Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 020023
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1823 MDT Wednesday, April 1, 2015

This forecast is for Thursday, April 2, 2015:

If the trigger temperature of 49.2 F/9.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5307 ft MSL (0 ft AGL)

Forecast maximum temperature................... 40.0 F/4.9 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 Friday 04/03....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 34155 ft MSL (28848 ft AGL)
Wave soaring outlook for Friday 04/03.......... Poor

Remarks... None

Sunrise/Sunset.................... 06:42:20 / 19:23:26 MDT
Total possible sunshine........... 12 hr 41 min 7 sec (761 min 7 sec)
Altitude of sun at 13:03:02 MDT... 55.26 degrees

Upper air data from numerical model forecast valid on 04/02/2015 at 0600 MDT

Freezing level.................. 7686 ft MSL (2379 ft AGL)
Convective condensation level... 11088 ft MSL (5781 ft AGL)
Lifted condensation level....... 7988 ft MSL (2682 ft AGL)
Lifted index.................... +6.9
K index......................... +16.7

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  -55.5 -67.9   260   33   17   0.3   0.2      M     M       M      M    M
 45000  -55.0 -67.0   260   48   25   0.4   0.2      M     M       M      M    M
 40000  -55.4 -67.7   265   70   36  -0.3  -0.2      M     M       M      M    M
 38000  -55.3 -67.5   265   80   41   1.2   0.7      M     M       M      M    M
 36000  -54.4 -65.9   265   93   48   1.3   0.7      M     M       M      M    M
 34000  -53.6 -64.5   265  104   54   3.4   1.9      M     M       M      M    M
 32000  -50.8 -59.4   260   96   50   4.7   2.6      M     M       M      M    M
 30000  -47.9 -54.2   260   88   45   6.6   3.6   28.0  82.3    17.6      M    M
 29000  -45.7 -50.3   260   83   43   7.1   3.9   26.7  80.1    16.9      M    M
 28000  -43.6 -46.5   260   77   40   7.1   3.9   25.7  78.2    16.3      M    M
 27000  -41.5 -42.7   255   72   37   7.0   3.8   24.8  76.6    15.8      M    M
 26000  -39.0 -38.2   255   68   35   8.6   4.7   24.1  75.4    15.5      M    M
 25000  -36.4 -33.5   255   66   34   8.6   4.7   23.7  74.6    15.3      M    M
 24000  -33.9 -29.0   255   64   33   8.7   4.8   23.3  74.0    15.2      M    M
 23000  -31.6 -24.9   250   61   32   7.0   3.9   22.5  72.6    14.7      M    M
 22000  -29.5 -21.1   250   59   30   7.0   3.9   21.5  70.7    14.0      M    M
 21000  -27.4 -17.3   245   57   29   7.1   3.9   20.6  69.1    13.4      M    M
 20000  -24.9 -12.8   245   55   28   8.3   4.6   19.9  67.9    13.1      M    M
 19500  -23.7 -10.7   250   54   28   8.3   4.5   19.7  67.4    12.9      M    M
 19000  -22.4  -8.3   250   54   28   8.3   4.5   19.4  67.0    12.8      M    M
 18500  -21.2  -6.2   255   53   28   8.1   4.4   19.2  66.6    12.7      M    M
 18000  -19.1  -2.4   255   51   26   9.8   5.4   19.1  66.4    12.7      M    M
 17500  -17.6   0.3   255   49   25   9.9   5.4   19.2  66.5    12.8      M    M
 17000  -16.3   2.7   255   46   24   7.9   4.3   19.0  66.2    12.7      M    M
 16500  -15.1   4.8   255   43   22   8.2   4.5   18.7  65.7    12.5      M    M
 16000  -14.0   6.8   250   40   20   7.7   4.2   18.4  65.2    12.2      M    M
 15500  -12.9   8.8   250   36   19   7.6   4.2   18.0  64.5    11.9      M    M
 15000  -11.8  10.8   245   32   17   7.7   4.2   17.7  63.9    11.6      M    M
 14500  -10.7  12.7   245   30   15   7.7   4.2   17.3  63.2    11.3      M    M
 14000   -9.5  14.9   240   28   14   7.3   4.0   17.0  62.6    11.1      M    M
 13500   -8.5  16.7   240   26   13   6.2   3.4   16.5  61.7    10.7      M    M
 13000   -7.6  18.3   235   24   12   6.0   3.3   15.9  60.6    10.2      M    M
 12500   -6.9  19.6   230   22   11   4.3   2.4   15.1  59.2     9.5      M    M
 12000   -6.2  20.8   230   20   10   4.4   2.4   14.3  57.7     8.7      M    M
 11500   -5.6  21.9   225   17    9   4.6   2.5   13.4  56.1     8.0      M    M
 11000   -4.9  23.2   220   15    8   4.6   2.5   12.6  54.7     7.2      M    M
 10500   -4.3  24.3   215   11    6   4.4   2.4   11.7  53.1     6.4      M    M
 10250   -4.0  24.8   210   10    5   3.7   2.0   11.3  52.3     6.0      M    M
 10000   -3.7  25.3   205    8    4   6.4   3.5   10.9  51.6     5.6      M    M
  9750   -3.1  26.4   200    6    3   7.1   3.9   10.7  51.3     5.5      M    M
  9500   -2.7  27.1   200    5    3   4.8   2.6   10.4  50.6     5.1      M    M
  9250   -2.3  27.9   200    4    2   5.4   3.0   10.0  50.0     4.8      M    M
  9000   -2.0  28.4   205    3    2   5.3   2.9    9.7  49.4     4.5      M    M
  8750   -1.6  29.1   200    3    1   4.8   2.6    9.3  48.7     4.1      M    M
  8500   -1.3  29.7   190    3    1   4.4   2.4    8.9  48.0     3.6      M    M
  8250   -1.1  30.0   175    3    1   4.8   2.6    8.5  47.3     3.2      M    M
  8000   -0.7  30.7   155    3    2   7.4   4.1    8.2  46.7     2.9      M    M
  7750   -0.1  31.8   130    5    2   6.1   3.3    8.0  46.5     2.7      M    M
  7500    0.2  32.4   125    5    3   3.3   1.8    7.6  45.6     2.3      M    M
  7250    0.5  32.9   115    6    3   4.2   2.3    7.1  44.8     1.9      M    M
  7000    0.9  33.6   110    8    4   3.9   2.1    6.7  44.1     1.5      M    M
  6750    1.2  34.2   100    9    5   5.2   2.8    6.3  43.3     1.2      M    M
  6500    1.7  35.1   095   10    5   6.7   3.7    6.0  42.8     0.9      M    M
  6250    2.2  36.0   095   10    5   7.6   4.2    5.8  42.4     0.7      M    M
  6000    2.8  37.0   095    8    4   8.2   4.5    5.7  42.2     0.5      M    M
  5750    3.4  38.1   100    7    4   8.2   4.5    5.6  42.0     0.4      M    M
  5500    4.0  39.2   105    5    3   8.6   4.7    5.5  41.8     0.2      M    M

