Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 191307
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0607 MST Monday, February 19, 2018

This forecast is for Monday, February 19, 2018:

If the trigger temperature of 42.5 F/5.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 56 ft/min (0.3 m/s)
   Maximum height of thermals.................. 9845 ft MSL (2198 ft AGL)

Forecast maximum temperature................... 35.0 F/2.1 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8775 ft MSL (1128 ft AGL)
Thermal soaring outlook for Tuesday 02/20...... Fair

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

Remarks...

Sunrise/Sunset.................... 06:45:10 / 17:41:00 MST
Total possible sunshine........... 10 hr 55 min 50 sec (655 min 50 sec)
Altitude of sun at 12:13:05 MST... 39.84 degrees

Upper air data from numerical model forecast valid on 02/19/2018 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 13582 ft MSL (5935 ft AGL)
Lifted condensation level....... 11336 ft MSL (3689 ft AGL)
Lifted index.................... +9.4
K index......................... -12.3

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  -63.7 -82.7   245   53   27   5.0   2.8      M     M       M      M    M
 45000  -56.1 -69.0   240   55   28   4.9   2.7      M     M       M      M    M
 40000  -57.6 -71.7   235   49   25  -1.8  -1.0      M     M       M      M    M
 38000  -57.8 -72.0   230   46   24   4.3   2.4      M     M       M      M    M
 36000  -55.1 -67.2   225   44   22   4.5   2.5      M     M       M      M    M
 34000  -52.4 -62.3   220   42   22   4.7   2.6      M     M       M      M    M
 32000  -48.4 -55.1   220   41   21   6.9   3.8      M     M       M      M    M
 30000  -44.3 -47.7   220   40   21   7.0   3.8      M     M       M      M    M
 29000  -42.1 -43.8   225   39   20   7.3   4.0   24.0  75.2    17.4      M    M
 28000  -39.9 -39.8   225   38   20   7.3   4.0   23.0  73.5    16.8      M    M
 27000  -37.7 -35.9   225   37   19   7.3   4.0   22.2  72.0    16.4      M    M
 26000  -35.6 -32.1   225   36   19   6.4   3.5   21.2  70.2    15.8      M    M
 25000  -33.7 -28.7   230   36   18   6.4   3.5   19.9  67.9    14.9      M    M
 24000  -31.2 -24.2   235   36   18   6.5   3.6   18.5  65.3    13.9      M    M
 23000  -29.2 -20.6   235   36   18   7.2   3.9   17.4  63.4    13.2      M    M
 22000  -27.1 -16.8   235   35   18   7.2   4.0   16.5  61.7    12.6      M    M
 21000  -24.9 -12.8   235   35   18   7.2   4.0   15.7  60.2    12.0      M    M
 20000  -22.8  -9.0   235   34   17   7.1   3.9   14.7  58.5    11.3      M    M
 19500  -21.7  -7.1   240   33   17   7.1   3.9   14.3  57.7    11.0      M    M
 19000  -20.6  -5.1   240   32   16   7.1   3.9   13.8  56.9    10.7      M    M
 18500  -19.5  -3.1   240   31   16   7.1   3.9   13.4  56.1    10.4      M    M
 18000  -18.5  -1.3   240   30   16   7.5   4.1   13.0  55.4    10.1      M    M
 17500  -17.3   0.9   245   31   16   7.7   4.2   12.7  54.8     9.8      M    M
 17000  -16.1   3.0   245   33   17   7.6   4.2   12.3  54.2     9.6      M    M
 16500  -15.2   4.6   245   31   16   5.7   3.1   11.8  53.2     9.1      M    M
 16000  -14.3   6.3   245   28   14   6.0   3.3   11.1  52.0     8.6      M    M
 15500  -13.6   7.5   240   24   13   4.0   2.2   10.4  50.7     7.9      M    M
 15000  -13.0   8.6   240   21   11   3.9   2.1    9.4  48.9     7.0      M    M
 14500  -12.5   9.5   235   18    9   5.8   3.2    8.5  47.3     6.1      M    M
 14000  -11.4  11.5   240   22   11   7.2   4.0    8.1  46.5     5.8      M    M
 13500  -10.3  13.5   240   26   13   6.9   3.8    7.7  45.9     5.4      M    M
 13000   -9.4  15.1   240   28   14   5.6   3.1    7.1  44.8     4.9      M    M
 12500   -8.3  17.1   240   28   15  10.2   5.6    6.8  44.3     4.6      M    M
 12000   -7.1  19.2   240   27   14   7.2   3.9    6.6  43.9     4.3      M    M
 11750   -6.6  20.1   240   27   14   7.1   3.9    6.4  43.5     4.1      M    M
 11500   -6.1  21.0   240   26   14   8.6   4.7    6.2  43.2     3.9      M    M
 11250   -5.5  22.1   235   26   13   6.0   3.3    6.1  43.0     3.8      M    M
 11000   -5.3  22.5   235   25   13   2.2   1.2    5.6  42.1     3.3      M    M
 10750   -5.1  22.8   230   24   12   3.9   2.2    5.1  41.2     2.8      M    M
 10500   -4.9  23.2   230   23   12   1.0   0.5    4.6  40.2     2.3      M    M
 10250   -4.9  23.2   225   21   11  -0.9  -0.5    3.8  38.8     1.5      M    M
 10000   -4.9  23.2   225   20   10   0.3   0.2    3.0  37.4     0.8      M    M
  9750   -4.9  23.2   220   18    9   0.2   0.1    2.3  36.1     0.0      M    M
  9500   -4.9  23.2   215   17    9  -0.6  -0.3    1.5  34.8    -0.7    249  1.3
  9250   -5.0  23.0   210   15    8  -0.9  -0.5    0.7  33.3    -1.5    244  1.2
  9000   -5.0  23.0   205   14    7   1.1   0.6   -0.0  31.9    -2.2    236  1.2
  8750   -4.6  23.7   195   11    6  -1.4  -0.8   -1.2  29.9    -3.3    211  1.1
  8500   -5.0  23.0   190    9    4  -6.5  -3.6   -2.3  27.9    -4.4    215  1.1
  8250   -5.3  22.5   180    7    3  -0.5  -0.3   -3.3  26.0    -5.5    217  1.1
  8000   -5.0  23.0   170    6    3   7.9   4.3   -3.8  25.2    -5.9    201  1.0
  7750   -4.4  24.1   150    4    2   3.8   2.1   -3.9  24.9    -6.1    176  0.9
  7500      M     M     M    M    M     M     M      M     M       M      M    M
  7250      M     M     M    M    M     M     M      M     M       M      M    M
  7000      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

