Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 201248
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0548 MST Tuesday, January 20, 2015

This forecast is for Tuesday, January 20, 2015:

If the trigger temperature of 40.8 F/4.9 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 9472 ft MSL (4187 ft AGL)

Forecast maximum temperature................... 42.0 F/6.0 C
Time of trigger temperature.................... 1245 MST
Time of overdevelopment........................ 1700 MST
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................. 7494 ft MSL (2209 ft AGL)
Thermal soaring outlook for Wednesday 01/21.... 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....................... 30901 ft MSL (25616 ft AGL)
Wave soaring outlook for Wednesday 01/21....... Poor

Remarks... None

Sunrise/Sunset.................... 07:16:22 / 17:03:42 MST
Total possible sunshine........... 9 hr 47 min 20 sec (587 min 20 sec)
Altitude of sun at 12:10:25 MST... 30.23 degrees

Upper air data from rawinsonde observation taken on 01/20/2015 at 0500 MST

Freezing level.................. 5285 ft MSL (0 ft AGL)
Convective condensation level... 9137 ft MSL (3852 ft AGL)
Lifted condensation level....... 9558 ft MSL (4272 ft AGL)
Lifted index.................... +4.0
K index......................... +16.4

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  -53.3 -63.9   295   39   20  -2.2  -1.2  115.7 240.3    62.3      M    M
 45000  -57.5 -71.5   280   64   33  -6.4  -3.5   82.4 180.3    46.6      M    M
 40000  -53.6 -64.5   280   71   37  -6.6  -3.6   65.4 149.7    38.8      M    M
 38000  -53.9 -65.0   290   65   33  -6.2  -3.4   56.0 132.9    33.6      M    M
 36000  -56.3 -69.3   280   57   29   0.6   0.3   43.8 110.8    26.2      M    M
 34000  -55.4 -67.7   295   69   36  -2.7  -1.5   36.6  97.8    21.8      M    M
 32000  -54.6 -66.3   295   66   34   5.1   2.8   28.4  83.2    16.6      M    M
 30000  -52.8 -63.0   300   76   39  -2.6  -1.4   23.0  73.4    13.0      M    M
 29000  -51.4 -60.5   300   75   39   7.0   3.8   21.0  69.7    11.6      M    M
 28000  -48.8 -55.8   300   74   38   8.5   4.7   20.3  68.6    11.3      M    M
 27000  -46.3 -51.3   305   74   38   8.5   4.7   19.9  67.8    11.1      M    M
 26000  -43.7 -46.7   305   73   37   8.8   4.8   19.5  67.1    10.9      M    M
 25000  -41.0 -41.8   305   72   37   8.8   4.8   19.2  66.5    10.8      M    M
 24000  -38.4 -37.1   305   70   36   8.8   4.8   18.7  65.7    10.6      M    M
 23000  -35.7 -32.3   305   68   35   9.0   4.9   18.4  65.0    10.4      M    M
 22000  -33.0 -27.4   305   66   34   9.0   4.9   18.0  64.5    10.3      M    M
 21000  -30.3 -22.5   305   64   33   9.0   5.0   17.8  64.1    10.2      M    M
 20000  -27.6 -17.7   305   62   32   9.0   4.9   17.7  63.9    10.3      M    M
 19500  -26.2 -15.2   305   62   32   9.0   4.9   17.6  63.6    10.2      M    M
 19000  -25.5 -13.9   300   61   31   1.7   0.9   16.7  62.0     9.5      M    M
 18500  -25.4 -13.7   295   55   28  -1.2  -0.7   15.2  59.3     8.2      M    M
 18000  -25.3 -13.5   295   49   25   3.8   2.1   13.6  56.4     6.8      M    M
 17500  -24.6 -12.3   290   46   24   5.8   3.2   12.8  55.0     6.2      M    M
 17000  -23.5 -10.3   280   44   22   8.5   4.6   12.3  54.2     5.8      M    M
 16500  -22.2  -8.0   280   42   22   8.9   4.9   12.1  53.9     5.7      M    M
 16000  -20.9  -5.6   285   40   21   8.6   4.7   12.0  53.6     5.6      M    M
 15500  -19.0  -2.2   285   38   20   8.8   4.8   11.7  53.1     5.3      M    M
 15000  -17.7   0.1   285   37   19   8.8   4.8   11.5  52.7     5.2      M    M
 14500  -16.4   2.5   285   35   18   8.8   4.8   11.4  52.5     5.1      M    M
 14000  -15.1   4.8   285   34   17   8.7   4.8   11.2  52.2     5.0      M    M
 13500  -13.8   7.2   275   31   16   7.7   4.2   11.1  51.9     4.8      M    M
 13000  -13.1   8.4   270   29   15   3.7   2.0   10.3  50.5     4.1      M    M
 12500  -12.5   9.5   285   25   13   3.9   2.1    9.3  48.8     3.2      M    M
 12000  -11.6  11.1   300   22   12   8.3   4.6    8.8  47.8     2.7      M    M
 11500  -10.4  13.3   300   17    9   7.8   4.3    8.5  47.2     2.4      M    M
 11000   -9.4  15.1   295   13    7   7.4   4.1    8.1  46.6     2.0      M    M
 10500   -8.3  17.1   295   15    8   7.4   4.0    7.7  45.9     1.6      M    M
 10250   -7.8  18.0   295   15    8   7.4   4.0    7.5  45.5     1.4      M    M
 10000   -7.2  19.0   295   16    8   6.4   3.5    7.3  45.2     1.2      M    M
  9750   -6.9  19.6   290   15    8   1.6   0.9    6.9  44.4     0.8      M    M
  9500   -7.0  19.4   285   14    7  -2.6  -1.4    6.1  42.9     0.0      M    M
  9250   -7.1  19.2   275   13    7   2.4   1.3    5.2  41.4    -0.8    277  1.4
  9000   -6.7  19.9   270   12    6   6.7   3.7    4.9  40.8    -1.1    258  1.3
  8750   -6.2  20.8   265   10    5   6.0   3.3    4.6  40.3    -1.4    237  1.2
  8500   -5.8  21.6   260    7    4   6.2   3.4    4.3  39.8    -1.7    216  1.1
  8250   -5.3  22.5   245    5    3   6.1   3.3    4.0  39.3    -2.0    195  1.0
  8000   -4.9  23.2   220    4    2   6.4   3.5    3.8  38.8    -2.3    174  0.9
  7750   -4.4  24.1   205    2    1   5.3   2.9    3.5  38.3    -2.6    153  0.8
  7500   -4.1  24.6   115    1    1   3.5   1.9    3.1  37.5    -3.0    136  0.7
  7250   -3.9  25.0   075    3    1   3.4   1.9    2.6  36.6    -3.5    121  0.6
  7000   -3.6  25.5   065    5    3   3.5   1.9    2.1  35.8    -3.9    106  0.5
  6750   -3.3  26.1   065    6    3   3.4   1.9    1.6  34.9    -4.4     91  0.5
  6500   -3.1  26.4   060    7    4   3.6   2.0    1.1  34.0    -4.9     76  0.4
  6250   -2.8  27.0   060    9    4   2.8   1.5    0.7  33.2    -5.4     61  0.3
  6000   -2.6  27.3   060   10    5   6.0   3.3    0.2  32.3    -5.9     46  0.2
  5750   -1.9  28.6   055    8    4  11.4   6.2    0.1  32.3    -6.0     18  0.1
  5500   -1.0  30.2   050    6    3  11.8   6.5    0.3  32.5    -5.9      M    M

