Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 191330
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0730 MDT Friday, May 19, 2017

This forecast is for Friday, May 19, 2017:

If the trigger temperature of 44.5 F/6.9 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 40 ft/min (0.2 m/s)
   Maximum height of thermals.................. 8626 ft MSL (3341 ft AGL)

Forecast maximum temperature................... 42.0 F/6.0 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
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................. 6994 ft MSL (1708 ft AGL)
Thermal soaring outlook for Saturday 05/20..... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 12913 ft MSL (7628 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 18326 ft MSL (13041 ft AGL)
Wave soaring outlook for Saturday 05/20........ Poor

Remarks...

Sunrise/Sunset.................... 05:41:19 / 20:10:28 MDT
Total possible sunshine........... 14 hr 29 min 10 sec (869 min 10 sec)
Altitude of sun at 12:56:05 MDT... 70.14 degrees

Upper air data from rawinsonde observation taken on 05/19/2017 at 0600 MDT

Freezing level.................. 5829 ft MSL (544 ft AGL)
Convective condensation level... 9673 ft MSL (4388 ft AGL)
Lifted condensation level....... 8833 ft MSL (3547 ft AGL)
Lifted index.................... +4.0
K index......................... +22.1

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  -54.8 -66.6   245    3    2   3.3   1.8  109.0 228.2    59.1      M    M
 45000  -49.6 -57.3   240   12    6   3.2   1.8   91.7 197.0    52.8      M    M
 40000  -49.6 -57.3   205   27   14   3.5   1.9   68.6 155.5    41.2      M    M
 38000  -48.1 -54.6   200   32   16   0.7   0.4   61.9 143.4    37.8      M    M
 36000  -47.7 -53.9   200   33   17   0.7   0.4   53.9 129.0    33.3      M    M
 34000  -47.3 -53.1   200   32   17   0.9   0.5   46.4 115.5    28.9      M    M
 32000  -45.8 -50.4   195   43   22   1.9   1.0   40.4 104.7    25.3      M    M
 30000  -46.2 -51.2   195   56   29  -2.2  -1.2   30.9  87.6    18.9      M    M
 29000  -46.0 -50.8   195   58   30   5.0   2.7   27.3  81.1    16.4      M    M
 28000  -44.4 -47.9   200   60   31   5.1   2.8   25.5  77.9    15.3      M    M
 27000  -42.5 -44.5   200   62   32   6.8   3.7   24.1  75.5    14.4      M    M
 26000  -40.5 -40.9   205   64   33   6.3   3.5   23.0  73.4    13.7      M    M
 25000  -38.6 -37.5   205   66   34   6.3   3.5   21.7  71.1    12.9      M    M
 24000  -36.7 -34.1   210   61   31   6.3   3.5   20.4  68.7    12.0      M    M
 23000  -34.6 -30.3   210   55   28   7.6   4.2   19.4  66.8    11.2      M    M
 22000  -32.3 -26.1   205   48   24   7.6   4.2   18.5  65.3    10.7      M    M
 21000  -30.0 -22.0   205   40   21   7.9   4.3   17.8  64.1    10.2      M    M
 20000  -28.4 -19.1   200   33   17   5.0   2.8   16.4  61.5     9.1      M    M
 19500  -27.6 -17.7   195   30   15   5.0   2.7   15.5  59.9     8.4      M    M
 19000  -26.8 -16.2   195   26   14   4.3   2.4   14.7  58.5     7.8      M    M
 18500  -24.4 -11.9   190   23   12  24.2  13.3   15.9  60.6     8.8      M    M
 18000  -22.7  -8.9   180   22   11   6.5   3.6   16.3  61.3     9.1      M    M
 17500  -21.6  -6.9   175   21   11   7.3   4.0   15.8  60.5     8.8      M    M
 17000  -20.5  -4.9   170   20   11   7.3   4.0   15.4  59.8     8.5      M    M
 16500  -19.4  -2.9   165   20   10   7.4   4.0   15.1  59.1     8.2      M    M
 16000  -18.3  -0.9   160   20   10   7.4   4.0   14.7  58.5     7.9      M    M
 15500  -17.2   1.0   160   19   10   7.4   4.0   14.3  57.7     7.6      M    M
 15000  -15.6   3.9   165   17    9   7.4   4.0   13.7  56.6     7.0      M    M
 14500  -14.5   5.9   165   15    8   7.4   4.0   13.3  55.9     6.7      M    M
 14000  -13.4   7.9   170   14    7   7.2   4.0   12.9  55.2     6.4      M    M
 13500  -12.0  10.4   160   13    7  16.4   9.0   12.8  55.1     6.3      M    M
 13000   -9.9  14.2   155   13    7  -2.0  -1.1   13.6  56.5     7.0      M    M
 12500   -9.2  15.4   145   13    7  19.0  10.4   12.8  55.0     6.3      M    M
 12000   -7.7  18.1   140   13    6   4.0   2.2   12.9  55.3     6.4      M    M
 11500   -7.2  19.0   140    9    5   3.5   1.9   11.9  53.4     5.4      M    M
 11000   -6.7  19.9   145    6    3   3.5   1.9   10.9  51.6     4.5      M    M
 10500   -6.2  20.8   150    2    1   3.5   1.9    9.9  49.8     3.6      M    M
 10250   -5.9  21.4   170    1    0   3.5   1.9    9.4  49.0     3.1      M    M
 10000   -5.7  21.7   290    1    1   3.3   1.8    8.9  48.1     2.7      M    M
  9750   -5.5  22.1   295    3    1   3.1   1.7    8.4  47.2     2.2      M    M
  9500   -5.2  22.6   295    4    2   3.2   1.7    7.9  46.2     1.7      M    M
  9250   -5.0  23.0   295    6    3   3.2   1.7    7.4  45.3     1.2      M    M
  9000   -4.8  23.4   295    7    4   3.2   1.7    6.9  44.4     0.7      M    M
  8750   -4.5  23.9   305    7    4   3.2   1.7    6.4  43.5     0.2      M    M
  8500   -4.3  24.3   315    7    4   3.2   1.7    5.9  42.6    -0.3    232  1.2
  8250   -4.1  24.6   325    8    4   3.2   1.8    5.4  41.6    -0.8    217  1.1
  8000   -3.8  25.2   330    8    4   3.1   1.7    4.9  40.8    -1.3    203  1.0
  7750   -3.6  25.5   335    9    5   3.3   1.8    4.3  39.8    -1.8    188  1.0
  7500   -3.4  25.9   335   11    6   2.7   1.5    3.8  38.9    -2.3    174  0.9
  7250   -3.1  26.4   340   12    6   5.1   2.8    3.3  38.0    -2.8    160  0.8
  7000   -2.6  27.3   340   14    7   7.9   4.3    3.2  37.7    -3.0    137  0.7
  6750   -2.1  28.2   340   15    8   7.4   4.1    3.0  37.4    -3.2    113  0.6
  6500   -1.5  29.3   340   16    8   7.5   4.1    2.8  37.0    -3.4     89  0.5
  6250   -1.0  30.2   340   17    9   7.5   4.1    2.6  36.8    -3.6     66  0.3
  6000   -0.4  31.3   340   18    9   7.5   4.1    2.5  36.5    -3.8     42  0.2
  5750    0.1  32.2   335   15    8   7.5   4.1    2.3  36.2    -4.0     18  0.1
  5500    0.7  33.3   330   11    6   7.5   4.1    2.1  35.9    -4.2      M    M

