Soaring Guidance
Issued by NWS Denver/Boulder, CO

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951
UXUS97 KBOU 210156
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1856 MST Friday, January 20, 2017

This forecast is for Saturday, January 21, 2017:

If the trigger temperature of 44.7 F/7.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7772 ft MSL (2443 ft AGL)

Forecast maximum temperature................... 42.0 F/6.0 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 1500 MST
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6399 ft MSL (1070 ft AGL)
Thermal soaring outlook for Sunday 01/22....... 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)................ Neither
Potential height of wave....................... 52962 ft MSL (47633 ft AGL)
Wave soaring outlook for Sunday 01/22.......... Poor

Remarks...

Sunrise/Sunset.................... 07:15:34 / 17:06:18 MST
Total possible sunshine........... 9 hr 50 min 44 sec (590 min 44 sec)
Altitude of sun at 12:10:56 MST... 30.45 degrees

Upper air data from numerical model forecast valid on 01/21/2017 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 14033 ft MSL (8704 ft AGL)
Lifted condensation level....... 11954 ft MSL (6625 ft AGL)
Lifted index.................... +6.4
K index......................... +11.6

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  -52.7 -62.9   240   14    7   2.5   1.4      M     M       M      M    M
 45000  -48.9 -56.0   240   15    8   2.5   1.4      M     M       M      M    M
 40000  -46.1 -51.0   250   14    7   1.7   0.9      M     M       M      M    M
 38000  -45.2 -49.4   255   13    7  -0.9  -0.5      M     M       M      M    M
 36000  -46.3 -51.3   245   15    8  -1.9  -1.0      M     M       M      M    M
 34000  -47.4 -53.3   240   17    8  -1.9  -1.0      M     M       M      M    M
 32000  -48.8 -55.8   240   17    9  -2.5  -1.4      M     M       M      M    M
 30000  -50.5 -58.9   245   16    8  -2.3  -1.3      M     M       M      M    M
 29000  -50.0 -58.0   245   16    8   7.4   4.1   22.1  71.9    12.5      M    M
 28000  -47.8 -54.0   245   17    9   7.3   4.0   21.0  69.9    11.9      M    M
 27000  -45.7 -50.3   245   17    9   7.3   4.0   20.1  68.2    11.3      M    M
 26000  -43.5 -46.3   245   18    9   8.3   4.6   19.3  66.8    10.8      M    M
 25000  -40.7 -41.3   245   17    9   9.2   5.1   19.0  66.2    10.7      M    M
 24000  -38.0 -36.4   240   16    8   9.2   5.1   18.8  65.8    10.6      M    M
 23000  -35.2 -31.4   240   16    8   9.0   4.9   18.7  65.7    10.7      M    M
 22000  -32.6 -26.7   240   15    8   8.7   4.8   18.2  64.8    10.4      M    M
 21000  -30.0 -22.0   240   14    7   8.7   4.8   17.9  64.2    10.2      M    M
 20000  -27.5 -17.5   245   14    7   7.6   4.2   17.5  63.5    10.0      M    M
 19500  -26.4 -15.5   245   13    7   7.5   4.1   17.1  62.7     9.7      M    M
 19000  -25.3 -13.5   245   12    6   7.5   4.1   16.7  62.0     9.4      M    M
 18500  -24.1 -11.4   245   11    6   7.6   4.1   16.3  61.3     9.1      M    M
 18000  -23.0  -9.4   245   10    5   7.6   4.2   15.9  60.7     8.9      M    M
 17500  -22.0  -7.6   245    9    5   6.3   3.5   15.5  60.0     8.5      M    M
 17000  -21.1  -6.0   245    9    4   6.1   3.3   14.9  58.8     8.0      M    M
 16500  -19.7  -3.5   245    7    4   5.9   3.3   13.9  57.1     7.2      M    M
 16000  -18.9  -2.0   245    7    3   5.9   3.3   13.3  55.9     6.7      M    M
 15500  -18.0  -0.4   245    6    3   6.4   3.5   12.7  54.8     6.2      M    M
 15000  -17.0   1.4   245    5    3   6.9   3.8   12.2  53.9     5.7      M    M
 14500  -15.9   3.4   240    5    2   6.9   3.8   11.7  53.1     5.4      M    M
 14000  -14.9   5.2   240    4    2   7.0   3.8   11.2  52.2     4.9      M    M
 13500  -13.9   7.0   240    3    2   7.0   3.8   10.8  51.4     4.6      M    M
 13000  -12.8   9.0   235    2    1   7.3   4.0   10.4  50.7     4.2      M    M
 12500  -11.7  10.9   220    1    1   7.3   4.0   10.0  49.9     3.8      M    M
 12000  -10.6  12.9   185    1    1   7.1   3.9    9.6  49.2     3.5      M    M
 11500   -9.6  14.7   155    2    1   7.1   3.9    9.1  48.5     3.1      M    M
 11000   -8.5  16.7   145    2    1   7.3   4.0    8.7  47.7     2.7      M    M
 10500   -7.4  18.7   145    3    2   7.4   4.0    8.3  47.0     2.4      M    M
 10250   -6.9  19.6   145    4    2   6.3   3.4    8.1  46.7     2.2      M    M
 10000   -6.5  20.3   145    4    2   6.7   3.7    7.8  46.1     1.9      M    M
  9750   -5.9  21.4   150    4    2   7.9   4.3    7.7  45.8     1.7      M    M
  9500   -5.3  22.5   155    5    2   7.5   4.1    7.5  45.5     1.6      M    M
  9250   -4.8  23.4   155    5    3   7.1   3.9    7.3  45.2     1.4      M    M
  9000   -4.3  24.3   160    5    3   6.9   3.8    7.1  44.8     1.2      M    M
  8750   -3.7  25.3   160    5    3   7.2   3.9    6.9  44.4     1.0      M    M
  8500   -3.2  26.2   160    5    3   7.0   3.8    6.7  44.1     0.8      M    M
  8250   -2.7  27.1   160    5    2   6.6   3.6    6.5  43.6     0.5      M    M
  8000   -2.2  28.0   160    4    2   6.5   3.6    6.2  43.2     0.3      M    M
  7750   -1.8  28.8   160    4    2   5.4   3.0    5.9  42.7     0.0      M    M
  7500   -1.5  29.3   160    3    2   4.2   2.3    5.5  42.0    -0.4    122  0.6
  7250   -1.2  29.8   155    2    1   3.9   2.1    5.1  41.2    -0.8    106  0.5
  7000   -0.9  30.4   150    2    1   4.6   2.5    4.7  40.4    -1.3     90  0.5
  6750   -0.6  30.9   135    1    0   1.7   0.9    4.2  39.6    -1.7     74  0.4
  6500   -0.6  30.9   145    1    0  -1.4  -0.8    3.4  38.2    -2.5     68  0.3
  6250   -0.7  30.7   000    0    0  -0.7  -0.4    2.6  36.7    -3.3     62  0.3
  6000   -0.8  30.6   245    1    0  -1.4  -0.8    1.8  35.3    -4.1     57  0.3
  5750   -1.2  29.8   245    1    1 -14.1  -7.7    0.6  33.2    -5.3     63  0.3
  5500   -3.1  26.4   225    1    1 -33.3 -18.3   -1.9  28.5    -7.9    111  0.6

