Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 291240
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0640 MDT Sunday, March 29, 2015

This forecast is for Sunday, March 29, 2015:

If the trigger temperature of 61.1 F/16.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 551 ft/min (2.8 m/s)
   Maximum height of thermals.................. 12085 ft MSL (6800 ft AGL)

Forecast maximum temperature................... 65.0 F/18.8 C
Time of trigger temperature.................... 1345 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................. 7435 ft MSL (2149 ft AGL)
Thermal soaring outlook for Monday 03/30....... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 13394 ft MSL (8109 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 30103 ft MSL (24818 ft AGL)
Wave soaring outlook for Monday 03/30.......... Poor

Remarks...

Sunrise/Sunset.................... 06:48:43 / 19:19:25 MDT
Total possible sunshine........... 12 hr 30 min 43 sec (750 min 43 sec)
Altitude of sun at 13:04:13 MDT... 53.72 degrees

Upper air data from rawinsonde observation taken on 03/29/2015 at 0600 MDT

Freezing level.................. 10953 ft MSL (5668 ft AGL)
Convective condensation level... 18164 ft MSL (12879 ft AGL)
Lifted condensation level....... 16839 ft MSL (11553 ft AGL)
Lifted index.................... +3.4
K index......................... -12.2

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  -62.9 -81.2   275   37   19   8.0   4.4   91.7 197.1    42.3      M    M
 45000  -53.3 -63.9   270   62   32   7.3   4.0   83.3 182.0    40.1      M    M
 40000  -45.4 -49.7   275   66   34   5.0   2.7   71.5 160.7    35.1      M    M
 38000  -42.4 -44.3   265   65   33   6.7   3.7   67.3 153.2    33.2      M    M
 36000  -45.4 -49.7   260   59   30  -5.2  -2.9   54.6 130.3    25.2      M    M
 34000  -46.8 -52.2   255   55   28 -15.3  -8.4   44.3 111.7    18.5      M    M
 32000  -46.5 -51.7   265   57   29   6.4   3.5   36.6  97.9    13.4      M    M
 30000  -42.0 -43.6   270   59   30   8.6   4.7   34.8  94.6    12.3      M    M
 29000  -39.5 -39.1   270   58   30   9.0   5.0   34.3  93.7    12.1      M    M
 28000  -38.1 -36.6   270   57   29   4.9   2.7   31.3  88.3    10.0      M    M
 27000  -36.1 -33.0   275   56   29   8.6   4.7   30.1  86.2     9.2      M    M
 26000  -33.8 -28.8   275   55   28   6.9   3.8   29.3  84.7     8.7      M    M
 25000  -31.9 -25.4   275   54   28   6.0   3.3   28.0  82.4     7.7      M    M
 24000  -30.0 -22.0   280   54   28   9.2   5.0   26.8  80.2     6.9      M    M
 23000  -27.2 -17.0   285   54   28   7.9   4.3   26.6  80.0     6.8      M    M
 22000  -25.4 -13.7   285   54   28   7.3   4.0   25.3  77.5     5.8      M    M
 21000  -22.6  -8.7   290   54   28   9.4   5.2   25.1  77.2     5.7      M    M
 20000  -20.2  -4.4   290   54   28   4.2   2.3   24.5  76.1     5.2      M    M
 19500  -19.6  -3.3   290   53   27   4.6   2.5   23.5  74.4     4.4      M    M
 19000  -18.9  -2.0   290   52   27   6.2   3.4   22.7  72.8     3.7      M    M
