Soaring Guidance
Issued by NWS Denver/Boulder, CO

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268
UXUS97 KBOU 270112
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1812 MST Sunday, February 26, 2017

This forecast is for Monday, February 27, 2017:

If the trigger temperature of 42.1 F/5.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 621 ft/min (3.2 m/s)
   Maximum height of thermals.................. 13336 ft MSL (8029 ft AGL)

Forecast maximum temperature................... 51.0 F/11.0 C
Time of trigger temperature.................... 1030 MST
Time of overdevelopment........................ 1700 MST
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10603 ft MSL (5296 ft AGL)
Thermal soaring outlook for Tuesday 02/28...... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 43709 ft MSL (38402 ft AGL)
Wave soaring outlook for Tuesday 02/28......... Poor

Remarks...

Sunrise/Sunset.................... 06:34:55 / 17:48:32 MST
Total possible sunshine........... 11 hr 13 min 37 sec (673 min 37 sec)
Altitude of sun at 12:11:59 MST... 42.21 degrees

Upper air data from numerical model forecast valid on 02/27/2017 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 16477 ft MSL (11170 ft AGL)
Lifted condensation level....... 15127 ft MSL (9821 ft AGL)
Lifted index.................... +5.1
K index......................... +0.8

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  -56.3 -69.3   255   39   20  -0.4  -0.2      M     M       M      M    M
 45000  -56.9 -70.4   255   61   31  -0.4  -0.2      M     M       M      M    M
 40000  -59.7 -75.5   255   65   34  -2.2  -1.2      M     M       M      M    M
 38000  -61.0 -77.8   250   65   34  -1.3  -0.7      M     M       M      M    M
 36000  -60.2 -76.4   250   64   33   1.6   0.9      M     M       M      M    M
 34000  -59.2 -74.6   250   63   32   1.6   0.9      M     M       M      M    M
 32000  -55.8 -68.4   255   61   32   6.7   3.7      M     M       M      M    M
 30000  -51.8 -61.2   255   61   31   6.5   3.6      M     M       M      M    M
 29000  -49.3 -56.7   255   60   31   8.9   4.9   23.1  73.5     9.5      M    M
 28000  -46.7 -52.1   255   59   31   8.9   4.9   22.7  72.8     9.3      M    M
 27000  -44.0 -47.2   255   59   30   8.9   4.9   22.4  72.3     9.2      M    M
 26000  -41.4 -42.5   260   58   30   8.2   4.5   22.1  71.7     9.0      M    M
 25000  -38.9 -38.0   260   57   29   8.3   4.5   21.4  70.5     8.6      M    M
 24000  -36.5 -33.7   260   55   29   8.3   4.5   20.9  69.6     8.3      M    M
 23000  -34.0 -29.2   260   54   28   7.2   4.0   20.3  68.6     7.9      M    M
 22000  -31.9 -25.4   260   51   26   7.2   4.0   19.3  66.8     7.2      M    M
 21000  -29.7 -21.5   260   48   25   7.3   4.0   18.4  65.2     6.6      M    M
 20000  -27.4 -17.3   255   45   23   8.3   4.5   17.7  63.9     6.0      M    M
 19500  -26.2 -15.2   255   43   22   8.3   4.5   17.4  63.4     5.8      M    M
 19000  -24.9 -12.8   250   41   21   8.3   4.5   17.2  62.9     5.6      M    M
 18500  -23.7 -10.7   250   39   20   8.2   4.5   16.9  62.4     5.4      M    M
 18000  -22.5  -8.5   245   38   19   8.0   4.4   16.7  62.1     5.3      M    M
 17500  -21.4  -6.5   245   35   18   6.5   3.6   16.2  61.2     4.9      M    M
 17000  -20.4  -4.7   240   33   17   6.8   3.7   15.7  60.2     4.5      M    M
 16500  -19.2  -2.6   240   28   15   4.5   2.5   14.6  58.2     3.5      M    M
 16000  -18.5  -1.3   240   25   13   4.5   2.5   13.7  56.7     2.7      M    M
 15500  -17.8  -0.0   240   22   11   5.0   2.8   12.9  55.2     2.0      M    M
 15000  -17.1   1.2   245   19   10   4.8   2.6   12.1  53.7     1.3      M    M
 14500  -16.2   2.8   250   17    9   7.6   4.2   11.4  52.6     0.7      M    M
 14000  -15.0   5.0   255   18    9   7.9   4.3   11.1  52.0     0.4      M    M
 13500  -13.9   7.0   260   20   10   7.3   4.0   10.8  51.5     0.1      M    M
 13000  -12.9   8.8   265   23   12   7.1   3.9   10.4  50.7    -0.3    583  3.0
 12500  -11.8  10.8   265   26   13   6.7   3.7    9.9  49.9    -0.8    538  2.7
 12000  -10.9  12.4   270   28   14   6.5   3.6    9.4  48.9    -1.3    494  2.5
 11500   -9.9  14.2   270   30   16   5.9   3.2    8.9  48.0    -1.8    451  2.3
 11000   -9.1  15.6   270   30   15   5.5   3.0    8.2  46.7    -2.5    413  2.1
 10500   -8.3  17.1   270   29   15   5.2   2.9    7.5  45.5    -3.2    374  1.9
 10250   -8.0  17.6   270   27   14   4.8   2.6    7.1  44.8    -3.5    355  1.8
 10000   -7.6  18.3   265   25   13   5.6   3.1    6.7  44.1    -3.9    337  1.7
  9750   -7.1  19.2   265   23   12   6.4   3.5    6.5  43.6    -4.2    316  1.6
  9500   -6.7  19.9   265   20   10   5.8   3.2    6.2  43.1    -4.5    294  1.5
  9250   -6.2  20.8   260   18    9   5.8   3.2    5.9  42.6    -4.8    274  1.4
  9000   -5.8  21.6   260   15    8   5.4   3.0    5.5  42.0    -5.1    254  1.3
  8750   -5.4  22.3   255   13    7   5.2   2.9    5.2  41.4    -5.5    235  1.2
  8500   -5.0  23.0   250   11    6   5.7   3.2    4.9  40.7    -5.8    215  1.1
  8250   -4.6  23.7   240    9    5   5.5   3.0    4.5  40.2    -6.1    194  1.0
  8000   -4.1  24.6   230    8    4   6.4   3.5    4.2  39.6    -6.4    174  0.9
  7750   -3.6  25.5   210    7    4   6.5   3.5    4.0  39.2    -6.6    151  0.8
  7500   -3.2  26.2   200    7    4   5.7   3.1    3.7  38.7    -7.1    130  0.7
  7250   -2.7  27.1   190    7    4   5.7   3.1    3.4  38.1    -7.3    110  0.6
  7000   -2.3  27.9   180    8    4   6.7   3.7    3.1  37.6    -7.6     89  0.5
  6750   -1.7  28.9   175    9    4   6.4   3.5    2.9  37.3    -7.8     66  0.3
  6500   -1.3  29.7   175    9    5   7.0   3.9    2.6  36.7    -8.1     45  0.2
  6250   -0.9  30.4   170   10    5   1.1   0.6    2.3  36.2    -8.4     24  0.1
  6000   -1.3  29.7   175   11    6 -12.0  -6.6    1.1  34.0    -9.6     31  0.2
  5750   -2.7  27.1   185   12    6 -24.6 -13.5   -0.9  30.3   -11.7     63  0.3
  5500   -5.0  23.0   190   10    5 -34.9 -19.2   -4.0  24.8   -14.8    126  0.6