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

           05/19/2017 at 0900 MDT          |       05/19/2017 at 1200 MDT
                                           |
K index... +18.0  LI... +1.1               | K index... +17.7  LI... +2.4
CAPE... +3.3  CIN... -31.0                 | CAPE... 0.0  CIN... 0.0
                                           |
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 -54.5 -66.1  220  10  5   3.0   1.6 | -54.1 -65.4  225   9  4   2.1   1.2
 45000 -49.9 -57.8  210  15  8   2.1   1.1 | -50.9 -59.6  205  15  8   2.0   1.1
 40000 -47.2 -53.0  220  18  9   1.8   1.0 | -48.0 -54.4  210  15  8   2.0   1.1
 38000 -46.7 -52.1  215  22 11  -0.6  -0.3 | -47.2 -53.0  205  17  9   0.4   0.2
 36000 -47.1 -52.8  205  30 15  -0.6  -0.3 | -46.9 -52.4  195  24 12   0.4   0.2
 34000 -47.4 -53.3  200  38 20  -0.7  -0.4 | -46.7 -52.1  185  33 17  -1.4  -0.8
 32000 -48.2 -54.8  180  50 26  -1.3  -0.7 | -47.9 -54.2  165  39 20  -1.9  -1.1
 30000 -48.7 -55.7  170  63 33   6.5   3.6 | -48.7 -55.7  155  48 25   6.0   3.3
 29000 -46.1 -51.0  165  61 31   8.4   4.6 | -46.4 -51.5  155  48 25   7.6   4.2
 28000 -43.6 -46.5  160  59 31   8.5   4.6 | -44.1 -47.4  150  48 25   7.6   4.2
 27000 -41.1 -42.0  150  58 30   8.5   4.6 | -41.9 -43.4  145  48 25   7.4   4.0
 26000 -38.5 -37.3  155  57 29   8.4   4.6 | -39.2 -38.6  145  46 24   9.7   5.3
 25000 -36.0 -32.8  160  54 28   8.4   4.6 | -36.3 -33.3  140  43 22   9.7   5.3
 24000 -33.5 -28.3  165  53 27   8.5   4.7 | -33.4 -28.1  140  40 21   9.8   5.4
 23000 -31.3 -24.3  170  50 26   6.6   3.6 | -31.0 -23.8  140  37 19   7.1   3.9
 22000 -29.4 -20.9  175  48 25   6.5   3.6 | -28.9 -20.0  140  34 17   7.0   3.9
 21000 -27.4 -17.3  185  47 24   6.5   3.6 | -26.8 -16.2  145  31 16   7.0   3.8
 20000 -25.7 -14.3  190  40 21   5.7   3.1 | -24.9 -12.8  155  27 14   6.4   3.5
 19500 -24.8 -12.6  190  37 19   5.7   3.1 | -23.9 -11.0  160  25 13   6.4   3.5
 19000 -24.0 -11.2  190  33 17   5.7   3.1 | -23.0  -9.4  165  24 12   6.4   3.5
 18500 -23.1  -9.6  195  29 15   5.8   3.2 | -22.0  -7.6  170  23 12   6.5   3.5
 18000 -22.4  -8.3  195  26 13   4.3   2.4 | -21.1  -6.0  175  21 11   5.5   3.0
 17500 -21.7  -7.1  190  22 12   4.5   2.5 | -19.9  -3.8  185  18  9   5.7   3.1
 17000 -20.3  -4.5  185  20 10   9.1   5.0 | -18.9  -2.0  190  16  8   6.7   3.7
 16500 -19.0  -2.2  180  20 11   8.8   4.8 | -18.0  -0.4  200  13  7   6.6   3.6
 16000 -17.7   0.1  180  21 11   8.8   4.8 | -16.9   1.6  205  12  6   7.4   4.1
