Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 211330
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0630 MST Saturday, February 21, 2015

This forecast is for Saturday, February 21, 2015:

If the trigger temperature of 32.3 F/0.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 9930 ft MSL (3172 ft AGL)

Forecast maximum temperature................... 30.0 F/-1.6 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 Sunday 02/22....... Poor

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 06:42:41 / 17:41:44 MST
Total possible sunshine........... 10 hr 59 min 3 sec (659 min 3 sec)
Altitude of sun at 12:12:29 MST... 40.62 degrees

Upper air data from numerical model forecast valid on 02/21/2015 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 9816 ft MSL (3058 ft AGL)
Lifted condensation level....... 9471 ft MSL (2713 ft AGL)
Lifted index.................... +6.1
K index......................... +14.8

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  -55.8 -68.4   275   49   25   2.0   1.1      M     M       M      M    M
 45000  -52.6 -62.7   275   55   28   2.0   1.1      M     M       M      M    M
 40000  -50.4 -58.7   270   70   36   1.4   0.8      M     M       M      M    M
 38000  -49.8 -57.6   270   76   39  -2.0  -1.1      M     M       M      M    M
 36000  -51.2 -60.2   270   79   41  -2.4  -1.3      M     M       M      M    M
 34000  -52.6 -62.7   275   83   43  -2.3  -1.3      M     M       M      M    M
 32000  -51.9 -61.4   270   83   43   2.5   1.4      M     M       M      M    M
 30000  -50.4 -58.7   270   80   41   2.2   1.2      M     M       M      M    M
 29000  -48.9 -56.0   270   78   40   6.3   3.5   18.3  65.0    15.0      M    M
 28000  -47.0 -52.6   275   76   39   6.3   3.5   16.9  62.5    14.1      M    M
 27000  -45.1 -49.2   280   74   38   6.3   3.5   15.7  60.2    13.3      M    M
 26000  -43.1 -45.6   280   70   36   7.5   4.1   14.6  58.2    12.5      M    M
 25000  -40.9 -41.6   280   63   33   7.4   4.0   13.6  56.5    11.9      M    M
 24000  -38.7 -37.7   280   56   29   7.4   4.0   12.7  54.9    11.4      M    M
 23000  -36.4 -33.5   280   50   26   7.4   4.1   11.9  53.5    10.8      M    M
 22000  -34.2 -29.6   280   47   24   7.4   4.1   11.0  51.8    10.2      M    M
 21000  -32.0 -25.6   280   44   22   7.3   4.0   10.2  50.4     9.6      M    M
 20000  -30.1 -22.2   280   39   20   5.5   3.0    9.1  48.3     8.7      M    M
 19500  -29.3 -20.7   285   35   18   5.5   3.0    8.3  46.9     8.1      M    M
 19000  -28.5 -19.3   285   32   17   5.5   3.0    7.5  45.6     7.5      M    M
 18500  -27.7 -17.9   290   29   15   5.6   3.1    6.8  44.3     6.9      M    M
 18000  -26.8 -16.2   295   26   13   6.8   3.7    6.2  43.1     6.3      M    M
 17500  -25.7 -14.3   295   25   13   8.0   4.4    5.9  42.6     6.1      M    M
 17000  -24.5 -12.1   295   24   13   8.1   4.4    5.6  42.1     5.9      M    M
 16500  -23.2  -9.8   290   24   12   9.0   4.9    5.4  41.7     5.7      M    M