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

           01/21/2017 at 0800 MST          |       01/21/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +3.4        | CAPE...     0.0    LI...       +3.6
CINH...    -0.6    K Index... +12.7        | CINH...     0.0    K Index... +14.1
                                           |
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 -52.5 -62.5  255  15  8   2.6   1.4 | -52.3 -62.1  250  18  9   2.8   1.5
 45000 -48.6 -55.5  250  17  9   2.6   1.4 | -47.9 -54.2  245  20 11   2.8   1.5
 40000 -45.7 -50.3  250  15  8   1.7   1.0 | -45.1 -49.2  215  28 15   1.7   1.0
 38000 -44.7 -48.5  250  14  7  -0.5  -0.3 | -44.1 -47.4  210  33 17  -0.0  -0.0
 36000 -45.7 -50.3  245  13  7  -1.6  -0.9 | -44.7 -48.5  200  43 22  -1.0  -0.6
 34000 -46.6 -51.9  240  14  7  -1.6  -0.9 | -45.3 -49.5  195  54 28  -1.0  -0.6
 32000 -48.1 -54.6  240  13  7  -3.0  -1.6 | -47.0 -52.6  190  70 36  -3.6  -2.0
 30000 -50.1 -58.2  235  12  6  -2.9  -1.6 | -49.2 -56.6  185  88 45  -3.5  -1.9
 29000 -49.9 -57.8  235  12  6   7.0   3.9 | -49.4 -56.9  185  92 47   5.6   3.1
 28000 -48.0 -54.4  235  12  6   6.5   3.6 | -48.0 -54.4  185  84 43   4.8   2.7
 27000 -46.1 -51.0  235  12  6   6.5   3.6 | -46.5 -51.7  185  76 39   4.9   2.7
 26000 -44.1 -47.4  240  12  6   7.8   4.3 | -45.1 -49.2  185  68 35   6.5   3.6
 25000 -41.3 -42.3  240  11  6   9.5   5.2 | -42.2 -44.0  185  67 35   9.8   5.4
 24000 -38.5 -37.3  240  11  6   9.5   5.2 | -39.3 -38.7  185  66 34   9.8   5.4
 23000 -35.6 -32.1  240  10  5   9.2   5.1 | -36.3 -33.3  185  65 34   9.7   5.3
 22000 -33.0 -27.4  240  10  5   8.7   4.8 | -33.6 -28.5  185  67 35   9.2   5.0
 21000 -30.4 -22.7  235  10  5   8.7   4.8 | -30.8 -23.4  185  70 36   9.2   5.1
 20000 -27.9 -18.2  235   9  5   8.1   4.4 | -28.1 -18.6  185  71 37   8.6   4.7
 19500 -26.7 -16.1  230   9  5   8.0   4.4 | -26.8 -16.2  185  69 36   8.5   4.6
 19000 -25.5 -13.9  230   9  5   8.0   4.4 | -25.6 -14.1  185  67 35   8.5   4.6
 18500 -24.3 -11.7  230   9  4   8.0   4.4 | -24.3 -11.7  185  65 33   8.5   4.7
 18000 -23.2  -9.8  225   8  4   8.0   4.4 | -23.1  -9.6  185  63 32   8.5   4.7
 17500 -22.0  -7.6  225   8  4   7.3   4.0 | -21.3  -6.3  185  58 30   7.4   4.1
 17000 -20.4  -4.7  225   7  4   7.1   3.9 | -20.2  -4.4  185  53 27   7.5   4.1
 16500 -19.4  -2.9  220   6  3   6.5   3.6 | -19.1  -2.4  185  47 24   7.3   4.0
 16000 -18.5  -1.3  220   6  3   6.4   3.5 | -18.0  -0.4  185  38 20   7.3   4.0
