Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 120116
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1916 MDT Thursday, September 11, 2014

This forecast is for Friday, September 12, 2014:

If the trigger temperature of 43.5 F/6.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 10457 ft MSL (5143 ft AGL)

Forecast maximum temperature................... 49.0 F/9.9 C
Time of trigger temperature.................... 1145 MDT
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................. 9279 ft MSL (3965 ft AGL)
Thermal soaring outlook for Saturday 09/13..... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... 11969 ft MSL (6655 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 45738 ft MSL (40424 ft AGL)
Wave soaring outlook for Saturday 09/13........ Fair

Remarks...

Sunrise/Sunset.................... 06:37:45 / 19:14:28 MDT
Total possible sunshine........... 12 hr 36 min 43 sec (756 min 43 sec)
Altitude of sun at 12:55:37 MDT... 54.22 degrees

Upper air data from numerical model forecast valid on 09/12/2014 at 0600 MDT

Freezing level.................. 6166 ft MSL (852 ft AGL)
Convective condensation level... 8246 ft MSL (2932 ft AGL)
Lifted condensation level....... 10139 ft MSL (4825 ft AGL)
Lifted index.................... +14.4
K index......................... -9.9

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  -62.5 -80.5   275   57   29   1.8   1.0      M     M       M      M    M
 45000  -59.1 -74.4   275   85   44   4.3   2.4      M     M       M      M    M
 40000  -52.6 -62.7   280   83   43   4.2   2.3      M     M       M      M    M
 38000  -50.3 -58.5   280   79   40   3.9   2.1      M     M       M      M    M
 36000  -47.7 -53.9   280   74   38   3.9   2.1      M     M       M      M    M
 34000  -44.4 -47.9   280   68   35   6.3   3.5      M     M       M      M    M
 32000  -40.6 -41.1   280   62   32   6.3   3.4      M     M       M      M    M
 30000  -36.3 -33.3   280   58   30   7.8   4.3   40.6 105.1    23.5      M    M
 29000  -34.0 -29.2   280   57   29   7.8   4.3   39.8 103.7    23.2      M    M
 28000  -31.6 -24.9   280   56   29   7.8   4.3   39.2 102.5    23.0      M    M
 27000  -29.3 -20.7   280   55   28   8.0   4.4   38.4 101.2    22.7      M    M
 26000  -26.9 -16.4   280   55   28   8.0   4.4   37.7  99.9    22.4      M    M
 25000  -24.5 -12.1   285   54   28   8.1   4.4   37.1  98.8    22.1      M    M
 24000  -21.9  -7.4   285   53   27   8.7   4.8   36.6  97.9    22.0      M    M
 23000  -19.3  -2.7   285   52   27   8.7   4.8   36.2  97.2    21.9      M    M
 22000  -16.7   1.9   285   51   26   8.7   4.8   35.9  96.6    21.9      M    M
 21000  -14.6   5.7   285   50   26   5.2   2.8   34.8  94.6    21.3      M    M
 20000  -13.1   8.4   285   50   26   5.1   2.8   33.1  91.6    20.1      M    M
 19500  -12.4   9.7   285   50   26   5.1   2.8   32.3  90.1    19.5      M    M
 19000  -11.6  11.1   285   50   26   5.3   2.9   31.5  88.7    18.9      M    M
 18500  -10.2  13.6   285   49   25   6.3   3.5   30.6  87.0    18.3      M    M
 18000   -9.3  15.3   285   49   25   6.4   3.5   30.0  86.0    17.9      M    M
 17500   -8.3  17.1   285   48   25   6.6   3.6   29.4  85.0    17.5      M    M
 17000   -7.3  18.9   280   48   25   6.7   3.7   28.9  84.0    17.1      M    M
 16500   -6.4  20.5   280   48   25   5.0   2.7   28.2  82.8    16.6      M    M
 16000   -5.7  21.7   280   47   24   5.0   2.7   27.4  81.3    15.9      M    M
 15500   -5.0  23.0   275   47   24   5.4   2.9   26.6  80.0    15.3      M    M
 15000   -4.3  24.3   275   45   23   5.7   3.1   25.9  78.7    14.6      M    M
 14500   -3.5  25.7   270   43   22   5.6   3.1   25.3  77.5    14.0      M    M
 14000   -2.9  26.8   270   40   20   4.3   2.3   24.4  76.0    13.2      M    M
 13500   -2.3  27.9   270   37   19   4.1   2.3   23.6  74.4    12.4      M    M
 13000   -2.3  27.9   270   34   17  -2.7  -1.5   22.0  71.6    11.0      M    M
 12500   -2.6  27.3   270   31   16  -1.9  -1.1   20.1  68.1     9.3      M    M
 12000   -3.3  26.1   270   27   14  -7.0  -3.9   17.7  63.9     7.1      M    M
 11500   -4.3  24.3   275   22   11  -6.6  -3.6   15.1  59.2     4.7      M    M
 11000   -5.2  22.6   275   17    9  -5.4  -3.0   12.6  54.7     2.4      M    M
 10500   -6.0  21.2   285   13    7  -4.9  -2.7   10.2  50.3     0.1      M    M
 10250   -6.3  20.7   290   11    6  -1.3  -0.7    9.1  48.4    -0.8    328  1.7
 10000   -6.2  20.8   290   10    5   0.9   0.5    8.4  47.1    -1.6    320  1.6
  9750   -6.2  20.8   300    8    4   2.5   1.4    7.7  45.9    -2.2    309  1.6
  9500   -5.9  21.4   315    7    3   4.7   2.6    7.2  45.0    -2.7    294  1.5
  9250   -5.5  22.1   325    6    3   5.2   2.9    6.9  44.3    -3.0    275  1.4
  9000   -5.1  22.8   345    5    3   5.4   3.0    6.5  43.7    -3.4    256  1.3
  8750   -4.7  23.5   360    5    3   5.4   3.0    6.2  43.1    -3.7    237  1.2
  8500   -4.3  24.3   020    6    3   5.0   2.7    5.8  42.5    -4.1    218  1.1
  8250   -4.0  24.8   030    7    3   4.7   2.6    5.4  41.8    -4.5    200  1.0
  8000   -3.6  25.5   040    7    4   4.8   2.6    5.1  41.1    -4.9    182  0.9
  7750   -3.3  26.1   045    8    4   4.5   2.5    4.7  40.4    -5.3    165  0.8
  7500   -3.0  26.6   050    9    5   4.9   2.7    4.3  39.7    -5.7    147  0.7
  7250   -2.6  27.3   055   10    5   5.5   3.0    3.9  39.1    -6.0    128  0.7
  7000   -2.2  28.0   055   10    5   5.3   2.9    3.6  38.5    -6.4    109  0.6
  6750   -1.7  28.9   055   11    5   7.7   4.2    3.3  38.0    -6.7     88  0.4
  6500   -1.1  30.0   050   10    5   9.9   5.4    3.3  37.9    -6.8     61  0.3
  6250   -0.4  31.3   045    9    5   9.7   5.3    3.3  37.9    -6.8     33  0.2
  6000    0.3  32.5   040    9    5   9.9   5.4    3.3  37.9    -6.9      4  0.0
  5750    1.1  34.0   040    8    4  11.9   6.5    3.4  38.0    -6.9      M    M
  5500    2.1  35.8   040    8    4  15.1   8.3    3.6  38.6    -6.6      M    M

