Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 280014
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1814 MDT Monday, April 27, 2015

This forecast is for Tuesday, April 28, 2015:

If the trigger temperature of 49.7 F/9.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 462 ft/min (2.3 m/s)
   Maximum height of thermals.................. 12320 ft MSL (7013 ft AGL)

Forecast maximum temperature................... 61.0 F/16.6 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11303 ft MSL (5997 ft AGL)
Thermal soaring outlook for Wednesday 04/29.... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 11959 ft MSL (6652 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 12451 ft MSL (7144 ft AGL)
Wave soaring outlook for Wednesday 04/29....... Poor

Remarks... None

Sunrise/Sunset.................... 06:04:08 / 19:49:36 MDT
Total possible sunshine........... 13 hr 45 min 28 sec (825 min 28 sec)
Altitude of sun at 12:57:03 MDT... 64.46 degrees

Upper air data from numerical model forecast valid on 04/28/2015 at 0600 MDT

Freezing level.................. 8292 ft MSL (2985 ft AGL)
Convective condensation level... 13800 ft MSL (8493 ft AGL)
Lifted condensation level....... 12890 ft MSL (7584 ft AGL)
Lifted index.................... +1.3
K index......................... -0.2

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  -59.3 -74.7   005   39   20   2.6   1.4      M     M       M      M    M
 45000  -55.6 -68.1   010   46   24   0.8   0.4      M     M       M      M    M
 40000  -54.1 -65.4   020   55   28   1.0   0.5      M     M       M      M    M
 38000  -53.3 -63.9   020   56   29   1.6   0.9      M     M       M      M    M
 36000  -52.4 -62.3   025   54   28   1.6   0.9      M     M       M      M    M
 34000  -50.6 -59.1   025   51   26   5.1   2.8      M     M       M      M    M
 32000  -47.5 -53.5   025   44   23   5.2   2.8      M     M       M      M    M
 30000  -43.9 -47.0   030   39   20   7.7   4.2   32.2  89.9    12.1      M    M
 29000  -41.6 -42.9   030   38   19   7.8   4.3   31.3  88.4    11.6      M    M
 28000  -39.3 -38.7   030   37   19   7.8   4.3   30.6  87.1    11.2      M    M
 27000  -37.0 -34.6   035   36   18   7.2   3.9   29.9  85.8    10.7      M    M
 26000  -34.8 -30.6   030   31   16   7.1   3.9   28.8  83.8    10.0      M    M
 25000  -32.7 -26.9   030   26   14   7.1   3.9   27.8  82.0     9.3      M    M
 24000  -30.5 -22.9   030   22   11   7.0   3.9   26.9  80.5     8.7      M    M
 23000  -28.4 -19.1   020   18    9   7.0   3.8   25.8  78.5     7.9      M    M
 22000  -26.4 -15.5   015   14    7   7.1   3.9   24.8  76.7     7.2      M    M
 21000  -24.2 -11.6   005   11    6   7.9   4.3   24.0  75.2     6.5      M    M
 20000  -21.9  -7.4   015    9    5   7.8   4.3   23.3  73.9     6.0      M    M
 19500  -20.7  -5.3   020    8    4   7.8   4.3   22.9  73.3     5.7      M    M
 19000  -19.5  -3.1   025    8    4   7.9   4.3   22.6  72.7     5.5      M    M
 18500  -18.4  -1.1   030    7    3   7.2   4.0   22.3  72.1     5.2      M    M
 18000  -17.3   0.9   040    4    2   7.3   4.0   21.8  71.3     4.9      M    M
 17500  -15.6   3.9   070    2    1   8.4   4.6   21.3  70.3     4.4      M    M
 17000  -14.3   6.3   070    2    1   8.4   4.6   21.0  69.9     4.2      M    M
 16500  -13.1   8.4   070    2    1   7.9   4.3   20.8  69.4     4.1      M    M
 16000  -11.9  10.6   055    3    2   7.6   4.2   20.4  68.8     3.7      M    M
 15500  -10.8  12.6   045    4    2   7.8   4.3   20.1  68.1     3.4      M    M
 15000   -9.6  14.7   045    4    2   8.3   4.5   19.8  67.6     3.2      M    M
 14500   -8.3  17.1   050    5    3   8.2   4.5   19.6  67.2     3.0      M    M
 14000   -7.2  19.0   050    6    3   6.5   3.5   19.1  66.4     2.7      M    M
 13500   -6.2  20.8   055    6    3   7.1   3.9   18.6  65.5     2.3      M    M
 13000   -5.6  21.9   055    7    4   1.9   1.0   17.7  63.9     1.4      M    M
 12500   -5.2  22.6   050    8    4   2.9   1.6   16.6  61.8     0.3      M    M
 12000   -5.1  22.8   045    8    4   0.0   0.0   15.2  59.4    -1.0    449  2.3
 11500   -5.1  22.8   040    8    4   0.0   0.0   13.7  56.7    -2.5    435  2.2
 11000   -4.8  23.4   045    6    3   4.4   2.4   12.5  54.5    -3.7    412  2.1
 10500   -4.3  24.3   055    3    2   4.0   2.2   11.6  52.9    -4.6    380  1.9
 10250   -4.0  24.8   075    2    1   4.0   2.2   11.1  52.1    -5.1    364  1.8
 10000   -3.6  25.5   100    2    1   5.8   3.2   10.7  51.3    -5.5    347  1.8
  9750   -3.1  26.4   135    2    1   8.3   4.5   10.5  51.0    -5.7    324  1.6
  9500   -2.5  27.5   160    3    1   8.3   4.6   10.4  50.8    -5.9    298  1.5
  9250   -1.9  28.6   170    3    2   7.3   4.0   10.3  50.5    -6.0    273  1.4
  9000   -1.4  29.5   170    3    2   6.9   3.8   10.1  50.1    -6.3    251  1.3
  8750   -0.9  30.4   175    3    2   8.7   4.8    9.9  49.8    -6.5    227  1.2
  8500   -0.3  31.5   175    3    2   6.7   3.7    9.8  49.7    -6.6    201  1.0
  8250    0.0  32.0   180    3    2   3.6   2.0    9.4  48.9    -7.1    185  0.9
  8000    0.3  32.5   185    2    1   3.7   2.0    8.9  48.1    -7.6    170  0.9
  7750    0.5  32.9   200    2    1   5.6   3.1    8.5  47.3    -8.1    155  0.8
  7500    1.1  34.0   220    2    1   8.5   4.7    8.3  47.0    -8.3    132  0.7
  7250    1.7  35.1   235    2    1   8.6   4.7    8.2  46.8    -8.4    106  0.5
  7000    2.3  36.1   245    2    1   8.8   4.8    8.1  46.7    -8.6     80  0.4
  6750    2.9  37.2   255    2    1   8.2   4.5    8.1  46.5    -8.7     53  0.3
  6500    3.5  38.3   260    3    1   8.2   4.5    7.9  46.3    -8.9     28  0.1
  6250    4.2  39.6   260    3    2  10.0   5.5    7.9  46.2    -8.9      1  0.0
  6000    4.9  40.8   265    4    2   6.5   3.6    7.8  46.1    -9.0      M    M
  5750    4.9  40.8   265    4    2  -7.5  -4.1    7.1  44.9    -9.7      M    M
  5500    3.7  38.7   250    3    2 -21.2 -11.6    5.3  41.5   -11.7      M    M

