Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 260033
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1733 MST Tuesday, November 25, 2014

This forecast is for Wednesday, November 26, 2014:

If the trigger temperature of 49.2 F/9.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 9800 ft MSL (4513 ft AGL)

Forecast maximum temperature................... 51.0 F/11.0 C
Time of trigger temperature.................... 1300 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8506 ft MSL (3219 ft AGL)
Thermal soaring outlook for Thursday 11/27..... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Increasing
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 14654 ft MSL (9367 ft AGL)
Wave soaring outlook for Thursday 11/27........ Good

Remarks... None

Sunrise/Sunset.................... 06:56:23 / 16:37:14 MST
Total possible sunshine........... 9 hr 40 min 52 sec (580 min 52 sec)
Altitude of sun at 11:46:58 MST... 29.26 degrees

Upper air data from numerical model forecast valid on 11/26/2014 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 14224 ft MSL (8937 ft AGL)
Lifted condensation level....... 11502 ft MSL (6215 ft AGL)
Lifted index.................... +9.2
K index......................... +10.2

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -61.1 -78.0   315   70   36   0.3   0.2      M     M       M      M    M
 45000  -60.6 -77.1   325   72   37  -0.3  -0.2      M     M       M      M    M
 40000  -64.2 -83.6   320   94   48  -2.5  -1.4      M     M       M      M    M
 38000  -62.2 -80.0   315   98   51   8.9   4.9      M     M       M      M    M
 36000  -56.9 -70.4   315   98   50   8.9   4.9      M     M       M      M    M
 34000  -50.9 -59.6   315   94   49   8.6   4.7      M     M       M      M    M
 32000  -45.7 -50.3   320   85   44   8.6   4.7      M     M       M      M    M
 30000  -40.6 -41.1   325   81   42   8.3   4.5   36.3  97.4    19.4      M    M
 29000  -38.1 -36.6   330   83   43   8.2   4.5   35.7  96.2    19.1      M    M
 28000  -35.7 -32.3   330   86   44   8.2   4.5   35.1  95.2    18.9      M    M
 27000  -33.2 -27.8   335   88   45   6.8   3.7   34.6  94.3    18.8      M    M
 26000  -31.4 -24.5   335   87   45   6.0   3.3   33.1  91.5    17.8      M    M
 25000  -29.6 -21.3   335   85   44   6.0   3.3   31.7  89.0    16.8      M    M
 24000  -27.8 -18.0   335   84   43   6.1   3.4   30.4  86.7    16.0      M    M
 23000  -25.9 -14.6   335   82   42   6.5   3.6   29.1  84.3    15.1      M    M
 22000  -24.0 -11.2   335   80   41   6.6   3.6   27.9  82.2    14.3      M    M
 21000  -22.1  -7.8   335   78   40   5.2   2.9   26.8  80.3    13.5      M    M
 20000  -20.7  -5.3   335   75   39   4.5   2.5   24.8  76.7    12.0      M    M
 19500  -20.1  -4.2   330   74   38   4.5   2.5   23.9  75.1    11.2      M    M
 19000  -19.4  -2.9   330   72   37   4.6   2.5   23.0  73.5    10.5      M    M
 18500  -18.7  -1.7   330   71   37   5.4   3.0   22.2  71.9     9.8      M    M
 18000  -17.8  -0.0   325   69   36   6.6   3.6   21.6  70.9     9.4      M    M
 17500  -16.8   1.8   325   67   35   6.5   3.6   21.1  69.9     9.0      M    M
 17000  -15.8   3.6   325   66   34   7.5   4.1   20.6  69.1     8.6      M    M
 16500  -14.1   6.6   325   63   33   7.4   4.1   20.0  68.0     8.1      M    M
 16000  -13.0   8.6   325   63   32   7.5   4.1   19.6  67.3     7.8      M    M
 15500  -11.9  10.6   325   64   33   7.5   4.1   19.2  66.6     7.5      M    M
 15000  -10.8  12.6   325   64   33   7.3   4.0   18.8  65.9     7.2      M    M
 14500   -9.7  14.5   325   65   33   7.4   4.1   18.4  65.2     6.8      M    M
 14000   -8.7  16.3   320   65   33   6.3   3.5   18.0  64.4     6.4      M    M
 13500   -7.8  18.0   320   63   32   6.0   3.3   17.4  63.3     5.9      M    M
 13000   -6.9  19.6   320   61   32   5.5   3.0   16.8  62.2     5.3      M    M
 12500   -6.1  21.0   315   61   31   5.2   2.9   16.0  60.8     4.6      M    M
 12000   -5.4  22.3   315   60   31   4.6   2.5   15.3  59.5     4.0      M    M
 11500   -4.8  23.4   315   58   30   4.2   2.3   14.3  57.8     3.1      M    M
 11000   -4.2  24.4   310   56   29   3.9   2.2   13.4  56.2     2.3      M    M
 10500   -3.6  25.5   310   52   27   4.0   2.2   12.5  54.5     1.4      M    M
 10250   -3.4  25.9   310   50   26   3.3   1.8   12.0  53.6     0.9      M    M
 10000   -3.2  26.2   310   49   25   2.3   1.3   11.5  52.6     0.4      M    M
  9750   -3.0  26.6   305   47   24   3.1   1.7   10.9  51.6    -0.2    306  1.6
  9500   -2.7  27.1   305   45   23   4.2   2.3   10.4  50.8    -0.6    291  1.5
  9250   -2.4  27.7   305   42   22   2.9   1.6   10.0  49.9    -1.1    275  1.4
  9000   -2.3  27.9   300   39   20   1.1   0.6    9.3  48.8    -1.7    264  1.3
  8750   -2.3  27.9   300   35   18   0.7   0.4    8.6  47.6    -2.4    255  1.3
  8500   -2.2  28.0   300   31   16   1.5   0.8    8.0  46.3    -3.0    245  1.2
  8250   -2.1  28.2   300   26   13  -1.7  -0.9    7.3  45.1    -3.7    237  1.2
  8000   -2.4  27.7   295   20   10  -4.1  -2.3    6.2  43.2    -4.8    238  1.2
  7750   -2.7  27.1   295   14    7  -4.7  -2.6    5.2  41.3    -5.8    239  1.2
  7500   -3.1  26.4   290    8    4  -4.5  -2.5    4.0  39.2    -7.0    244  1.2
  7250   -3.4  25.9   265    4    2  -1.8  -1.0    3.0  37.4    -7.9    243  1.2
  7000   -3.5  25.7   200    3    2  -0.7  -0.4    2.2  35.9    -8.8    239  1.2
  6750   -3.6  25.5   160    6    3  -3.1  -1.7    1.3  34.4    -9.6    234  1.2
  6500   -3.7  25.3   150    9    4   2.8   1.5    0.4  32.8   -10.6    232  1.2
  6250   -3.1  26.4   150    9    5   9.2   5.0    0.3  32.5   -10.7    207  1.1
  6000   -2.6  27.3   150   10    5   7.9   4.4    0.1  32.3   -10.9    182  0.9
  5750   -1.9  28.6   150   10    5   8.7   4.7    0.1  32.1   -11.0    156  0.8
  5500   -1.4  29.5   145    8    4   6.7   3.7   -0.0  31.9   -11.2    131  0.7

