

Freezing level.................. 5349 ft MSL (42 ft AGL)
Additional freezing level....... 8966 ft MSL (3659 ft AGL)
Convective condensation level... 15123 ft MSL (9816 ft AGL)
Lifted condensation level....... 13479 ft MSL (8172 ft AGL)
Lifted index.................... +3.9
K index......................... +3.1

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  -58.3 -72.9   285   38   20   1.6   0.9      M     M       M      M    M
 45000  -55.9 -68.6   285   81   42   1.5   0.8      M     M       M      M    M
 40000  -59.6 -75.3   285   94   48  -2.9  -1.6      M     M       M      M    M
 38000  -60.2 -76.4   280   94   48   3.4   1.9      M     M       M      M    M
 36000  -58.1 -72.6   280   88   45   3.5   1.9      M     M       M      M    M
 34000  -56.0 -68.8   280   82   42   5.0   2.8      M     M       M      M    M
 32000  -51.6 -60.9   280   78   40   7.5   4.1      M     M       M      M    M
 30000  -47.1 -52.8   280   74   38   7.8   4.3   29.3  84.8    12.4      M    M
 29000  -44.1 -47.4   280   68   35   7.8   4.3   28.2  82.7    11.7      M    M
 28000  -41.8 -43.2   280   64   33   7.8   4.3   27.4  81.3    11.2      M    M
 27000  -39.5 -39.1   280   60   31   7.8   4.3   26.8  80.2    10.9      M    M
 26000  -37.2 -35.0   280   56   29   7.4   4.1   25.9  78.6    10.3      M    M
 25000  -35.0 -31.0   280   52   27   7.4   4.1   25.0  76.9     9.7      M    M
 24000  -32.8 -27.0   280   48   24   7.4   4.1   24.2  75.6     9.2      M    M
 23000  -30.4 -22.7   280   45   23   8.0   4.4   23.4  74.2     8.7      M    M
 22000  -28.1 -18.6   285   42   22   8.0   4.4   22.8  73.0     8.2      M    M
 21000  -25.7 -14.3   290   40   21   7.9   4.3   22.2  72.0     7.9      M    M
 20000  -23.4 -10.1   290   40   20   7.6   4.2   21.4  70.5     7.3      M    M
 19500  -22.2  -8.0   290   40   20   7.6   4.2   21.0  69.8     7.0      M    M
 19000  -21.1  -6.0   295   40   20   7.6   4.2   20.7  69.2     6.7      M    M
 18500  -20.0  -4.0   295   39   20   7.6   4.2   20.3  68.6     6.5      M    M
 18000  -18.9  -2.0   295   39   20   7.5   4.1   20.0  67.9     6.2      M    M
 17500  -17.7   0.1   295   38   20   7.5   4.1   19.6  67.2     5.8      M    M
 17000  -16.6   2.1   295   37   19   7.4   4.1   19.2  66.6     5.5      M    M
 16500  -15.5   4.1   300   38   20   7.4   4.0   18.8  65.8     5.2      M    M
 16000  -14.4   6.1   300   39   20   7.3   4.0   18.4  65.1     4.9      M    M
 15500  -12.9   8.8   300   39   20   7.0   3.9   17.7  63.9     4.3      M    M
 15000  -11.8  10.8   305   40   20   6.9   3.8   17.3  63.1     3.9      M    M
 14500  -10.8  12.6   305   39   20   6.9   3.8   16.8  62.2     3.5      M    M
 14000   -9.8  14.4   305   38   20   6.9   3.8   16.3  61.4     3.1      M    M
 13500   -8.8  16.2   305   37   19   6.9   3.8   15.8  60.5     2.6      M    M
 13000   -7.7  18.1   305   36   19   6.8   3.7   15.4  59.7     2.2      M    M
 12500   -6.8  19.8   305   35   18   6.3   3.5   14.8  58.7     1.7      M    M
