Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 210033
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1732 MST Saturday, December 20, 2014

This forecast is for Sunday, December 21, 2014:

If the trigger temperature of 51.1 F/10.6 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 262 ft/min (1.3 m/s)
   Maximum height of thermals.................. 10512 ft MSL (5225 ft AGL)

Forecast maximum temperature................... 55.0 F/13.2 C
Time of trigger temperature.................... 1200 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8888 ft MSL (3601 ft AGL)
Thermal soaring outlook for Monday 12/22....... 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....................... 29864 ft MSL (24577 ft AGL)
Wave soaring outlook for Monday 12/22.......... Good

Remarks...

Sunrise/Sunset.................... 07:17:01 / 16:38:25 MST
Total possible sunshine........... 9 hr 21 min 25 sec (561 min 25 sec)
Altitude of sun at 11:57:43 MST... 26.86 degrees

Upper air data from numerical model forecast valid on 12/21/2014 at 0500 MST

Freezing level.................. 5406 ft MSL (119 ft AGL)
Additional freezing level....... 7719 ft MSL (2432 ft AGL)
Convective condensation level... 15329 ft MSL (10042 ft AGL)
Lifted condensation level....... 13920 ft MSL (8633 ft AGL)
Lifted index.................... +3.8
K index......................... +6.3

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  -57.5 -71.5   325   26   13  -0.2  -0.1      M     M       M      M    M
 45000  -57.7 -71.9   330   34   18  -0.1  -0.1      M     M       M      M    M
 40000  -56.3 -69.3   330   51   26   1.0   0.6      M     M       M      M    M
 38000  -55.7 -68.3   330   58   30   0.9   0.5      M     M       M      M    M
 36000  -55.2 -67.4   340   66   34   0.9   0.5      M     M       M      M    M
 34000  -54.7 -66.5   350   76   39   1.7   0.9      M     M       M      M    M
 32000  -51.4 -60.5   350   91   47   5.9   3.2      M     M       M      M    M
 30000  -47.8 -54.0   350  106   54   6.5   3.6      M     M       M      M    M
 29000  -45.1 -49.2   350   89   46   7.4   4.1   27.1  80.8    10.9      M    M
 28000  -42.9 -45.2   345   75   39   7.4   4.1   26.2  79.1    10.3      M    M
 27000  -40.7 -41.3   340   61   31   7.3   4.0   25.4  77.7     9.8      M    M
 26000  -38.3 -36.9   340   52   27   8.0   4.4   24.6  76.3     9.3      M    M
 25000  -35.9 -32.6   335   46   23   8.0   4.4   23.9  75.1     8.9      M    M
 24000  -33.5 -28.3   330   39   20   7.9   4.4   23.3  74.0     8.5      M    M
 23000  -30.9 -23.6   325   35   18   9.1   5.0   22.9  73.3     8.3      M    M
 22000  -28.2 -18.8   320   33   17   9.2   5.0   22.7  72.9     8.2      M    M
 21000  -25.5 -13.9   310   32   16   9.1   5.0   22.6  72.6     8.2      M    M
 20000  -23.1  -9.6   310   30   15   7.7   4.2   21.9  71.3     7.6      M    M
 19500  -22.0  -7.6   310   28   15   7.7   4.2   21.5  70.7     7.4      M    M
 19000  -20.8  -5.4   310   27   14   7.7   4.2   21.1  70.0     7.1      M    M
 18500  -19.7  -3.5   305   26   13   7.9   4.3   20.8  69.5     6.8      M    M
 18000  -18.6  -1.5   310   25   13   6.0   3.3   20.3  68.6     6.5      M    M
 17500  -17.7   0.1   310   24   13   6.2   3.4   19.7  67.5     6.0      M    M
 17000  -16.8   1.8   310   24   12   6.3   3.4   19.1  66.4     5.5      M    M
 16500  -15.9   3.4   315   23   12   6.3   3.5   18.5  65.4     5.0      M    M
 16000  -14.9   5.2   315   23   12   6.3   3.4   18.0  64.4     4.5      M    M
 15500  -14.1   6.6   315   22   11   5.6   3.1   17.3  63.2     3.9      M    M
 15000  -13.2   8.2   315   20   10   5.7   3.1   16.6  61.9     3.3      M    M
 14500  -12.0  10.4   320   18    9   5.5   3.0   15.6  60.1     2.4      M    M
 14000  -11.2  11.8   320   17    9   5.9   3.2   14.9  58.8     1.7      M    M
 13500  -10.1  13.8   320   15    8   7.3   4.0   14.4  58.0     1.3      M    M
 13000   -9.1  15.6   320   14    7   7.4   4.0   14.0  57.2     0.9      M    M
 12500   -7.9  17.8   320   13    7   8.7   4.8   13.8  56.8     0.7      M    M
 12000   -6.6  20.1   320   13    7   8.7   4.8   13.6  56.4     0.5      M    M
 11500   -5.2  22.6   315   14    7   9.6   5.3   13.5  56.3     0.4      M    M
 11000   -3.8  25.2   315   16    8   9.2   5.0   13.4  56.2     0.4      M    M
 10500   -2.8  27.0   310   20   10   5.3   2.9   13.0  55.4    -0.1    357  1.8
 10250   -2.4  27.7   310   22   11   5.9   3.2   12.7  54.8    -0.4    337  1.7
 10000   -2.0  28.4   305   24   12   5.3   2.9   12.4  54.2    -0.7    317  1.6
  9750   -1.6  29.1   300   26   13   3.2   1.8   11.9  53.5    -1.1    300  1.5
  9500   -1.5  29.3   300   26   13   2.2   1.2   11.3  52.4    -1.7    288  1.5
  9250   -1.3  29.7   295   27   14   2.4   1.3   10.8  51.4    -2.3    275  1.4
  9000   -1.1  30.0   295   27   14   2.7   1.5   10.2  50.4    -2.8    263  1.3
  8750   -0.9  30.4   290   26   13   2.4   1.3    9.7  49.4    -3.4    249  1.3
  8500   -0.8  30.6   285   24   13   1.8   1.0    9.1  48.3    -4.0    238  1.2
  8250   -0.7  30.7   280   23   12   1.8   1.0    8.4  47.2    -4.6    227  1.2
  8000   -0.5  31.1   275   21   11   4.5   2.5    7.9  46.2    -5.1    214  1.1
  7750   -0.0  32.0   270   18    9   6.3   3.4    7.6  45.7    -5.4    193  1.0
  7500    0.3  32.5   265   16    8   4.8   2.7    7.3  45.1    -5.8    174  0.9
  7250    0.7  33.3   255   14    7   6.5   3.6    6.9  44.5    -6.1    155  0.8
  7000    1.3  34.3   250   13    6   9.1   5.0    6.8  44.3    -6.3    130  0.7
  6750    2.0  35.6   245   11    6   8.6   4.7    6.8  44.2    -6.4    102  0.5
  6500    2.6  36.7   235   10    5   7.5   4.1    6.6  43.9    -6.5     78  0.4
  6250    3.0  37.4   230   10    5   2.2   1.2    6.3  43.4    -6.9     58  0.3
  6000    2.9  37.2   220   10    5  -0.8  -0.5    5.5  42.0    -7.7     52  0.3
  5750    2.8  37.0   210   10    5  -6.3  -3.5    4.7  40.4    -8.6     49  0.3
  5500    1.5  34.7   205   13    7 -29.3 -16.1    2.7  36.8   -10.6     80  0.4