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

           02/27/2017 at 0800 MST          |       02/27/2017 at 1100 MST
                                           |
K index... -1.1  LI... +5.7                | K index... -4.9  LI... +4.7
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.6
                                           |
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  255  37 19  -0.9  -0.5 | -55.7 -68.3  260  36 19  -1.0  -0.5
 45000 -56.0 -68.8  260  72 37  -0.9  -0.5 | -57.1 -70.8  260  72 37  -1.0  -0.5
 40000 -59.4 -74.9  260  75 38  -2.6  -1.4 | -59.6 -75.3  260  74 38  -1.9  -1.0
 38000 -60.9 -77.6  260  72 37  -2.3  -1.3 | -60.7 -77.3  260  70 36  -1.0  -0.6
 36000 -60.6 -77.1  260  68 35   0.8   0.4 | -59.7 -75.5  260  71 36   2.0   1.1
 34000 -60.1 -76.2  260  64 33   1.0   0.5 | -58.4 -73.1  260  71 37   2.1   1.1
 32000 -57.1 -70.8  260  61 32   6.5   3.6 | -55.2 -67.4  260  74 38   6.3   3.4
 30000 -53.2 -63.8  260  58 30   6.3   3.5 | -51.5 -60.7  260  78 40   6.2   3.4
 29000 -50.8 -59.4  260  56 29   9.1   5.0 | -49.3 -56.7  260  78 40   7.9   4.3
 28000 -48.0 -54.4  255  54 28   9.2   5.0 | -46.9 -52.4  260  76 39   7.9   4.3
 27000 -45.3 -49.5  255  51 26   9.2   5.0 | -44.5 -48.1  260  75 38   7.9   4.3
 26000 -42.5 -44.5  255  50 26   8.6   4.7 | -42.2 -44.0  260  72 37   8.0   4.4
 25000 -39.9 -39.8  255  51 26   8.7   4.8 | -39.8 -39.6  260  66 34   8.0   4.4
 24000 -37.3 -35.1  260  53 27   8.7   4.8 | -37.4 -35.3  260  60 31   8.0   4.4
 23000 -34.8 -30.6  260  53 27   8.4   4.6 | -34.9 -30.8  255  56 29   8.9   4.9
 22000 -32.2 -26.0  260  51 26   8.4   4.6 | -32.3 -26.1  255  54 28   8.9   4.9
 21000 -29.7 -21.5  260  49 25   8.4   4.6 | -29.6 -21.3  255  53 27   8.9   4.9
 20000 -27.2 -17.0  260  46 24   8.6   4.7 | -27.0 -16.6  255  51 26   8.0   4.4
 19500 -25.9 -14.6  255  45 23   8.6   4.7 | -25.8 -14.4  255  50 26   8.0   4.4
 19000 -24.6 -12.3  255  43 22   8.6   4.7 | -24.6 -12.3  250  48 25   8.0   4.4
 18500 -23.3  -9.9  255  42 22   8.6   4.7 | -23.4 -10.1  250  47 24   8.0   4.4
 18000 -22.0  -7.6  255  41 21   8.5   4.7 | -22.2  -8.0  250  46 24   8.1   4.5
 17500 -20.7  -5.3  255  39 20   8.3   4.5 | -20.3  -4.5  245  44 23   8.5   4.7
 17000 -18.9  -2.0  250  36 19   7.7   4.2 | -19.0  -2.2  245  43 22   8.6   4.7
 16500 -17.9  -0.2  250  36 18   6.6   3.6 | -17.7   0.1  240  42 21   8.8   4.8
 16000 -16.9   1.6  250  35 18   6.6   3.6 | -16.4   2.5  240  40 21   8.8   4.8