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

           11/26/2014 at 0800 MST          |       11/26/2014 at 1100 MST
                                           |
K index... +8.9  LI... +4.4                | K index... +8.7  LI... +4.1
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.5
                                           |
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 -61.4 -78.5  315  60 31   0.3   0.2 | -61.4 -78.5  315  58 30   0.1   0.1
 45000 -60.9 -77.6  325  72 37  -0.3  -0.1 | -61.2 -78.2  320  73 37  -1.4  -0.8
 40000 -64.2 -83.6  320  91 47  -2.2  -1.2 | -63.4 -82.1  320  81 42  -1.5  -0.8
 38000 -61.5 -78.7  320  91 47   8.5   4.7 | -60.7 -77.3  320  81 42   8.0   4.4
 36000 -56.4 -69.5  320  85 44   8.5   4.7 | -55.9 -68.6  320  79 41   8.0   4.4
 34000 -51.2 -60.2  320  81 42   9.3   5.1 | -51.0 -59.8  320  78 40   8.8   4.8
 32000 -45.7 -50.3  325  81 42   9.3   5.1 | -45.7 -50.3  320  75 39   8.8   4.8
 30000 -40.3 -40.5  330  81 42   8.0   4.4 | -39.9 -39.8  325  74 38   8.3   4.5
 29000 -38.0 -36.4  330  82 42   7.9   4.3 | -37.4 -35.3  330  74 38   8.3   4.5
 28000 -35.6 -32.1  335  83 43   7.9   4.3 | -34.9 -30.8  330  75 39   8.3   4.6
 27000 -32.7 -26.9  335  83 43   6.4   3.5 | -32.5 -26.5  335  74 38   7.3   4.0
 26000 -30.8 -23.4  335  75 38   6.5   3.6 | -30.3 -22.5  330  66 34   7.4   4.1
 25000 -28.9 -20.0  335  67 34   6.5   3.6 | -28.0 -18.4  330  59 30   7.4   4.1
 24000 -26.9 -16.4  330  59 30   5.9   3.2 | -25.9 -14.6  330  52 27   6.2   3.4
 23000 -25.3 -13.5  330  53 27   5.6   3.0 | -24.1 -11.4  325  48 25   5.9   3.2
 22000 -23.7 -10.7  325  46 24   5.6   3.1 | -22.4  -8.3  315  45 23   6.0   3.3
 21000 -22.0  -7.6  320  43 22   6.1   3.4 | -20.7  -5.3  315  44 22   4.6   2.5
 20000 -20.2  -4.4  325  51 26   6.1   3.4 | -19.3  -2.7  320  49 25   4.7   2.6
 19500 -19.3  -2.7  330  56 29   6.1   3.4 | -18.6  -1.5  320  52 27   4.7   2.6
 19000 -18.4  -1.1  330  60 31   6.1   3.4 | -17.9  -0.2  325  55 28   4.7   2.6
 18500 -17.5   0.5  330  64 33   6.2   3.4 | -17.2   1.0  325  57 29   5.7   3.1
 18000 -16.5   2.3  330  62 32   6.3   3.4 | -16.3   2.7  325  56 29   5.9   3.2
 17500 -15.6   3.9  330  61 31   6.3   3.5 | -15.5   4.1  330  55 28   6.0   3.3
 17000 -14.6   5.7  330  60 31   6.5   3.6 | -14.5   5.9  330  55 28   6.5   3.5
 16500 -13.7   7.3  330  59 30   6.5   3.5 | -13.6   7.5  330  55 29   6.4   3.5
 16000 -12.7   9.1  330  58 30   6.7   3.7 | -12.6   9.3  330  55 29   6.7   3.7