 16000  -21.9  -7.4   285   24   12   9.0   4.9    5.3  41.5     5.6      M    M
 15500  -19.9  -3.8   280   22   11   8.5   4.7    5.0  41.0     5.4      M    M
 15000  -18.7  -1.7   270   20   10   8.5   4.7    4.8  40.6     5.2      M    M
 14500  -17.5   0.5   265   18    9   7.9   4.3    4.5  40.1     5.0      M    M
 14000  -16.3   2.7   250   17    9   8.1   4.4    4.2  39.6     4.7      M    M
 13500  -15.2   4.6   240   16    8   6.4   3.5    3.8  38.9     4.3      M    M
 13000  -14.3   6.3   235   15    8   6.5   3.6    3.3  38.0     3.8      M    M
 12500  -13.3   8.1   230   13    7   7.0   3.8    2.8  37.1     3.4      M    M
 12000  -12.3   9.9   230   11    6   5.3   2.9    2.3  36.2     2.9      M    M
 11750  -12.0  10.4   225   10    5   4.7   2.6    1.9  35.5     2.5      M    M
 11500  -11.6  11.1   225    8    4   5.0   2.7    1.5  34.8     2.2      M    M
 11250  -11.3  11.7   220    7    4   4.8   2.6    1.2  34.1     1.8      M    M
 11000  -10.9  12.4   215    6    3   5.4   3.0    0.8  33.4     1.4      M    M
 10750  -10.5  13.1   205    4    2   5.4   3.0    0.5  32.8     1.1      M    M
 10500  -10.1  13.8   190    4    2   4.8   2.7    0.1  32.1     0.8      M    M
 10250   -9.8  14.4   175    3    2   4.8   2.7   -0.3  31.5     0.4      M    M
 10000   -9.4  15.1   155    3    2   5.5   3.0   -0.7  30.8     0.0      M    M
  9750   -9.0  15.8   145    4    2   5.5   3.0   -1.0  30.3    -0.3    243  1.2
  9500   -8.6  16.5   135    4    2   4.9   2.7   -1.3  29.6    -0.6    225  1.1
  9250   -8.2  17.2   125    5    2   4.9   2.7   -1.7  28.9    -1.0    206  1.0
  9000   -7.9  17.8   120    5    3   5.8   3.2   -2.1  28.3    -1.4    188  1.0
  8750   -7.4  18.7   125    6    3   7.5   4.1   -2.3  27.9    -1.6    166  0.8
  8500   -6.8  19.8   125    6    3   7.9   4.3   -2.4  27.6    -1.8    141  0.7
  8250   -6.2  20.8   125    6    3   7.9   4.3   -2.6  27.4    -1.9    117  0.6
  8000   -5.7  21.7   130    7    3   7.3   4.0   -2.7  27.1    -2.1     93  0.5
  7750   -5.2  22.6   130    6    3   7.4   4.0   -2.9  26.7    -2.3     70  0.4
  7500   -4.6  23.7   135    6    3   8.4   4.6   -3.1  26.5    -2.5     45  0.2
  7250   -4.0  24.8   135    5    3   7.3   4.0   -3.2  26.3    -2.7     20  0.1
  7000   -3.6  25.5   135    5    3   4.4   2.4   -2.9  26.7    -2.4      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           02/21/2015 at 0800 MST          |       02/21/2015 at 1100 MST
                                           |
K index... +15.7  LI... +0.1               | K index... +15.9  LI... +0.6
CAPE... +12.7  CIN... -0.6                 | CAPE... 0.0  CIN... -1.1
                                           |
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 -54.6 -66.3  285  48 25   2.0   1.1 | -54.3 -65.7  285  43 22   1.2   0.7
 45000 -51.5 -60.7  275  50 26   2.0   1.1 | -52.3 -62.1  285  52 27   1.2   0.7
 40000 -51.6 -60.9  275  62 32  -0.4  -0.2 | -51.4 -60.5  280  64 33   0.6   0.3
 38000 -51.9 -61.4  275  68 35  -1.0  -0.5 | -51.1 -60.0  280  70 36  -0.5  -0.3