 18500  -17.7   0.1   290   52   27   8.5   4.7   22.4  72.3     3.5      M    M
 18000  -16.4   2.5   290   51   26   8.6   4.7   22.2  71.9     3.3      M    M
 17500  -15.1   4.8   295   50   26   8.6   4.7   22.0  71.5     3.1      M    M
 17000  -13.8   7.2   295   49   25   8.6   4.7   21.8  71.2     3.0      M    M
 16500  -12.5   9.5   300   49   25   8.6   4.7   21.6  70.9     2.9      M    M
 16000  -11.3  11.7   300   48   25   8.6   4.7   21.5  70.7     2.8      M    M
 15500  -10.0  14.0   300   48   25   8.6   4.7   21.3  70.3     2.6      M    M
 15000   -8.7  16.3   300   48   25   8.6   4.7   21.1  69.9     2.4      M    M
 14500   -7.4  18.7   300   48   25   8.6   4.7   20.9  69.5     2.2      M    M
 14000   -5.5  22.1   300   47   24   9.3   5.1   20.6  69.0     2.0      M    M
 13500   -4.7  23.5   300   44   23  -2.3  -1.3   19.8  67.6     1.3      M    M
 13000   -4.2  24.4   300   41   21  11.1   6.1   18.9  66.0     0.4      M    M
 12500   -2.7  27.1   300   38   20   8.2   4.5   18.9  65.9     0.3      M    M
 12000   -1.8  28.8   300   35   18   6.4   3.5   18.3  65.0    -0.2    536  2.7
 11500   -0.9  30.4   300   31   16   6.3   3.5   17.7  63.9    -0.7    494  2.5
 11000    0.0  32.0   300   27   14   6.2   3.4   17.2  62.9    -1.3    452  2.3
 10500    1.0  33.8   305   23   12   7.7   4.2   16.8  62.2    -1.7    407  2.1
 10250    1.6  34.9   305   21   11   8.5   4.7   16.6  61.9    -1.9    381  1.9
 10000    2.3  36.1   305   20   10   9.3   5.1   16.6  61.8    -1.9    354  1.8
  9750    3.0  37.4   305   18   10   9.1   5.0   16.5  61.7    -2.0    326  1.7
  9500    3.7  38.7   310   17    9   9.1   5.0   16.5  61.6    -2.0    299  1.5
  9250    4.3  39.7   310   16    8   9.1   5.0   16.4  61.5    -2.1    271  1.4
  9000    5.0  41.0   310   15    8   9.1   5.0   16.4  61.5    -2.1    243  1.2
  8750    5.7  42.3   310   14    7   9.1   5.0   16.3  61.4    -2.2    216  1.1
  8500    6.4  43.5   310   14    7   9.2   5.0   16.3  61.3    -2.3    188  1.0
  8250    7.0  44.6   305   13    7   9.0   4.9   16.2  61.2    -2.3    160  0.8
  8000    7.7  45.9   305   13    7   9.6   5.3   16.2  61.1    -2.4    133  0.7
  7750    8.4  47.1   315   11    6   7.2   4.0   16.1  61.0    -2.5    105  0.5
  7500    8.7  47.7   325   10    5   3.3   1.8   15.7  60.3    -2.9     87  0.4
  7250    9.0  48.2   340    8    4   3.1   1.7   15.2  59.4    -3.4     73  0.4
  7000    9.2  48.6   355    8    4   2.6   1.4   14.7  58.5    -3.9     60  0.3
  6750    9.4  48.9   020    9    5   5.0   2.7   14.2  57.5    -4.5     46  0.2
  6500    9.6  49.3   035   11    6  -4.1  -2.2   13.7  56.6    -5.0     32  0.2
  6250    8.6  47.5   045   14    7 -16.3  -8.9   12.0  53.6    -6.7     54  0.3
  6000    7.6  45.7   055   17    9  -4.7  -2.6   10.3  50.6    -8.5     77  0.4
  5750    7.8  46.0   060   13    7   5.7   3.1    9.8  49.6    -9.1     65  0.3
  5500    7.9  46.2   075    9    5  -2.6  -1.5    9.3  48.7    -9.7     53  0.3