 15500 -16.4   2.5  185  20 10   8.8   4.8 | -15.8   3.6  210  12  6   7.5   4.1
 15000 -15.2   4.6  185  19 10   8.5   4.7 | -14.7   5.5  215  11  6   7.1   3.9
 14500 -13.9   7.0  190  19 10   8.4   4.6 | -13.7   7.3  225  10  5   6.9   3.8
 14000 -12.7   9.1  190  18  9   8.4   4.6 | -12.7   9.1  240  10  5   7.1   3.9
 13500 -11.5  11.3  190  17  9   8.5   4.6 | -11.6  11.1  250   9  5   7.3   4.0
 13000 -10.2  13.6  195  16  8   8.2   4.5 | -10.6  12.9  260   8  4   7.3   4.0
 12500  -9.1  15.6  200  14  7   7.4   4.0 |  -9.5  14.9  265   8  4   7.4   4.1
 12000  -8.0  17.6  205  12  6   6.5   3.6 |  -8.4  16.9  275   7  4   6.9   3.8
 11500  -7.3  18.9  210   9  4   4.2   2.3 |  -7.5  18.5  285   7  4   5.7   3.1
 11000  -6.7  19.9  225   5  2   4.9   2.7 |  -6.7  19.9  295   7  3   5.5   3.0
 10500  -5.8  21.6  195   3  1   6.2   3.4 |  -5.9  21.4  315   6  3   5.1   2.8
 10250  -5.4  22.3  170   3  1   6.8   3.8 |  -5.6  21.9  330   6  3   5.4   3.0
 10000  -4.9  23.2  150   3  2   4.3   2.4 |  -5.2  22.6  340   6  3   3.5   1.9
  9750  -4.7  23.5  150   3  1   4.1   2.2 |  -5.0  23.0  345   7  3   3.9   2.2
  9500  -4.3  24.3  155   2  1   6.4   3.5 |  -4.6  23.7  350   7  4   6.1   3.4
  9250  -3.8  25.2  175   1  1   5.7   3.1 |  -4.2  24.4  355   8  4   5.3   2.9
  9000  -3.5  25.7  245   1  0   4.0   2.2 |  -3.9  25.0  360  10  5   3.6   2.0
  8750  -3.2  26.2  305   2  1   2.9   1.6 |  -3.6  25.5  360  11  6   2.8   1.5
  8500  -3.0  26.6  315   4  2   3.6   2.0 |  -3.4  25.9  005  13  7   3.0   1.6
  8250  -2.7  27.1  320   6  3   3.0   1.7 |  -3.2  26.2  005  15  8   3.8   2.1
  8000  -2.5  27.5  325   8  4   3.0   1.6 |  -2.9  26.8  005  16  8   5.1   2.8
  7750  -2.3  27.9  330   9  5   1.2   0.6 |  -2.5  27.5  010  17  9   5.4   3.0
  7500  -2.3  27.9  330  11  5  -0.5  -0.3 |  -2.1  28.2  010  17  9   5.8   3.2
  7250  -2.3  27.9  335  12  6   2.3   1.2 |  -1.7  28.9  015  17  9   6.5   3.6
  7000  -2.1  28.2  340  12  6   3.5   1.9 |  -1.2  29.8  015  16  8   7.0   3.8
  6750  -1.8  28.8  345  13  7   4.1   2.3 |  -0.7  30.7  015  15  8   6.8   3.7
  6500  -1.4  29.5  350  12  6   8.0   4.4 |  -0.2  31.6  010  13  7   8.7   4.8
  6250  -0.7  30.7  350  11  6  10.4   5.7 |   0.6  33.1  010  12  6  10.3   5.7
  6000   0.0  32.0  350  10  5  10.0   5.5 |   1.3  34.3  010  11  5   9.8   5.4
  5750   0.8  33.4  350   9  5  11.0   6.0 |   2.0  35.6  005   9  5  10.8   5.9
  5500   1.7  35.1  350   9  4  15.0   8.2 |   2.9  37.2  005   9  4  14.3   7.8