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

           09/12/2014 at 0900 MDT          |       09/12/2014 at 1200 MDT
                                           |
K index... -28.1  LI... +11.8              | K index... -30.6  LI... +9.7
CAPE... 0.0  CIN... -0.8                   | 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 -62.5 -80.5  280  54 28   1.4   0.8 | -62.8 -81.0  280  53 27   1.1   0.6
 45000 -59.6 -75.3  275  81 42   4.4   2.4 | -60.2 -76.4  280  79 41   4.5   2.5
 40000 -52.9 -63.2  280  83 43   4.3   2.4 | -53.1 -63.6  285  80 41   4.7   2.6
 38000 -50.4 -58.7  285  79 41   4.1   2.3 | -50.3 -58.5  285  76 39   4.7   2.6
 36000 -47.9 -54.2  285  74 38   4.1   2.3 | -47.5 -53.5  285  72 37   4.7   2.6
 34000 -44.4 -47.9  285  68 35   6.0   3.3 | -44.3 -47.7  285  66 34   5.7   3.1
 32000 -40.8 -41.4  285  62 32   6.0   3.3 | -40.9 -41.6  285  58 30   5.7   3.1
 30000 -36.5 -33.7  285  58 30   7.9   4.3 | -36.7 -34.1  285  53 27   8.0   4.4
 29000 -34.1 -29.4  285  56 29   7.9   4.3 | -34.3 -29.7  285  51 26   8.0   4.4
 28000 -31.8 -25.2  285  55 28   7.9   4.3 | -31.3 -24.3  290  49 25   8.0   4.4
 27000 -29.4 -20.9  285  54 28   7.8   4.3 | -29.0 -20.2  290  48 25   7.8   4.3
 26000 -27.1 -16.8  285  53 27   7.8   4.3 | -26.6 -15.9  290  47 24   7.8   4.3
 25000 -24.8 -12.6  285  52 27   7.8   4.3 | -24.3 -11.7  290  46 24   7.8   4.3
 24000 -22.4  -8.3  285  51 26   8.4   4.6 | -21.9  -7.4  290  46 24   8.2   4.5
 23000 -19.8  -3.6  285  50 26   8.4   4.6 | -19.4  -2.9  290  45 23   8.2   4.5
 22000 -17.3   0.9  285  49 25   8.4   4.6 | -17.0   1.4  295  44 23   8.4   4.6
 21000 -15.1   4.8  285  48 25   6.0   3.3 | -14.9   5.2  295  43 22   6.1   3.3
 20000 -13.3   8.1  290  47 24   6.0   3.3 | -13.1   8.4  295  42 21   6.1   3.3
 19500 -12.4   9.7  290  46 24   6.0   3.3 | -12.2  10.0  295  41 21   6.1   3.3
 19000 -11.5  11.3  290  46 23   6.0   3.3 | -11.3  11.7  295  40 21   6.3   3.5
 18500 -10.6  12.9  290  45 23   6.1   3.4 | -10.3  13.5  295  40 20   6.5   3.5
 18000  -9.2  15.4  290  45 23   6.6   3.6 |  -9.3  15.3  295  39 20   6.3   3.5
 17500  -8.1  17.4  290  45 23   8.0   4.4 |  -8.3  17.1  295  39 20   8.1   4.5
 17000  -6.9  19.6  290  45 23   8.1   4.5 |  -7.1  19.2  295  39 20   8.0   4.4
 16500  -5.8  21.6  290  44 23   6.3   3.5 |  -5.9  21.4  295  39 20   7.1   3.9
 16000  -4.8  23.4  290  44 23   6.3   3.4 |  -4.9  23.2  295  38 20   6.5   3.6
