Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 290120
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1820 MST Wednesday, January 28, 2015

This forecast is for Thursday, January 29, 2015:

If the trigger temperature of 43.6 F/6.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 9899 ft MSL (4612 ft AGL)

Forecast maximum temperature................... 46.0 F/8.2 C
Time of trigger temperature.................... 1230 MST
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................. 8466 ft MSL (3178 ft AGL)
Thermal soaring outlook for Friday 01/30....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 35026 ft MSL (29739 ft AGL)
Wave soaring outlook for Friday 01/30.......... Poor

Remarks... Moderate west to northwest flow aloft. Surface high pressure building
           region from the north along with cooler temperatures.

Sunrise/Sunset.................... 07:10:04 / 17:14:10 MST
Total possible sunshine........... 10 hr 4 min 5 sec (604 min 5 sec)
Altitude of sun at 12:12:29 MST... 32.42 degrees

Upper air data from numerical model forecast valid on 01/29/2015 at 0500 MST

Freezing level.................. 6602 ft MSL (1315 ft AGL)
Convective condensation level... 14678 ft MSL (9391 ft AGL)
Lifted condensation level....... 11651 ft MSL (6364 ft AGL)
Lifted index.................... +10.5
K index......................... +11.4

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  -61.0 -77.8   280   38   19   2.6   1.4      M     M       M      M    M
 45000  -57.2 -71.0   285   49   25   1.2   0.6      M     M       M      M    M
 40000  -56.1 -69.0   280   78   40   0.6   0.4      M     M       M      M    M
 38000  -55.0 -67.0   280   85   44   2.6   1.4      M     M       M      M    M
 36000  -53.5 -64.3   280   89   46   2.6   1.4      M     M       M      M    M
 34000  -51.4 -60.5   280   91   47   6.1   3.3      M     M       M      M    M
 32000  -47.7 -53.9   280   85   44   6.1   3.3      M     M       M      M    M
 30000  -43.8 -46.8   280   79   41   8.4   4.6   33.5  92.2    19.2      M    M
 29000  -40.6 -41.1   280   75   39   8.5   4.7   32.8  91.0    19.0      M    M
 28000  -38.0 -36.4   280   72   37   8.5   4.7   32.3  90.2    18.9      M    M
 27000  -35.7 -32.3   285   67   35   5.8   3.2   31.7  89.1    18.6      M    M
 26000  -33.9 -29.0   285   59   30   5.9   3.2   30.1  86.2    17.6      M    M
 25000  -32.1 -25.8   285   51   26   5.9   3.2   28.7  83.6    16.7      M    M
 24000  -30.3 -22.5   290   43   22   7.1   3.9   27.4  81.3    15.8      M    M
 23000  -28.1 -18.6   290   41   21   7.6   4.2   26.5  79.7    15.3      M    M
 22000  -25.8 -14.4   295   38   20   7.7   4.2   25.8  78.4    14.8      M    M
 21000  -23.6 -10.5   300   35   18   6.4   3.5   25.0  77.0    14.3      M    M
 20000  -21.7  -7.1   300   33   17   6.5   3.6   23.8  74.8    13.5      M    M
 19500  -20.7  -5.3   300   31   16   6.5   3.6   23.2  73.8    13.0      M    M
 19000  -19.7  -3.5   300   30   15   6.6   3.6   22.7  72.8    12.7      M    M
 18500  -18.8  -1.8   305   28   15   6.2   3.4   22.1  71.8    12.3      M    M
 18000  -17.8  -0.0   305   27   14   6.1   3.3   21.5  70.7    11.8      M    M
 17500  -16.9   1.6   305   25   13   5.6   3.1   20.9  69.6    11.3      M    M
 17000  -16.2   2.8   305   24   12   4.8   2.7   20.0  68.1    10.6      M    M
 16500  -15.5   4.1   305   23   12   4.8   2.7   19.2  66.6     9.9      M    M
 16000  -14.8   5.4   305   22   11   4.8   2.7   18.4  65.1     9.2      M    M
 15500  -14.1   6.6   300   22   11   4.8   2.6   17.6  63.6     8.5      M    M
 15000  -13.4   7.9   295   21   11   5.7   3.1   16.8  62.2     7.8      M    M
 14500  -12.1  10.2   295   19   10   5.8   3.2   15.8  60.4     7.0      M    M
 14000  -11.3  11.7   295   18   10   5.9   3.2   15.1  59.3     6.4      M    M
 13500  -10.4  13.3   295   18    9   5.8   3.2   14.5  58.1     5.8      M    M
 13000   -9.4  15.1   295   17    9   7.1   3.9   14.0  57.2     5.3      M    M
 12500   -8.4  16.9   295   17    9   7.1   3.9   13.5  56.3     4.9      M    M
 12000   -7.5  18.5   295   16    8   5.8   3.2   13.0  55.4     4.4      M    M
 11500   -6.6  20.1   295   15    8   6.1   3.3   12.4  54.3     3.8      M    M
 11000   -6.1  21.0   295   14    7   1.3   0.7   11.4  52.5     2.9      M    M
 10500   -5.9  21.4   290   13    7   1.5   0.8   10.1  50.2     1.7      M    M
 10250   -5.9  21.4   290   12    6  -1.1  -0.6    9.4  48.9     1.0      M    M
 10000   -6.0  21.2   290   11    6  -1.0  -0.5    8.5  47.3     0.1      M    M
  9750   -5.9  21.4   295   10    5   3.8   2.1    7.8  46.1    -0.5    305  1.6
  9500   -5.6  21.9   300    8    4   4.0   2.2    7.4  45.3    -0.9    288  1.5
  9250   -5.4  22.3   315    6    3   1.5   0.8    6.8  44.3    -1.4    275  1.4
  9000   -5.2  22.6   340    5    3   1.4   0.7    6.2  43.1    -2.0    263  1.3
  8750   -5.1  22.8   010    5    3   2.6   1.4    5.6  42.0    -2.6    251  1.3
  8500   -4.7  23.5   030    7    3   5.9   3.2    5.1  41.2    -3.0    233  1.2
  8250   -4.2  24.4   030    7    4   7.7   4.2    4.9  40.9    -3.2    209  1.1
  8000   -3.6  25.5   030    7    4   6.8   3.7    4.7  40.5    -3.3    185  0.9
  7750   -3.0  26.6   030    8    4   8.9   4.9    4.6  40.2    -3.5    161  0.8
  7500   -2.3  27.9   030    8    4   9.9   5.4    4.6  40.3    -3.5    130  0.7
  7250   -1.6  29.1   030    8    4   8.8   4.9    4.5  40.1    -3.6    103  0.5
  7000   -0.9  30.4   030    8    4   8.4   4.6    4.5  40.0    -3.6     75  0.4
  6750   -0.4  31.3   025    8    4   7.4   4.1    4.3  39.8    -3.8     50  0.3
  6500    0.2  32.4   015    8    4   7.7   4.2    4.1  39.5    -4.0     27  0.1
  6250    0.7  33.3   005    8    4   7.8   4.3    4.0  39.2    -4.2      3  0.0
  6000    1.3  34.3   360    8    4   7.7   4.2    3.8  38.9    -4.4      M    M
  5750    1.7  35.1   350    7    4   5.1   2.8    3.7  38.6    -4.6      M    M
  5500    1.9  35.4   335    5    2   1.1   0.6    3.2  37.7    -5.2      M    M

