Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 140324
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
2024 MST Saturday, December 13, 2014

This forecast is for Sunday, December 14, 2014:

If the trigger temperature of 49.4 F/9.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5300 ft MSL (13 ft AGL)

Forecast maximum temperature................... 37.0 F/3.2 C
Time of trigger temperature.................... None
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................. None
Thermal soaring outlook for Monday 12/15....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 15845 ft MSL (10558 ft AGL)
Wave soaring outlook for Monday 12/15.......... Poor

Remarks...

Sunrise/Sunset.................... 07:12:44 / 16:35:47 MST
Total possible sunshine........... 9 hr 23 min 4 sec (563 min 4 sec)
Altitude of sun at 11:54:19 MST... 27.06 degrees

Upper air data from numerical model forecast valid on 12/14/2014 at 0500 MST

Freezing level.................. 8352 ft MSL (3065 ft AGL)
Convective condensation level... 10943 ft MSL (5656 ft AGL)
Lifted condensation level....... 7511 ft MSL (2224 ft AGL)
Lifted index.................... +9.4
K index......................... +19.2

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  -57.3 -71.1   250   21   11   1.3   0.7      M     M       M      M    M
 45000  -55.4 -67.7   240   26   13   1.2   0.7      M     M       M      M    M
 40000  -52.1 -61.8   195   35   18   2.1   1.2      M     M       M      M    M
 38000  -51.0 -59.8   190   39   20   1.1   0.6      M     M       M      M    M
 36000  -50.3 -58.5   190   41   21   1.2   0.6      M     M       M      M    M
 34000  -49.7 -57.5   190   42   22   1.2   0.7      M     M       M      M    M
 32000  -48.8 -55.8   185   46   24   1.4   0.7      M     M       M      M    M
 30000  -48.0 -54.4   185   50   26   2.8   1.5      M     M       M      M    M
 29000  -45.9 -50.6   185   49   25   7.7   4.2   26.8  80.3    18.2      M    M
 28000  -43.6 -46.5   185   47   24   7.7   4.2   26.0  78.7    17.8      M    M
 27000  -40.8 -41.4   190   44   23   7.5   4.1   25.1  77.1    17.4      M    M
 26000  -38.2 -36.8   185   42   22   9.1   5.0   24.6  76.3    17.2      M    M
 25000  -35.4 -31.7   185   40   21   9.1   5.0   24.4  75.8    17.2      M    M
 24000  -32.7 -26.9   185   38   19   9.2   5.0   24.2  75.6    17.3      M    M
 23000  -30.2 -22.4   185   35   18   8.2   4.5   23.7  74.7    17.2      M    M
 22000  -27.7 -17.9   185   33   17   8.2   4.5   23.1  73.6    16.8      M    M
 21000  -25.3 -13.5   185   30   15   8.2   4.5   22.6  72.8    16.6      M    M
 20000  -23.0  -9.4   185   26   13   7.6   4.2   21.9  71.4    16.1      M    M
 19500  -21.9  -7.4   185   24   12   7.6   4.2   21.5  70.7    15.9      M    M
 19000  -20.8  -5.4   185   21   11   7.6   4.2   21.1  70.0    15.6      M    M
 18500  -19.7  -3.5   185   19   10   7.8   4.3   20.8  69.4    15.4      M    M
 18000  -18.6  -1.5   180   18    9   6.2   3.4   20.4  68.7    15.1      M    M
 17500  -17.7   0.1   180   17    9   6.2   3.4   19.7  67.5    14.6      M    M
 17000  -16.8   1.8   180   17    9   6.2   3.4   19.1  66.4    14.2      M    M
 16500  -15.9   3.4   180   18    9   6.4   3.5   18.5  65.4    13.7      M    M
 16000  -14.9   5.2   175   19   10   6.4   3.5   18.0  64.4    13.3      M    M
 15500  -14.0   6.8   175   19   10   7.1   3.9   17.5  63.5    12.9      M    M
 15000  -12.9   8.8   175   20   10   7.1   3.9   17.0  62.6    12.5      M    M
 14500  -11.9  10.6   175   20   10   6.8   3.7   16.6  61.8    12.1      M    M
 14000  -10.5  13.1   175   19   10   6.8   3.7   15.8  60.5    11.5      M    M
 13500   -9.5  14.9   175   16    8   6.2   3.4   15.3  59.5    11.0      M    M
 13000   -8.6  16.5   170   12    6   6.4   3.5   14.7  58.5    10.5      M    M
 12500   -7.8  18.0   160    8    4   4.4   2.4   14.0  57.2     9.9      M    M
 12000   -7.1  19.2   120    3    2   4.5   2.5   13.2  55.7     9.3      M    M
 11500   -6.3  20.7   055    5    2   5.5   3.0   12.4  54.4     8.6      M    M
 11000   -5.5  22.1   040    8    4   5.4   3.0   11.7  53.1     8.0      M    M
 10500   -4.7  23.5   035   12    6   6.0   3.3   11.1  52.0     7.4      M    M
 10250   -4.4  24.1   035   14    7   6.1   3.3   10.8  51.4     7.1      M    M
 10000   -3.9  25.0   035   17    9   8.1   4.4   10.6  51.0     6.8      M    M
  9750   -3.3  26.1   035   19   10   9.2   5.0   10.5  50.9     6.7      M    M
  9500   -2.6  27.3   030   20   10   8.6   4.7   10.4  50.8     6.6      M    M
  9250   -2.0  28.4   030   20   10   8.8   4.8   10.4  50.6     6.6      M    M
  9000   -1.3  29.7   025   21   11   8.6   4.7   10.3  50.5     6.5      M    M
  8750   -0.7  30.7   025   22   11   7.1   3.9   10.1  50.3     6.4      M    M
  8500   -0.3  31.5   020   22   11   6.4   3.5    9.9  49.8     6.2      M    M
  8250    0.2  32.4   020   23   12   6.1   3.4    9.6  49.3     6.0      M    M
  8000    0.7  33.3   015   23   12   7.9   4.3    9.4  48.9     5.8      M    M
  7750    1.4  34.5   010   23   12   7.9   4.3    9.3  48.7     5.7      M    M
  7500    1.8  35.2   010   22   11   6.2   3.4    9.0  48.3     5.4      M    M
  7250    2.3  36.1   005   21   11   6.6   3.6    8.8  47.8     5.2      M    M
  7000    2.8  37.0   005   19   10   6.3   3.5    8.6  47.4     5.0      M    M
  6750    3.2  37.8   005   16    8   4.5   2.5    8.2  46.8     4.7      M    M
  6500    3.5  38.3   005   13    7   3.7   2.0    7.8  46.0     4.2      M    M
  6250    3.7  38.7   005   10    5   2.6   1.4    7.3  45.2     3.8      M    M
  6000    3.9  39.0   010    6    3   1.0   0.5    6.7  44.0     3.2      M    M
  5750    4.0  39.2   010    3    2  -0.7  -0.4    6.0  42.8     2.6      M    M
  5500    3.7  38.7   230    1    1  -8.3  -4.6    5.0  40.9     1.6      M    M