           05/19/2017 at 1500 MDT          |       05/19/2017 at 1800 MDT
                                           |
K index... +17.3  LI... +2.2               | K index... +18.1  LI... +3.4
CAPE... +75.2  CIN... 0.0                  | CAPE... +26.9  CIN... 0.0
                                           |
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 -54.0 -65.2  215   9  5   2.6   1.4 | -54.5 -66.1  235  10  5   2.5   1.4
 45000 -50.1 -58.2  220  16  8   1.7   0.9 | -50.7 -59.3  220  13  7   2.2   1.2
 40000 -48.1 -54.6  205  15  8   1.3   0.7 | -47.7 -53.9  195  15  8   2.0   1.1
 38000 -47.5 -53.5  200  16  8   0.6   0.3 | -46.9 -52.4  190  15  8   0.5   0.3
 36000 -47.1 -52.8  195  20 10   0.6   0.3 | -46.7 -52.1  190  15  8   0.5   0.3
 34000 -46.8 -52.2  185  24 12  -1.4  -0.8 | -46.4 -51.5  190  15  8  -1.1  -0.6
 32000 -48.0 -54.4  170  37 19  -2.0  -1.1 | -47.7 -53.9  165  21 11  -2.1  -1.2
 30000 -48.7 -55.7  165  50 26   7.2   3.9 | -48.8 -55.8  155  29 15   4.1   2.2
 29000 -46.2 -51.2  160  46 24   8.5   4.6 | -46.5 -51.7  155  24 12   7.7   4.2
 28000 -43.6 -46.5  160  42 22   8.5   4.7 | -43.6 -46.5  155  17  9   7.7   4.2
 27000 -41.1 -42.0  155  38 20   8.6   4.7 | -41.3 -42.3  160  12  6   7.8   4.3
 26000 -38.7 -37.7  155  34 18   7.6   4.2 | -38.8 -37.8  145  11  5   8.7   4.8
 25000 -36.4 -33.5  155  30 15   7.6   4.2 | -36.2 -33.2  130  11  6   8.7   4.8
 24000 -34.1 -29.4  155  25 13   7.6   4.2 | -33.6 -28.5  110  12  6   8.7   4.8
 23000 -31.6 -24.9  150  21 11   8.7   4.8 | -30.9 -23.6  100  15  8   9.3   5.1
 22000 -29.0 -20.2  135  19 10   8.8   4.8 | -28.1 -18.6  095  18  9   9.3   5.1
 21000 -26.4 -15.5  115  18  9   8.6   4.7 | -25.4 -13.7  095  22 11   8.2   4.5
 20000 -24.1 -11.4  105  17  9   7.5   4.1 | -23.3  -9.9  085  20 10   6.8   3.7
 19500 -23.0  -9.4  100  17  9   7.5   4.1 | -22.3  -8.1  080  20 10   6.8   3.7
 19000 -21.9  -7.4  095  17  9   7.5   4.1 | -21.3  -6.3  070  19 10   6.8   3.7
 18500 -20.2  -4.4  085  18  9   6.8   3.7 | -20.3  -4.5  065  19 10   6.7   3.7
 18000 -19.3  -2.7  085  15  8   6.3   3.4 | -19.4  -2.9  060  18  9   6.4   3.5
 17500 -18.4  -1.1  080  12  6   6.2   3.4 | -18.4  -1.1  055  18  9   6.5   3.6
 17000 -17.5   0.5  075   9  4   6.1   3.3 | -17.5   0.5  050  17  9   5.7   3.1
 16500 -16.6   2.1  065   5  3   6.1   3.3 | -16.7   1.9  045  17  9   5.7   3.1
 16000 -15.7   3.7  030   3  1   6.3   3.5 | -15.8   3.6  040  16  8   6.9   3.8
 15500 -14.7   5.5  325   3  1   6.3   3.5 | -14.6   5.7  025  12  6   8.0   4.4