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

           04/02/2015 at 0900 MDT          |       04/02/2015 at 1200 MDT
                                           |
K index... +21.5  LI... +272.2             | K index... +21.5  LI... +272.5
CAPE... +93.9  CIN... -50.1                | CAPE... +58.2  CIN... -50.6
                                           |
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 -54.6 -66.3  270  28 14   1.1   0.6 | -54.7 -66.5  260  33 17   1.8   1.0
 45000 -52.9 -63.2  270  41 21   1.2   0.7 | -52.1 -61.8  260  49 25   1.9   1.0
 40000 -53.7 -64.7  265  74 38  -0.7  -0.4 | -52.6 -62.7  265  74 38  -0.5  -0.3
 38000 -53.8 -64.8  265  85 44   0.8   0.4 | -52.7 -62.9  265  82 42   0.4   0.2
 36000 -53.3 -63.9  265  93 48   0.8   0.4 | -52.5 -62.5  265  86 44   0.4   0.2
 34000 -52.9 -63.2  260 100 52   1.3   0.7 | -52.3 -62.1  265  90 46   0.9   0.5
 32000 -50.8 -59.4  260  93 48   3.6   2.0 | -50.1 -58.2  265  86 44   3.8   2.1
 30000 -48.6 -55.5  260  85 44   4.3   2.4 | -47.8 -54.0  265  81 42   4.4   2.4
 29000 -46.9 -52.4  260  79 41   6.0   3.3 | -45.6 -50.1  260  77 40   6.3   3.5
 28000 -44.7 -48.5  260  72 37   6.0   3.3 | -43.7 -46.7  260  73 38   6.3   3.5
 27000 -42.9 -45.2  255  67 34   5.6   3.1 | -41.8 -43.2  260  70 36   6.3   3.4
 26000 -40.4 -40.7  255  64 33   9.2   5.1 | -39.7 -39.5  260  66 34   7.2   3.9
 25000 -37.6 -35.7  255  63 32   9.2   5.1 | -37.6 -35.7  260  63 32   7.2   4.0
 24000 -34.9 -30.8  255  62 32   9.4   5.1 | -35.4 -31.7  260  59 31   7.1   3.9
 23000 -32.5 -26.5  255  60 31   7.6   4.1 | -33.0 -27.4  255  56 29   8.6   4.7
 22000 -30.2 -22.4  255  57 29   7.6   4.1 | -30.4 -22.7  255  53 27   8.7   4.8
 21000 -28.0 -18.4  250  55 28   7.7   4.2 | -27.8 -18.0  255  51 26   8.7   4.8
 20000 -25.5 -13.9  250  52 27   8.5   4.6 | -25.3 -13.5  250  48 25   8.5   4.7
 19500 -24.2 -11.6  250  51 26   8.5   4.6 | -24.0 -11.2  250  46 24   8.5   4.7
 19000 -23.0  -9.4  255  49 25   8.5   4.7 | -22.8  -9.0  250  45 23   8.5   4.7
 18500 -21.7  -7.1  255  48 25   8.5   4.7 | -21.5  -6.7  245  43 22   8.6   4.7
 18000 -20.5  -4.9  255  47 24   8.5   4.7 | -20.2  -4.4  245  42 22   8.4   4.6
 17500 -19.2  -2.6  250  46 24   8.5   4.7 | -19.0  -2.2  245  41 21   8.4   4.6
 17000 -17.9  -0.2  250  46 23   9.3   5.1 | -17.7   0.1  245  39 20   8.4   4.6
 16500 -16.5   2.3  250  45 23   9.6   5.2 | -16.5   2.3  245  38 19   8.4   4.6
 16000 -15.1   4.8  250  45 23   9.4   5.2 | -15.3   4.5  245  36 18   8.3   4.6