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

           03/29/2015 at 0900 MDT          |       03/29/2015 at 1200 MDT
                                           |
K index... -2.2  LI... +278.7              | K index... -8.6  LI... +279.4
CAPE... 0.0  CIN... -0.3                   | 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 -60.2 -76.4  275  41 21   4.7   2.6 | -59.5 -75.1  270  45 23   3.6   2.0
 45000 -53.1 -63.6  285  54 28   4.9   2.7 | -54.0 -65.2  280  61 31   4.0   2.2
 40000 -45.8 -50.4  270  64 33   4.9   2.7 | -47.9 -54.2  280  64 33   4.0   2.2
 38000 -45.7 -50.3  270  63 32  -2.2  -1.2 | -48.1 -54.6  280  63 32  -2.7  -1.5
 36000 -47.2 -53.0  275  58 30  -2.2  -1.2 | -49.7 -57.5  285  60 31  -2.6  -1.5
 34000 -47.6 -53.7  280  54 28   2.7   1.5 | -50.2 -58.4  290  53 27   3.8   2.1
 32000 -45.9 -50.6  285  50 26   2.7   1.5 | -47.9 -54.2  305  43 22   3.8   2.1
 30000 -43.7 -46.7  290  47 24   5.8   3.2 | -44.8 -48.6  320  40 21   7.5   4.1
 29000 -41.9 -43.4  295  47 24   5.9   3.2 | -42.5 -44.5  325  42 22   7.5   4.1
 28000 -40.2 -40.4  295  46 24   5.9   3.2 | -40.3 -40.5  325  44 23   7.5   4.1
 27000 -38.3 -36.9  300  46 24   7.7   4.2 | -37.9 -36.2  325  45 23   8.8   4.8
 26000 -35.9 -32.6  300  45 23   7.8   4.3 | -35.3 -31.5  325  45 23   8.6   4.7
 25000 -33.6 -28.5  305  45 23   7.8   4.3 | -32.7 -26.9  325  44 23   8.6   4.7
 24000 -31.2 -24.2  305  44 23   8.1   4.4 | -30.2 -22.4  325  44 23   8.1   4.4
 23000 -28.8 -19.8  305  43 22   8.2   4.5 | -27.8 -18.0  320  44 23   8.0   4.4
 22000 -26.3 -15.3  310  42 22   8.2   4.5 | -25.3 -13.5  320  44 23   8.0   4.4
 21000 -23.9 -11.0  310  41 21   8.3   4.6 | -22.9  -9.2  315  44 23   8.3   4.5
 20000 -21.4  -6.5  310  42 22   8.3   4.6 | -20.4  -4.7  310  42 21   8.3   4.5
 19500 -20.1  -4.2  310  42 22   8.3   4.6 | -19.2  -2.6  310  41 21   8.3   4.5
 19000 -18.9  -2.0  305  42 22   8.3   4.6 | -18.0  -0.4  310  39 20   8.3   4.6
 18500 -17.0   1.4  305  43 22   8.5   4.7 | -16.7   1.9  310  38 20   8.0   4.4
 18000 -15.7   3.7  305  44 23   8.5   4.7 | -15.5   4.1  310  36 19   8.0   4.4
 17500 -14.4   6.1  305  44 23   8.4   4.6 | -13.9   7.0  310  33 17   6.5   3.5
 17000 -13.2   8.2  305  44 23   8.4   4.6 | -12.9   8.8  310  32 16   6.6   3.6
 16500 -12.0  10.4  305  44 23   8.0   4.4 | -11.8  10.8  315  31 16   7.2   3.9
 16000 -10.8  12.6  305  43 22   7.8   4.3 | -10.7  12.7  315  30 16   7.3   4.0
