Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 161310
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0710 MDT Thursday, April 16, 2015

This forecast is for Thursday, April 16, 2015:

If the trigger temperature of 42.8 F/6.0 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8948 ft MSL (2190 ft AGL)

Forecast maximum temperature................... 38.0 F/3.8 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................. 7927 ft MSL (1170 ft AGL)
Thermal soaring outlook for Friday 04/17....... Poor

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

Remarks...

Sunrise/Sunset.................... 06:21:22 / 19:36:01 MDT
Total possible sunshine........... 13 hr 14 min 38 sec (794 min 38 sec)
Altitude of sun at 12:58:50 MDT... 61.26 degrees

Upper air data from numerical model forecast valid on 04/16/2015 at 0600 MDT

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 11923 ft MSL (5165 ft AGL)
Lifted condensation level....... 10104 ft MSL (3347 ft AGL)
Lifted index.................... +4.5
K index......................... +19.9

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  -56.5 -69.7   240   14    7   3.8   2.1      M     M       M      M    M
 45000  -50.8 -59.4   245   27   14   3.3   1.8      M     M       M      M    M
 40000  -48.8 -55.8   205   24   12   1.2   0.7      M     M       M      M    M
 38000  -48.8 -55.8   200   29   15  -1.9  -1.0      M     M       M      M    M
 36000  -49.9 -57.8   210   39   20  -1.8  -1.0      M     M       M      M    M
 34000  -51.0 -59.8   210   49   25  -0.6  -0.4      M     M       M      M    M
 32000  -50.2 -58.4   210   52   27   1.5   0.8      M     M       M      M    M
 30000  -49.2 -56.6   205   55   28   4.8   2.6      M     M       M      M    M
 29000  -46.9 -52.4   205   49   25   7.9   4.3   19.9  67.8    12.8      M    M
 28000  -43.9 -47.0   200   41   21   7.9   4.3   19.0  66.2    12.3      M    M
 27000  -41.6 -42.9   195   35   18   8.0   4.4   18.5  65.2    12.0      M    M
 26000  -39.0 -38.2   195   35   18   8.9   4.9   18.0  64.4    11.8      M    M
 25000  -36.3 -33.3   195   36   19   8.9   4.9   17.6  63.7    11.6      M    M
 24000  -33.7 -28.7   195   38   19   8.9   4.9   17.4  63.3    11.5      M    M
 23000  -31.1 -24.0   195   39   20   8.8   4.8   17.0  62.6    11.3      M    M
 22000  -28.4 -19.1   195   40   21   8.8   4.8   16.7  62.0    11.2      M    M
 21000  -25.8 -14.4   195   42   22   8.4   4.6   16.4  61.6    11.1      M    M
 20000  -23.5 -10.3   195   44   23   7.6   4.2   15.6  60.1    10.5      M    M
 19500  -22.4  -8.3   190   46   24   7.6   4.2   15.3  59.5    10.2      M    M
 19000  -21.3  -6.3   190   47   24   7.6   4.2   14.9  58.9    10.0      M    M
 18500  -20.2  -4.4   190   49   25   7.5   4.1   14.6  58.3     9.7      M    M
 18000  -19.1  -2.4   185   50   26   6.6   3.6   14.1  57.5     9.3      M    M
 17500  -18.1  -0.6   185   51   26   6.7   3.7   13.6  56.5     8.9      M    M
 17000  -17.1   1.2   180   51   26   7.3   4.0   13.2  55.7     8.5      M    M