 15500 -11.7  10.9  330  58 30   6.7   3.7 | -11.6  11.1  330  55 28   6.7   3.7
 15000 -10.7  12.7  330  57 30   6.6   3.6 | -10.1  13.8  330  54 28   7.2   3.9
 14500  -9.8  14.4  330  57 30   6.5   3.6 |  -9.0  15.8  330  53 27   7.0   3.9
 14000  -8.3  17.1  330  58 30   7.0   3.8 |  -7.9  17.8  325  53 27   8.0   4.4
 13500  -7.3  18.9  325  58 30   7.0   3.8 |  -6.7  19.9  325  52 27   7.9   4.4
 13000  -6.3  20.7  325  58 30   6.4   3.5 |  -5.6  21.9  325  52 27   7.4   4.1
 12500  -5.4  22.3  325  57 29   6.4   3.5 |  -4.5  23.9  325  51 26   7.5   4.1
 12000  -4.5  23.9  325  56 29   4.9   2.7 |  -3.5  25.7  325  51 26   6.1   3.4
 11500  -3.9  25.0  320  55 28   4.6   2.5 |  -2.6  27.3  320  50 26   6.1   3.4
 11000  -3.2  26.2  320  54 28   4.1   2.2 |  -1.8  28.8  320  49 25   4.6   2.5
 10500  -2.7  27.1  315  51 26   4.4   2.4 |  -1.2  29.8  315  48 25   4.9   2.7
 10250  -2.4  27.7  315  50 26   2.3   1.3 |  -0.8  30.6  315  47 24   2.7   1.5
 10000  -2.3  27.9  315  50 26   1.5   0.8 |  -0.7  30.7  315  47 24   1.7   1.0
  9750  -2.1  28.2  315  48 25   3.8   2.1 |  -0.5  31.1  310  46 24   3.4   1.9
  9500  -1.8  28.8  310  46 24   4.5   2.4 |  -0.3  31.5  310  46 24   3.4   1.9
  9250  -1.5  29.3  310  44 22   2.9   1.6 |  -0.0  32.0  305  45 23   2.6   1.4
  9000  -1.4  29.5  310  41 21   1.2   0.7 |   0.1  32.2  305  44 23   2.3   1.3
  8750  -1.3  29.7  310  38 20   1.8   1.0 |   0.3  32.5  305  42 22   3.8   2.1
  8500  -1.2  29.8  310  35 18   1.7   0.9 |   0.6  33.1  300  40 20   4.2   2.3
  8250  -1.1  30.0  310  31 16   0.1   0.1 |   0.9  33.6  300  37 19   3.7   2.0
  8000  -1.2  29.8  310  26 14  -0.8  -0.5 |   1.2  34.2  300  34 17   3.1   1.7
  7750  -1.2  29.8  310  22 11  -0.8  -0.4 |   1.4  34.5  300  30 16   5.2   2.9
  7500  -1.3  29.7  310  17  9  -0.7  -0.4 |   1.8  35.2  300  27 14   2.2   1.2
  7250  -1.3  29.7  310  12  6  -0.0  -0.0 |   1.7  35.1  295  22 11  -2.4  -1.3
  7000  -1.3  29.7  310   8  4  -0.5  -0.3 |   1.6  34.9  295  17  9  -1.6  -0.9
  6750  -1.3  29.7  315   3  1   1.2   0.6 |   1.4  34.5  290  11  6  -2.4  -1.3
  6500  -1.1  30.0  135   1  0   3.0   1.6 |   1.3  34.3  285   7  4   2.0   1.1
  6250  -0.9  30.4  135   4  2   3.5   1.9 |   1.7  35.1  270   5  2   5.3   2.9
  6000  -0.7  30.7  135   7  4   1.1   0.6 |   2.0  35.6  235   3  1   5.4   3.0
  5750  -0.8  30.6  130   9  4  -3.2  -1.7 |   2.6  36.7  190   3  1  10.2   5.6
  5500  -1.1  30.0  125   6  3  -2.8  -1.5 |   3.5  38.3  180   3  1  13.8   7.5