 12000   -5.9  21.4   305   34   17   6.4   3.5   14.3  57.7     1.2      M    M
 11500   -4.8  23.4   305   32   17   7.1   3.9   13.8  56.9     0.7      M    M
 11000   -3.8  25.2   305   31   16   6.8   3.7   13.4  56.1     0.3      M    M
 10500   -3.0  26.6   305   29   15   5.3   2.9   12.8  55.0    -0.3    383  1.9
 10250   -2.6  27.3   305   28   14   5.5   3.0   12.4  54.4    -0.6    364  1.8
 10000   -2.1  28.2   305   27   14   7.9   4.3   12.2  53.9    -0.9    343  1.7
  9750   -1.5  29.3   305   26   13   8.1   4.4   12.1  53.7    -1.0    317  1.6
  9500   -1.0  30.2   305   25   13   6.3   3.5   11.8  53.3    -1.3    295  1.5
  9250   -0.5  31.1   305   24   12   7.0   3.8   11.6  52.9    -1.5    273  1.4
  9000   -0.0  32.0   305   22   12   6.2   3.4   11.4  52.5    -1.8    251  1.3
  8750    0.4  32.7   305   21   11   6.3   3.4   11.1  51.9    -2.1    231  1.2
  8500    0.9  33.6   305   20   10   7.0   3.8   10.8  51.5    -2.3    208  1.1
  8250    1.4  34.5   300   19   10   6.8   3.8   10.6  51.1    -2.5    186  0.9
  8000    1.9  35.4   300   18    9   6.9   3.8   10.4  50.7    -2.8    164  0.8
  7750    2.4  36.3   295   16    8   6.3   3.5   10.2  50.3    -3.0    142  0.7
  7500    2.8  37.0   295   15    8   5.5   3.0    9.9  49.8    -3.3    121  0.6
  7250    3.3  37.9   290   13    7   6.9   3.8    9.6  49.2    -3.6    100  0.5
  7000    3.9  39.0   285   11    6   9.0   4.9    9.4  49.0    -3.7     75  0.4
  6750    4.6  40.3   275   10    5   8.9   4.9    9.4  48.9    -3.8     47  0.2
  6500    5.2  41.4   270    9    5   8.1   4.5    9.3  48.7    -3.9     21  0.1
  6250    5.6  42.1   260    8    4   0.7   0.4    9.0  48.2    -4.2      1  0.0
  6000    5.4  41.7   250    8    4  -1.9  -1.1    8.0  46.5    -5.2      M    M
  5750    5.2  41.4   240    8    4  -8.9  -4.9    7.1  44.8    -6.1      M    M
  5500    3.3  37.9   225   11    5 -41.6 -22.8    4.6  40.3    -8.7     46  0.2

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

           02/20/2015 at 0800 MST          |       02/20/2015 at 1100 MST
                                           |
K index... +5.1  LI... +277.4              | K index... +5.5  LI... +275.3
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 -55.9 -68.6  290  52 27  -0.2  -0.1 | -56.6 -69.9  290  48 25   0.7   0.4
 45000 -56.2 -69.2  285  76 39  -0.2  -0.1 | -55.6 -68.1  285  73 38   0.6   0.4
 40000 -57.6 -71.7  285  85 44  -1.1  -0.6 | -56.3 -69.3  275  79 41  -0.6  -0.4
 38000 -58.0 -72.4  285  87 45   1.6   0.9 | -56.4 -69.5  275  81 42   2.1   1.2
 36000 -56.9 -70.4  280  91 47   1.5   0.8 | -55.1 -67.2  275  87 45   1.9   1.1
 34000 -56.0 -68.8  275  94 48   3.7   2.0 | -53.9 -65.0  275  92 47   2.2   1.2
 32000 -52.1 -61.8  275  83 43   6.6   3.6 | -51.9 -61.4  270  84 43   3.5   1.9
 30000 -48.2 -54.8  275  72 37   7.2   4.0 | -49.7 -57.5  270  76 39   5.1   2.8
 29000 -45.9 -50.6  275  68 35   7.4   4.1 | -47.5 -53.5  270  74 38   7.7   4.2