 15500 -17.5   0.5  215   5  3   6.2   3.4 | -16.9   1.6  190  29 15   7.2   3.9
 15000 -16.6   2.1  210   5  2   6.0   3.3 | -15.9   3.4  190  27 14   7.0   3.8
 14500 -15.7   3.7  200   4  2   6.1   3.3 | -14.8   5.4  190  25 13   7.0   3.9
 14000 -14.8   5.4  185   4  2   6.6   3.6 | -13.8   7.2  190  24 12   7.2   4.0
 13500 -13.8   7.2  175   4  2   6.5   3.6 | -12.7   9.1  190  23 12   7.3   4.0
 13000 -12.7   9.1  165   4  2   7.6   4.2 | -11.7  10.9  190  23 12   6.4   3.5
 12500 -11.6  11.1  155   5  2   7.6   4.1 | -10.8  12.6  185  24 12   6.5   3.6
 12000 -10.5  13.1  155   5  2   7.3   4.0 |  -9.8  14.4  185  33 17   6.0   3.3
 11500  -9.4  15.1  155   5  3   7.3   4.0 |  -8.9  16.0  180  50 26   6.1   3.3
 11000  -8.4  16.9  155   5  3   6.9   3.8 |  -8.0  17.6  180  66 34   6.2   3.4
 10500  -7.3  18.9  160   6  3   7.1   3.9 |  -7.1  19.2  180  80 41   6.3   3.5
 10250  -6.8  19.8  160   6  3   6.4   3.5 |  -6.6  20.1  180  87 45   5.7   3.1
 10000  -6.4  20.5  165   6  3   6.2   3.4 |  -6.2  20.8  180  89 46   4.9   2.7
  9750  -5.9  21.4  165   6  3   6.7   3.7 |  -5.9  21.4  180  89 46   4.9   2.7
  9500  -5.4  22.3  165   5  3   6.6   3.6 |  -5.5  22.1  180  90 46   4.9   2.7
  9250  -4.9  23.2  165   5  3   6.8   3.7 |  -5.1  22.8  180  90 46   5.3   2.9
  9000  -4.4  24.1  165   5  3   6.3   3.5 |  -4.7  23.5  180  89 46   5.2   2.9
  8750  -4.0  24.8  165   5  2   5.3   2.9 |  -4.4  24.1  180  90 46   4.4   2.4
  8500  -3.6  25.5  160   4  2   5.2   2.9 |  -4.0  24.8  180  93 48   4.3   2.4
  8250  -3.2  26.2  160   4  2   5.6   3.1 |  -3.7  25.3  180  86 44   4.7   2.6
  8000  -2.8  27.0  155   3  2   5.6   3.1 |  -3.4  25.9  180  71 36   4.8   2.6
  7750  -2.5  27.5  155   2  1   3.9   2.1 |  -3.0  26.6  180  56 29   4.1   2.3
  7500  -2.2  28.0  145   2  1   3.4   1.8 |  -2.8  27.0  180  45 23   3.4   1.9
  7250  -2.0  28.4  145   1  1   4.1   2.3 |  -2.5  27.5  180  38 20   3.3   1.8
  7000  -1.7  28.9  140   1  1   4.3   2.4 |  -2.3  27.9  180  32 16   3.4   1.9
  6750  -1.4  29.5  135   1  0   2.6   1.4 |  -2.1  28.2  175  26 13   2.9   1.6
  6500  -1.3  29.7  000   0  0   0.9   0.5 |  -1.9  28.6  175  19 10   2.1   1.2
  6250  -1.1  30.0  000   0  0   1.4   0.8 |  -1.7  28.9  170   8  4   2.3   1.3
  6000  -1.0  30.2  200   1  0   1.3   0.7 |  -1.6  29.1  030   3  2   1.6   0.9
  5750  -1.2  29.8  220   1  0 -11.6  -6.4 |  -1.4  29.5  005  14  7   4.4   2.4
  5500  -3.0  26.6  210   1  1 -32.3 -17.7 |  -0.9  30.4  360  96 50  11.3   6.2