 16500  -16.0   3.2   175   48   25   7.4   4.1   12.8  55.0     8.2      M    M
 16000  -15.0   5.0   170   46   24   7.2   3.9   12.4  54.3     7.9      M    M
 15500  -14.0   6.8   165   42   22   6.8   3.8   11.9  53.4     7.5      M    M
 15000  -13.0   8.6   155   39   20   6.7   3.7   11.4  52.6     7.0      M    M
 14500  -12.1  10.2   150   36   19   4.9   2.7   10.8  51.4     6.5      M    M
 14000  -11.0  12.2   135   32   17   5.2   2.9    9.6  49.3     5.4      M    M
 13500  -10.2  13.6   135   30   16   5.4   3.0    8.9  48.0     4.8      M    M
 13000   -9.4  15.1   135   29   15   6.1   3.4    8.2  46.8     4.2      M    M
 12500   -8.3  17.1   135   27   14   7.6   4.1    7.8  46.1     3.8      M    M
 12000   -7.3  18.9   135   25   13   6.7   3.7    7.4  45.3     3.4      M    M
 11750   -6.8  19.8   135   23   12   7.6   4.1    7.2  44.9     3.2      M    M
 11500   -6.2  20.8   135   22   11   7.6   4.2    7.0  44.6     3.1      M    M
 11250   -5.7  21.7   135   21   11   7.7   4.2    6.8  44.3     2.9      M    M
 11000   -5.1  22.8   130   19   10   7.0   3.8    6.7  44.0     2.7      M    M
 10750   -4.6  23.7   130   17    9   6.7   3.7    6.4  43.6     2.5      M    M
 10500   -4.1  24.6   130   15    8   6.9   3.8    6.2  43.1     2.3      M    M
 10250   -3.6  25.5   125   13    7   7.3   4.0    6.0  42.8     2.0      M    M
 10000   -3.1  26.4   120   11    6   5.6   3.0    5.8  42.4     1.8      M    M
  9750   -2.8  27.0   090    7    4   3.9   2.2    5.3  41.6     1.4      M    M
  9500   -2.5  27.5   060    6    3   4.5   2.5    4.9  40.9     1.0      M    M
  9250   -2.2  28.0   030    8    4   4.3   2.4    4.5  40.1     0.6      M    M
  9000   -2.0  28.4   010   10    5   1.1   0.6    4.0  39.2     0.1      M    M
  8750   -2.0  28.4   360   14    7  -0.7  -0.4    3.2  37.8    -0.7    180  0.9
  8500   -2.0  28.4   350   17    9   0.1   0.1    2.5  36.5    -1.5    173  0.9
  8250   -2.0  28.4   345   20   11   0.5   0.3    1.8  35.2    -2.2    165  0.8
  8000   -2.0  28.4   340   21   11   1.0   0.6    1.1  34.0    -2.9    156  0.8
  7750   -1.8  28.8   335   21   11   3.0   1.7    0.5  32.9    -3.5    145  0.7
  7500   -1.5  29.3   330   19   10   5.7   3.1    0.1  32.2    -3.9    127  0.6
  7250   -1.1  30.0   330   18    9   4.9   2.7   -0.1  31.8    -4.1    108  0.5
  7000   -0.8  30.6   330   16    8   3.6   1.9    0.0  32.1    -4.0     91  0.5
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           04/16/2015 at 0900 MDT          |       04/16/2015 at 1200 MDT
                                           |
K index... +18.2  LI... +272.8             | K index... +17.8  LI... +272.0
CAPE... +24.2  CIN... -3.3                 | CAPE... +73.8  CIN... -10.4
                                           |
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 -56.2 -69.2  240  16  8   3.7   2.0 | -56.1 -69.0  240  18  9   3.7   2.0
 45000 -50.7 -59.3  255  26 13   2.8   1.5 | -50.5 -58.9  250  23 12   1.2   0.7