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

           01/20/2015 at 0800 MST          |       01/20/2015 at 1100 MST
                                           |
K index... +7.1  LI... +5.8                | K index... -12.8  LI... +6.3
CAPE... 0.0  CIN... -0.4                   | 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 -56.6 -69.9  290  35 18   1.0   0.5 | -56.3 -69.3  280  36 18   1.0   0.5
 45000 -55.1 -67.2  290  53 27   1.0   0.5 | -54.8 -66.6  290  53 28   0.9   0.5
 40000 -54.6 -66.3  290  57 30   0.2   0.1 | -56.8 -70.2  290  65 33  -1.7  -0.9
 38000 -54.7 -66.5  295  60 31  -2.7  -1.5 | -57.8 -72.0  290  69 36  -1.0  -0.6
 36000 -56.1 -69.0  295  68 35  -2.4  -1.3 | -58.4 -73.1  295  74 38  -1.1  -0.6
 34000 -57.6 -71.7  295  77 40  -2.5  -1.4 | -59.1 -74.4  295  80 41  -1.6  -0.9
 32000 -55.4 -67.7  300  82 42   5.2   2.9 | -55.7 -68.3  295  80 41   7.1   3.9
 30000 -51.9 -61.4  305  87 45   6.4   3.5 | -50.9 -59.6  295  79 41   7.4   4.1
 29000 -49.5 -57.1  305  85 44   8.0   4.4 | -48.7 -55.7  295  77 40   7.5   4.1
 28000 -47.1 -52.8  305  84 43   8.0   4.4 | -46.4 -51.5  295  75 38   7.5   4.1
 27000 -44.7 -48.5  305  82 42   8.0   4.4 | -44.2 -47.6  300  72 37   7.5   4.1
 26000 -42.3 -44.1  305  79 41   7.9   4.4 | -41.9 -43.4  300  70 36   7.8   4.3
 25000 -39.9 -39.8  305  76 39   7.9   4.4 | -39.5 -39.1  300  68 35   7.8   4.3
 24000 -37.5 -35.5  305  73 38   7.9   4.4 | -37.2 -35.0  300  66 34   7.8   4.3
 23000 -35.1 -31.2  305  70 36   8.5   4.7 | -34.8 -30.6  300  65 33   8.1   4.4
 22000 -32.5 -26.5  305  67 34   8.5   4.7 | -32.4 -26.3  300  63 32   8.1   4.4
 21000 -30.0 -22.0  305  63 33   8.6   4.7 | -30.0 -22.0  305  62 32   8.1   4.4
 20000 -27.7 -17.9  305  62 32   7.4   4.1 | -27.5 -17.5  305  59 30   8.4   4.6
 19500 -26.5 -15.7  305  61 31   7.4   4.1 | -26.2 -15.2  305  57 29   8.4   4.6
 19000 -25.4 -13.7  310  60 31   7.4   4.1 | -25.0 -13.0  305  56 29   8.4   4.6
 18500 -24.3 -11.7  310  59 31   7.6   4.1 | -23.7 -10.7  305  54 28   8.4   4.6
 18000 -23.3  -9.9  310  57 29   6.1   3.4 | -22.6  -8.7  305  52 27   6.6   3.6
 17500 -22.4  -8.3  305  53 27   6.2   3.4 | -21.6  -6.9  305  48 25   6.8   3.7
 17000 -21.5  -6.7  305  49 25   5.3   2.9 | -20.6  -5.1  300  45 23   5.8   3.2
 16500 -20.8  -5.4  300  46 24   4.7   2.6 | -19.8  -3.6  300  42 22   5.5   3.0
 16000 -20.1  -4.2  295  43 22   4.8   2.6 | -19.0  -2.2  300  39 20   5.5   3.0