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

           12/14/2014 at 0800 MST          |       12/14/2014 at 1100 MST
                                           |
K index... +19.1  LI... +3.6               | K index... +18.6  LI... +3.2
CAPE... 0.0  CIN... -0.5                   | CAPE... 0.0  CIN... -5.8
                                           |
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 -56.8 -70.2  255  21 11   1.4   0.8 | -57.3 -71.1  270  22 12   1.5   0.8
 45000 -54.7 -66.5  255  18  9   1.4   0.7 | -55.0 -67.0  265  22 11   1.5   0.8
 40000 -51.9 -61.4  215  23 12   1.8   1.0 | -51.0 -59.8  250  21 11   2.6   1.4
 38000 -51.0 -59.8  200  26 13   0.9   0.5 | -49.9 -57.8  240  20 10   0.5   0.3
 36000 -50.5 -58.9  195  27 14   0.9   0.5 | -49.6 -57.3  215  19 10   0.5   0.3
 34000 -49.9 -57.8  185  29 15   0.9   0.5 | -49.3 -56.7  195  21 11   0.6   0.3
 32000 -48.8 -55.8  180  37 19   2.0   1.1 | -48.3 -54.9  170  30 15   1.9   1.0
 30000 -47.7 -53.9  175  46 24   2.4   1.3 | -47.2 -53.0  155  42 22   2.3   1.3
 29000 -45.8 -50.4  175  46 24   7.1   3.9 | -45.3 -49.5  155  43 22   7.1   3.9
 28000 -43.1 -45.6  175  45 23   7.1   3.9 | -43.2 -45.8  150  42 21   7.1   3.9
 27000 -41.0 -41.8  170  44 22   7.1   3.9 | -40.6 -41.1  145  40 21   7.0   3.8
 26000 -38.8 -37.8  170  41 21   7.8   4.3 | -38.2 -36.8  150  38 19   8.5   4.6
 25000 -36.4 -33.5  170  38 20   7.8   4.3 | -35.7 -32.3  155  34 18   8.5   4.7
 24000 -34.1 -29.4  170  35 18   7.8   4.3 | -33.1 -27.6  160  31 16   8.5   4.7
 23000 -31.6 -24.9  170  32 17   9.1   5.0 | -30.8 -23.4  165  27 14   7.6   4.2
 22000 -28.8 -19.8  175  29 15   9.1   5.0 | -28.5 -19.3  170  23 12   7.6   4.2
 21000 -26.1 -15.0  180  25 13   9.2   5.1 | -26.2 -15.2  175  20 10   7.6   4.2
 20000 -23.6 -10.5  180  23 12   8.0   4.4 | -23.9 -11.0  180  16  8   7.8   4.3
 19500 -22.4  -8.3  180  22 11   8.1   4.4 | -22.7  -8.9  180  14  7   7.8   4.3
 19000 -21.2  -6.2  180  21 11   8.1   4.4 | -21.6  -6.9  185  12  6   7.9   4.3
 18500 -20.0  -4.0  180  20 10   8.1   4.5 | -20.4  -4.7  190  11  5   7.9   4.3
 18000 -18.9  -2.0  185  19 10   7.3   4.0 | -19.2  -2.6  190   9  5   7.5   4.1
 17500 -17.8  -0.0  185  18  9   7.2   4.0 | -18.1  -0.6  195   8  4   7.4   4.1
 17000 -16.8   1.8  185  18  9   6.9   3.8 | -17.0   1.4  200   7  4   7.1   3.9
 16500 -15.9   3.4  185  17  9   6.1   3.4 | -16.1   3.0  195   5  3   6.3   3.5
 16000 -15.0   5.0  185  16  8   6.1   3.4 | -15.2   4.6  185   3  1   6.5   3.6