 40000 -49.6 -57.3  200  26 13   0.6   0.3 | -48.7 -55.7  205  32 16   1.2   0.7
 38000 -49.6 -57.3  195  32 17  -0.7  -0.4 | -48.4 -55.1  200  37 19  -0.5  -0.3
 36000 -50.0 -58.0  200  41 21  -0.7  -0.4 | -48.6 -55.5  200  42 22  -0.5  -0.3
 34000 -50.4 -58.7  205  50 26   0.5   0.3 | -48.9 -56.0  200  46 24   0.5   0.3
 32000 -49.4 -56.9  195  56 29   1.7   1.0 | -48.0 -54.4  195  57 29   1.5   0.8
 30000 -48.3 -54.9  185  64 33   5.5   3.0 | -46.7 -52.1  190  68 35   6.3   3.5
 29000 -45.9 -50.6  185  61 31   8.0   4.4 | -45.0 -49.0  185  68 35   5.8   3.2
 28000 -42.9 -45.2  180  58 30   8.0   4.4 | -43.2 -45.8  185  68 35   5.8   3.2
 27000 -40.5 -40.9  175  55 28   8.0   4.4 | -41.5 -42.7  185  68 35   5.9   3.2
 26000 -38.3 -36.9  175  54 28   7.3   4.0 | -39.1 -38.4  180  66 34   8.6   4.7
 25000 -36.1 -33.0  180  53 27   7.3   4.0 | -36.5 -33.7  180  65 34   8.6   4.7
 24000 -33.9 -29.0  180  52 27   7.2   3.9 | -33.9 -29.0  180  64 33   8.8   4.8
 23000 -31.5 -24.7  180  50 26   8.2   4.5 | -31.6 -24.9  180  60 31   7.1   3.9
 22000 -29.1 -20.4  180  47 24   8.2   4.5 | -29.5 -21.1  180  56 29   7.2   3.9
 21000 -26.7 -16.1  180  45 23   8.0   4.4 | -27.4 -17.3  180  51 26   7.4   4.0
 20000 -24.4 -11.9  180  42 21   7.6   4.2 | -25.1 -13.2  180  47 24   7.8   4.3
 19500 -23.3  -9.9  175  40 21   7.6   4.2 | -23.9 -11.0  180  45 23   7.8   4.3
 19000 -22.1  -7.8  175  38 20   7.7   4.2 | -22.8  -9.0  180  43 22   7.8   4.3
 18500 -21.0  -5.8  175  36 19   7.7   4.2 | -21.6  -6.9  175  41 21   8.0   4.4
 18000 -19.8  -3.6  175  35 18   8.0   4.4 | -20.4  -4.7  175  39 20   8.8   4.8
 17500 -18.6  -1.5  170  33 17   8.0   4.4 | -19.1  -2.4  175  36 19   8.8   4.8
 17000 -17.4   0.7  170  32 17   8.1   4.4 | -17.8  -0.0  175  35 18   8.5   4.7
 16500 -16.3   2.7  170  31 16   8.1   4.4 | -16.5   2.3  170  33 17   8.5   4.7
 16000 -15.1   4.8  170  30 15   7.7   4.2 | -15.2   4.6  170  32 17   8.3   4.6
 15500 -14.0   6.8  170  29 15   7.4   4.1 | -14.0   6.8  170  32 16   8.1   4.5
 15000 -12.9   8.8  170  29 15   7.3   4.0 | -12.8   9.0  170  31 16   8.1   4.4
 14500 -11.9  10.6  165  27 14   7.0   3.8 | -11.0  12.2  165  30 16   7.8   4.3
 14000 -10.4  13.3  160  25 13   7.6   4.2 |  -9.9  14.2  165  30 15   6.2   3.4
 13500  -9.2  15.4  155  24 12   7.9   4.4 |  -9.2  15.4  165  29 15   5.5   3.0
 13000  -8.1  17.4  145  22 12   7.6   4.2 |  -8.5  16.7  165  28 14   6.7   3.7
 12500  -7.0  19.4  140  22 11   7.2   4.0 |  -7.4  18.7  160  26 13   7.7   4.2
 12000  -5.9  21.4  125  21 11   7.7   4.2 |  -6.2  20.8  160  24 12   7.7   4.2
 11750  -5.3  22.5  120  21 11   8.9   4.9 |  -5.8  21.6  155  22 12   4.8   2.6
 11500  -4.6  23.7  120  21 11   8.7   4.8 |  -5.4  22.3  150  22 11   5.2   2.9
 11250  -3.9  25.0  115  21 11   9.3   5.1 |  -5.0  23.0  145  21 11   5.2   2.9
 11000  -3.3  26.1  110  21 11   7.0   3.9 |  -4.6  23.7  140  20 10   4.9   2.7
 10750  -2.9  26.8  100  20 10   4.6   2.5 |  -4.3  24.3  130  19 10   5.3   2.9