 15500 -13.7   7.3  250  44 22   9.1   5.0 | -14.0   6.8  240  34 18   8.1   4.5
 15000 -11.7  10.9  245  42 22   8.6   4.7 | -12.2  10.0  240  32 16   8.3   4.6
 14500 -10.5  13.1  245  41 21   8.4   4.6 | -11.0  12.2  240  31 16   8.4   4.6
 14000  -9.2  15.4  240  39 20   7.9   4.3 |  -9.8  14.4  240  29 15   8.4   4.6
 13500  -8.2  17.2  235  36 19   7.0   3.8 |  -8.5  16.7  240  28 15   8.3   4.6
 13000  -7.2  19.0  230  34 17   6.5   3.6 |  -7.3  18.9  240  27 14   7.9   4.3
 12500  -6.5  20.3  225  30 16   4.7   2.6 |  -6.4  20.5  235  26 13   5.4   3.0
 12000  -5.8  21.6  215  27 14   4.7   2.6 |  -5.6  21.9  235  24 12   5.2   2.9
 11500  -5.2  22.6  210  25 13   4.1   2.3 |  -5.2  22.6  225  22 11   2.0   1.1
 11000  -4.7  23.5  205  22 11   4.2   2.3 |  -5.0  23.0  220  20 10   2.7   1.5
 10500  -4.1  24.6  200  20 10   4.6   2.5 |  -4.3  24.3  210  18  9   6.3   3.4
 10250  -3.7  25.3  195  19 10   3.6   2.0 |  -3.9  25.0  200  18  9   4.6   2.5
 10000  -3.4  25.9  195  17  9   7.1   3.9 |  -3.5  25.7  195  18  9  10.0   5.5
  9750  -2.8  27.0  190  15  8   8.1   4.5 |  -2.6  27.3  190  17  9  10.6   5.8
  9500  -2.4  27.7  190  14  7   5.2   2.9 |  -2.1  28.2  185  16  8   5.3   2.9
  9250  -1.9  28.6  185  12  6   6.3   3.5 |  -1.6  29.1  175  16  8   7.8   4.3
  9000  -1.5  29.3  185  11  6   4.9   2.7 |  -1.2  29.8  170  16  8   3.1   1.7
  8750  -1.2  29.8  180  10  5   3.5   1.9 |  -1.1  30.0  165  14  7  -0.3  -0.2
  8500  -1.0  30.2  180   9  5   3.6   2.0 |  -1.1  30.0  155  13  6   1.5   0.8
  8250  -0.7  30.7  175   9  4   3.4   1.9 |  -1.0  30.2  145  11  6   1.0   0.6
  8000  -0.5  31.1  170   8  4   2.4   1.3 |  -0.9  30.4  130  10  5   1.9   1.1
  7750  -0.3  31.5  165   8  4   2.4   1.3 |  -0.7  30.7  115   9  5   2.3   1.3
  7500  -0.1  31.8  165   8  4   2.6   1.5 |  -0.6  30.9  100   8  4   1.2   0.6
  7250   0.1  32.2  160   8  4   3.3   1.8 |  -0.4  31.3  085   8  4   4.0   2.2
  7000   0.4  32.7  155   7  4   4.1   2.3 |   0.0  32.0  070   8  4   7.9   4.4
  6750   0.7  33.3  150   6  3   4.8   2.6 |   0.6  33.1  055   8  4   8.3   4.6
  6500   1.2  34.2  130   4  2   6.7   3.7 |   1.3  34.3  050   8  4   8.6   4.7
  6250   1.8  35.2  115   4  2   9.5   5.2 |   1.9  35.4  045   9  4   9.7   5.3
  6000   2.6  36.7  110   4  2  11.3   6.2 |   2.7  36.9  040   8  4  10.6   5.8
  5750   3.3  37.9  110   3  2   9.3   5.1 |   3.5  38.3  040   8  4   9.4   5.2
  5500   4.0  39.2  105   3  2   8.5   4.7 |   4.2  39.6  035   8  4  11.7   6.4