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

           04/28/2015 at 0900 MDT          |       04/28/2015 at 1200 MDT
                                           |
K index... -3.8  LI... +277.8              | K index... -5.9  LI... +277.8
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.8
                                           |
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 -59.1 -74.4  005  38 20   3.2   1.8 | -59.3 -74.7  005  35 18   3.5   1.9
 45000 -54.5 -66.1  010  45 23  -0.7  -0.4 | -54.6 -66.3  010  41 21  -1.5  -0.8
 40000 -55.1 -67.2  020  52 27  -0.4  -0.2 | -56.3 -69.3  020  48 25  -1.0  -0.5
 38000 -54.1 -65.4  025  58 30   3.0   1.7 | -54.8 -66.6  025  57 29   3.9   2.1
 36000 -52.1 -61.8  030  68 35   3.0   1.7 | -52.5 -62.5  035  69 36   3.9   2.1
 34000 -49.9 -57.8  035  69 35   4.8   2.6 | -49.9 -57.8  035  74 38   5.6   3.1
 32000 -47.0 -52.6  035  56 29   4.8   2.6 | -46.5 -51.7  035  62 32   5.7   3.1
 30000 -43.6 -46.5  030  46 23   7.0   3.9 | -42.9 -45.2  030  53 27   6.7   3.7
 29000 -41.5 -42.7  030  43 22   7.0   3.9 | -40.9 -41.6  030  51 26   6.7   3.7
 28000 -39.4 -38.9  030  40 21   7.0   3.9 | -38.4 -37.1  035  48 25   6.7   3.7
 27000 -37.2 -35.0  030  38 20   8.6   4.7 | -36.3 -33.3  035  45 23   7.8   4.3
 26000 -34.6 -30.3  035  38 20   8.6   4.7 | -34.0 -29.2  035  42 22   7.8   4.3
 25000 -32.0 -25.6  035  38 20   8.6   4.7 | -31.7 -25.1  030  39 20   7.8   4.3
 24000 -29.5 -21.1  040  38 20   7.5   4.1 | -29.2 -20.6  030  36 19   9.3   5.1
 23000 -27.3 -17.1  035  32 17   7.1   3.9 | -26.5 -15.7  035  35 18   9.2   5.0
 22000 -25.2 -13.4  035  27 14   7.1   3.9 | -23.8 -10.8  040  34 17   9.1   5.0
 21000 -23.2  -9.8  035  21 11   6.3   3.4 | -21.4  -6.5  045  31 16   6.1   3.4
 20000 -21.3  -6.3  030  16  8   6.4   3.5 | -19.5  -3.1  040  24 13   6.2   3.4
 19500 -20.3  -4.5  030  13  7   6.4   3.5 | -18.6  -1.5  040  21 11   6.2   3.4
 19000 -19.4  -2.9  030  11  6   6.4   3.5 | -17.7   0.1  040  18  9   6.2   3.4
 18500 -17.8  -0.0  025   7  4   7.5   4.1 | -16.8   1.8  035  15  8   6.2   3.4
 18000 -16.7   1.9  020   5  3   7.5   4.1 | -15.8   3.6  035  11  6   6.2   3.4
 17500 -15.5   4.1  020   4  2   7.9   4.3 | -14.9   5.2  025   8  4   6.5   3.6
 17000 -14.3   6.3  015   3  2   7.9   4.3 | -13.9   7.0  020   6  3   6.7   3.7
 16500 -13.1   8.4  015   3  1   7.7   4.2 | -12.9   8.8  360   4  2   6.8   3.7
 16000 -12.0  10.4  020   3  2   7.6   4.2 | -11.9  10.6  345   3  2   7.2   3.9
