Soaring Guidance
Issued by NWS Pueblo, CO

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125
UXUS97 KPUB 241137
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0437 MST Tuesday, January 24, 2017

This forecast is for Tuesday, January 24, 2017:

If the trigger temperature of 36.5 F/2.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7337 ft MSL (166 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 Wednesday 01/25.... Fair

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

Remarks...

Sunrise/Sunset.................... 07:11:08 / 17:10:19 MST
Total possible sunshine........... 9 hr 59 min 11 sec (599 min 11 sec)
Altitude of sun at 12:11:07 MST... 32.09 degrees

Upper air data from numerical model forecast valid on 01/24/2017 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 14630 ft MSL (7459 ft AGL)
Lifted condensation level....... 12203 ft MSL (5032 ft AGL)
Lifted index.................... +7.7
K index......................... +5.9

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  -53.7 -64.7   240   41   21   2.4   1.3      M     M       M      M    M
 45000  -50.2 -58.4   235   62   32   2.4   1.3      M     M       M      M    M
 40000  -48.5 -55.3   235   70   36   0.8   0.5      M     M       M      M    M
 38000  -48.0 -54.4   235   73   38   1.0   0.5      M     M       M      M    M
 36000  -47.4 -53.3   240   80   41   1.0   0.6      M     M       M      M    M
 34000  -46.8 -52.2   245   87   45   1.0   0.5      M     M       M      M    M
 32000  -45.9 -50.6   245   89   46   1.7   0.9      M     M       M      M    M
 30000  -44.9 -48.8   245   90   46   1.7   0.9      M     M       M      M    M
 29000  -44.4 -47.9   245   88   45   1.2   0.7   24.6  76.2    19.7      M    M
 28000  -44.1 -47.4   245   82   42   1.3   0.7   21.1  70.0    17.3      M    M
 27000  -43.7 -46.7   245   76   39   1.3   0.7   17.9  64.1    15.0      M    M
 26000  -43.2 -45.8   240   68   35   3.3   1.8   14.1  57.4    12.2      M    M
 25000  -41.7 -43.1   235   62   32   4.8   2.7   12.1  53.8    10.7      M    M
 24000  -40.3 -40.5   230   57   30   4.9   2.7   10.3  50.5     9.4      M    M
 23000  -38.8 -37.8   220   54   28   7.0   3.8    8.7  47.6     8.1      M    M
 22000  -36.2 -33.2   225   52   27   8.6   4.7    8.2  46.7     7.8      M    M
 21000  -33.6 -28.5   230   51   26   8.7   4.8    7.8  46.1     7.6      M    M
 20000  -31.1 -24.0   235   48   25   7.6   4.2    7.4  45.3     7.3      M    M
 19500  -30.0 -22.0   240   45   23   7.7   4.2    7.0  44.6     7.0      M    M
 19000  -28.8 -19.8   240   41   21   7.7   4.2    6.6  43.9     6.7      M    M
 18500  -27.7 -17.9   245   38   20   7.7   4.2    6.3  43.3     6.4      M    M
 18000  -26.5 -15.7   250   35   18   7.6   4.2    6.0  42.8     6.2      M    M
 17500  -25.2 -13.4   255   33   17   9.8   5.4    5.9  42.5     6.1      M    M
 17000  -23.8 -10.8   255   32   16   9.6   5.3    5.8  42.5     6.1      M    M
 16500  -22.3  -8.1   255   30   15   9.3   5.1    5.8  42.4     6.1      M    M
 16000  -21.0  -5.8   255   28   14   9.2   5.1    5.7  42.3     6.1      M    M
 15500  -19.6  -3.3   255   26   13   9.0   5.0    5.6  42.1     6.0      M    M
 15000  -18.3  -0.9   255   23   12   8.6   4.7    5.4  41.8     5.9      M    M
 14500  -17.0   1.4   255   20   10   8.5   4.7    5.3  41.5     5.7      M    M
 14000  -15.8   3.6   255   17    9   7.5   4.1    5.0  40.9     5.4      M    M
 13500  -14.7   5.5   255   14    7   7.6   4.2    4.6  40.3     5.1      M    M
 13000  -13.6   7.5   265   14    7   7.1   3.9    4.2  39.6     4.8      M    M
 12500  -12.5   9.5   275   16    8   7.4   4.1    3.8  38.9     4.4      M    M
 12000  -11.6  11.1   285   18    9   6.8   3.7    3.3  38.0     4.0      M    M
 11750  -11.0  12.2   285   18    9   8.2   4.5    3.2  37.7     3.9      M    M
 11500  -10.4  13.3   290   19   10   8.0   4.4    3.0  37.4     3.7      M    M
 11250   -9.8  14.4   295   19   10   7.4   4.1    2.9  37.2     3.6      M    M
 11000   -9.2  15.4   295   19   10   7.7   4.2    2.7  36.8     3.4      M    M
 10750   -8.6  16.5   300   18    9   9.8   5.4    2.6  36.7     3.4      M    M
 10500   -7.8  18.0   300   16    8  10.4   5.7    2.6  36.8     3.4      M    M
 10250   -7.1  19.2   300   15    8   9.8   5.4    2.7  36.8     3.4      M    M
 10000   -5.7  21.7   305   14    7   9.6   5.3    2.6  36.7     3.4      M    M
  9750   -5.0  23.0   305   13    7   9.8   5.4    2.6  36.7     3.4      M    M
  9500   -4.3  24.3   305   12    6   9.6   5.3    2.6  36.7     3.4      M    M
  9250   -3.5  25.7   310   12    6   9.6   5.3    2.6  36.7     3.3      M    M
  9000   -2.8  27.0   310   11    6   9.4   5.2    2.6  36.7     3.3      M    M
  8750   -2.2  28.0   315   11    6   7.9   4.3    2.5  36.5     3.3      M    M
  8500   -1.7  28.9   315   11    6   6.6   3.6    2.3  36.2     3.0      M    M
  8250   -1.2  29.8   320   11    5   6.1   3.3    2.1  35.7     2.8      M    M
  8000   -0.8  30.6   325   10    5   7.6   4.2    1.8  35.3     2.5      M    M
  7750   -0.4  31.3   325   10    5  -1.2  -0.6    1.5  34.7     2.1      M    M
  7500   -1.3  29.7   325    8    4 -19.7 -10.8   -0.1  31.9     0.5      M    M
  7250   -2.2  28.0   325    6    3  13.8   7.6   -1.6  29.1    -1.1      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 * * * * * *