 15500 -16.0   3.2  250  34 17   5.9   3.2 | -15.2   4.6  235  39 20   7.7   4.2
 15000 -15.1   4.8  250  33 17   6.0   3.3 | -14.0   6.8  235  39 20   7.9   4.3
 14500 -14.3   6.3  255  32 17   4.8   2.7 | -13.0   8.6  240  39 20   6.0   3.3
 14000 -13.6   7.5  255  33 17   4.8   2.6 | -12.1  10.2  245  40 20   5.8   3.2
 13500 -12.9   8.8  260  33 17   4.6   2.5 | -11.3  11.7  250  40 21   3.6   2.0
 13000 -12.2  10.0  260  34 17   4.6   2.5 | -11.0  12.2  250  38 20   2.8   1.5
 12500 -11.6  11.1  265  34 17   4.7   2.6 | -10.6  12.9  255  36 19   3.2   1.8
 12000 -10.9  12.4  265  31 16   4.8   2.6 | -10.1  13.8  255  32 16   3.7   2.0
 11500 -10.2  13.6  265  29 15   6.6   3.6 |  -9.6  14.7  260  27 14   6.1   3.3
 11000  -9.0  15.8  270  26 13   7.7   4.2 |  -8.4  16.9  255  22 11   8.0   4.4
 10500  -7.9  17.8  270  22 11   7.2   4.0 |  -7.2  19.0  255  17  9   7.1   3.9
 10250  -7.4  18.7  270  20 10   6.7   3.7 |  -6.7  19.9  250  15  8   6.4   3.5
 10000  -6.9  19.6  270  18  9   7.5   4.1 |  -6.2  20.8  250  13  7   6.2   3.4
  9750  -6.3  20.7  270  16  8   7.9   4.3 |  -5.8  21.6  245  11  6   6.0   3.3
  9500  -5.7  21.7  270  14  7   6.8   3.7 |  -5.3  22.5  240  10  5   7.3   4.0
  9250  -5.2  22.6  265  12  6   6.5   3.6 |  -4.7  23.5  230   8  4   8.2   4.5
  9000  -4.8  23.4  265  10  5   6.1   3.4 |  -4.1  24.6  225   7  4   7.0   3.8
  8750  -4.3  24.3  260   8  4   6.0   3.3 |  -3.6  25.5  215   7  3   6.5   3.6
  8500  -3.8  25.2  250   7  4   6.7   3.7 |  -3.1  26.4  210   7  3   7.6   4.2
  8250  -3.3  26.1  240   6  3   6.6   3.6 |  -2.5  27.5  205   7  3   8.4   4.6
  8000  -2.8  27.0  225   5  2   7.3   4.0 |  -1.9  28.6  200   7  3   6.5   3.6
  7750  -2.3  27.9  205   5  2   7.1   3.9 |  -1.5  29.3  195   7  3   5.9   3.2
  7500  -1.8  28.8  195   5  3   6.3   3.5 |  -1.0  30.2  195   7  4   7.2   4.0
  7250  -1.3  29.7  185   6  3   6.6   3.6 |  -0.5  31.1  190   7  4   6.8   3.7
  7000  -0.8  30.6  175   7  4   6.3   3.5 |   0.0  32.0  190   8  4   7.1   3.9
  6750  -0.4  31.3  175   8  4   4.3   2.4 |   0.6  33.1  190   8  4   7.8   4.3
  6500  -0.1  31.8  180   9  5   4.0   2.2 |   1.2  34.2  190   7  4   8.1   4.5
  6250   0.1  32.2  180  11  6   1.2   0.6 |   1.8  35.2  190   7  4   8.4   4.6
  6000  -0.2  31.6  185  12  6 -11.3  -6.2 |   2.4  36.3  195   7  3   8.5   4.7
  5750  -1.4  29.5  190  13  7 -18.7 -10.3 |   3.2  37.8  195   6  3  13.6   7.5
  5500  -2.7  27.1  190   9  5 -14.6  -8.0 |   4.5  40.1  195   6  3  23.0  12.6