           01/21/2017 at 1400 MST          |       01/21/2017 at 1700 MST
                                           |
CAPE...     0.0    LI...       +3.2        | CAPE...     0.0    LI...       +2.7
CINH...    -0.7    K Index... +16.5        | CINH...     0.0    K Index... +18.6
                                           |
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 -52.3 -62.1  245  21 11   2.9   1.6 | -52.4 -62.3  295  23 12   3.0   1.7
 45000 -47.7 -53.9  285  22 12   2.9   1.6 | -47.9 -54.2  320  36 19   3.0   1.7
 40000 -44.6 -48.3  270  20 10   2.0   1.1 | -44.3 -47.7  325  35 18   2.3   1.3
 38000 -43.4 -46.1  260  19 10  -0.0  -0.0 | -43.0 -45.4  325  34 17  -0.3  -0.2
 36000 -44.1 -47.4  235  21 11  -1.2  -0.6 | -43.8 -46.8  330  33 17  -1.3  -0.7
 34000 -44.8 -48.6  215  25 13  -1.2  -0.6 | -44.7 -48.5  335  33 17  -1.3  -0.7
 32000 -46.7 -52.1  190  49 25  -3.9  -2.1 | -46.5 -51.7  325  18 10  -3.8  -2.1
 30000 -49.0 -56.2  185  82 42  -3.8  -2.1 | -48.8 -55.8  215   9  5  -3.7  -2.0
 29000 -49.3 -56.7  180  94 48   5.6   3.1 | -49.1 -56.4  190  23 12   5.3   2.9
 28000 -47.9 -54.2  180  93 48   4.8   2.6 | -47.7 -53.9  180  47 24   4.6   2.5
 27000 -46.5 -51.7  180  92 47   4.8   2.6 | -46.3 -51.3  180  71 37   4.6   2.5
 26000 -45.0 -49.0  180  91 47   6.2   3.4 | -45.0 -49.0  180  96 49   6.4   3.5
 25000 -42.3 -44.1  180  91 47   9.7   5.3 | -42.1 -43.8  180  96 50   9.6   5.3
 24000 -39.4 -38.9  180  91 47   9.7   5.3 | -39.3 -38.7  180  96 49   9.6   5.3
 23000 -36.5 -33.7  180  90 47   9.6   5.3 | -36.4 -33.5  180  96 49   9.4   5.1
 22000 -33.7 -28.7  180  84 43   9.2   5.1 | -33.8 -28.8  180  73 37   8.7   4.8
 21000 -30.9 -23.6  180  78 40   9.2   5.1 | -31.2 -24.2  180  48 25   8.7   4.8
 20000 -28.2 -18.8  180  70 36   8.5   4.7 | -28.6 -19.5  180  23 12   7.7   4.2
 19500 -27.0 -16.6  180  64 33   8.4   4.6 | -27.5 -17.5  180   9  5   7.6   4.2
 19000 -25.7 -14.3  180  59 30   8.4   4.6 | -26.3 -15.3  350   4  2   7.6   4.2
 18500 -24.5 -12.1  180  53 27   8.4   4.6 | -24.6 -12.3  355  25 13   7.7   4.2
 18000 -22.6  -8.7  180  44 23   8.3   4.6 | -23.5 -10.3  355  39 20   7.6   4.2
 17500 -21.5  -6.7  185  37 19   6.9   3.8 | -22.4  -8.3  355  60 31   7.1   3.9
 17000 -20.5  -4.9  185  30 15   7.0   3.9 | -21.4  -6.5  360  84 43   7.2   3.9
 16500 -19.5  -3.1  190  21 11   6.5   3.6 | -20.3  -4.5  360 106 54   7.0   3.8
 16000 -18.5  -1.3  210   7  3   6.5   3.6 | -19.3  -2.7  360 123 63   7.0   3.8
 15500 -17.6   0.3  335   9  5   7.0   3.8 | -18.3  -0.9  360 139 72   7.2   4.0