           01/24/2017 at 0800 MST          |       01/24/2017 at 1100 MST
                                           |
K index... -0.5  LI... -0.9                | K index... -8.4  LI... -1.0
CAPE... +75.8  CIN... -59.9                | CAPE... +96.9  CIN... -49.8
                                           |
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  230  47 24   1.7   0.9 | -51.1 -60.0  235  48 24   1.5   0.8
 45000 -49.9 -57.8  230  65 33   1.7   0.9 | -48.9 -56.0  235  62 32   1.5   0.8
 40000 -48.4 -55.1  235  69 35   0.8   0.4 | -47.8 -54.0  235  67 34   0.6   0.3
 38000 -47.9 -54.2  240  69 36   1.7   0.9 | -47.4 -53.3  240  68 35   1.6   0.9
 36000 -46.8 -52.2  240  73 38   1.8   1.0 | -46.2 -51.2  240  68 35   1.9   1.0
 34000 -45.7 -50.3  245  78 40   1.8   1.0 | -45.1 -49.2  240  69 36   1.9   1.0
 32000 -44.5 -48.1  245  79 40   2.0   1.1 | -44.2 -47.6  245  68 35   1.3   0.7
 30000 -43.3 -45.9  245  77 40   2.0   1.1 | -43.4 -46.1  245  65 33   1.3   0.7
 29000 -42.8 -45.0  245  76 39   1.7   0.9 | -43.0 -45.4  245  63 33   0.5   0.3
 28000 -42.3 -44.1  245  71 36   1.6   0.9 | -43.0 -45.4  245  59 30   0.2   0.1
 27000 -41.8 -43.2  245  65 34   1.6   0.9 | -43.0 -45.4  250  55 28   0.2   0.1
 26000 -41.2 -42.2  245  59 30   1.1   0.6 | -42.9 -45.2  250  51 26   0.1   0.1
 25000 -41.2 -42.2  240  54 28  -0.3  -0.2 | -42.8 -45.0  250  44 23   0.5   0.2
 24000 -41.3 -42.3  240  49 25  -0.3  -0.2 | -42.6 -44.7  250  38 20   0.5   0.3
 23000 -41.4 -42.5  235  44 22   1.6   0.9 | -42.5 -44.5  250  32 16   2.0   1.1
 22000 -39.3 -38.7  240  41 21   8.0   4.4 | -40.2 -40.4  255  30 16   8.6   4.7
 21000 -36.9 -34.4  245  38 20   8.0   4.4 | -37.7 -35.9  260  29 15   8.6   4.7
 20000 -34.5 -30.1  250  35 18   9.0   4.9 | -35.1 -31.2  265  28 14   9.0   5.0
 19500 -33.1 -27.6  250  34 17   9.0   4.9 | -33.7 -28.7  265  26 14   9.1   5.0
 19000 -31.8 -25.2  255  32 16   9.0   4.9 | -32.4 -26.3  265  25 13   9.1   5.0
 18500 -30.4 -22.7  255  30 16   9.0   4.9 | -31.0 -23.8  265  24 12   9.0   5.0
 18000 -29.1 -20.4  260  29 15   8.9   4.9 | -29.6 -21.3  265  22 11   9.0   4.9
 17500 -27.7 -17.9  260  27 14   9.6   5.3 | -28.3 -18.9  265  21 11   9.6   5.3
 17000 -26.3 -15.3  260  25 13   9.6   5.3 | -26.8 -16.2  265  21 11   9.6   5.3
 16500 -24.8 -12.6  260  23 12   9.6   5.3 | -25.4 -13.7  265  21 11   9.5   5.2