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

           12/21/2014 at 0800 MST          |       12/21/2014 at 1100 MST
                                           |
K index... +11.3  LI... +3.2               | K index... +16.9  LI... +1.9
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 -57.9 -72.2  330  21 11   0.6   0.3 | -57.4 -71.3  335  15  8   0.1   0.1
 45000 -57.1 -70.8  325  24 12   0.6   0.3 | -57.2 -71.0  305  13  6   0.1   0.0
 40000 -56.5 -69.7  330  47 24   0.4   0.2 | -56.1 -69.0  330  40 20   0.8   0.4
 38000 -56.1 -69.0  335  59 30   1.0   0.6 | -55.6 -68.1  335  53 27   0.8   0.4
 36000 -55.5 -67.9  340  74 38   1.0   0.6 | -55.1 -67.2  335  70 36   0.8   0.4
 34000 -54.9 -66.8  340  90 46   2.2   1.2 | -54.7 -66.5  335  87 45   2.1   1.2
 32000 -51.4 -60.5  340  92 47   6.1   3.4 | -50.9 -59.6  335  84 43   5.8   3.2
 30000 -47.0 -52.6  335  92 47   9.4   5.2 | -47.1 -52.8  335  81 42  10.1   5.6
 29000 -44.3 -47.7  335  87 45   9.1   5.0 | -44.2 -47.6  335  82 42   9.7   5.3
 28000 -41.6 -42.9  335  81 42   9.1   5.0 | -41.3 -42.3  335  83 43   9.7   5.3
 27000 -38.9 -38.0  335  76 39   9.3   5.1 | -38.3 -36.9  335  84 43   9.9   5.4
 26000 -36.6 -33.9  335  69 35   7.3   4.0 | -35.8 -32.4  335  80 41   8.1   4.4
 25000 -34.4 -29.9  330  61 31   7.3   4.0 | -33.4 -28.1  335  75 39   8.1   4.5
 24000 -32.2 -26.0  330  53 27   7.3   4.0 | -31.0 -23.8  335  71 36   8.2   4.5
 23000 -30.0 -22.0  325  46 24   7.4   4.1 | -28.7 -19.7  335  63 32   7.5   4.1
 22000 -27.8 -18.0  320  40 21   7.4   4.1 | -26.4 -15.5  330  54 28   7.5   4.1
 21000 -25.6 -14.1  310  34 18   7.4   4.1 | -24.2 -11.6  325  44 23   7.5   4.1
 20000 -23.4 -10.1  310  30 15   7.6   4.1 | -22.1  -7.8  325  38 19   6.8   3.8
 19500 -22.2  -8.0  305  28 14   7.6   4.1 | -21.1  -6.0  325  35 18   6.9   3.8
 19000 -21.1  -6.0  305  26 14   7.6   4.1 | -20.1  -4.2  325  32 16   6.9   3.8
 18500 -20.0  -4.0  300  24 13   7.6   4.2 | -19.1  -2.4  325  29 15   6.9   3.8
 18000 -18.9  -2.0  300  23 12   7.1   3.9 | -18.1  -0.6  320  26 13   6.5   3.6
 17500 -17.8  -0.0  300  22 11   7.1   3.9 | -17.1   1.2  320  24 13   6.5   3.6
 17000 -16.8   1.8  295  20 11   6.5   3.6 | -16.2   2.8  320  23 12   6.9   3.8
 16500 -15.9   3.4  295  19 10   6.1   3.3 | -15.1   4.8  325  21 11   7.1   3.9
 16000 -15.0   5.0  290  18  9   6.2   3.4 | -13.5   7.7  325  19 10   7.4   4.1
 15500 -14.0   6.8  285  16  8   6.9   3.8 | -12.4   9.7  325  19 10   7.5   4.1