           11/26/2014 at 1400 MST          |       11/26/2014 at 1700 MST
                                           |
K index... +7.1  LI... +5.1                | K index... +9.6  LI... +4.1
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 -62.9 -81.2  310  54 28  -1.2  -0.6 | -62.7 -80.9  315  61 32  -1.2  -0.6
 45000 -64.5 -84.1  315  65 34   1.3   0.7 | -64.4 -83.9  315  77 40   0.9   0.5
 40000 -62.8 -81.0  320  70 36   1.2   0.6 | -63.4 -82.1  315  69 36   0.8   0.4
 38000 -59.9 -75.8  315  70 36   7.0   3.8 | -60.0 -76.0  315  66 34   7.9   4.4
 36000 -55.7 -68.3  310  68 35   7.0   3.8 | -55.2 -67.4  315  63 32   7.9   4.3
 34000 -51.1 -60.0  310  67 35   9.2   5.0 | -50.4 -58.7  315  60 31   8.3   4.6
 32000 -45.5 -49.9  315  66 34   9.2   5.1 | -45.4 -49.7  315  59 30   8.3   4.6
 30000 -40.0 -40.0  320  65 34   6.8   3.7 | -40.1 -40.2  320  58 30   7.0   3.9
 29000 -37.9 -36.2  325  66 34   6.8   3.7 | -38.0 -36.4  325  58 30   7.0   3.9
 28000 -35.9 -32.6  335  67 34   6.8   3.7 | -35.9 -32.6  330  59 30   7.1   3.9
 27000 -33.7 -28.7  335  66 34   8.5   4.7 | -33.6 -28.5  330  58 30   8.8   4.8
 26000 -31.2 -24.2  335  61 31   8.4   4.6 | -31.0 -23.8  330  56 29   8.7   4.8
 25000 -28.7 -19.7  330  56 29   8.4   4.6 | -28.4 -19.1  325  54 28   8.8   4.8
 24000 -26.2 -15.2  330  51 26   8.1   4.4 | -26.0 -14.8  320  53 27   5.6   3.1
 23000 -23.8 -10.8  330  47 24   8.0   4.4 | -24.2 -11.6  320  51 26   5.9   3.2
 22000 -21.4  -6.5  330  43 22   8.1   4.4 | -22.5  -8.5  325  48 25   5.9   3.2
 21000 -19.3  -2.7  330  43 22   4.9   2.7 | -20.7  -5.3  325  46 24   6.5   3.6
 20000 -17.7   0.1  335  52 27   5.2   2.8 | -18.8  -1.8  325  43 22   6.5   3.6
 19500 -17.0   1.4  340  56 29   5.2   2.9 | -17.8  -0.0  320  42 22   6.5   3.6
 19000 -16.2   2.8  340  61 31   5.2   2.9 | -16.8   1.8  320  41 21   6.4   3.5
 18500 -15.4   4.3  340  64 33   4.8   2.6 | -15.8   3.6  320  38 20   7.8   4.3
 18000 -14.7   5.5  340  63 33   4.9   2.7 | -14.6   5.7  315  35 18   7.7   4.2
 17500 -14.0   6.8  340  63 32   5.4   3.0 | -13.5   7.7  310  32 17   6.8   3.7
 17000 -13.1   8.4  340  62 32   6.4   3.5 | -12.6   9.3  305  31 16   6.0   3.3
 16500 -12.2  10.0  340  61 31   6.4   3.5 | -11.8  10.8  305  30 15   6.0   3.3
 16000 -11.2  11.8  335  60 31   6.6   3.6 | -10.9  12.4  305  30 16   5.7   3.2
 15500 -10.2  13.6  335  59 30   6.5   3.6 | -10.1  13.8  310  31 16   5.6   3.1
 15000  -8.8  16.2  335  58 30   6.8   3.7 |  -8.6  16.5  320  33 17   7.3   4.0