 36000 -52.5 -62.5  275  73 37  -1.1  -0.6 | -51.5 -60.7  280  72 37  -0.7  -0.4
 34000 -53.2 -63.8  275  77 40  -1.1  -0.6 | -51.9 -61.4  275  75 39  -0.7  -0.4
 32000 -52.5 -62.5  275  78 40   2.4   1.3 | -51.3 -60.3  275  75 39   1.7   0.9
 30000 -50.9 -59.6  275  77 40   2.2   1.2 | -50.3 -58.5  275  74 38   1.7   1.0
 29000 -49.6 -57.3  275  74 38   5.2   2.9 | -49.4 -56.9  275  72 37   4.9   2.7
 28000 -48.0 -54.4  275  71 36   5.3   2.9 | -47.6 -53.7  275  66 34   4.8   2.6
 27000 -46.4 -51.5  275  67 34   5.3   2.9 | -46.2 -51.2  275  62 32   4.8   2.6
 26000 -44.5 -48.1  275  63 32   9.6   5.2 | -44.6 -48.3  275  57 29   7.1   3.9
 25000 -41.8 -43.2  275  59 30   9.1   5.0 | -42.5 -44.5  270  51 26   6.8   3.8
 24000 -39.1 -38.4  275  55 28   9.1   5.0 | -40.5 -40.9  270  45 23   6.8   3.8
 23000 -36.5 -33.7  280  51 26   6.7   3.7 | -38.4 -37.1  270  39 20   7.9   4.3
 22000 -34.4 -29.9  275  46 24   7.0   3.8 | -36.0 -32.8  270  32 17   7.8   4.3
 21000 -32.3 -26.1  275  41 21   6.9   3.8 | -33.7 -28.7  270  26 13   7.8   4.3
 20000 -30.4 -22.7  275  34 18   6.0   3.3 | -31.3 -24.3  270  21 11   8.4   4.6
 19500 -29.5 -21.1  280  31 16   6.0   3.3 | -30.0 -22.0  270  19 10   8.4   4.6
 19000 -28.6 -19.5  280  27 14   6.0   3.3 | -28.8 -19.8  270  17  9   8.4   4.6
 18500 -27.7 -17.9  280  24 12   6.1   3.3 | -27.5 -17.5  275  15  8   8.4   4.6
 18000 -26.8 -16.2  285  20 10   6.8   3.7 | -26.3 -15.3  275  13  7   8.2   4.5
 17500 -25.7 -14.3  285  19 10   7.7   4.2 | -25.1 -13.2  280  13  7   8.1   4.4
 17000 -24.6 -12.3  290  18  9   7.7   4.3 | -23.9 -11.0  280  13  7   8.0   4.4
 16500 -23.3  -9.9  290  18  9   8.7   4.8 | -22.8  -9.0  280  13  6   7.7   4.2
 16000 -22.1  -7.8  290  19 10   8.6   4.7 | -21.6  -6.9  280  12  6   7.6   4.2
 15500 -20.8  -5.4  290  19 10   8.5   4.6 | -20.4  -4.7  275  11  6   8.1   4.5
 15000 -18.9  -2.0  280  16  8   8.4   4.6 | -19.2  -2.6  275  11  6   8.1   4.5
 14500 -17.7   0.1  275  15  8   8.2   4.5 | -18.1  -0.6  270  10  5   7.2   4.0
 14000 -16.5   2.3  270  15  8   8.4   4.6 | -17.0   1.4  265  10  5   7.1   3.9
 13500 -15.4   4.3  265  14  7   6.3   3.4 | -16.0   3.2  260  10  5   6.8   3.7
 13000 -14.5   5.9  255  13  7   6.5   3.6 | -15.0   5.0  250  10  5   6.7   3.7
 12500 -13.5   7.7  245  12  6   6.2   3.4 | -14.0   6.8  240  10  5   7.1   3.9
 12000 -12.7   9.1  235  12  6   5.1   2.8 | -12.9   8.8  235  11  5   6.7   3.7
 11750 -12.3   9.9  225  11  6   5.2   2.9 | -12.5   9.5  230  11  6   5.4   3.0
 11500 -11.9  10.6  220  11  6   5.7   3.1 | -12.1  10.2  225  12  6   5.8   3.2
 11250 -11.5  11.3  215  10  5   5.7   3.1 | -11.6  11.1  215  12  6   6.2   3.4
 11000 -11.1  12.0  210  10  5   5.2   2.8 | -11.2  11.8  210  13  6   6.2   3.4
 10750 -10.7  12.7  205  10  5   5.1   2.8 | -10.7  12.7  205  13  7   5.5   3.0
 10500 -10.3  13.5  200  10  5   5.6   3.1 | -10.4  13.3  200  14  7   5.4   3.0
 10250  -9.9  14.2  195   9  5   5.5   3.0 |  -9.5  14.9  190  14  7   6.0   3.3