 15500  -9.6  14.7  305  42 22   7.4   4.1 |  -9.6  14.7  315  30 15   7.0   3.9
 15000  -8.6  16.5  310  41 21   6.6   3.6 |  -8.7  16.3  315  30 15   6.4   3.5
 14500  -7.6  18.3  310  40 21   6.6   3.6 |  -7.7  18.1  315  30 15   6.4   3.5
 14000  -6.7  19.9  310  38 20   5.9   3.3 |  -6.8  19.8  315  28 15   6.1   3.3
 13500  -5.8  21.6  310  36 18   6.1   3.4 |  -5.9  21.4  315  27 14   6.1   3.4
 13000  -5.1  22.8  310  33 17   4.4   2.4 |  -5.1  22.8  315  25 13   5.0   2.8
 12500  -4.4  24.1  310  30 15   4.6   2.6 |  -4.4  24.1  315  23 12   5.1   2.8
 12000  -3.7  25.3  310  26 13   4.3   2.4 |  -3.6  25.5  315  21 11   5.3   2.9
 11500  -3.1  26.4  310  22 11   4.4   2.4 |  -2.8  27.0  315  19 10   5.4   3.0
 11000  -2.5  27.5  310  19 10   4.2   2.3 |  -2.2  28.0  315  16  8   4.1   2.3
 10500  -1.9  28.6  315  16  8   4.4   2.4 |  -1.6  29.1  315  13  7   4.3   2.4
 10250  -1.6  29.1  315  14  7   2.8   1.5 |  -1.3  29.7  315  12  6   3.4   1.9
 10000  -1.4  29.5  315  14  7   3.6   2.0 |  -1.0  30.2  315  11  6   3.8   2.1
  9750  -1.0  30.2  320  13  7   6.6   3.6 |  -0.7  30.7  320  10  5   5.0   2.8
  9500  -0.5  31.1  325  13  7   6.4   3.5 |  -0.3  31.5  325   8  4   4.9   2.7
  9250  -0.1  31.8  335  13  7   5.4   2.9 |  -0.0  32.0  330   7  4   4.7   2.6
  9000   0.3  32.5  340  14  7   5.1   2.8 |   0.3  32.5  335   7  4   4.8   2.6
  8750   0.7  33.3  345  14  7   6.4   3.5 |   0.7  33.3  340   6  3   5.6   3.1
  8500   1.2  34.2  350  15  8   6.4   3.5 |   1.2  34.2  355   6  3   5.7   3.1
  8250   1.6  34.9  350  16  8   5.6   3.1 |   1.5  34.7  005   5  3   5.4   3.0
  8000   2.0  35.6  355  16  8   5.6   3.1 |   1.9  35.4  020   5  2   5.3   2.9
  7750   2.4  36.3  355  17  9   6.0   3.3 |   2.4  36.3  035   5  2   8.6   4.7
  7500   2.9  37.2  360  17  9   5.4   3.0 |   3.1  37.6  040   5  2  10.6   5.8
  7250   3.2  37.8  005  17  9   4.7   2.6 |   3.9  39.0  040   5  2   9.6   5.2
  7000   3.6  38.5  005  17  9   4.7   2.6 |   4.6  40.3  040   5  2   9.7   5.3
  6750   4.0  39.2  010  17  9   5.5   3.0 |   5.3  41.5  045   5  2  10.1   5.6
  6500   4.4  39.9  010  16  8   5.6   3.1 |   6.1  43.0  040   5  2  10.6   5.8
  6250   4.7  40.5  015  14  7   4.3   2.4 |   6.9  44.4  045   4  2  10.8   5.9
  6000   5.1  41.2  025  12  6   6.1   3.4 |   7.7  45.9  045   4  2   9.9   5.5
  5750   5.7  42.3  025  10  5  11.2   6.2 |   8.6  47.5  045   4  2  15.2   8.4
  5500   6.7  44.1  030   7  4  15.3   8.4 |  10.1  50.2  045   4  2  26.4  14.5