           04/02/2015 at 1500 MDT          |       04/02/2015 at 1800 MDT
                                           |
K index... +26.5  LI... +272.4             | K index... +25.2  LI... +273.1
CAPE... +93.2  CIN... -27.5                | CAPE... +36.3  CIN... -28.5
                                           |
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 -55.4 -67.7  270  31 16   2.3   1.2 | -55.2 -67.4  275  35 18   2.9   1.6
 45000 -52.0 -61.6  260  44 22   2.4   1.3 | -50.7 -59.3  265  55 28   2.4   1.3
 40000 -51.8 -61.2  270  72 37   0.0   0.0 | -52.1 -61.8  270  79 40  -1.1  -0.6
 38000 -51.8 -61.2  270  82 42  -0.1  -0.0 | -52.5 -62.5  270  86 44   0.1   0.1
 36000 -51.8 -61.2  265  87 45  -0.1  -0.0 | -52.4 -62.3  270  89 46   0.1   0.1
 34000 -51.9 -61.4  265  93 48   0.2   0.1 | -52.4 -62.3  270  92 47   0.5   0.3
 32000 -49.9 -57.8  265  90 46   3.6   2.0 | -49.8 -57.6  270  90 46   4.7   2.6
 30000 -47.8 -54.0  265  86 44   4.0   2.2 | -46.6 -51.9  270  86 44   5.6   3.1
 29000 -45.5 -49.9  265  83 43   6.3   3.4 | -44.8 -48.6  265  83 43   5.9   3.2
 28000 -43.7 -46.7  265  81 42   6.3   3.4 | -43.1 -45.6  265  80 41   5.9   3.2
 27000 -41.8 -43.2  265  79 40   6.2   3.4 | -41.3 -42.3  265  77 40   5.9   3.2
 26000 -39.8 -39.6  265  75 39   6.9   3.8 | -39.4 -38.9  265  74 38   6.5   3.6
 25000 -37.8 -36.0  260  71 36   6.9   3.8 | -37.5 -35.5  265  71 36   6.5   3.6
 24000 -35.7 -32.3  260  67 34   6.8   3.7 | -35.6 -32.1  265  67 35   6.5   3.5
 23000 -33.3 -27.9  260  61 32   8.8   4.8 | -33.3 -27.9  260  62 32   8.1   4.4
 22000 -30.7 -23.3  255  55 28   8.9   4.9 | -30.9 -23.6  260  57 29   8.1   4.5
 21000 -28.0 -18.4  255  49 25   8.9   4.9 | -28.5 -19.3  255  51 26   8.2   4.5
 20000 -25.4 -13.7  250  46 23   8.9   4.9 | -25.9 -14.6  250  46 24   9.0   4.9
 19500 -24.1 -11.4  250  44 23   8.9   4.9 | -24.6 -12.3  250  44 23   9.0   5.0
 19000 -22.8  -9.0  250  42 22   8.9   4.9 | -23.2  -9.8  250  41 21   9.0   5.0
 18500 -21.5  -6.7  250  41 21   9.0   4.9 | -21.9  -7.4  250  39 20   9.1   5.0
 18000 -20.2  -4.4  250  39 20   8.1   4.4 | -20.6  -5.1  245  37 19   8.6   4.7
 17500 -19.0  -2.2  250  38 20   8.2   4.5 | -19.3  -2.7  250  35 18   8.6   4.7
 17000 -17.8  -0.0  250  37 19   7.9   4.3 | -18.1  -0.6  250  34 17   8.1   4.5
 16500 -16.7   1.9  250  37 19   7.8   4.3 | -16.9   1.6  250  32 17   7.8   4.3
 16000 -15.5   4.1  245  36 19   7.9   4.3 | -15.2   4.6  250  29 15   7.6   4.2
 15500 -13.7   7.3  245  35 18   8.3   4.6 | -14.1   6.6  250  27 14   7.5   4.1