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

           02/19/2018 at 0800 MST          |       02/19/2018 at 1100 MST
                                           |
CAPE...     0.0    LI...       +3.2        | CAPE...     0.0    LI...       +3.6
CINH...     0.0    K Index... -13.3        | CINH...     0.0    K Index... -32.1
                                           |
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 -62.5 -80.5  245  50 26   5.0   2.7 | -61.8 -79.2  205 116 60   5.0   2.7
 45000 -55.0 -67.0  240  55 28   4.9   2.7 | -54.4 -65.9  200 132 68   4.9   2.7
 40000 -56.1 -69.0  230  49 25  -1.5  -0.8 | -55.8 -68.4  195 158 81  -1.7  -0.9
 38000 -56.3 -69.3  230  47 24   3.2   1.8 | -56.2 -69.2  190 166 86   3.1   1.7
 36000 -54.3 -65.7  225  47 24   3.3   1.8 | -54.3 -65.7  190 168 87   3.2   1.7
 34000 -52.3 -62.1  220  47 24   3.0   1.6 | -52.4 -62.3  190 170 88   2.8   1.5
 32000 -48.7 -55.7  220  45 23   6.3   3.5 | -48.6 -55.5  190 172 88   6.8   3.7
 30000 -44.9 -48.8  220  43 22   6.2   3.4 | -44.5 -48.1  190 173 89   6.8   3.7
 29000 -42.7 -44.9  220  42 22   7.6   4.2 | -42.5 -44.5  190 172 89   6.6   3.6
 28000 -40.4 -40.7  220  41 21   7.6   4.2 | -40.5 -40.9  190 171 88   6.6   3.6
 27000 -38.1 -36.6  220  41 21   7.6   4.2 | -38.6 -37.5  190 169 87   6.6   3.6
 26000 -35.9 -32.6  225  40 21   6.9   3.8 | -36.6 -33.9  190 168 86   6.9   3.8
 25000 -33.8 -28.8  225  39 20   7.0   3.8 | -34.0 -29.2  190 165 85   6.9   3.8
 24000 -31.2 -24.2  225  38 19   7.0   3.8 | -31.9 -25.4  190 162 83   6.9   3.8
 23000 -29.1 -20.4  225  37 19   6.9   3.8 | -29.8 -21.6  190 159 82   7.4   4.1
 22000 -27.0 -16.6  230  36 18   6.9   3.8 | -27.6 -17.7  190 157 81   7.4   4.1
 21000 -25.0 -13.0  230  35 18   6.9   3.8 | -25.4 -13.7  190 154 79   7.4   4.1
 20000 -23.0  -9.4  230  34 17   6.5   3.6 | -23.2  -9.8  190 152 78   7.1   3.9
 19500 -22.0  -7.6  230  33 17   6.5   3.6 | -22.1  -7.8  190 152 78   7.1   3.9
 19000 -21.0  -5.8  230  32 17   6.5   3.6 | -21.1  -6.0  190 151 78   7.1   3.9
 18500 -20.0  -4.0  230  32 16   6.5   3.6 | -20.0  -4.0  190 151 78   7.1   3.9
 18000 -19.1  -2.4  230  31 16   6.7   3.7 | -19.0  -2.2  190 151 77   7.3   4.0
 17500 -18.0  -0.4  230  28 14   6.9   3.8 | -17.8  -0.0  190 153 79   7.6   4.2
 17000 -17.0   1.4  230  25 13   7.0   3.8 | -16.7   1.9  185 156 81   7.6   4.1