 10500  -2.6  27.3  095  19 10   4.7   2.6 |  -3.9  25.0  125  18  9   5.9   3.2
 10250  -2.2  28.0  085  20 10   5.6   3.1 |  -3.4  25.9  115  18  9   5.9   3.3
 10000  -1.9  28.6  075  20 10   1.0   0.6 |  -3.0  26.6  105  18  9   4.4   2.4
  9750  -2.1  28.2  060  21 11  -2.2  -1.2 |  -2.8  27.0  095  18  9   2.2   1.2
  9500  -2.2  28.0  050  22 11  -0.1  -0.0 |  -2.7  27.1  085  18  9   2.1   1.1
  9250  -2.3  27.9  040  24 12  -0.7  -0.4 |  -2.5  27.5  075  19 10   1.7   0.9
  9000  -2.4  27.7  035  25 13  -2.7  -1.5 |  -2.5  27.5  060  19 10  -1.3  -0.7
  8750  -2.6  27.3  025  26 13  -2.6  -1.4 |  -2.6  27.3  050  18  9  -0.3  -0.1
  8500  -2.8  27.0  020  26 13  -2.2  -1.2 |  -2.5  27.5  035  17  9   0.9   0.5
  8250  -2.9  26.8  010  26 13   0.8   0.5 |  -2.4  27.7  025  16  8   4.3   2.3
  8000  -2.6  27.3  005  25 13   6.0   3.3 |  -1.8  28.8  015  15  8   9.8   5.4
  7750  -2.1  28.2  360  23 12   7.0   3.8 |  -1.1  30.0  015  14  7   8.9   4.9
  7500  -1.5  29.3  355  20 11   7.8   4.3 |  -0.5  31.1  010  13  7   8.4   4.6
  7250  -0.9  30.4  355  18  9   8.7   4.8 |   0.2  32.4  010  12  6   9.7   5.3
  7000  -0.2  31.6  350  17  9   9.9   5.4 |   1.0  33.8  010  11  6  11.2   6.1
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/16/2015 at 1500 MDT          |       04/16/2015 at 1800 MDT
                                           |
K index... +6.1  LI... +274.0              | K index... +22.2  LI... +273.7
CAPE... +11.4  CIN... -0.8                 | CAPE... 0.0  CIN... -0.4
                                           |
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 -56.0 -68.8  245  18  9   3.4   1.9 | -57.2 -71.0  250  17  9   3.9   2.1
 45000 -50.8 -59.4  235  22 11   1.4   0.8 | -51.2 -60.2  220  18  9   1.1   0.6
 40000 -48.7 -55.7  205  32 17   1.4   0.8 | -49.3 -56.7  195  29 15   1.2   0.7
 38000 -48.2 -54.8  205  36 19   0.3   0.2 | -48.7 -55.7  195  32 16   1.0   0.5
 36000 -48.0 -54.4  210  39 20   0.3   0.2 | -48.1 -54.6  200  33 17   1.0   0.5
 34000 -47.8 -54.0  210  42 21   0.3   0.2 | -47.5 -53.5  205  34 18   0.9   0.5
 32000 -47.6 -53.7  205  53 27   0.3   0.2 | -46.9 -52.4  205  43 22   0.9   0.5
 30000 -47.0 -52.6  200  62 32   7.1   3.9 | -46.1 -51.0  200  50 26   5.7   3.1
 29000 -45.1 -49.2  200  65 33   6.4   3.5 | -44.5 -48.1  200  49 25   5.1   2.8
 28000 -43.1 -45.6  200  68 35   6.4   3.5 | -43.0 -45.4  200  49 25   5.1   2.8
 27000 -41.2 -42.2  195  70 36   6.4   3.5 | -41.4 -42.5  195  48 25   5.4   2.9
 26000 -38.9 -38.0  195  68 35   7.9   4.4 | -39.1 -38.4  195  47 24   8.5   4.7
 25000 -36.6 -33.9  195  64 33   7.9   4.4 | -36.5 -33.7  190  45 23   8.5   4.7
 24000 -34.2 -29.6  195  60 31   7.9   4.4 | -34.0 -29.2  185  44 23   8.6   4.7
 23000 -31.8 -25.2  190  57 29   8.0   4.4 | -31.4 -24.5  185  46 24   8.5   4.6
 22000 -29.4 -20.9  190  54 28   8.0   4.4 | -28.9 -20.0  180  50 26   8.5   4.7
 21000 -27.0 -16.6  185  51 26   8.2   4.5 | -26.4 -15.5  180  53 27   8.4   4.6
 20000 -24.5 -12.1  185  48 25   8.4   4.6 | -23.9 -11.0  180  51 26   8.2   4.5