 15000 -16.5   2.3  350  22 12   7.7   4.2 | -17.2   1.0  360 141 73   7.4   4.1
 14500 -15.3   4.5  355  36 18   7.7   4.2 | -16.1   3.0  360 143 74   7.3   4.0
 14000 -14.2   6.4  355  47 24   7.1   3.9 | -15.0   5.0  360 144 74   6.9   3.8
 13500 -13.2   8.2  355  58 30   7.2   4.0 | -14.0   6.8  360 145 75   6.9   3.8
 13000 -12.2  10.0  355  68 35   5.7   3.1 | -13.0   8.6  360 147 76   6.2   3.4
 12500 -11.4  11.5  355  76 39   5.8   3.2 | -12.1  10.2  360 151 78   6.2   3.4
 12000 -10.5  13.1  360  82 42   5.9   3.2 | -11.2  11.8  360 152 78   6.1   3.3
 11500  -9.6  14.7  360  84 43   5.9   3.2 | -10.3  13.5  360 151 78   6.1   3.3
 11000  -8.7  16.3  360  91 47   6.2   3.4 |  -9.3  15.3  360 153 79   6.8   3.7
 10500  -7.8  18.0  360 104 54   6.2   3.4 |  -8.3  17.1  360 157 81   6.7   3.7
 10250  -7.3  18.9  360 111 57   6.2   3.4 |  -7.8  18.0  360 160 82   6.1   3.3
 10000  -6.9  19.6  360 132 68   5.9   3.2 |  -7.4  18.7  360 163 84   6.3   3.5
  9750  -6.4  20.5  360 144 74   5.7   3.2 |  -6.9  19.6  360 166 85   7.0   3.8
  9500  -6.0  21.2  360 156 80   5.8   3.2 |  -6.4  20.5  360 168 87   6.8   3.7
  9250  -5.6  21.9  360 167 86   6.0   3.3 |  -5.9  21.4  360 171 88   7.0   3.9
  9000  -5.1  22.8  360 178 91   6.0   3.3 |  -5.4  22.3  360 174 89   6.6   3.6
  8750  -4.7  23.5  360 134 69   5.5   3.0 |  -4.9  23.2  360 176 90   5.3   2.9
  8500  -4.3  24.3  360  48 25   5.2   2.8 |  -4.5  23.9  360 177 91   5.2   2.8
  8250  -3.9  25.0  355   8  4   4.9   2.7 |  -4.1  24.6  360 178 92   5.6   3.1
  8000  -3.6  25.5  355  12  6   4.7   2.6 |  -3.8  25.2  360 179 92   5.7   3.1
  7750  -3.3  26.1  360  17  9   4.8   2.6 |  -3.4  25.9  360 179 92   3.9   2.1
  7500  -3.0  26.6  360  19 10   3.6   2.0 |  -3.2  26.2  360 165 85   2.9   1.6
  7250  -2.8  27.0  360  16  8   2.5   1.4 |  -2.9  26.8  360 112 58   3.5   1.9
  7000  -2.6  27.3  005  12  6   2.6   1.4 |  -2.7  27.1  360  59 31   3.5   1.9
  6750  -2.4  27.7  010   8  4   2.8   1.6 |  -2.5  27.5  360   6  3   2.9   1.6
  6500  -2.2  28.0  020   4  2   3.8   2.1 |  -2.3  27.9  360  46 24   3.1   1.7
  6250  -1.9  28.6  010   6  3   4.2   2.3 |  -2.0  28.4  360  93 48   3.5   1.9
  6000  -1.6  29.1  010   8  4   4.3   2.4 |  -1.7  28.9  360 141 72   4.7   2.6
  5750  -1.1  30.0  005  11  5   8.9   4.9 |  -1.4  29.5  360 162 83   4.8   2.6
  5500  -0.2  31.6  005   9  5  15.6   8.5 |  -1.2  29.8  360 152 78   0.4   0.2
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CINH (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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