 28000 -43.7 -46.7  275  65 33   7.4   4.1 | -45.2 -49.4  270  71 37   7.7   4.2
 27000 -41.5 -42.7  275  61 31   7.4   4.0 | -42.9 -45.2  275  69 35   7.8   4.3
 26000 -39.2 -38.6  275  58 30   7.9   4.4 | -40.4 -40.7  275  66 34   8.5   4.7
 25000 -36.8 -34.2  275  55 28   7.9   4.4 | -37.8 -36.0  275  63 32   8.5   4.7
 24000 -34.4 -29.9  275  52 27   7.9   4.4 | -35.3 -31.5  275  59 30   8.5   4.7
 23000 -32.0 -25.6  275  50 26   8.3   4.5 | -32.8 -27.0  275  56 29   8.2   4.5
 22000 -29.5 -21.1  275  47 24   8.3   4.6 | -30.3 -22.5  275  54 28   8.2   4.5
 21000 -27.0 -16.6  280  44 23   8.3   4.6 | -27.8 -18.0  275  51 26   8.3   4.5
 20000 -24.6 -12.3  280  41 21   8.1   4.4 | -25.4 -13.7  275  47 24   7.9   4.4
 19500 -23.4 -10.1  280  40 21   8.1   4.4 | -24.2 -11.6  275  44 23   7.9   4.4
 19000 -22.2  -8.0  280  38 20   8.1   4.4 | -23.0  -9.4  275  41 21   7.9   4.4
 18500 -21.0  -5.8  280  37 19   8.1   4.4 | -21.9  -7.4  275  39 20   7.9   4.3
 18000 -19.2  -2.6  285  36 18   8.0   4.4 | -20.1  -4.2  275  38 19   8.1   4.4
 17500 -18.0  -0.4  285  35 18   8.0   4.4 | -18.8  -1.8  280  39 20   8.1   4.5
 17000 -16.8   1.8  285  35 18   7.5   4.1 | -17.7   0.1  280  39 20   7.6   4.2
 16500 -15.7   3.7  290  34 18   7.5   4.1 | -16.5   2.3  280  37 19   7.6   4.2
 16000 -14.5   5.9  290  35 18   7.7   4.2 | -15.4   4.3  280  36 19   7.8   4.3
 15500 -13.4   7.9  290  36 18   7.7   4.2 | -14.2   6.4  280  37 19   7.9   4.3
 15000 -12.2  10.0  290  37 19   7.4   4.1 | -13.0   8.6  280  37 19   7.9   4.3
 14500 -11.2  11.8  295  36 19   6.9   3.8 | -11.9  10.6  280  38 20   8.0   4.4
 14000 -10.2  13.6  295  35 18   6.9   3.8 | -10.7  12.7  285  39 20   8.0   4.4
 13500  -9.1  15.6  295  35 18   7.0   3.8 |  -9.5  14.9  285  40 21   7.5   4.1
 13000  -8.1  17.4  300  34 18   7.0   3.8 |  -8.4  16.9  285  41 21   7.5   4.1
 12500  -7.1  19.2  300  34 17   7.1   3.9 |  -7.3  18.9  285  41 21   7.8   4.3
 12000  -6.0  21.2  300  33 17   7.1   3.9 |  -6.2  20.8  285  42 21   7.8   4.3
 11500  -5.0  23.0  300  32 16   6.7   3.7 |  -5.1  22.8  285  41 21   7.4   4.0
 11000  -4.0  24.8  300  31 16   6.8   3.7 |  -4.0  24.8  285  39 20   7.5   4.1
 10500  -3.1  26.4  300  29 15   6.1   3.3 |  -3.0  26.6  285  36 18   6.7   3.7
 10250  -2.6  27.3  300  28 15   5.9   3.2 |  -2.5  27.5  285  34 17   6.8   3.7
 10000  -2.2  28.0  300  27 14   7.2   4.0 |  -2.0  28.4  285  31 16   8.5   4.7
  9750  -1.6  29.1  300  26 13   6.9   3.8 |  -1.3  29.7  285  29 15   8.4   4.6
  9500  -1.2  29.8  300  25 13   5.5   3.0 |  -0.8  30.6  285  26 13   6.8   3.7
  9250  -0.7  30.7  300  24 12   5.7   3.1 |  -0.2  31.6  285  23 12   7.5   4.1
  9000  -0.3  31.5  300  22 12   6.3   3.5 |   0.3  32.5  285  21 11   6.2   3.4
  8750   0.2  32.4  300  21 11   6.1   3.4 |   0.7  33.3  285  19 10   5.5   3.0
  8500   0.6  33.1  295  20 10   5.3   2.9 |   1.2  34.2  280  16  8   6.2   3.4
  8250   0.9  33.6  295  18  9   5.3   2.9 |   1.6  34.9  275  14  7   5.7   3.1