 15000 -12.5   9.5  245  33 17   8.1   4.4 | -13.0   8.6  250  26 13   7.3   4.0
 14500 -11.3  11.7  245  32 17   7.9   4.3 | -12.0  10.4  255  23 12   7.0   3.9
 14000 -10.1  13.8  245  31 16   8.0   4.4 | -10.9  12.4  255  21 11   6.9   3.8
 13500  -9.0  15.8  245  29 15   8.2   4.5 | -10.0  14.0  255  19 10   6.5   3.6
 13000  -7.8  18.0  245  26 14   8.0   4.4 |  -9.0  15.8  260  17  9   6.4   3.5
 12500  -6.8  19.8  240  24 12   6.2   3.4 |  -8.1  17.4  260  14  7   5.8   3.2
 12000  -5.8  21.6  240  21 11   6.3   3.5 |  -7.3  18.9  265  12  6   5.9   3.2
 11500  -5.1  22.8  235  18  9   4.9   2.7 |  -6.4  20.5  270  10  5   6.3   3.5
 11000  -4.4  24.1  235  15  8   5.1   2.8 |  -5.5  22.1  275   8  4   6.1   3.3
 10500  -3.7  25.3  225  13  6   5.5   3.0 |  -4.7  23.5  285   7  4   4.7   2.6
 10250  -3.3  26.1  220  11  6   4.7   2.6 |  -4.4  24.1  290   7  3   4.6   2.5
 10000  -2.9  26.8  210  10  5   7.7   4.2 |  -4.1  24.6  300   6  3   5.5   3.0
  9750  -2.3  27.9  195   9  5   6.8   3.7 |  -3.7  25.3  320   6  3   4.1   2.2
  9500  -2.0  28.4  180   7  4   2.9   1.6 |  -3.5  25.7  330   7  4   2.1   1.2
  9250  -1.7  28.9  165   7  3   4.2   2.3 |  -3.3  26.1  340   8  4   2.6   1.5
  9000  -1.5  29.3  145   7  3   2.6   1.4 |  -3.1  26.4  350   9  5   2.5   1.4
  8750  -1.4  29.5  125   6  3   0.8   0.4 |  -2.9  26.8  360  10  5   2.1   1.2
  8500  -1.3  29.7  105   6  3   0.9   0.5 |  -2.8  27.0  360  11  6   1.8   1.0
  8250  -1.2  29.8  085   7  3   0.8   0.5 |  -2.6  27.3  005  13  7   2.1   1.2
  8000  -1.2  29.8  070   8  4   1.1   0.6 |  -2.4  27.7  010  14  7   3.2   1.8
  7750  -1.1  30.0  055   9  5   0.8   0.5 |  -2.2  28.0  015  16  8   5.2   2.9
  7500  -1.0  30.2  045  10  5  -0.1  -0.1 |  -1.7  28.9  015  17  9   5.7   3.1
  7250  -1.0  30.2  035  11  6   1.6   0.9 |  -1.3  29.7  015  19 10   6.6   3.6
  7000  -0.8  30.6  030  12  6   4.1   2.3 |  -0.8  30.6  010  19 10   8.0   4.4
  6750  -0.5  31.1  020  13  6   5.2   2.8 |  -0.2  31.6  010  19 10   7.8   4.3
  6500  -0.0  32.0  015  13  7   6.0   3.3 |   0.4  32.7  005  18  9   8.4   4.6
  6250   0.5  32.9  010  13  7   9.1   5.0 |   1.0  33.8  005  17  9   9.9   5.4
  6000   1.3  34.3  005  12  6  11.7   6.4 |   1.8  35.2  360  16  8  10.6   5.8
  5750   2.1  35.8  005  11  6   9.8   5.3 |   2.5  36.5  360  15  8  10.1   5.6
  5500   2.8  37.0  360  10  5  12.0   6.6 |   3.3  37.9  360  14  7  12.2   6.7
________________________________________________________________________________

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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