 15500 -19.0  -2.2  295  39 20   5.3   2.9 | -18.1  -0.6  300  37 19   5.7   3.1
 15000 -18.2  -0.8  290  37 19   6.0   3.3 | -16.8   1.8  305  35 18   5.2   2.9
 14500 -17.3   0.9  290  35 18   6.4   3.5 | -16.1   3.0  305  35 18   5.1   2.8
 14000 -16.3   2.7  290  34 17   6.5   3.6 | -15.3   4.5  305  34 18   5.5   3.0
 13500 -15.4   4.3  295  33 17   6.6   3.6 | -14.5   5.9  305  33 17   5.9   3.2
 13000 -14.4   6.1  300  32 17   6.5   3.6 | -13.6   7.5  305  31 16   5.8   3.2
 12500 -13.5   7.7  300  31 16   6.3   3.4 | -12.8   9.0  305  30 16   5.7   3.1
 12000 -12.5   9.5  305  29 15   6.3   3.4 | -11.9  10.6  305  30 15   6.6   3.6
 11500 -11.6  11.1  310  27 14   6.3   3.4 | -10.8  12.6  305  29 15   7.7   4.2
 11000 -10.7  12.7  315  26 13   6.9   3.8 |  -9.7  14.5  310  29 15   6.6   3.6
 10500  -9.5  14.9  315  23 12   7.8   4.3 |  -8.9  16.0  310  27 14   6.0   3.3
 10250  -9.0  15.8  315  22 11   6.9   3.8 |  -8.5  16.7  310  26 14   4.6   2.5
 10000  -8.6  16.5  315  21 11   4.8   2.6 |  -8.2  17.2  310  26 13   3.3   1.8
  9750  -8.1  17.4  315  21 11   7.6   4.2 |  -7.9  17.8  310  25 13   6.5   3.5
  9500  -7.4  18.7  315  20 10  10.6   5.8 |  -7.3  18.9  310  24 12   9.1   5.0
  9250  -6.7  19.9  315  19 10   8.7   4.8 |  -6.7  19.9  310  23 12   6.9   3.8
  9000  -6.1  21.0  315  18  9   6.7   3.7 |  -6.3  20.7  310  21 11   4.6   2.5
  8750  -5.7  21.7  315  18  9   7.2   3.9 |  -5.9  21.4  315  20 10   6.1   3.4
  8500  -5.1  22.8  315  17  9   8.6   4.7 |  -5.4  22.3  315  18  9   7.5   4.1
  8250  -4.5  23.9  315  17  9   6.2   3.4 |  -4.8  23.4  320  16  8   7.1   3.9
  8000  -4.1  24.6  315  15  8   4.4   2.4 |  -4.3  24.3  320  14  7   7.2   3.9
  7750  -3.8  25.2  310  13  7   4.5   2.5 |  -3.8  25.2  325  12  6   7.0   3.8
  7500  -3.5  25.7  305  12  6   4.3   2.4 |  -3.3  26.1  330  10  5   6.8   3.8
  7250  -3.2  26.2  300  10  5   4.9   2.7 |  -2.8  27.0  330   9  4   6.8   3.7
  7000  -2.8  27.0  295   8  4   5.1   2.8 |  -2.3  27.9  330   7  4   7.0   3.8
  6750  -2.5  27.5  280   6  3   4.7   2.6 |  -1.8  28.8  330   6  3   6.3   3.5
  6500  -2.2  28.0  270   4  2   4.1   2.2 |  -1.4  29.5  325   5  2   5.5   3.0
  6250  -1.9  28.6  260   4  2   4.5   2.5 |  -1.0  30.2  300   3  1   5.7   3.1
  6000  -1.6  29.1  245   4  2   3.2   1.8 |  -0.7  30.7  245   2  1   5.8   3.2
  5750  -1.5  29.3  230   4  2   2.1   1.1 |  -0.2  31.6  215   3  2  10.3   5.7
  5500  -1.3  29.7  220   3  2   3.9   2.1 |   0.9  33.6  210   3  2  17.3   9.5