           02/27/2017 at 1400 MST          |       02/27/2017 at 1700 MST
                                           |
K index... -1.8  LI... +3.3                | K index... +3.3  LI... +2.8
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... -1.0
                                           |
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 -56.5 -69.7  250  39 20  -1.3  -0.7 | -56.0 -68.8  255  43 22  -0.6  -0.3
 45000 -58.5 -73.3  255  66 34  -1.3  -0.7 | -56.8 -70.2  255  65 33  -0.6  -0.3
 40000 -58.8 -73.8  260  77 40   0.1   0.0 | -57.3 -71.1  260  78 40  -0.3  -0.2
 38000 -58.8 -73.8  260  79 41   0.1   0.0 | -57.5 -71.5  260  82 42  -0.3  -0.1
 36000 -58.7 -73.7  260  93 48   0.2   0.1 | -57.7 -71.9  265 106 55  -0.2  -0.1
 34000 -58.6 -73.5  260 108 56   0.3   0.2 | -57.8 -72.0  265 129 66  -0.1  -0.0
 32000 -55.3 -67.5  260 112 58   7.1   3.9 | -54.2 -65.6  265 133 69   7.9   4.3
 30000 -51.0 -59.8  260 114 59   7.1   3.9 | -49.5 -57.1  265 132 68   7.9   4.3
 29000 -48.7 -55.7  260 108 56   7.7   4.2 | -47.3 -53.1  265 121 62   7.0   3.8
 28000 -46.4 -51.5  260 100 51   7.7   4.2 | -45.2 -49.4  265 104 54   6.9   3.8
 27000 -44.1 -47.4  260  92 47   7.7   4.2 | -43.1 -45.6  260  88 45   6.9   3.8
 26000 -41.7 -43.1  255  83 43   8.7   4.8 | -41.0 -41.8  255  74 38   7.1   3.9
 25000 -39.1 -38.4  255  73 38   8.6   4.7 | -38.9 -38.0  255  70 36   7.1   3.9
 24000 -36.6 -33.9  250  63 33   8.6   4.7 | -36.8 -34.2  260  66 34   7.1   3.9
 23000 -34.0 -29.2  245  56 29   7.9   4.3 | -34.6 -30.3  260  62 32   7.8   4.3
 22000 -31.6 -24.9  250  54 28   7.9   4.3 | -32.2 -26.0  255  54 28   7.9   4.4
 21000 -29.3 -20.7  255  53 27   7.9   4.3 | -29.9 -21.8  250  47 24   8.0   4.4
 20000 -26.9 -16.4  255  52 27   8.1   4.4 | -27.4 -17.3  250  44 23   8.6   4.7
 19500 -25.7 -14.3  255  51 26   8.1   4.4 | -26.1 -15.0  255  47 24   8.5   4.7
 19000 -24.5 -12.1  255  51 26   8.1   4.4 | -24.8 -12.6  255  51 26   8.5   4.7
 18500 -23.2  -9.8  255  50 26   8.1   4.4 | -22.9  -9.2  260  55 29   8.5   4.7
 18000 -21.4  -6.5  255  49 25   8.2   4.5 | -21.7  -7.1  260  58 30   7.9   4.3
 17500 -20.2  -4.4  255  46 24   8.2   4.5 | -20.5  -4.9  260  59 31   7.7   4.2
 17000 -18.9  -2.0  250  43 22   8.3   4.5 | -19.3  -2.7  265  60 31   7.4   4.1
 16500 -17.7   0.1  250  43 22   8.5   4.7 | -18.3  -0.9  265  59 31   6.4   3.5
 16000 -16.4   2.5  250  43 22   8.7   4.8 | -17.4   0.7  265  58 30   6.6   3.6
 15500 -15.3   4.5  250  43 22   6.5   3.5 | -16.5   2.3  265  56 29   4.6   2.5
 15000 -14.3   6.3  250  44 23   6.9   3.8 | -15.8   3.6  265  54 28   4.8   2.6