 15500  -3.9  25.0  290  43 22   5.1   2.8 |  -3.9  25.0  295  38 20   6.3   3.4
 15000  -3.3  26.1  285  42 21   4.3   2.4 |  -3.1  26.4  295  38 19   5.2   2.8
 14500  -2.7  27.1  285  40 21   3.7   2.1 |  -2.4  27.7  295  37 19   5.4   3.0
 14000  -2.4  27.7  280  38 20   2.1   1.1 |  -1.5  29.3  295  35 18   3.6   2.0
 13500  -2.1  28.2  280  36 18   2.0   1.1 |  -1.0  30.2  290  34 17   2.7   1.5
 13000  -2.3  27.9  280  33 17  -2.2  -1.2 |  -0.9  30.4  290  31 16   0.4   0.2
 12500  -2.6  27.3  275  29 15  -1.8  -1.0 |  -0.9  30.4  290  28 15  -0.1  -0.0
 12000  -3.3  26.1  275  25 13  -6.2  -3.4 |  -1.4  29.5  285  24 13  -4.0  -2.2
 11500  -4.2  24.4  280  20 10  -5.8  -3.2 |  -2.1  28.2  285  20 10  -4.5  -2.5
 11000  -5.1  22.8  280  16  8  -5.7  -3.1 |  -3.2  26.2  285  15  8  -8.8  -4.8
 10500  -6.0  21.2  285  11  6  -5.2  -2.8 |  -4.5  23.9  280  10  5  -6.0  -3.3
 10250  -6.3  20.7  285   9  5  -3.0  -1.7 |  -4.7  23.5  275   8  4  -0.0  -0.0
 10000  -6.5  20.3  285   8  4  -1.7  -0.9 |  -4.7  23.5  270   7  4   1.3   0.7
  9750  -6.5  20.3  290   7  3   0.5   0.3 |  -4.6  23.7  260   5  3   1.0   0.6
  9500  -6.3  20.7  300   4  2   4.9   2.7 |  -4.5  23.9  240   4  2   2.3   1.3
  9250  -5.9  21.4  310   3  2   7.2   4.0 |  -4.2  24.4  225   3  2   3.5   1.9
  9000  -5.3  22.5  330   3  1   8.3   4.5 |  -4.0  24.8  205   3  1   3.2   1.8
  8750  -4.8  23.4  350   3  1   4.9   2.7 |  -3.7  25.3  180   3  1   4.4   2.4
  8500  -4.5  23.9  020   3  1   3.6   2.0 |  -3.3  26.1  150   3  1   6.4   3.5
  8250  -4.1  24.6  035   3  2   6.0   3.3 |  -2.8  27.0  135   3  2   7.0   3.8
  8000  -3.7  25.3  045   4  2   5.1   2.8 |  -2.3  27.9  125   4  2   7.1   3.9
  7750  -3.3  26.1  050   5  2   6.1   3.3 |  -1.8  28.8  115   4  2   9.8   5.4
  7500  -2.9  26.8  065   5  3   6.1   3.3 |  -1.0  30.2  115   5  2  10.6   5.8
  7250  -2.5  27.5  070   6  3   5.2   2.8 |  -0.2  31.6  115   4  2   9.6   5.3
  7000  -2.1  28.2  080   7  3   5.8   3.2 |   0.5  32.9  115   4  2   9.9   5.5
  6750  -1.6  29.1  080   7  3   8.0   4.4 |   1.2  34.2  110   4  2  10.3   5.7
  6500  -1.0  30.2  070   6  3   9.4   5.1 |   2.0  35.6  110   4  2  10.5   5.7
  6250  -0.3  31.5  060   6  3   9.3   5.1 |   2.8  37.0  110   4  2  10.7   5.9
  6000   0.4  32.7  055   5  3   9.9   5.5 |   3.6  38.5  110   4  2  10.0   5.5
  5750   1.2  34.2  050   5  3  13.1   7.2 |   4.4  39.9  110   4  2  15.7   8.6
  5500   2.4  36.3  050   5  3  17.5   9.6 |   6.1  43.0  110   4  2  27.5  15.1