 15000 -12.5   9.5  285  14  7   7.4   4.0 | -11.3  11.7  330  18  9   8.4   4.6
 14500 -11.3  11.7  285  13  7   7.9   4.3 |  -9.9  14.2  330  18  9   9.7   5.3
 14000 -10.2  13.6  280  11  6   8.1   4.4 |  -8.4  16.9  330  18  9   9.6   5.3
 13500  -8.9  16.0  285  11  6   8.7   4.8 |  -7.0  19.4  330  18  9   9.2   5.0
 13000  -7.6  18.3  295  10  5   8.7   4.8 |  -5.7  21.7  330  19 10   9.2   5.0
 12500  -6.3  20.7  305  12  6   9.1   5.0 |  -4.4  24.1  330  21 11   8.3   4.5
 12000  -4.9  23.2  315  14  7   9.0   4.9 |  -3.1  26.4  325  23 12   8.5   4.7
 11500  -3.8  25.2  315  18  9   7.2   4.0 |  -2.1  28.2  325  26 13   5.1   2.8
 11000  -2.7  27.1  315  23 12   7.1   3.9 |  -1.3  29.7  315  28 15   5.6   3.0
 10500  -1.9  28.6  315  27 14   3.7   2.0 |  -0.6  30.9  315  31 16   3.6   2.0
 10250  -1.6  29.1  310  29 15   4.1   2.2 |  -0.4  31.3  310  32 16   3.8   2.1
 10000  -1.3  29.7  310  31 16   4.4   2.4 |  -0.1  31.8  310  33 17   3.9   2.2
  9750  -1.0  30.2  305  32 16   2.6   1.4 |   0.2  32.4  305  34 18   2.7   1.5
  9500  -0.9  30.4  305  32 17   0.9   0.5 |   0.3  32.5  300  34 17   1.7   1.0
  9250  -0.9  30.4  300  32 17   1.6   0.9 |   0.5  32.9  300  33 17   1.8   1.0
  9000  -0.8  30.6  300  33 17   0.5   0.3 |   0.6  33.1  295  33 17   2.4   1.3
  8750  -0.8  30.6  300  31 16   0.5   0.3 |   0.8  33.4  295  32 16   2.4   1.3
  8500  -0.7  30.7  295  28 14   1.5   0.8 |   0.9  33.6  290  29 15   1.8   1.0
  8250  -0.6  30.9  295  26 13   1.0   0.5 |   1.1  34.0  290  27 14   1.6   0.9
  8000  -0.5  31.1  290  23 12   3.3   1.8 |   1.2  34.2  285  24 13   3.0   1.7
  7750  -0.1  31.8  290  18  9   4.7   2.6 |   1.5  34.7  280  20 10   4.1   2.2
  7500   0.2  32.4  285  15  8   3.4   1.9 |   1.8  35.2  275  17  9   3.3   1.8
  7250   0.5  32.9  280  12  6   5.0   2.7 |   2.0  35.6  265  14  7   3.7   2.0
  7000   0.9  33.6  275  10  5   7.7   4.2 |   2.4  36.3  255  12  6   4.6   2.5
  6750   1.5  34.7  260   8  4   7.4   4.1 |   2.7  36.9  240  11  6   5.4   3.0
  6500   2.0  35.6  250   7  4   6.7   3.7 |   3.2  37.8  225  11  6   6.3   3.4
  6250   2.4  36.3  235   7  4   0.6   0.3 |   3.6  38.5  215  12  6   3.5   1.9
  6000   2.2  36.0  225   8  4  -3.0  -1.7 |   3.7  38.7  205  12  6   0.9   0.5
  5750   1.9  35.4  215   9  5  -8.6  -4.7 |   3.7  38.7  200  12  6  -1.0  -0.6
  5500   0.5  32.9  205  11  6 -28.2 -15.5 |   3.4  38.1  195   9  5  -4.2  -2.3