           03/29/2015 at 1500 MDT          |       03/29/2015 at 1800 MDT
                                           |
K index... -0.7  LI... +277.2              | K index... +4.2  LI... +275.1
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -59.5 -75.1  275  49 25   3.2   1.8 | -59.1 -74.4  275  46 24   3.3   1.8
 45000 -54.5 -66.1  280  64 33   3.7   2.0 | -54.2 -65.6  280  59 30   1.4   0.8
 40000 -48.9 -56.0  275  66 34   3.8   2.1 | -52.1 -61.8  280  64 33   1.4   0.7
 38000 -49.5 -57.1  275  63 32  -3.6  -2.0 | -52.6 -62.7  280  62 32  -1.9  -1.0
 36000 -51.7 -61.1  280  59 30  -3.6  -2.0 | -53.7 -64.7  285  57 29  -1.9  -1.0
 34000 -52.2 -62.0  290  53 27   5.4   2.9 | -53.6 -64.5  290  51 26   5.9   3.2
 32000 -49.0 -56.2  295  45 23   5.4   2.9 | -49.5 -57.1  300  45 23   6.1   3.3
 30000 -45.2 -49.4  305  41 21   8.1   4.4 | -45.3 -49.5  305  41 21   8.2   4.5
 29000 -42.7 -44.9  310  41 21   8.0   4.4 | -42.9 -45.2  310  41 21   8.2   4.5
 28000 -40.3 -40.5  315  42 22   8.0   4.4 | -40.4 -40.7  310  41 21   8.3   4.5
 27000 -37.8 -36.0  320  42 22   9.0   4.9 | -37.9 -36.2  315  41 21   9.2   5.1
 26000 -35.2 -31.4  320  42 22   8.9   4.9 | -35.1 -31.2  315  40 20   9.2   5.0
 25000 -32.5 -26.5  320  42 21   8.9   4.9 | -32.4 -26.3  315  39 20   9.2   5.0
 24000 -29.8 -21.6  320  41 21   8.6   4.7 | -29.7 -21.5  310  38 19   8.7   4.8
 23000 -27.2 -17.0  320  39 20   8.6   4.7 | -27.0 -16.6  310  37 19   8.7   4.8
 22000 -24.7 -12.5  320  38 19   8.6   4.7 | -24.4 -11.9  305  36 18   8.7   4.8
 21000 -22.1  -7.8  320  36 19   8.6   4.7 | -21.8  -7.2  300  35 18   8.3   4.6
 20000 -19.5  -3.1  320  36 18   8.6   4.7 | -19.3  -2.7  300  35 18   8.3   4.6
 19500 -18.2  -0.8  320  35 18   8.6   4.7 | -18.1  -0.6  300  34 18   8.3   4.6
 19000 -16.9   1.6  320  35 18   8.7   4.8 | -16.8   1.8  300  34 18   8.3   4.6
 18500 -15.7   3.7  320  34 18   7.5   4.1 | -15.6   3.9  300  34 17   7.7   4.2
 18000 -14.6   5.7  315  34 17   7.6   4.2 | -14.5   5.9  295  32 17   7.8   4.3
 17500 -12.9   8.8  315  33 17   7.4   4.1 | -13.3   8.1  295  31 16   7.5   4.1
 17000 -11.8  10.8  315  32 17   7.5   4.1 | -12.2  10.0  295  31 16   7.4   4.1
 16500 -10.7  12.7  315  31 16   7.0   3.9 | -10.5  13.1  290  31 16   7.8   4.3
 16000  -9.7  14.5  310  30 15   6.9   3.8 |  -9.4  15.1  290  30 16   7.8   4.3
 15500  -8.6  16.5  310  28 14   6.8   3.7 |  -8.2  17.2  285  30 15   7.9   4.3
 15000  -7.6  18.3  305  27 14   6.6   3.6 |  -7.1  19.2  285  29 15   7.9   4.3
 14500  -6.7  19.9  305  26 13   6.7   3.7 |  -5.9  21.4  285  29 15   7.8   4.3
 14000  -5.6  21.9  300  25 13   7.6   4.2 |  -4.8  23.4  285  29 15   7.5   4.1
 13500  -4.5  23.9  295  26 13   7.6   4.2 |  -3.7  25.3  280  28 15   7.6   4.2
 13000  -3.4  25.9  290  25 13   7.3   4.0 |  -2.6  27.3  280  27 14   7.9   4.3
 12500  -2.3  27.9  290  25 13   7.4   4.1 |  -1.5  29.3  280  24 13   8.0   4.4
 12000  -1.3  29.7  285  24 12   7.4   4.1 |  -0.4  31.3  280  21 11   7.3   4.0
 11500  -0.2  31.6  280  22 12   7.8   4.3 |   0.7  33.3  275  18  9   7.5   4.1
 11000   0.6  33.1  275  19 10   4.2   2.3 |   1.6  34.9  270  16  8   5.4   2.9
 10500   1.3  34.3  275  15  8   4.7   2.6 |   2.4  36.3  260  14  7   5.8   3.2
 10250   1.5  34.7  270  14  7   1.4   0.8 |   2.7  36.9  250  13  7   1.9   1.0
 10000   1.5  34.7  270  13  7   0.9   0.5 |   2.8  37.0  250  12  6   1.1   0.6
  9750   1.8  35.2  270   9  5   3.3   1.8 |   3.0  37.4  235  10  5   3.5   1.9
  9500   2.0  35.6  260   6  3   2.7   1.5 |   3.2  37.8  220   9  5   3.0   1.7
  9250   2.2  36.0  245   3  2   2.4   1.3 |   3.4  38.1  205   8  4   2.9   1.6
  9000   2.4  36.3  210   2  1   3.4   1.8 |   3.7  38.7  190   7  4   4.6   2.5
  8750   2.7  36.9  160   2  1   4.9   2.7 |   4.1  39.4  175   7  3   6.9   3.8
  8500   3.1  37.6  130   3  2   6.8   3.7 |   4.7  40.5  160   6  3   7.8   4.3
  8250   3.6  38.5  125   3  2   8.6   4.7 |   5.3  41.5  155   6  3   8.6   4.7
  8000   4.3  39.7  120   3  2   8.9   4.9 |   5.9  42.6  150   6  3   9.3   4.9
  7750   5.0  41.0  120   3  2  10.8   5.9 |   6.6  43.9  150   6  3  10.1   5.5
  7500   5.8  42.4  120   3  2  10.8   5.9 |   7.4  45.3  145   6  3  10.2   5.6
  7250   6.6  43.9  120   3  2   9.5   5.2 |   8.1  46.6  145   6  3   9.7   5.3
  7000   7.3  45.1  120   3  2   9.8   5.4 |   8.9  48.0  145   6  3   9.9   5.4
  6750   8.0  46.4  120   3  2  10.0   5.5 |   9.6  49.3  145   6  3   9.8   5.4
  6500   8.8  47.8  120   3  2  10.4   5.7 |  10.3  50.5  145   6  3   9.7   5.3
  6250   9.6  49.3  120   3  2  10.1   5.6 |  11.1  52.0  145   6  3   9.4   5.2
  6000  10.4  50.7  120   3  2  11.1   6.1 |  11.8  53.2  140   5  3  10.1   5.5
  5750  11.3  52.3  120   3  2  16.4   9.0 |  12.6  54.7  140   5  3  11.8   6.5
  5500  12.8  55.0  115   3  2  22.1  12.1 |  13.5  56.3  140   5  3  12.9   7.1
________________________________________________________________________________

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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