           09/12/2014 at 1500 MDT          |       09/12/2014 at 1800 MDT
                                           |
K index... -23.1  LI... +7.8               | K index... -15.4  LI... +6.7
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 -63.2 -81.8  280  53 27   1.4   0.8 | -64.0 -83.2  280  52 27   2.0   1.1
 45000 -60.3 -76.5  280  78 40   4.3   2.3 | -60.4 -76.7  285  74 38   4.2   2.3
 40000 -53.6 -64.5  280  77 40   5.2   2.9 | -53.7 -64.7  285  73 37   5.7   3.1
 38000 -50.3 -58.5  280  74 38   5.4   3.0 | -50.2 -58.4  285  68 35   5.8   3.2
 36000 -47.1 -52.8  285  70 36   5.4   3.0 | -46.7 -52.1  290  64 33   5.8   3.2
 34000 -43.8 -46.8  285  65 33   5.4   3.0 | -43.1 -45.6  290  60 31   6.0   3.3
 32000 -40.5 -40.9  285  58 30   5.4   3.0 | -39.5 -39.1  290  57 29   6.0   3.3
 30000 -36.5 -33.7  285  53 27   7.6   4.2 | -35.6 -32.1  295  54 28   6.9   3.8
 29000 -34.3 -29.7  285  51 26   7.6   4.2 | -33.0 -27.4  295  52 27   6.9   3.8
 28000 -31.4 -24.5  285  48 25   7.6   4.2 | -31.0 -23.8  295  50 26   6.9   3.8
 27000 -29.2 -20.6  290  47 24   7.5   4.1 | -28.8 -19.8  295  48 25   7.3   4.0
 26000 -27.0 -16.6  290  45 23   7.5   4.1 | -26.6 -15.9  295  45 23   7.3   4.0
 25000 -24.7 -12.5  290  43 22   7.5   4.1 | -24.4 -11.9  295  42 22   7.3   4.0
 24000 -22.3  -8.1  290  42 22   8.3   4.5 | -22.0  -7.6  295  40 21   8.4   4.6
 23000 -19.8  -3.6  290  41 21   8.3   4.6 | -19.5  -3.1  295  38 20   8.4   4.6
 22000 -17.3   0.9  295  40 21   8.5   4.7 | -17.0   1.4  295  36 19   8.6   4.7
 21000 -15.2   4.6  295  38 20   6.4   3.5 | -14.8   5.4  295  35 18   6.7   3.7
 20000 -13.3   8.1  295  37 19   6.4   3.5 | -12.8   9.0  295  34 17   6.8   3.7
 19500 -12.3   9.9  295  36 19   6.4   3.5 | -11.8  10.8  295  33 17   6.8   3.7
 19000 -11.4  11.5  295  35 18   6.7   3.7 | -10.8  12.6  295  33 17   6.6   3.6
 18500 -10.3  13.5  300  35 18   6.8   3.7 |  -9.8  14.4  295  33 17   6.5   3.6
 18000  -9.3  15.3  300  35 18   6.8   3.7 |  -8.8  16.2  295  33 17   6.5   3.6
 17500  -8.2  17.2  300  34 18   8.0   4.4 |  -7.8  18.0  295  33 17   6.7   3.7
 17000  -7.0  19.4  295  35 18   7.9   4.3 |  -6.8  19.8  295  33 17   6.6   3.6
 16500  -5.9  21.4  295  35 18   7.5   4.1 |  -5.8  21.6  295  33 17   7.5   4.1
 16000  -4.8  23.4  295  35 18   7.4   4.0 |  -4.6  23.7  295  33 17   7.9   4.3
 15500  -3.6  25.5  295  36 18   7.2   3.9 |  -3.5  25.7  290  34 17   7.8   4.3
 15000  -2.6  27.3  295  36 18   6.6   3.6 |  -2.3  27.9  290  34 17   7.4   4.1