  8000   1.3  34.3  295  17  9   6.4   3.5 |   2.1  35.8  270  12  6   7.2   4.0
  7750   1.9  35.4  290  14  7   6.5   3.5 |   2.7  36.9  260   9  5   7.6   4.2
  7500   2.3  36.1  285  13  7   5.2   2.8 |   3.2  37.8  250   8  4   6.3   3.5
  7250   2.7  36.9  275  11  6   6.3   3.5 |   3.7  38.7  240   8  4   6.7   3.7
  7000   3.2  37.8  265  10  5   8.6   4.7 |   4.2  39.6  225   8  4   7.7   4.2
  6750   3.9  39.0  250   9  4   8.3   4.6 |   4.8  40.6  215   8  4   7.9   4.3
  6500   4.5  40.1  240   8  4   8.5   4.6 |   5.4  41.7  210   8  4   8.2   4.5
  6250   5.0  41.0  230   8  4   1.6   0.9 |   6.0  42.8  205   9  5   6.0   3.3
  6000   4.8  40.6  220   9  4  -1.4  -0.8 |   6.2  43.2  200   8  4   4.0   2.2
  5750   4.6  40.3  215   9  5  -9.3  -5.1 |   6.4  43.5  195   8  4   2.4   1.3
  5500   2.7  36.9  205  11  6 -40.9 -22.4 |   6.3  43.3  185   6  3   0.1   0.0

           02/20/2015 at 1400 MST          |       02/20/2015 at 1700 MST
                                           |
K index... +23.9  LI... +271.5             | K index... +5.0  LI... +271.8
CAPE... +208.6  CIN... -3.6                | CAPE... +112.0  CIN... -18.7
                                           |
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 -56.4 -69.5  285  56 29   0.1   0.1 | -56.6 -69.9  290  50 26   1.9   1.1
 45000 -56.3 -69.3  285  66 34   0.1   0.1 | -53.7 -64.7  290  55 28   1.9   1.0
 40000 -53.6 -64.5  275  67 35   2.0   1.1 | -53.2 -63.8  285  73 37   0.2   0.1
 38000 -52.5 -62.5  275  69 36   1.1   0.6 | -53.1 -63.6  285  81 42  -0.3  -0.2
 36000 -51.8 -61.2  280  80 41   1.2   0.6 | -53.3 -63.9  290  90 46  -0.3  -0.2
 34000 -51.0 -59.8  285  93 48   0.9   0.5 | -53.5 -64.3  290 101 52  -1.0  -0.5
 32000 -49.3 -56.7  280  90 46   3.2   1.7 | -50.4 -58.7  290 107 55   6.0   3.3
 30000 -47.4 -53.3  280  86 44   3.2   1.7 | -46.8 -52.2  290 113 58   6.0   3.3
 29000 -46.4 -51.5  280  80 41   3.3   1.8 | -44.9 -48.8  295 109 56   6.4   3.5
 28000 -45.4 -49.7  275  74 38   3.3   1.8 | -43.0 -45.4  295 103 53   6.4   3.5
 27000 -44.4 -47.9  275  68 35   3.4   1.9 | -41.0 -41.8  295  96 50   6.4   3.5
 26000 -43.0 -45.4  275  62 32   7.2   3.9 | -39.5 -39.1  295  88 45   2.3   1.2
 25000 -40.9 -41.6  275  56 29   6.9   3.8 | -38.7 -37.7  295  75 39   2.6   1.5
 24000 -38.8 -37.8  270  49 25   7.0   3.8 | -37.9 -36.2  300  62 32   2.6   1.4
 23000 -36.6 -33.9  270  44 23   9.3   5.1 | -36.8 -34.2  300  51 26   6.8   3.7
 22000 -33.8 -28.8  270  40 20   9.1   5.0 | -34.9 -30.8  300  46 24   6.4   3.5
 21000 -31.1 -24.0  270  36 18   9.2   5.0 | -33.0 -27.4  300  40 21   6.4   3.5
 20000 -28.6 -19.5  270  35 18   7.8   4.3 | -30.8 -23.4  300  37 19   8.0   4.4
 19500 -27.4 -17.3  275  37 19   7.8   4.3 | -29.6 -21.3  300  37 19   8.1   4.4
 19000 -26.3 -15.3  275  38 20   7.8   4.3 | -28.4 -19.1  300  36 19   8.1   4.4
 18500 -25.1 -13.2  280  40 20   7.8   4.3 | -27.2 -17.0  300  36 18   8.1   4.5
 18000 -23.9 -11.0  280  41 21   8.0   4.4 | -26.0 -14.8  300  35 18   8.7   4.8