 15500 -14.1   6.6  180  15  8   6.4   3.5 | -14.3   6.3  120   1  1   4.9   2.7
 15000 -13.1   8.4  180  14  7   6.5   3.6 | -13.6   7.5  055   3  1   5.2   2.8
 14500 -12.3   9.9  175  13  6   5.9   3.2 | -12.9   8.8  040   5  3   4.6   2.5
 14000 -11.0  12.2  170   9  5   5.8   3.2 | -12.0  10.4  030   9  5   4.2   2.3
 13500 -10.2  13.6  160   6  3   5.8   3.2 | -11.1  12.0  025  11  5   8.2   4.5
 13000  -9.4  15.1  130   3  2   5.9   3.2 |  -9.9  14.2  015  12  6   8.4   4.6
 12500  -8.5  16.7  065   3  1   5.8   3.2 |  -9.0  15.8  010  13  7   3.3   1.8
 12000  -7.5  18.5  035   4  2   6.0   3.3 |  -8.4  16.9  005  13  7   3.4   1.9
 11500  -6.7  19.9  025   6  3   4.7   2.6 |  -7.7  18.1  360  14  7   6.5   3.6
 11000  -6.0  21.2  020   7  4   4.9   2.7 |  -6.8  19.8  355  14  7   6.5   3.6
 10500  -5.4  22.3  025   9  5   4.5   2.5 |  -5.9  21.4  355  13  7   6.5   3.6
 10250  -5.1  22.8  030  10  5   4.2   2.3 |  -5.4  22.3  360  13  7   6.7   3.7
 10000  -4.8  23.4  030  11  6   6.9   3.8 |  -5.0  23.0  005  12  6   5.8   3.2
  9750  -4.3  24.3  035  13  7   6.9   3.8 |  -4.7  23.5  005  12  6   2.0   1.1
  9500  -3.9  25.0  030  16  8   4.4   2.4 |  -4.6  23.7  010  14  7   0.2   0.1
  9250  -3.5  25.7  030  18  9   5.3   2.9 |  -4.6  23.7  010  15  8   0.9   0.5
  9000  -3.2  26.2  030  20 11   4.3   2.4 |  -4.5  23.9  010  17  9  -0.2  -0.1
  8750  -2.9  26.8  030  22 11   3.4   1.9 |  -4.5  23.9  010  18  9   1.5   0.8
  8500  -2.6  27.3  025  24 12   3.7   2.0 |  -4.3  24.3  010  21 11   3.8   2.1
  8250  -2.4  27.7  025  25 13   2.8   1.5 |  -4.0  24.8  010  23 12   3.0   1.7
  8000  -2.1  28.2  020  27 14   6.2   3.4 |  -3.8  25.2  010  26 13   4.0   2.2
  7750  -1.5  29.3  020  26 13   9.2   5.0 |  -3.4  25.9  005  26 14   5.7   3.1
  7500  -0.9  30.4  015  25 13   7.8   4.3 |  -3.0  26.6  005  25 13   6.0   3.3
  7250  -0.3  31.5  015  24 12   8.3   4.6 |  -2.6  27.3  005  24 13   6.1   3.3
  7000   0.4  32.7  015  22 11   9.4   5.1 |  -2.1  28.2  005  23 12   7.0   3.8
  6750   1.1  34.0  015  20 11   9.2   5.1 |  -1.6  29.1  005  20 10   7.6   4.1
  6500   1.8  35.2  010  18  9   8.8   4.8 |  -1.0  30.2  005  18  9   6.9   3.8
  6250   2.4  36.3  010  16  8   8.0   4.4 |  -0.5  31.1  005  16  8   8.9   4.9
  6000   3.0  37.4  010  14  7   7.3   4.0 |   0.3  32.5  005  15  8  10.8   5.9
  5750   3.5  38.3  005  11  5   5.0   2.8 |   1.0  33.8  005  14  7  10.1   5.6
  5500   3.6  38.5  355   7  3  -2.7  -1.5 |   1.8  35.2  005  13  7  11.3   6.2