 14500  -1.2  29.8  290  36 18   6.0   3.3 |  -0.7  30.7  290  34 17   7.3   4.0
 14000  -0.4  31.3  290  34 18   5.7   3.1 |   0.3  32.5  290  33 17   7.3   4.0
 13500   0.4  32.7  290  33 17   4.6   2.5 |   1.4  34.5  290  31 16   6.4   3.5
 13000   0.7  33.3  290  30 15   2.1   1.1 |   2.0  35.6  290  28 15   4.2   2.3
 12500   0.9  33.6  290  26 14   1.4   0.8 |   2.6  36.7  290  25 13   3.4   1.8
 12000   0.7  33.3  290  22 11  -2.6  -1.4 |   2.6  36.7  290  21 11  -0.7  -0.4
 11500   0.3  32.5  290  18  9  -3.2  -1.7 |   2.5  36.5  295  17  9  -1.3  -0.7
 11000  -0.6  30.9  285  14  7  -6.7  -3.7 |   1.7  35.1  290  13  7  -6.2  -3.4
 10500  -1.7  28.9  280   9  5  -5.2  -2.9 |   0.8  33.4  280   9  5  -5.5  -3.0
 10250  -2.0  28.4  270   8  4  -2.6  -1.4 |   0.4  32.7  275   8  4  -4.3  -2.3
 10000  -2.1  28.2  265   7  3  -0.8  -0.4 |   0.1  32.2  265   7  4  -3.7  -2.0
  9750  -2.1  28.2  240   4  2  -0.5  -0.3 |  -0.3  31.5  220   5  2  -5.2  -2.9
  9500  -2.1  28.2  195   4  2   2.2   1.2 |  -0.6  30.9  170   6  3   0.0   0.0
  9250  -1.8  28.8  170   4  2   4.9   2.7 |  -0.3  31.5  160   7  4   6.3   3.5
  9000  -1.5  29.3  150   5  2   5.6   3.1 |   0.2  32.4  155   8  4   7.4   4.1
  8750  -1.0  30.2  140   5  3   8.8   4.8 |   0.8  33.4  150   8  4  10.2   5.6
  8500  -0.3  31.5  135   6  3   9.8   5.4 |   1.6  34.9  150   8  4   9.9   5.4
  8250   0.4  32.7  135   6  3   9.2   5.1 |   2.3  36.1  150   8  4   8.8   4.8
  8000   1.1  34.0  135   6  3   9.8   5.4 |   3.0  37.4  150   8  4   9.7   5.3
  7750   1.9  35.4  135   6  3  10.6   5.8 |   3.7  38.7  150   8  4  11.1   6.1
  7500   2.7  36.9  135   6  3  10.4   5.7 |   4.6  40.3  145   8  4  10.4   5.7
  7250   3.5  38.3  135   6  3  10.0   5.5 |   5.3  41.5  145   8  4  10.0   5.5
  7000   4.2  39.6  135   6  3  10.0   5.5 |   6.0  42.8  145   8  4   8.8   4.8
  6750   4.9  40.8  135   5  3  10.1   5.5 |   6.6  43.9  145   7  4   9.0   4.9
  6500   5.7  42.3  135   5  3  10.3   5.6 |   7.4  45.3  145   7  4  10.7   5.9
  6250   6.5  43.7  135   5  3  10.2   5.6 |   8.2  46.8  145   7  4  10.3   5.7
  6000   7.2  45.0  130   5  3  10.3   5.6 |   9.0  48.2  145   7  4  10.1   5.6
  5750   8.2  46.8  135   5  2  16.3   9.0 |   9.7  49.5  145   7  4  12.1   6.6
  5500   9.7  49.5  130   5  3  26.2  14.4 |  10.8  51.4  145   7  3  16.4   9.0
________________________________________________________________________________

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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