           01/20/2015 at 1400 MST          |       01/20/2015 at 1700 MST
                                           |
K index... -12.5  LI... +5.8               | K index... -6.2  LI... +4.7
CAPE... 0.0  CIN... -0.5                   | 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 -57.2 -71.0  280  36 19   1.4   0.8 | -57.2 -71.0  285  36 18   1.3   0.7
 45000 -55.0 -67.0  290  56 29   1.4   0.8 | -55.3 -67.5  290  53 27   1.3   0.7
 40000 -57.3 -71.1  285  71 37  -2.0  -1.1 | -57.1 -70.8  285  75 38  -1.6  -0.9
 38000 -58.4 -73.1  285  77 39  -0.4  -0.2 | -58.0 -72.4  285  82 42  -1.1  -0.6
 36000 -58.8 -73.8  285  79 41  -0.6  -0.3 | -58.7 -73.7  280  82 42  -1.1  -0.6
 34000 -59.1 -74.4  290  81 42  -1.1  -0.6 | -59.3 -74.7  280  82 42  -1.6  -0.9
 32000 -55.7 -68.3  290  81 42   7.1   3.9 | -55.8 -68.4  280  80 41   7.4   4.1
 30000 -50.9 -59.6  290  80 41   7.7   4.2 | -51.4 -60.5  280  77 40   7.4   4.1
 29000 -48.5 -55.3  290  78 40   8.0   4.4 | -48.2 -54.8  280  75 39   8.7   4.8
 28000 -46.1 -51.0  290  76 39   8.0   4.4 | -45.6 -50.1  285  74 38   8.7   4.8
 27000 -43.6 -46.5  290  74 38   8.1   4.4 | -43.0 -45.4  285  72 37   8.7   4.8
 26000 -41.4 -42.5  290  71 36   7.3   4.0 | -40.8 -41.4  285  69 36   6.7   3.7
 25000 -39.2 -38.6  290  67 34   7.3   4.0 | -38.8 -37.8  285  65 33   6.7   3.7
 24000 -37.0 -34.6  290  62 32   7.3   4.0 | -36.8 -34.2  290  60 31   6.7   3.7
 23000 -34.8 -30.6  295  59 30   7.6   4.2 | -34.7 -30.5  290  57 29   7.4   4.0
 22000 -32.5 -26.5  295  56 29   7.6   4.2 | -32.5 -26.5  290  54 28   7.4   4.1
 21000 -30.2 -22.4  295  54 28   7.7   4.2 | -30.3 -22.5  290  51 26   7.4   4.0
 20000 -27.7 -17.9  295  52 27   8.7   4.8 | -28.0 -18.4  290  49 25   7.7   4.2
 19500 -26.4 -15.5  295  51 26   8.7   4.8 | -26.8 -16.2  290  48 25   7.7   4.2
 19000 -25.1 -13.2  295  50 26   8.7   4.8 | -25.7 -14.3  290  47 24   7.7   4.2
 18500 -23.8 -10.8  295  49 25   8.7   4.8 | -24.5 -12.1  295  46 24   7.5   4.1
 18000 -22.5  -8.5  295  48 25   8.1   4.4 | -23.2  -9.8  295  45 23   9.4   5.1
 17500 -21.3  -6.3  295  47 24   8.2   4.5 | -21.8  -7.2  295  44 23   9.2   5.1
 17000 -20.1  -4.2  300  46 24   7.3   4.0 | -20.5  -4.9  295  43 22   7.4   4.1
 16500 -19.0  -2.2  300  46 23   7.0   3.8 | -19.5  -3.1  295  41 21   6.5   3.6
 16000 -18.0  -0.4  300  45 23   6.3   3.5 | -18.5  -1.3  295  40 21   6.1   3.3
 15500 -17.2   1.0  300  42 21   4.9   2.7 | -17.8  -0.0  295  39 20   4.9   2.7
 15000 -16.1   3.0  300  37 19   4.6   2.5 | -17.0   1.4  295  37 19   4.9   2.7