 16500 -15.9   3.4  225  21 11   6.8   3.8 | -15.5   4.1  185 158 81   8.1   4.4
 16000 -14.9   5.2  220  17  9   6.9   3.8 | -14.3   6.3  185 159 82   8.1   4.4
 15500 -13.9   7.0  215  14  7   6.1   3.4 | -13.2   8.2  185 158 82   6.1   3.3
 15000 -13.0   8.6  225  16  8   5.9   3.2 | -12.4   9.7  185 151 78   5.4   3.0
 14500 -12.2  10.0  230  18  9   4.8   2.6 | -11.6  11.1  190 144 74   4.8   2.6
 14000 -11.7  10.9  235  20 11   3.7   2.0 | -11.0  12.2  190 138 71   3.9   2.1
 13500 -11.2  11.8  240  23 12   4.0   2.2 | -10.4  13.3  190 132 68   3.8   2.1
 13000 -10.5  13.1  245  25 13   4.4   2.4 | -10.0  14.0  190 129 66   3.0   1.6
 12500  -9.7  14.5  245  26 13   9.4   5.1 |  -9.2  15.4  190 128 66   8.5   4.7
 12000  -8.3  17.1  245  25 13   8.7   4.8 |  -8.2  17.2  190 130 67   7.2   3.9
 11750  -7.7  18.1  245  25 13   8.3   4.5 |  -7.6  18.3  190 132 68   6.5   3.6
 11500  -7.0  19.4  240  25 13  10.6   5.8 |  -7.1  19.2  190 134 69  10.0   5.5
 11250  -6.2  20.8  240  24 13  10.5   5.8 |  -6.3  20.7  190 136 70  11.4   6.3
 11000  -5.5  22.1  240  24 12   7.7   4.2 |  -5.6  21.9  190 137 71   8.6   4.7
 10750  -4.9  23.2  240  24 12   9.4   5.1 |  -4.9  23.2  190 139 72  10.1   5.5
 10500  -4.3  24.3  240  24 12   5.7   3.1 |  -4.2  24.4  190 141 73   7.0   3.8
 10250  -4.2  24.4  235  23 12  -1.8  -1.0 |  -3.8  25.2  185 144 74   5.2   2.8
 10000  -4.5  23.9  235  22 11  -4.0  -2.2 |  -3.4  25.9  185 147 76   6.4   3.5
  9750  -4.7  23.5  235  21 11  -2.5  -1.3 |  -2.9  26.8  185 150 77   7.0   3.8
  9500  -5.0  23.0  230  20 10  -5.9  -3.2 |  -2.4  27.7  185 153 79   3.4   1.9
  9250  -5.7  21.7  230  19 10  -9.8  -5.4 |  -2.5  27.5  185 157 81  -1.9  -1.1
  9000  -6.3  20.7  225  16  8  -4.8  -2.6 |  -2.5  27.5  185 163 84   2.6   1.4
  8750  -6.4  20.5  220  14  7  -2.0  -1.1 |  -2.1  28.2  185 170 88   6.7   3.7
  8500  -6.6  20.1  210  12  6  -1.2  -0.7 |  -1.7  28.9  180 177 91   4.2   2.3
  8250  -6.6  20.1  200  11  6   0.5   0.3 |  -1.5  29.3  180 183 94   2.4   1.3
  8000  -6.5  20.3  190  10  5   3.4   1.9 |  -0.4  31.3  180 185 95  17.8   9.8
  7750  -5.9  21.4  180   9  5  14.3   7.8 |   1.8  35.2  180 180 93  43.1  23.7
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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