 16000 -23.4 -10.1  260  22 11   9.6   5.3 | -24.0 -11.2  265  21 11   9.5   5.2
 15500 -21.9  -7.4  260  21 11   9.6   5.3 | -22.6  -8.7  265  20 10   9.5   5.2
 15000 -20.5  -4.9  260  20 11   9.6   5.2 | -21.1  -6.0  265  20 10   9.5   5.2
 14500 -19.1  -2.4  255  20 10   9.6   5.3 | -19.7  -3.5  265  20 10   9.5   5.2
 14000 -17.7   0.1  255  20 10   9.4   5.2 | -18.3  -0.9  265  20 10   9.1   5.0
 13500 -16.3   2.7  250  20 10   9.5   5.2 | -17.0   1.4  265  19 10   9.2   5.1
 13000 -14.9   5.2  250  19 10   8.9   4.9 | -15.7   3.7  270  19 10   8.4   4.6
 12500 -13.6   7.5  255  19 10   9.5   5.2 | -14.4   6.1  275  19 10   9.1   5.0
 12000 -12.6   9.3  255  19 10   6.6   3.6 | -13.5   7.7  280  20 10   6.2   3.4
 11750 -11.9  10.6  260  19 10   9.7   5.3 | -12.8   9.0  280  20 10   9.7   5.3
 11500 -11.2  11.8  265  19 10   9.3   5.1 | -12.1  10.2  285  20 11   9.2   5.1
 11250 -10.5  13.1  265  19 10   7.8   4.3 | -11.5  11.3  285  21 11   7.7   4.2
 11000 -10.0  14.0  270  18  9   6.2   3.4 | -11.0  12.2  290  21 11   6.0   3.3
 10750  -9.5  14.9  270  17  9   8.2   4.5 | -10.5  13.1  295  21 11   7.6   4.2
 10500  -8.9  16.0  275  16  8   8.9   4.9 |  -9.9  14.2  300  21 11   8.3   4.6
 10250  -8.2  17.2  280  14  7   8.7   4.8 |  -9.3  15.3  305  21 11   7.8   4.3
 10000  -7.0  19.4  285  12  6   8.6   4.7 |  -8.8  16.2  305  21 11   7.3   4.0
  9750  -6.3  20.7  285  11  5   8.4   4.6 |  -7.7  18.1  310  20 10   8.0   4.4
  9500  -5.7  21.7  290   9  5   7.8   4.3 |  -7.1  19.2  315  19 10   7.6   4.2
  9250  -5.2  22.6  295   9  5   7.3   4.0 |  -6.6  20.1  320  19 10   7.2   3.9
  9000  -4.7  23.5  300   9  5   7.8   4.3 |  -6.0  21.2  320  18  9   7.8   4.3
  8750  -4.1  24.6  305   9  5   6.9   3.8 |  -5.4  22.3  325  17  9   9.3   5.1
  8500  -3.7  25.3  305  10  5   4.5   2.5 |  -4.7  23.5  325  16  8   9.5   5.2
  8250  -3.4  25.9  310  11  6   3.9   2.1 |  -4.0  24.8  330  15  8   9.1   5.0
  8000  -3.2  26.2  315  12  6   3.4   1.9 |  -3.4  25.9  335  15  7   9.3   5.1
  7750  -3.0  26.6  315  14  7   0.8   0.4 |  -2.6  27.3  340  14  7  13.7   7.5
  7500  -3.1  26.4  320  11  6  -1.2  -0.7 |  -1.3  29.7  340  13  7  20.9  11.5
  7250  -3.1  26.4  330   9  4   2.8   1.6 |   0.0  32.0  345  12  6   8.2   4.5
  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