           12/21/2014 at 1400 MST          |       12/21/2014 at 1700 MST
                                           |
K index... +14.6  LI... +3.0               | K index... +15.5  LI... +2.7
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... -0.2
                                           |
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 -56.8 -70.2  325  15  8   0.2   0.1 | -57.0 -70.6  330  15  8   1.4   0.7
 45000 -56.6 -69.9  305  13  7   0.2   0.1 | -54.9 -66.8  305  16  8   1.7   0.9
 40000 -56.6 -69.9  320  41 21  -0.0  -0.0 | -57.3 -71.1  305  40 21  -1.7  -1.0
 38000 -56.6 -69.9  320  52 27   0.2   0.1 | -57.7 -71.9  315  51 26   1.4   0.8
 36000 -56.4 -69.5  325  62 32   0.2   0.1 | -56.8 -70.2  325  65 34   1.4   0.8
 34000 -55.9 -68.6  330  72 37   6.5   3.6 | -55.5 -67.9  335  83 43   7.4   4.1
 32000 -51.7 -61.1  325  64 33   7.0   3.8 | -50.9 -59.6  330  81 42   7.7   4.2
 30000 -47.3 -53.1  315  58 30  10.3   5.6 | -46.2 -51.2  330  79 40   8.5   4.7
 29000 -44.3 -47.7  315  58 30  10.0   5.5 | -43.7 -46.7  325  72 37   8.5   4.7
 28000 -41.3 -42.3  315  57 29  10.0   5.5 | -41.1 -42.0  325  66 34   8.5   4.7
 27000 -38.3 -36.9  315  56 29  10.0   5.5 | -38.6 -37.5  320  59 30   8.5   4.7
 26000 -35.5 -31.9  315  56 29   9.2   5.1 | -35.9 -32.6  320  56 29   8.9   4.9
 25000 -32.8 -27.0  320  56 29   9.3   5.1 | -33.3 -27.9  315  54 28   8.9   4.9
 24000 -30.0 -22.0  320  56 29   9.4   5.1 | -30.6 -23.1  315  51 26   9.0   4.9
 23000 -27.5 -17.5  325  56 29   8.1   4.4 | -28.1 -18.6  315  50 26   8.1   4.5
 22000 -25.1 -13.2  325  56 29   8.1   4.4 | -25.7 -14.3  310  50 26   8.2   4.5
 21000 -22.7  -8.9  330  55 28   8.1   4.4 | -23.2  -9.8  310  50 26   8.2   4.5
 20000 -20.4  -4.7  330  54 28   7.7   4.2 | -20.8  -5.4  310  50 26   8.2   4.5
 19500 -19.2  -2.6  330  53 27   7.7   4.2 | -19.6  -3.3  310  49 25   8.2   4.5
 19000 -18.1  -0.6  330  52 27   7.7   4.2 | -18.4  -1.1  310  49 25   8.2   4.5
 18500 -17.0   1.4  330  51 26   7.7   4.2 | -17.1   1.2  310  49 25   8.2   4.5
 18000 -15.8   3.6  330  50 26   7.7   4.2 | -15.9   3.4  310  49 25   8.3   4.6
 17500 -14.7   5.5  330  49 25   7.7   4.2 | -14.7   5.5  315  49 25   8.3   4.6
 17000 -13.5   7.7  330  47 24   7.4   4.1 | -13.4   7.9  315  50 26   8.4   4.6
 16500 -11.9  10.6  330  45 23   7.2   3.9 | -11.6  11.1  315  52 27   8.4   4.6
 16000 -10.9  12.4  330  44 23   7.8   4.3 | -10.3  13.5  315  54 28   7.9   4.3
 15500  -9.7  14.5  330  43 22   8.0   4.4 |  -9.2  15.4  320  56 29   7.7   4.2
 15000  -8.5  16.7  330  42 22   7.9   4.3 |  -8.0  17.6  320  58 30   7.5   4.1