           02/19/2018 at 1400 MST          |       02/19/2018 at 1700 MST
                                           |
CAPE...     0.0    LI...       +1.5        | CAPE...    +0.5    LI...       -1.4
CINH...     0.0    K Index...  -8.0        | CINH...    -8.5    K Index...  +8.2
                                           |
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 -62.3 -80.1  235  48 25   5.3   2.9 | -60.5 -76.9  240  48 25   4.7   2.6
 45000 -54.0 -65.2  235  56 29   5.3   2.9 | -53.1 -63.6  235  55 28   4.6   2.5
 40000 -52.7 -62.9  230  55 28   0.4   0.2 | -50.7 -59.3  225  54 28   1.3   0.7
 38000 -52.4 -62.3  225  55 28   1.1   0.6 | -50.0 -58.0  225  54 28   0.2   0.1
 36000 -51.7 -61.1  225  56 29   1.0   0.6 | -49.9 -57.8  225  56 29   0.3   0.1
 34000 -51.1 -60.0  220  56 29   1.2   0.7 | -49.7 -57.5  220  58 30  -0.0  -0.0
 32000 -47.9 -54.2  220  56 29   5.8   3.2 | -47.3 -53.1  220  59 30   4.9   2.7
 30000 -44.4 -47.9  220  56 29   5.8   3.2 | -44.3 -47.7  225  59 30   4.9   2.7
 29000 -42.6 -44.7  220  55 29   6.1   3.3 | -42.6 -44.7  225  60 31   6.1   3.4
 28000 -40.8 -41.4  220  55 28   6.1   3.3 | -40.8 -41.4  225  60 31   6.2   3.4
 27000 -39.0 -38.2  220  54 28   6.1   3.3 | -38.9 -38.0  225  61 31   6.2   3.4
 26000 -37.1 -34.8  225  54 28   6.9   3.8 | -37.1 -34.8  230  61 32   5.3   2.9
 25000 -35.0 -31.0  225  53 27   6.8   3.8 | -35.6 -32.1  230  60 31   5.0   2.8
 24000 -33.0 -27.4  225  53 27   6.8   3.8 | -34.1 -29.4  225  59 31   5.0   2.8
 23000 -30.9 -23.6  225  52 27   7.0   3.8 | -32.6 -26.7  225  59 30   5.9   3.2
 22000 -28.9 -20.0  225  51 26   7.0   3.8 | -30.6 -23.1  225  57 29   6.6   3.6
 21000 -26.8 -16.2  230  50 26   7.0   3.8 | -28.6 -19.5  225  56 29   6.6   3.6
 20000 -24.3 -11.7  230  47 24   6.2   3.4 | -26.3 -15.3  225  53 27   5.8   3.2
 19500 -23.4 -10.1  230  46 24   6.1   3.4 | -25.4 -13.7  225  51 26   5.8   3.2
 19000 -22.5  -8.5  230  45 23   6.1   3.4 | -24.5 -12.1  225  49 25   5.8   3.2
 18500 -21.5  -6.7  230  44 23   6.1   3.4 | -23.7 -10.7  225  48 24   5.9   3.2
 18000 -20.6  -5.1  230  43 22   6.2   3.4 | -22.8  -9.0  225  46 24   6.3   3.5
 17500 -19.7  -3.5  230  39 20   6.3   3.5 | -21.8  -7.2  225  43 22   7.6   4.2
 17000 -18.7  -1.7  230  35 18   6.2   3.4 | -20.6  -5.1  225  40 21   7.5   4.1
 16500 -17.7   0.1  230  31 16   8.5   4.7 | -19.5  -3.1  225  39 20   8.7   4.8