 14500  -7.8  18.0  335  57 30   6.8   3.7 |  -7.5  18.5  320  35 18   7.3   4.0
 14000  -6.8  19.8  335  57 29   6.5   3.6 |  -6.4  20.5  325  36 19   7.0   3.9
 13500  -5.8  21.6  335  56 29   6.5   3.6 |  -5.4  22.3  325  37 19   7.0   3.8
 13000  -4.8  23.4  335  54 28   6.8   3.8 |  -4.3  24.3  325  38 20   7.7   4.2
 12500  -3.8  25.2  335  53 27   6.9   3.8 |  -3.2  26.2  325  40 20   7.8   4.3
 12000  -2.8  27.0  335  51 26   6.6   3.6 |  -2.1  28.2  325  41 21   6.7   3.7
 11500  -1.9  28.6  330  49 25   6.7   3.7 |  -1.1  30.0  330  41 21   6.9   3.8
 11000  -1.0  30.2  330  47 24   5.0   2.8 |  -0.1  31.8  325  41 21   6.0   3.3
 10500  -0.3  31.5  325  45 23   5.6   3.1 |   0.8  33.4  325  40 21   6.7   3.7
 10250   0.1  32.2  320  44 23   2.5   1.4 |   1.2  34.2  325  40 21   2.3   1.2
 10000   0.2  32.4  320  44 23   2.2   1.2 |   1.2  34.2  325  40 21   2.3   1.3
  9750   0.5  32.9  315  43 22   5.0   2.8 |   1.6  34.9  320  39 20   6.6   3.6
  9500   0.8  33.4  315  41 21   4.5   2.5 |   2.0  35.6  320  39 20   5.1   2.8
  9250   1.1  34.0  310  40 21   2.9   1.6 |   2.3  36.1  320  38 20   2.2   1.2
  9000   1.2  34.2  305  39 20   1.8   1.0 |   2.4  36.3  315  37 19   0.6   0.3
  8750   1.4  34.5  305  37 19   2.8   1.5 |   2.5  36.5  315  36 19   1.8   1.0
  8500   1.6  34.9  300  35 18   3.4   1.9 |   2.6  36.7  310  35 18   2.2   1.2
  8250   1.9  35.4  300  33 17   5.1   2.8 |   2.8  37.0  305  34 17   2.7   1.5
  8000   2.3  36.1  295  30 15   5.9   3.2 |   3.0  37.4  305  31 16   2.9   1.6
  7750   2.8  37.0  295  27 14   6.5   3.6 |   3.2  37.8  300  29 15   3.6   2.0
  7500   3.3  37.9  295  24 12   7.7   4.2 |   3.5  38.3  300  27 14   5.5   3.0
  7250   3.9  39.0  295  22 11   8.0   4.4 |   4.0  39.2  300  24 12   6.4   3.5
  7000   4.5  40.1  295  19 10   7.9   4.3 |   4.4  39.9  295  21 11   6.1   3.3
  6750   5.1  41.2  295  17  9   7.7   4.2 |   4.9  40.8  295  19 10   7.0   3.8
  6500   5.6  42.1  295  14  7   8.5   4.7 |   5.5  41.9  295  16  8   7.5   4.1
  6250   6.3  43.3  295  11  6   9.0   4.9 |   6.0  42.8  295  14  7   7.0   3.9
  6000   7.0  44.6  295   9  5   9.7   5.3 |   6.5  43.7  295  11  6   7.7   4.2
  5750   7.7  45.9  295   7  4  10.7   5.9 |   7.1  44.8  295   9  4   5.8   3.2
  5500   8.5  47.3  295   6  3   9.7   5.3 |   7.3  45.1  290   5  3   0.9   0.5
________________________________________________________________________________

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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