           01/24/2017 at 1400 MST          |       01/24/2017 at 1700 MST
                                           |
K index... +2.2  LI... -1.1                | K index... +13.2  LI... -0.1
CAPE... +123.1  CIN... -5.3                | CAPE... +20.0  CIN... -2.2
                                           |
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 -51.4 -60.5  240  47 24   1.6   0.9 | -51.7 -61.1  240  42 22   1.1   0.6
 45000 -49.1 -56.4  235  60 31   1.6   0.9 | -50.0 -58.0  240  54 28   1.1   0.6
 40000 -47.1 -52.8  240  63 33   1.3   0.7 | -47.0 -52.6  245  58 30   2.1   1.2
 38000 -46.2 -51.2  245  64 33   1.1   0.6 | -45.7 -50.3  245  59 31   1.9   1.1
 36000 -45.6 -50.1  245  67 34   1.0   0.5 | -45.4 -49.7  250  61 32   0.4   0.2
 34000 -45.0 -49.0  245  69 35   1.0   0.5 | -45.1 -49.2  250  63 33   0.4   0.2
 32000 -44.3 -47.7  250  67 35   1.3   0.7 | -44.9 -48.8  250  62 32   0.2   0.1
 30000 -43.6 -46.5  250  63 32   1.3   0.7 | -44.8 -48.6  250  59 30   0.2   0.1
 29000 -43.2 -45.8  250  60 31  -0.8  -0.4 | -44.7 -48.5  255  57 30  -1.8  -1.0
 28000 -43.8 -46.8  250  56 29  -1.9  -1.0 | -45.6 -50.1  250  52 27  -3.0  -1.6
 27000 -44.4 -47.9  250  51 26  -1.9  -1.0 | -46.5 -51.7  250  47 24  -3.0  -1.6
 26000 -44.9 -48.8  255  46 24  -2.0  -1.1 | -47.4 -53.3  250  42 22  -3.5  -1.9
 25000 -44.6 -48.3  250  41 21   3.0   1.7 | -46.7 -52.1  250  38 20   5.7   3.1
 24000 -43.4 -46.1  245  34 18   3.1   1.7 | -44.9 -48.8  255  35 18   5.8   3.2
 23000 -42.5 -44.5  240  29 15   4.3   2.4 | -42.7 -44.9  255  32 16   6.8   3.7
 22000 -40.0 -40.0  245  28 14   9.2   5.0 | -40.1 -40.2  260  29 15   9.2   5.0
 21000 -37.2 -35.0  250  27 14   9.2   5.0 | -37.4 -35.3  260  26 13   9.2   5.0
 20000 -34.5 -30.1  255  26 14   8.2   4.5 | -34.7 -30.5  265  23 12   8.4   4.6
 19500 -33.3 -27.9  260  23 12   8.2   4.5 | -33.4 -28.1  275  22 11   8.4   4.6
 19000 -32.1 -25.8  260  21 11   8.2   4.5 | -32.2 -26.0  280  21 11   8.4   4.6
 18500 -30.9 -23.6  265  18  9   8.2   4.5 | -30.9 -23.6  290  21 11   8.4   4.6
 18000 -29.6 -21.3  270  15  8   8.2   4.5 | -29.6 -21.3  295  21 11   8.5   4.6
 17500 -28.4 -19.1  275  14  7   8.0   4.4 | -28.4 -19.1  300  22 11   8.4   4.6
 17000 -27.2 -17.0  285  15  7   8.0   4.4 | -27.1 -16.8  305  22 11   8.4   4.6
 16500 -26.0 -14.8  290  15  8   8.4   4.6 | -25.9 -14.6  305  23 12   8.4   4.6