 15500 -10.8  12.6  020   3  2   7.8   4.3 | -10.8  12.6  335   3  2   7.1   3.9
 15000  -9.6  14.7  025   3  2   8.3   4.5 |  -9.1  15.6  325   3  2   7.8   4.3
 14500  -8.3  17.1  035   3  2   8.2   4.5 |  -7.9  17.8  325   3  2   7.7   4.2
 14000  -7.2  19.0  045   4  2   7.1   3.9 |  -6.8  19.8  315   3  1   7.3   4.0
 13500  -6.1  21.0  060   4  2   7.4   4.1 |  -5.6  21.9  305   3  1   7.2   4.0
 13000  -5.2  22.6  065   5  3   4.8   2.6 |  -4.7  23.5  300   2  1   5.2   2.8
 12500  -4.4  24.1  065   6  3   5.5   3.0 |  -4.0  24.8  310   1  0   5.4   2.9
 12000  -4.0  24.8  065   7  4   0.4   0.2 |  -3.4  25.9  120   1  0   2.9   1.6
 11500  -3.9  25.0  065   7  4   0.8   0.5 |  -2.9  26.8  125   3  2   3.3   1.8
 11000  -3.6  25.5  065   7  3   3.2   1.8 |  -2.5  27.5  130   5  2   3.8   2.1
 10500  -3.2  26.2  065   5  3   3.2   1.7 |  -1.9  28.6  130   6  3   3.8   2.1
 10250  -3.0  26.6  065   5  2   3.2   1.8 |  -1.7  28.9  135   6  3   3.2   1.8
 10000  -2.8  27.0  065   4  2   4.3   2.4 |  -1.4  29.5  135   6  3   4.3   2.4
  9750  -2.4  27.7  070   3  2   5.9   3.2 |  -1.0  30.2  140   6  3   5.7   3.1
  9500  -2.0  28.4  090   2  1   6.1   3.3 |  -0.7  30.7  150   5  3   5.5   3.0
  9250  -1.6  29.1  115   2  1   5.7   3.1 |  -0.3  31.5  155   5  3   5.5   3.0
  9000  -1.2  29.8  140   2  1   5.7   3.2 |   0.1  32.2  155   5  2   5.9   3.2
  8750  -0.7  30.7  165   2  1   7.8   4.3 |   0.5  32.9  160   4  2   6.6   3.6
  8500  -0.1  31.8  185   2  1   7.8   4.3 |   1.0  33.8  170   4  2   7.6   4.2
  8250   0.4  32.7  190   3  1   6.2   3.4 |   1.5  34.7  170   3  2   8.2   4.5
  8000   0.8  33.4  200   3  1   6.4   3.5 |   2.1  35.8  170   3  2   8.4   4.6
  7750   1.3  34.3  205   3  1   6.9   3.8 |   2.7  36.9  170   3  1  10.8   5.9
  7500   1.8  35.2  205   2  1   6.8   3.7 |   3.5  38.3  170   3  1  10.7   5.9
  7250   2.3  36.1  210   2  1   6.3   3.4 |   4.2  39.6  175   3  1   8.7   4.8
  7000   2.7  36.9  215   2  1   6.3   3.4 |   4.9  40.8  180   3  1  10.6   5.8
  6750   3.1  37.6  225   2  1   6.9   3.8 |   5.8  42.4  180   3  1  10.9   6.0
  6500   3.7  38.7  235   2  1   8.2   4.5 |   6.5  43.7  180   2  1   9.8   5.4
  6250   4.3  39.7  240   2  1   8.3   4.6 |   7.3  45.1  180   2  1   9.9   5.4
  6000   4.9  40.8  245   2  1   8.6   4.7 |   8.0  46.4  185   2  1  10.6   5.8
  5750   5.6  42.1  245   2  1  13.3   7.3 |   9.0  48.2  185   2  1  16.7   9.2
  5500   6.8  44.2  250   2  1  20.0  11.0 |  10.5  50.9  185   2  1  24.4  13.4