 15000 -13.7   7.3  300   5  3   6.8   3.7 | -13.0   8.6  355  10  5   5.8   3.2
 14500 -12.7   9.1  295   6  3   7.0   3.8 | -12.2  10.0  345   9  5   5.3   2.9
 14000 -11.6  11.1  295   7  4   6.4   3.5 | -11.4  11.5  340   9  5   4.3   2.4
 13500 -10.8  12.6  305   7  4   5.6   3.1 | -10.8  12.6  345  10  5   3.9   2.1
 13000  -9.9  14.2  315   7  4   5.0   2.7 | -10.3  13.5  350  10  5   4.6   2.5
 12500  -9.4  15.1  330   8  4   3.6   2.0 |  -9.5  14.9  355  12  6   5.5   3.0
 12000  -8.9  16.0  340   9  5   4.1   2.3 |  -8.7  16.3  005  13  7   6.0   3.3
 11500  -8.2  17.2  350  11  6   5.4   3.0 |  -7.7  18.1  005  14  7   6.6   3.6
 11000  -7.4  18.7  355  13  7   5.8   3.2 |  -6.8  19.8  360  15  8   6.1   3.3
 10500  -6.5  20.3  360  15  8   6.5   3.6 |  -6.0  21.2  360  16  8   5.8   3.2
 10250  -6.0  21.2  360  16  8   7.2   4.0 |  -5.6  21.9  360  16  8   4.6   2.5
 10000  -5.6  21.9  360  17  9   4.2   2.3 |  -5.3  22.5  360  16  8   3.7   2.1
  9750  -5.3  22.5  005  17  9   4.7   2.6 |  -5.0  23.0  355  16  8   5.7   3.1
  9500  -4.8  23.4  005  17  9   8.1   4.4 |  -4.5  23.9  355  15  8   6.9   3.8
  9250  -4.3  24.3  005  17  9   6.8   3.8 |  -4.1  24.6  355  15  8   6.2   3.4
  9000  -3.8  25.2  010  17  9   5.5   3.0 |  -3.6  25.5  355  14  7   5.5   3.0
  8750  -3.4  25.9  015  15  8   6.2   3.4 |  -3.3  26.1  355  15  7   5.9   3.3
  8500  -2.9  26.8  020  14  7   7.6   4.2 |  -2.8  27.0  360  15  8   6.3   3.5
  8250  -2.4  27.7  025  13  7   7.1   3.9 |  -2.4  27.7  360  15  8   6.6   3.6
  8000  -1.9  28.6  030  14  7   7.0   3.9 |  -1.9  28.6  360  16  8   7.1   3.9
  7750  -1.4  29.5  030  14  7   6.7   3.7 |  -1.4  29.5  360  17  9   7.1   3.9
  7500  -0.9  30.4  030  15  8   6.6   3.6 |  -0.9  30.4  355  18  9   6.8   3.7
  7250  -0.4  31.3  030  16  8   7.7   4.2 |  -0.4  31.3  355  18  9   5.6   3.1
  7000   0.2  32.4  025  15  8   8.5   4.7 |  -0.0  32.0  355  18  9   5.1   2.8
  6750   0.8  33.4  020  14  7   7.9   4.3 |   0.3  32.5  350  19 10   5.3   2.9
  6500   1.4  34.5  015  13  7   9.2   5.1 |   0.8  33.4  350  18  9   8.2   4.5
  6250   2.1  35.8  015  12  6  10.8   5.9 |   1.5  34.7  345  17  9  10.4   5.7
  6000   2.9  37.2  010  11  6  10.6   5.8 |   2.2  36.0  345  16  8   9.8   5.4
  5750   3.7  38.7  010  11  5  10.7   5.9 |   2.9  37.2  340  14  7  10.2   5.6
  5500   4.5  40.1  010  10  5  12.5   6.9 |   3.7  38.7  340  12  6  11.8   6.5
________________________________________________________________________________

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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