           12/14/2014 at 1400 MST          |       12/14/2014 at 1700 MST
                                           |
K index... +17.5  LI... +2.9               | K index... +13.6  LI... +4.1
CAPE... 0.0  CIN... -0.6                   | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -56.8 -70.2  285  30 15   1.4   0.8 | -57.3 -71.1  295  37 19   1.8   1.0
 45000 -54.8 -66.6  290  34 18   1.3   0.7 | -54.6 -66.3  295  40 21   1.7   0.9
 40000 -50.3 -58.5  290  34 18   3.0   1.6 | -49.3 -56.7  290  40 20   3.5   1.9
 38000 -49.1 -56.4  285  31 16  -0.1  -0.1 | -48.2 -54.8  290  37 19  -0.9  -0.5
 36000 -49.2 -56.6  270  22 11  -0.1  -0.1 | -48.7 -55.7  285  28 15  -0.8  -0.5
 34000 -49.3 -56.7  240  16  8  -0.1  -0.0 | -49.2 -56.6  275  21 11  -0.7  -0.4
 32000 -48.0 -54.4  180  18  9   2.4   1.3 | -48.2 -54.8  235   9  5   1.9   1.0
 30000 -46.6 -51.9  155  32 16   2.5   1.4 | -47.0 -52.6  150  13  7   2.3   1.2
 29000 -44.9 -48.8  150  31 16   6.4   3.5 | -45.2 -49.4  135  18  9   7.2   4.0
 28000 -42.5 -44.5  145  29 15   6.4   3.5 | -42.5 -44.5  125  24 12   7.2   4.0
 27000 -40.6 -41.1  140  26 14   6.3   3.4 | -40.3 -40.5  120  29 15   7.2   3.9
 26000 -38.2 -36.8  135  24 12   9.3   5.1 | -37.9 -36.2  120  28 14   8.5   4.7
 25000 -35.4 -31.7  135  21 11   9.4   5.2 | -35.4 -31.7  120  23 12   8.5   4.7
 24000 -32.6 -26.7  130  18  9   9.3   5.1 | -32.9 -27.2  120  18 10   8.5   4.7
 23000 -30.1 -22.2  125  15  8   7.2   4.0 | -30.4 -22.7  115  14  7   8.3   4.5
 22000 -28.0 -18.4  120  11  6   7.2   3.9 | -27.9 -18.2  105  11  6   8.3   4.5
 21000 -25.9 -14.6  110   7  4   7.2   4.0 | -25.5 -13.9  085   9  5   8.5   4.6
 20000 -23.9 -11.0  095   4  2   6.4   3.5 | -23.4 -10.1  055   7  4   6.5   3.6
 19500 -22.9  -9.2  070   3  1   6.4   3.5 | -22.4  -8.3  040   6  3   6.5   3.6
 19000 -22.0  -7.6  030   3  1   6.4   3.5 | -21.4  -6.5  015   6  3   6.5   3.6
 18500 -21.0  -5.8  360   3  2   6.4   3.5 | -20.5  -4.9  360   7  4   6.5   3.5
 18000 -20.1  -4.2  345   5  2   6.7   3.7 | -19.5  -3.1  350   8  4   6.9   3.8
 17500 -19.1  -2.4  350   5  3   6.8   3.7 | -18.4  -1.1  345   9  4   7.0   3.9
 17000 -18.1  -0.6  355   6  3   7.0   3.8 | -17.4   0.7  345   9  5   7.1   3.9
 16500 -17.0   1.4  005   7  3   7.7   4.2 | -16.3   2.7  345   9  5   7.4   4.1
 16000 -15.9   3.4  015   7  4   7.7   4.2 | -15.2   4.6  345  10  5   7.6   4.1
 15500 -14.8   5.4  020   8  4   7.3   4.0 | -14.2   6.4  345  11  6   5.9   3.2
 15000 -13.7   7.3  020   9  5   7.3   4.0 | -13.4   7.9  340  12  6   6.1   3.3