 14500  -7.3  18.9  330  42 22   7.8   4.3 |  -7.0  19.4  320  58 30   7.1   3.9
 14000  -6.2  20.8  330  42 22   7.9   4.3 |  -5.9  21.4  320  58 30   7.0   3.9
 13500  -4.9  23.2  325  44 22   8.4   4.6 |  -4.9  23.2  320  57 29   6.6   3.6
 13000  -3.7  25.3  320  46 24   8.6   4.7 |  -3.9  25.0  320  56 29   6.6   3.6
 12500  -2.8  27.0  320  46 24   4.2   2.3 |  -3.0  26.6  320  56 29   6.0   3.3
 12000  -2.1  28.2  315  45 23   4.6   2.5 |  -2.1  28.2  320  55 28   6.2   3.4
 11500  -1.4  29.5  315  45 23   5.0   2.7 |  -1.2  29.8  315  54 28   5.7   3.1
 11000  -0.7  30.7  310  46 24   5.3   2.9 |  -0.4  31.3  315  52 27   5.9   3.2
 10500  -0.2  31.6  305  46 24   1.5   0.8 |   0.3  32.5  310  50 26   4.0   2.2
 10250  -0.0  32.0  305  45 23   2.2   1.2 |   0.6  33.1  310  49 25   4.3   2.3
 10000   0.2  32.4  300  44 23   4.4   2.4 |   1.0  33.8  310  49 25   4.4   2.4
  9750   0.6  33.1  300  44 23   4.3   2.4 |   1.3  34.3  305  47 24   4.3   2.4
  9500   0.8  33.4  295  42 21   3.0   1.7 |   1.6  34.9  305  46 24   4.1   2.2
  9250   1.0  33.8  295  39 20   3.0   1.6 |   1.9  35.4  300  44 23   4.4   2.4
  9000   1.3  34.3  290  37 19   4.5   2.4 |   2.2  36.0  300  42 22   3.5   1.9
  8750   1.7  35.1  290  35 18   5.2   2.9 |   2.4  36.3  295  40 21   3.5   1.9
  8500   2.0  35.6  290  32 16   4.4   2.4 |   2.7  36.9  295  37 19   4.6   2.5
  8250   2.3  36.1  285  29 15   4.2   2.3 |   3.0  37.4  295  35 18   3.7   2.0
  8000   2.7  36.9  285  26 13   5.8   3.2 |   3.4  38.1  290  32 16   6.2   3.4
  7750   3.2  37.8  280  22 11   6.3   3.5 |   3.9  39.0  290  29 15   7.3   4.0
  7500   3.6  38.5  275  19 10   5.0   2.7 |   4.4  39.9  290  26 13   5.7   3.1
  7250   4.0  39.2  270  16  8   5.3   2.9 |   4.8  40.6  290  23 12   6.0   3.3
  7000   4.4  39.9  265  14  7   5.8   3.2 |   5.3  41.5  285  20 10   6.7   3.7
  6750   4.8  40.6  255  12  6   6.7   3.7 |   5.8  42.4  285  18  9   7.0   3.8
  6500   5.4  41.7  240  11  6   7.5   4.1 |   6.3  43.3  280  15  8   7.2   4.0
  6250   5.9  42.6  225  10  5   5.5   3.0 |   6.8  44.2  275  13  7   5.1   2.8
  6000   6.2  43.2  215  10  5   2.7   1.5 |   7.1  44.8  270  11  6   2.5   1.4
  5750   6.2  43.2  205   9  5  -1.3  -0.7 |   7.0  44.6  255   9  5  -8.2  -4.5
  5500   5.7  42.3  190   7  4  -7.8  -4.3 |   5.5  41.9  225   6  3 -25.9 -14.2
________________________________________________________________________________

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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