           04/28/2015 at 1500 MDT          |       04/28/2015 at 1800 MDT
                                           |
K index... -5.2  LI... +276.8              | K index... -6.0  LI... +276.1
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.3
                                           |
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 -59.2 -74.6  360  31 16   4.0   2.2 | -59.3 -74.7  355  32 17   3.5   1.9
 45000 -53.8 -64.8  360  37 19  -2.0  -1.1 | -54.4 -65.9  360  39 20  -1.2  -0.7
 40000 -56.1 -69.0  005  47 24  -1.4  -0.7 | -55.7 -68.3  005  46 24  -0.7  -0.4
 38000 -54.7 -66.5  015  56 29   4.1   2.2 | -54.5 -66.1  020  53 27   3.1   1.7
 36000 -52.2 -62.0  030  70 36   4.1   2.2 | -52.6 -62.7  030  64 33   3.1   1.7
 34000 -49.5 -57.1  035  77 40   5.5   3.0 | -50.3 -58.5  035  70 36   5.3   2.9
 32000 -46.3 -51.3  030  65 33   5.5   3.0 | -47.1 -52.8  035  64 33   5.3   2.9
 30000 -42.3 -44.1  025  54 28   6.6   3.6 | -42.8 -45.0  035  58 30   8.1   4.5
 29000 -40.3 -40.5  030  52 27   6.6   3.6 | -40.4 -40.7  040  57 29   8.1   4.5
 28000 -38.3 -36.9  030  50 26   6.6   3.6 | -37.9 -36.2  040  55 29   8.2   4.5
 27000 -36.1 -33.0  035  47 24   8.8   4.9 | -35.4 -31.7  045  55 28   9.2   5.1
 26000 -33.5 -28.3  035  44 23   8.8   4.8 | -32.6 -26.7  045  54 28   9.2   5.1
 25000 -30.8 -23.4  040  41 21   8.8   4.8 | -29.8 -21.6  045  54 28   9.2   5.1
 24000 -28.3 -18.9  040  38 20   8.2   4.5 | -27.2 -17.0  045  52 27   7.4   4.0
 23000 -25.8 -14.4  040  34 18   8.2   4.5 | -24.9 -12.8  045  44 23   7.6   4.2
 22000 -23.3  -9.9  035  31 16   8.2   4.5 | -22.7  -8.9  045  37 19   7.6   4.2
 21000 -21.0  -5.8  035  27 14   7.6   4.2 | -20.3  -4.5  040  30 16   8.3   4.6
 20000 -18.7  -1.7  035  23 12   7.6   4.2 | -17.8  -0.0  035  27 14   8.3   4.6
 19500 -17.6   0.3  035  22 11   7.6   4.2 | -16.6   2.1  030  25 13   8.3   4.6
 19000 -16.4   2.5  030  20 10   7.7   4.2 | -15.4   4.3  025  23 12   8.4   4.6
 18500 -15.4   4.3  030  18  9   5.5   3.0 | -14.3   6.3  020  21 11   5.7   3.1
 18000 -14.6   5.7  025  16  8   5.7   3.1 | -13.4   7.9  015  20 10   6.0   3.3
 17500 -13.7   7.3  015  14  7   5.9   3.2 | -12.5   9.5  010  19 10   6.2   3.4
 17000 -12.9   8.8  010  12  6   5.9   3.3 | -11.6  11.1  005  18  9   6.3   3.4
 16500 -12.0  10.4  355  10  5   6.1   3.3 | -10.6  12.9  360  17  9   6.2   3.4
 16000 -11.0  12.2  345  10  5   6.7   3.7 |  -9.8  14.4  355  16  8   5.3   2.9
 15500  -9.6  14.7  330  10  5   6.9   3.8 |  -8.6  16.5  345  16  8   6.2   3.4
 15000  -8.5  16.7  325  10  5   7.1   3.9 |  -7.6  18.3  340  16  8   7.3   4.0