 14500 -12.6   9.3  020  10  5   7.2   3.9 | -12.2  10.0  340  14  7   4.7   2.6
 14000 -11.1  12.0  015  12  6   7.3   4.0 | -11.5  11.3  335  17  9   4.7   2.6
 13500 -10.2  13.6  005  13  7   5.4   2.9 | -10.7  12.7  335  19 10   6.0   3.3
 13000  -9.3  15.3  360  15  8   5.6   3.1 |  -9.8  14.4  330  22 11   6.2   3.4
 12500  -8.6  16.5  350  16  8   4.7   2.6 |  -9.1  15.6  330  25 13   3.4   1.8
 12000  -7.9  17.8  345  18  9   4.6   2.5 |  -8.6  16.5  330  27 14   3.5   1.9
 11500  -7.1  19.2  340  19 10   5.6   3.0 |  -8.2  17.2  335  30 15   3.1   1.7
 11000  -6.3  20.7  335  20 10   5.8   3.2 |  -7.7  18.1  335  32 16   3.1   1.7
 10500  -5.7  21.7  330  21 11   3.1   1.7 |  -7.3  18.9  340  33 17   3.5   1.9
 10250  -5.5  22.1  330  22 11   3.1   1.7 |  -7.0  19.4  340  34 17   3.0   1.7
 10000  -5.2  22.6  330  22 11   3.2   1.8 |  -6.8  19.8  340  34 18   4.5   2.5
  9750  -5.0  23.0  330  23 12   2.4   1.3 |  -6.4  20.5  345  35 18   6.1   3.3
  9500  -4.9  23.2  335  23 12   1.8   1.0 |  -5.9  21.4  345  35 18   5.6   3.1
  9250  -4.8  23.4  340  24 12   1.9   1.1 |  -5.5  22.1  345  34 18   6.0   3.3
  9000  -4.6  23.7  345  24 13   2.0   1.1 |  -5.1  22.8  345  34 17   5.0   2.7
  8750  -4.5  23.9  345  25 13   2.3   1.2 |  -4.8  23.4  350  33 17   4.7   2.6
  8500  -4.3  24.3  350  27 14   2.4   1.3 |  -4.4  24.1  350  32 16   5.5   3.0
  8250  -4.1  24.6  355  29 15   2.0   1.1 |  -4.0  24.8  350  31 16   5.3   2.9
  8000  -3.9  25.0  355  30 16   3.4   1.8 |  -3.6  25.5  355  30 15   5.5   3.0
  7750  -3.6  25.5  355  29 15   4.8   2.6 |  -3.2  26.2  355  28 15   5.2   2.9
  7500  -3.3  26.1  355  28 14   4.5   2.5 |  -2.8  27.0  360  27 14   4.8   2.6
  7250  -3.0  26.6  355  26 13   4.8   2.6 |  -2.5  27.5  360  26 13   5.1   2.8
  7000  -2.6  27.3  355  24 12   6.9   3.8 |  -2.1  28.2  005  24 12   6.1   3.3
  6750  -2.0  28.4  355  22 11   8.2   4.5 |  -1.6  29.1  005  22 11   6.4   3.5
  6500  -1.5  29.3  355  20 10   7.0   3.9 |  -1.2  29.8  010  19 10   5.7   3.1
  6250  -0.9  30.4  355  17  9   9.1   5.0 |  -0.7  30.7  010  17  9   7.3   4.0
  6000  -0.1  31.8  355  16  8  11.3   6.2 |  -0.1  31.8  015  14  7   8.7   4.8
  5750   0.7  33.3  355  14  7  10.3   5.7 |   0.5  32.9  015  12  6   8.8   4.8
  5500   1.5  34.7  355  12  6  11.1   6.1 |   1.2  34.2  015   9  5   9.4   5.1
________________________________________________________________________________

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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