 19500 -23.3  -9.9  180  46 24   8.4   4.6 | -22.7  -8.9  180  50 26   8.2   4.5
 19000 -22.0  -7.6  180  45 23   8.4   4.6 | -21.5  -6.7  175  49 25   8.2   4.5
 18500 -20.7  -5.3  180  43 22   8.2   4.5 | -20.3  -4.5  175  48 25   8.1   4.5
 18000 -19.6  -3.3  180  41 21   7.6   4.2 | -19.1  -2.4  175  45 23   7.7   4.2
 17500 -18.4  -1.1  175  39 20   7.6   4.2 | -18.0  -0.4  175  43 22   7.8   4.3
 17000 -17.2   1.0  175  37 19   8.0   4.4 | -16.9   1.6  170  40 21   7.3   4.0
 16500 -16.0   3.2  180  35 18   8.0   4.4 | -15.8   3.6  170  37 19   7.3   4.0
 16000 -14.8   5.4  180  33 17   8.0   4.4 | -14.7   5.5  165  35 18   7.1   3.9
 15500 -13.0   8.6  180  30 16   7.9   4.4 | -13.2   8.2  165  32 17   7.0   3.9
 15000 -11.8  10.8  180  29 15   8.9   4.9 | -12.2  10.0  160  31 16   6.7   3.7
 14500 -10.4  13.3  175  28 14   9.0   4.9 | -11.2  11.8  160  29 15   6.7   3.7
 14000  -9.1  15.6  175  27 14   8.4   4.6 | -10.2  13.6  155  27 14   6.8   3.8
 13500  -7.9  17.8  175  26 13   8.0   4.4 |  -9.2  15.4  150  25 13   7.0   3.8
 13000  -6.6  20.1  175  25 13   6.9   3.8 |  -8.1  17.4  145  23 12   7.7   4.2
 12500  -5.8  21.6  170  25 13   6.2   3.4 |  -6.9  19.6  145  22 11   8.9   4.9
 12000  -5.1  22.8  165  25 13   3.0   1.6 |  -6.1  21.0  140  20 10   4.2   2.3
 11750  -5.1  22.8  165  23 12   0.3   0.2 |  -5.6  21.9  140  19 10   6.9   3.8
 11500  -5.1  22.8  165  20 10   1.0   0.6 |  -5.1  22.8  135  18  9   6.3   3.5
 11250  -5.1  22.8  160  18  9   0.0   0.0 |  -4.7  23.5  135  17  9   6.4   3.5
 11000  -5.1  22.8  160  15  8  -0.3  -0.1 |  -4.2  24.4  130  15  8   6.1   3.3
 10750  -5.1  22.8  150  13  7   3.6   2.0 |  -3.8  25.2  130  14  7   5.9   3.2
 10500  -4.7  23.5  145  11  6   5.8   3.2 |  -3.3  26.1  125  12  6   6.0   3.3
 10250  -4.4  24.1  130  10  5   5.1   2.8 |  -2.9  26.8  115  11  6   6.0   3.3
 10000  -4.0  24.8  120  10  5   6.5   3.6 |  -2.5  27.5  110  10  5   3.2   1.8
  9750  -3.5  25.7  110  10  5   8.1   4.4 |  -2.4  27.7  095   9  5   2.3   1.3
  9500  -2.9  26.8  100  11  5   8.4   4.6 |  -2.2  28.0  080   9  5   3.5   1.9
  9250  -2.3  27.9  095  11  6   8.1   4.4 |  -2.0  28.4  070  10  5   3.8   2.1
  9000  -1.7  28.9  085  11  6   7.2   3.9 |  -1.7  28.9  055  10  5   5.8   3.2
  8750  -1.2  29.8  075  10  5   6.9   3.8 |  -1.2  29.8  040  10  5   6.8   3.8
  8500  -0.7  30.7  055   9  5   6.6   3.6 |  -0.7  30.7  025  11  6   6.3   3.4
  8250  -0.3  31.5  040   9  5   8.3   4.5 |  -0.2  31.6  010  12  6   8.0   4.4
  8000   0.5  32.9  035   9  5  10.7   5.9 |   0.5  32.9  005  13  7  10.2   5.6
  7750   1.3  34.3  030   9  4   9.8   5.4 |   1.2  34.2  005  13  7   9.6   5.3
  7500   1.9  35.4  030   8  4   9.2   5.1 |   1.9  35.4  360  13  7   9.3   5.1
  7250   2.7  36.9  030   8  4  10.6   5.8 |   2.6  36.7  360  13  6   9.7   5.3
  7000   3.5  38.3  030   8  4  11.9   6.5 |   3.3  37.9  360  12  6  10.1   5.5
  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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