 14500  -7.5  18.5  320  10  5   7.2   4.0 |  -6.5  20.3  335  16  8   7.4   4.1
 14000  -6.3  20.7  315  10  5   7.8   4.3 |  -5.5  22.1  330  15  8   7.4   4.0
 13500  -5.1  22.8  315   9  5   7.7   4.2 |  -4.4  24.1  330  14  7   7.4   4.1
 13000  -4.1  24.6  310   9  4   6.1   3.3 |  -3.4  25.9  325  12  6   6.5   3.5
 12500  -3.1  26.4  310   8  4   6.3   3.5 |  -2.3  27.9  325  10  5   6.8   3.8
 12000  -2.4  27.7  305   6  3   4.3   2.3 |  -1.6  29.1  320   8  4   3.3   1.8
 11500  -1.7  28.9  295   4  2   4.5   2.5 |  -1.0  30.2  305   5  2   3.6   2.0
 11000  -1.2  29.8  250   2  1   3.5   1.9 |  -0.4  31.3  250   2  1   4.7   2.6
 10500  -0.7  30.7  155   3  2   3.8   2.1 |   0.1  32.2  175   5  2   5.1   2.8
 10250  -0.5  31.1  150   4  2   1.4   0.8 |   0.4  32.7  170   6  3   2.5   1.3
 10000  -0.4  31.3  150   5  2   5.3   2.9 |   0.6  33.1  165   6  3   6.2   3.4
  9750   0.2  32.4  145   5  2  10.4   5.7 |   1.3  34.3  165   6  3  11.3   6.2
  9500   0.8  33.4  140   4  2   8.8   4.9 |   2.0  35.6  160   5  3   9.8   5.4
  9250   1.4  34.5  135   4  2   7.2   3.9 |   2.6  36.7  155   5  3   7.9   4.3
  9000   1.9  35.4  135   4  2   7.9   4.4 |   3.1  37.6  155   5  3   8.2   4.5
  8750   2.6  36.7  135   4  2  11.2   6.1 |   3.9  39.0  155   5  3  10.8   5.9
  8500   3.4  38.1  135   4  2  10.5   5.7 |   4.6  40.3  155   5  2  10.1   5.6
  8250   4.1  39.4  135   4  2   8.8   4.9 |   5.3  41.5  150   5  2   9.0   4.9
  8000   4.7  40.5  130   4  2   9.3   5.1 |   5.9  42.6  150   4  2   9.0   4.9
  7750   5.4  41.7  130   4  2  10.8   5.9 |   6.6  43.9  150   4  2   9.2   5.0
  7500   6.2  43.2  135   4  2  10.6   5.8 |   7.3  45.1  150   4  2   9.8   5.4
  7250   7.0  44.6  135   4  2   9.7   5.3 |   8.0  46.4  150   4  2  10.2   5.6
  7000   7.7  45.9  130   4  2   9.9   5.4 |   8.8  47.8  150   4  2  10.1   5.6
  6750   8.5  47.3  135   3  2  10.0   5.5 |   9.5  49.1  150   4  2  10.0   5.5
  6500   9.2  48.6  135   3  2  10.3   5.7 |  10.3  50.5  155   3  2   9.9   5.4
  6250  10.0  50.0  135   3  2  10.4   5.7 |  11.0  51.8  155   3  2   9.6   5.3
  6000  10.8  51.4  135   3  2  10.2   5.6 |  11.7  53.1  155   3  2  10.5   5.8
  5750  11.6  52.9  135   3  1  15.2   8.4 |  12.5  54.5  155   3  1  12.1   6.6
  5500  13.0  55.4  130   3  1  24.2  13.3 |  13.4  56.1  150   3  1  12.0   6.6
________________________________________________________________________________

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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