 16000 -16.4   2.5  230  27 14   8.3   4.6 | -18.2  -0.8  220  39 20   8.7   4.8
 15500 -15.2   4.6  225  24 12   7.9   4.4 | -16.9   1.6  220  38 20   8.7   4.7
 15000 -14.1   6.6  225  26 13   7.8   4.3 | -15.6   3.9  220  38 20   8.6   4.7
 14500 -12.9   8.8  225  27 14   7.5   4.1 | -14.3   6.3  220  37 19   8.5   4.7
 14000 -11.9  10.6  225  30 15   7.0   3.9 | -13.1   8.4  220  36 19   8.4   4.6
 13500 -10.8  12.6  225  32 16   6.7   3.7 | -11.9  10.6  215  35 18   8.2   4.5
 13000 -10.0  14.0  225  33 17   4.4   2.4 | -10.8  12.6  215  34 17   6.1   3.4
 12500  -9.1  15.6  220  33 17   9.3   5.1 |  -9.5  14.9  215  32 16  12.3   6.7
 12000  -7.9  17.8  220  32 17   7.3   4.0 |  -8.1  17.4  210  30 15   8.0   4.4
 11750  -7.4  18.7  215  32 16   6.7   3.7 |  -7.5  18.5  210  29 15   7.7   4.2
 11500  -6.9  19.6  215  31 16   9.8   5.4 |  -6.9  19.6  210  28 15  10.7   5.9
 11250  -6.1  21.0  215  30 16  10.3   5.7 |  -6.0  21.2  205  27 14  10.2   5.6
 11000  -5.5  22.1  210  30 15   7.5   4.1 |  -5.5  22.1  205  26 14   6.9   3.8
 10750  -4.9  23.2  210  29 15   8.8   4.8 |  -4.9  23.2  205  26 13   7.4   4.0
 10500  -4.3  24.3  210  28 14   6.5   3.6 |  -4.4  24.1  205  25 13   8.7   4.8
 10250  -4.0  24.8  210  27 14   3.1   1.7 |  -3.8  25.2  205  25 13   6.2   3.4
 10000  -3.8  25.2  205  26 13   2.3   1.3 |  -3.5  25.7  205  24 13   2.7   1.5
  9750  -3.6  25.5  205  25 13   3.5   1.9 |  -3.2  26.2  200  23 12   3.9   2.1
  9500  -3.4  25.9  205  24 12  -0.5  -0.3 |  -3.0  26.6  200  22 12   2.8   1.5
  9250  -3.8  25.2  205  22 11  -8.9  -4.9 |  -2.9  26.8  200  21 11  -2.1  -1.1
  9000  -4.4  24.1  200  20 10  -3.6  -2.0 |  -3.2  26.2  195  20 10  -3.2  -1.7
  8750  -4.3  24.3  195  18  9   2.0   1.1 |  -3.3  26.1  195  18  9  -1.0  -0.5
  8500  -4.3  24.3  190  15  8   1.6   0.9 |  -3.4  25.9  195  17  9  -2.3  -1.2
  8250  -4.0  24.8  185  14  7   4.2   2.3 |  -3.7  25.3  190  15  8  -4.4  -2.4
  8000  -3.6  25.5  180  13  7   6.9   3.8 |  -3.9  25.0  190  13  7   1.9   1.1
  7750  -2.8  27.0  180  12  6  18.1   9.9 |  -3.2  26.2  185  10  5  14.9   8.2
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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).  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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