 14500 -15.4   4.3  300  36 18   4.5   2.5 | -16.2   2.8  295  35 18   3.6   2.0
 14000 -14.8   5.4  300  35 18   4.6   2.5 | -15.7   3.7  295  33 17   4.0   2.2
 13500 -14.1   6.6  300  33 17   4.7   2.6 | -15.0   5.0  295  31 16   4.7   2.6
 13000 -13.4   7.9  300  32 16   5.2   2.8 | -14.4   6.1  295  30 15   5.2   2.9
 12500 -12.6   9.3  300  30 16   5.8   3.2 | -13.5   7.7  295  27 14   6.1   3.3
 12000 -11.7  10.9  300  29 15   5.5   3.0 | -12.7   9.1  295  24 12   6.5   3.6
 11500 -11.0  12.2  300  26 14   4.9   2.7 | -11.6  11.1  295  21 11   7.2   4.0
 11000 -10.4  13.3  300  23 12   6.0   3.3 | -10.6  12.9  300  17  9   7.0   3.8
 10500  -9.4  15.1  300  21 11   7.2   3.9 |  -9.6  14.7  300  15  8   6.9   3.8
 10250  -8.8  16.2  300  19 10   6.1   3.4 |  -9.1  15.6  305  13  7   5.9   3.2
 10000  -8.5  16.7  300  18  9   4.5   2.5 |  -8.7  16.3  305  13  6   5.0   2.7
  9750  -8.1  17.4  300  18  9   7.5   4.1 |  -8.3  17.1  310  12  6   8.0   4.4
  9500  -7.4  18.7  305  16  8  10.2   5.6 |  -7.5  18.5  310  11  5  10.4   5.7
  9250  -6.7  19.9  305  14  7   8.1   4.5 |  -6.8  19.8  315   9  5   8.7   4.7
  9000  -6.2  20.8  305  13  7   5.8   3.2 |  -6.3  20.7  320   8  4   6.5   3.6
  8750  -5.7  21.7  310  12  6   6.8   3.7 |  -5.8  21.6  325   7  4   7.1   3.9
  8500  -5.2  22.6  310  11  6   8.2   4.5 |  -5.2  22.6  335   6  3   8.1   4.5
  8250  -4.6  23.7  315   9  5   7.2   3.9 |  -4.6  23.7  340   5  3   7.4   4.1
  8000  -4.1  24.6  315   7  4   6.7   3.7 |  -4.1  24.6  355   4  2   7.0   3.8
  7750  -3.6  25.5  320   5  3   6.3   3.5 |  -3.6  25.5  010   3  2   7.8   4.3
  7500  -3.2  26.2  325   3  1   7.1   3.9 |  -3.0  26.6  020   2  1   8.5   4.7
  7250  -2.6  27.3  325   2  1   9.3   5.1 |  -2.3  27.9  035   2  1   8.8   4.8
  7000  -1.8  28.8  320   1  1  10.0   5.5 |  -1.7  28.9  045   2  1   8.9   4.9
  6750  -1.1  30.0  305   1  1   9.1   5.0 |  -1.0  30.2  060   1  1   9.1   5.0
  6500  -0.5  31.1  305   1  1   9.5   5.2 |  -0.3  31.5  060   2  1   9.9   5.4
  6250   0.3  32.5  300   1  1  10.6   5.8 |   0.4  32.7  055   1  1  10.3   5.6
  6000   1.1  34.0  300   1  0   9.9   5.4 |   1.2  34.2  050   1  1  10.3   5.6
  5750   1.8  35.2  295   1  0  11.8   6.5 |   1.9  35.4  050   1  1   8.8   4.8
  5500   2.9  37.2  290   1  0  16.2   8.9 |   2.4  36.3  055   1  1   6.2   3.4
________________________________________________________________________________

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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