 10000  -9.5  14.9  190   9  5   5.4   3.0 |  -9.1  15.6  185  15  8   5.5   3.0
  9750  -9.1  15.6  185   9  4   5.4   2.9 |  -8.7  16.3  180  16  8   5.6   3.1
  9500  -8.7  16.3  180   9  5   5.5   3.0 |  -8.2  17.2  180  16  8   6.2   3.4
  9250  -8.3  17.1  175   9  5   5.3   2.9 |  -7.8  18.0  175  16  8   6.1   3.3
  9000  -7.9  17.8  170   9  5   6.0   3.3 |  -7.4  18.7  175  17  9   5.9   3.3
  8750  -7.4  18.7  170  10  5   6.9   3.8 |  -6.9  19.6  170  16  8   7.9   4.3
  8500  -6.9  19.6  170  10  5   6.9   3.8 |  -6.2  20.8  165  16  8   9.4   5.2
  8250  -6.4  20.5  165  10  5   6.9   3.8 |  -5.6  21.9  160  16  8   9.2   5.1
  8000  -5.9  21.4  160   9  5   7.9   4.3 |  -4.9  23.2  160  15  8   9.1   5.0
  7750  -5.3  22.5  160   9  5   8.5   4.7 |  -4.2  24.4  160  14  7  12.1   6.6
  7500  -4.7  23.5  155   8  4   8.4   4.6 |  -3.1  26.4  155  13  6  18.3  10.1
  7250  -4.1  24.6  155   7  4   7.6   4.2 |  -1.9  28.6  150  11  6   6.9   3.8
  7000  -3.6  25.5  150   7  4   5.4   2.9 |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           02/21/2015 at 1400 MST          |       02/21/2015 at 1700 MST
                                           |
K index... +17.1  LI... +0.5               | K index... +17.9  LI... +0.1
CAPE... +31.4  CIN... M                    | CAPE... +7.3  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 -54.0 -65.2  285  45 23   1.2   0.6 | -54.3 -65.7  285  47 24   1.5   0.8
 45000 -52.2 -62.0  290  55 28   1.2   0.6 | -52.1 -61.8  285  54 28   1.5   0.8
 40000 -50.5 -58.9  285  66 34   1.1   0.6 | -51.2 -60.2  285  67 35   0.4   0.2
 38000 -49.9 -57.8  280  71 37  -0.3  -0.1 | -51.0 -59.8  280  73 38  -0.9  -0.5
 36000 -50.7 -59.3  280  76 39  -1.2  -0.7 | -52.1 -61.8  280  86 44  -1.6  -0.9
 34000 -51.4 -60.5  280  80 41  -1.1  -0.6 | -53.1 -63.6  280  97 50  -1.4  -0.8
 32000 -50.9 -59.6  280  80 41   1.6   0.9 | -51.6 -60.9  280  97 50   3.8   2.1
 30000 -50.0 -58.0  280  78 40   1.7   0.9 | -49.3 -56.7  280  94 48   3.8   2.1
 29000 -49.1 -56.4  280  74 38   4.0   2.2 | -48.0 -54.4  280  89 46   4.8   2.6
 28000 -47.9 -54.2  280  67 35   4.1   2.2 | -46.6 -51.9  280  81 42   4.9   2.7
 27000 -46.7 -52.1  280  61 31   4.1   2.2 | -45.1 -49.2  280  74 38   4.9   2.7
 26000 -45.4 -49.7  280  54 28   6.1   3.3 | -43.6 -46.5  280  66 34   5.2   2.9
 25000 -43.4 -46.1  280  43 22   6.9   3.8 | -42.1 -43.8  280  55 28   5.3   2.9
 24000 -41.3 -42.3  275  33 17   6.9   3.8 | -40.5 -40.9  275  43 22   5.3   2.9
 23000 -38.5 -37.3  275  24 12   9.2   5.0 | -38.2 -36.8  270  31 16   8.5   4.7
 22000 -35.8 -32.4  275  23 12   9.0   4.9 | -35.7 -32.3  275  28 14   8.4   4.6
 21000 -33.2 -27.8  280  22 11   9.0   5.0 | -33.2 -27.8  280  24 13   8.4   4.6
 20000 -30.6 -23.1  285  21 11   8.3   4.6 | -30.7 -23.3  280  22 11   8.4   4.6
 19500 -29.4 -20.9  285  21 11   8.3   4.6 | -29.5 -21.1  280  22 11   8.5   4.6
 19000 -28.1 -18.6  285  20 10   8.3   4.6 | -28.2 -18.8  285  21 11   8.5   4.6
 18500 -26.9 -16.4  285  20 10   8.3   4.6 | -26.9 -16.4  285  20 10   8.5   4.7