 17500 -22.7  -8.9  280  39 20   8.0   4.4 | -23.9 -11.0  300  36 19   9.3   5.1
 17000 -21.0  -5.8  280  36 18   7.6   4.2 | -22.5  -8.5  300  37 19   8.8   4.8
 16500 -19.9  -3.8  280  35 18   7.5   4.1 | -21.2  -6.2  305  36 19   8.6   4.7
 16000 -18.8  -1.8  280  35 18   7.6   4.2 | -20.0  -4.0  305  36 19   8.5   4.7
 15500 -17.6   0.3  285  33 17   8.0   4.4 | -18.7  -1.7  310  36 19   8.3   4.6
 15000 -16.4   2.5  285  32 16   8.0   4.4 | -17.5   0.5  310  36 19   8.3   4.6
 14500 -15.3   4.5  285  31 16   7.9   4.3 | -16.3   2.7  310  36 18   7.9   4.3
 14000 -14.1   6.6  290  31 16   7.9   4.4 | -15.1   4.8  310  35 18   7.9   4.3
 13500 -12.9   8.8  290  31 16   8.1   4.4 | -13.9   7.0  315  34 17   7.8   4.3
 13000 -11.7  10.9  290  30 16   8.0   4.4 | -12.8   9.0  315  33 17   7.8   4.3
 12500 -10.5  13.1  290  30 15   8.6   4.7 | -11.6  11.1  315  32 16   7.9   4.4
 12000  -9.2  15.4  290  28 14   8.6   4.7 | -10.4  13.3  315  31 16   7.9   4.3
 11500  -8.0  17.6  290  26 13   7.9   4.3 |  -9.2  15.4  315  29 15   8.5   4.7
 11000  -6.9  19.6  295  23 12   8.0   4.4 |  -8.0  17.6  315  27 14   8.6   4.7
 10500  -5.7  21.7  300  20 10   7.4   4.1 |  -6.8  19.8  315  26 13   7.5   4.1
 10250  -5.2  22.6  305  19 10   7.3   4.0 |  -6.3  20.7  315  25 13   6.9   3.8
 10000  -4.6  23.7  305  18  9   8.7   4.8 |  -5.7  21.7  315  25 13   9.7   5.3
  9750  -3.9  25.0  310  16  8   9.3   5.1 |  -4.9  23.2  315  24 12  10.6   5.8
  9500  -3.3  26.1  315  15  8   8.3   4.6 |  -4.2  24.4  315  23 12   8.5   4.7
  9250  -2.6  27.3  320  14  7   8.8   4.9 |  -3.6  25.5  315  22 11   9.0   4.9
  9000  -2.0  28.4  325  14  7   7.8   4.3 |  -2.9  26.8  315  21 11   9.3   5.1
  8750  -1.5  29.3  325  13  7   8.0   4.4 |  -2.2  28.0  315  20 10   9.2   5.0
  8500  -0.8  30.6  330  12  6   9.4   5.2 |  -1.6  29.1  315  19 10   8.7   4.8
  8250  -0.1  31.8  335  12  6   8.5   4.7 |  -0.9  30.4  310  18  9   8.5   4.7
  8000   0.5  32.9  340  12  6  10.6   5.8 |  -0.3  31.5  310  17  9   9.6   5.3
  7750   1.4  34.5  345  11  6  10.5   5.7 |   0.5  32.9  310  16  8   9.4   5.2
  7500   2.0  35.6  345  11  6   8.4   4.6 |   1.1  34.0  310  15  8   8.0   4.4
  7250   2.6  36.7  350  11  6   9.1   5.0 |   1.7  35.1  310  14  7   8.7   4.8
  7000   3.3  37.9  350  11  6  10.2   5.6 |   2.3  36.1  310  13  7  10.3   5.7
  6750   4.1  39.4  350  11  6  10.1   5.5 |   3.1  37.6  305  12  6   9.7   5.3
  6500   4.8  40.6  350  11  6   9.0   4.9 |   3.7  38.7  305  12  6   8.2   4.5
  6250   5.5  41.9  350  11  6   9.9   5.4 |   4.4  39.9  305  11  6   9.4   5.1
  6000   6.3  43.3  350  11  6  10.8   5.9 |   5.1  41.2  305  10  5  10.2   5.6
  5750   7.1  44.8  350  11  6  10.2   5.6 |   5.8  42.4  305   9  5   9.3   5.1
  5500   7.8  46.0  350  10  5  11.5   6.3 |   6.4  43.5  305   7  4   5.6   3.1
________________________________________________________________________________

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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