 16000 -24.8 -12.6  295  16  8   8.6   4.7 | -24.7 -12.5  305  23 12   8.3   4.6
 15500 -23.5 -10.3  295  17  9   8.7   4.8 | -23.4 -10.1  305  22 11   8.3   4.6
 15000 -22.2  -8.0  300  18  9   8.9   4.9 | -22.2  -8.0  305  22 11   8.3   4.6
 14500 -20.8  -5.4  300  18  9   8.9   4.9 | -21.0  -5.8  310  22 11   8.3   4.5
 14000 -19.5  -3.1  305  19 10   8.8   4.8 | -19.8  -3.6  310  22 12   7.9   4.3
 13500 -18.2  -0.8  305  20 10   8.8   4.8 | -18.6  -1.5  310  23 12   7.9   4.3
 13000 -16.9   1.6  310  21 11   8.7   4.8 | -17.4   0.7  315  23 12   8.0   4.4
 12500 -15.6   3.9  315  21 11   9.4   5.2 | -16.3   2.7  315  23 12   8.5   4.7
 12000 -14.7   5.5  320  21 11   6.5   3.6 | -15.4   4.3  315  23 12   5.9   3.2
 11750 -13.9   7.0  320  21 11  10.7   5.9 | -14.8   5.4  320  23 12   9.2   5.1
 11500 -13.2   8.2  325  21 11  10.1   5.5 | -14.1   6.6  320  23 12   8.5   4.7
 11250 -12.5   9.5  325  21 11   8.5   4.6 | -13.5   7.7  320  23 12   7.5   4.1
 11000 -12.0  10.4  330  21 11   6.9   3.8 | -13.0   8.6  320  23 12   6.3   3.5
 10750 -11.4  11.5  330  21 11   9.0   5.0 | -12.5   9.5  325  23 12   7.5   4.1
 10500 -10.7  12.7  330  21 11  10.1   5.6 | -11.9  10.6  325  22 12   8.0   4.4
 10250 -10.0  14.0  335  21 11   8.3   4.6 | -11.4  11.5  330  22 11   7.3   4.0
 10000  -9.4  15.1  335  21 11   6.6   3.6 | -10.9  12.4  330  21 11   6.9   3.8
  9750  -8.3  17.1  340  20 10   9.4   5.2 | -10.4  13.3  335  21 11   7.3   4.0
  9500  -7.6  18.3  340  19 10   9.3   5.1 |  -9.2  15.4  345  20 10   8.5   4.7
  9250  -6.9  19.6  345  18  9   9.3   5.1 |  -8.6  16.5  345  19 10   8.6   4.7
  9000  -6.2  20.8  345  17  9   9.3   5.1 |  -7.9  17.8  350  18  9   8.9   4.9
  8750  -5.6  21.9  350  16  8   9.7   5.3 |  -7.3  18.9  355  18  9   9.8   5.4
  8500  -4.8  23.4  350  16  8  10.3   5.7 |  -6.5  20.3  360  17  9   9.9   5.4
  8250  -4.0  24.8  350  15  8  10.3   5.6 |  -5.8  21.6  360  17  9   9.9   5.4
  8000  -3.3  26.1  350  15  8  10.7   5.9 |  -5.1  22.8  360  17  9   9.5   5.2
  7750  -2.4  27.7  355  15  8  14.9   8.2 |  -4.4  24.1  360  16  8  10.5   5.8
  7500  -1.0  30.2  355  14  7  20.0  11.0 |  -3.5  25.7  360  13  7  13.5   7.4
  7250   0.3  32.5  355  12  6  11.4   6.2 |  -2.6  27.3  005  11  6   7.9   4.3
  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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