 14500 -13.5   7.7  255  44 23   3.0   1.6 | -15.2   4.6  265  51 26   4.4   2.4
 14000 -13.2   8.2  255  42 22   2.4   1.3 | -14.6   5.7  260  46 24   4.3   2.4
 13500 -12.8   9.0  255  40 21   5.0   2.8 | -13.9   7.0  260  42 22   7.0   3.8
 13000 -11.9  10.6  255  35 18   6.4   3.5 | -12.6   9.3  260  40 21   8.6   4.7
 12500 -10.9  12.4  255  31 16   8.2   4.5 | -11.3  11.7  260  38 19   9.0   5.0
 12000  -9.5  14.9  255  30 15   9.5   5.2 |  -9.9  14.2  255  35 18   9.3   5.1
 11500  -8.0  17.6  255  28 14   9.3   5.1 |  -8.5  16.7  255  33 17   9.3   5.1
 11000  -6.7  19.9  250  25 13   9.0   4.9 |  -7.2  19.0  255  31 16   9.2   5.0
 10500  -5.4  22.3  250  22 11   8.6   4.7 |  -5.8  21.6  250  30 16   9.6   5.3
 10250  -4.8  23.4  250  21 11   8.2   4.5 |  -5.1  22.8  250  30 15  10.1   5.5
 10000  -4.2  24.4  245  19 10   8.1   4.4 |  -4.3  24.3  250  29 15   9.6   5.2
  9750  -3.6  25.5  245  18  9   8.0   4.4 |  -3.6  25.5  250  29 15   9.4   5.2
  9500  -3.0  26.6  245  17  9   8.1   4.4 |  -2.9  26.8  250  28 15   9.9   5.4
  9250  -2.4  27.7  240  16  8   8.5   4.7 |  -2.1  28.2  245  28 14  10.6   5.8
  9000  -1.7  28.9  235  14  7   7.0   3.9 |  -1.4  29.5  245  27 14   9.1   5.0
  8750  -1.3  29.7  235  13  7   6.1   3.3 |  -0.8  30.6  245  26 14   8.3   4.6
  8500  -0.8  30.6  230  12  6   7.4   4.1 |  -0.1  31.8  245  26 13   9.6   5.3
  8250  -0.2  31.6  230  11  5   8.6   4.7 |   0.7  33.3  245  25 13  10.8   5.9
  8000   0.4  32.7  225   9  5   5.7   3.1 |   1.4  34.5  245  24 12   7.8   4.3
  7750   0.7  33.3  220   8  4   6.6   3.6 |   1.9  35.4  240  23 12   6.6   3.6
  7500   1.4  34.5  220   7  4  10.0   5.5 |   2.5  36.5  240  21 11   8.9   4.9
  7250   2.1  35.8  220   7  4   9.2   5.0 |   3.1  37.6  240  20 10   8.3   4.6
  7000   2.8  37.0  225   7  4   9.3   5.1 |   3.8  38.8  235  19 10   9.0   5.0
  6750   3.5  38.3  225   7  4   9.8   5.4 |   4.4  39.9  235  18  9   8.6   4.7
  6500   4.2  39.6  225   7  4  10.3   5.6 |   5.0  41.0  235  16  8   7.8   4.3
  6250   5.0  41.0  225   7  3  10.6   5.8 |   5.6  42.1  235  15  8   8.0   4.4
  6000   5.8  42.4  225   7  3   8.6   4.7 |   6.2  43.2  235  13  7   8.0   4.4
  5750   6.4  43.5  225   6  3  12.6   6.9 |   6.8  44.2  235  11  6   8.7   4.8
  5500   7.8  46.0  230   6  3  24.9  13.7 |   7.4  45.3  235   9  5   9.8   5.4
________________________________________________________________________________

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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