 18000 -25.7 -14.3  285  20 10   8.0   4.4 | -25.7 -14.3  285  19 10   8.5   4.6
 17500 -24.5 -12.1  285  20 10   7.9   4.3 | -24.4 -11.9  285  18  9   8.5   4.6
 17000 -23.4 -10.1  285  20 11   7.9   4.3 | -23.2  -9.8  285  16  8   8.4   4.6
 16500 -22.2  -8.0  285  21 11   8.1   4.4 | -22.0  -7.6  280  15  8   8.3   4.5
 16000 -21.0  -5.8  285  21 11   8.1   4.5 | -20.7  -5.3  275  14  7   8.3   4.6
 15500 -19.8  -3.6  280  21 11   7.5   4.1 | -19.6  -3.3  270  13  7   7.7   4.2
 15000 -18.7  -1.7  280  21 11   7.6   4.2 | -18.4  -1.1  260  11  6   7.8   4.3
 14500 -17.6   0.3  275  21 11   7.3   4.0 | -17.3   0.9  250  10  5   7.7   4.2
 14000 -16.5   2.3  270  20 10   7.2   4.0 | -16.1   3.0  240   9  5   7.7   4.2
 13500 -15.5   4.1  265  20 10   6.9   3.8 | -15.0   5.0  225   9  4   7.4   4.0
 13000 -14.5   5.9  255  20 10   6.8   3.7 | -14.0   6.8  215   8  4   7.3   4.0
 12500 -13.5   7.7  245  20 10   6.6   3.6 | -12.9   8.8  200   8  4   7.5   4.1
 12000 -12.6   9.3  235  19 10   6.0   3.3 | -11.7  10.9  190   7  4   6.7   3.7
 11750 -12.2  10.0  230  19 10   5.3   2.9 | -11.3  11.7  185   7  4   5.3   2.9
 11500 -11.8  10.8  225  19 10   6.0   3.3 | -10.9  12.4  175   7  4   6.5   3.6
 11250 -11.3  11.7  215  19 10   6.4   3.5 | -10.4  13.3  170   7  3   7.1   3.9
 11000 -10.8  12.6  210  18  9   6.3   3.4 |  -9.9  14.2  165   6  3   6.8   3.7
 10750 -10.4  13.3  205  18  9   6.1   3.3 |  -9.4  15.1  155   6  3   5.8   3.2
 10500 -10.0  14.0  200  18  9   6.2   3.4 |  -9.0  15.8  145   6  3   5.9   3.2
 10250  -9.5  14.9  195  17  9   6.4   3.5 |  -8.6  16.5  135   5  3   6.6   3.6
 10000  -9.0  15.8  190  17  9   6.3   3.5 |  -8.1  17.4  125   5  3   6.5   3.6
  9750  -8.6  16.5  180  17  9   6.6   3.6 |  -7.6  18.3  115   6  3   6.3   3.5
  9500  -7.5  18.5  175  16  8   7.0   3.9 |  -6.7  19.9  085   6  3   6.4   3.5
  9250  -7.0  19.4  170  16  8   7.0   3.8 |  -6.2  20.8  075   7  4   6.4   3.5
  9000  -6.5  20.3  165  16  8   7.2   3.9 |  -5.8  21.6  065   8  4   6.3   3.5
  8750  -6.0  21.2  160  15  8   8.7   4.8 |  -5.3  22.5  060   9  5   7.1   3.9
  8500  -5.3  22.5  155  14  7   9.7   5.3 |  -4.7  23.5  055  10  5   7.9   4.3
  8250  -4.6  23.7  150  14  7   9.5   5.2 |  -4.2  24.4  045  11  6   7.7   4.2
  8000  -3.9  25.0  150  13  7   8.9   4.9 |  -3.6  25.5  040  12  6   7.4   4.1
  7750  -3.2  26.2  150  12  6  11.2   6.1 |  -3.1  26.4  035  12  6   8.3   4.6
  7500  -2.2  28.0  140  10  5  16.5   9.1 |  -2.4  27.7  035  10  5  10.4   5.7
  7250  -1.2  29.8  135   8  4   6.6   3.6 |  -1.7  28.9  030   8  4   6.5   3.6
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

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 Air Force Academy
in Colorado Springs, Colorado at

                   North Latitude:  38 deg 58 min 48.000 sec
                   West Longitude: 104 deg 49 min 12.000 sec
                   Elevation: 6572 feet (2003 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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