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

           01/29/2015 at 0800 MST          |       01/29/2015 at 1100 MST
                                           |
K index... +7.0  LI... +5.3                | K index... -12.1  LI... +5.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.6
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -60.7 -77.3  285  39 20   2.9   1.6 | -61.0 -77.8  290  38 20   2.9   1.6
 45000 -56.4 -69.5  285  49 25   1.1   0.6 | -56.6 -69.9  285  47 24   0.2   0.1
 40000 -55.9 -68.6  280  75 38   0.3   0.2 | -56.0 -68.8  280  67 34   0.4   0.2
 38000 -55.1 -67.2  280  84 43   2.1   1.2 | -55.4 -67.7  280  77 39   1.4   0.8
 36000 -53.8 -64.8  280  93 48   2.1   1.2 | -54.6 -66.3  275  88 45   1.4   0.8
 34000 -51.9 -61.4  280 100 51   6.8   3.7 | -52.5 -62.5  275  96 50   8.6   4.7
 32000 -47.7 -53.9  280  95 49   6.9   3.8 | -47.2 -53.0  275  94 49   8.8   4.9
 30000 -43.4 -46.1  280  89 46   8.1   4.5 | -41.7 -43.1  280  86 44   6.8   3.8
 29000 -40.3 -40.5  280  81 42   8.2   4.5 | -39.7 -39.5  285  77 40   6.9   3.8
 28000 -37.9 -36.2  280  75 38   8.2   4.5 | -37.6 -35.7  285  68 35   6.9   3.8
 27000 -35.5 -31.9  280  68 35   6.3   3.5 | -35.6 -32.1  290  60 31   6.4   3.5
 26000 -33.6 -28.5  285  60 31   6.5   3.6 | -33.6 -28.5  290  53 27   6.5   3.6
 25000 -31.6 -24.9  290  53 27   6.5   3.6 | -31.7 -25.1  295  45 23   6.5   3.6
 24000 -29.7 -21.5  290  46 24   6.8   3.7 | -29.7 -21.5  295  38 20   7.0   3.8
 23000 -27.6 -17.7  295  42 22   6.9   3.8 | -27.6 -17.7  300  34 18   7.1   3.9
 22000 -25.5 -13.9  300  38 20   6.9   3.8 | -25.5 -13.9  305  31 16   7.1   3.9
 21000 -23.5 -10.3  300  35 18   6.2   3.4 | -23.4 -10.1  305  27 14   6.4   3.5
 20000 -21.6  -6.9  305  31 16   6.3   3.4 | -21.4  -6.5  310  23 12   6.5   3.6
 19500 -20.7  -5.3  310  29 15   6.3   3.4 | -20.4  -4.7  315  22 11   6.5   3.6
 19000 -19.8  -3.6  315  27 14   6.2   3.4 | -19.5  -3.1  320  20 10   6.5   3.6
 18500 -18.8  -1.8  315  26 13   6.9   3.8 | -18.4  -1.1  320  19 10   7.0   3.8
 18000 -17.8  -0.0  320  25 13   6.9   3.8 | -17.4   0.7  325  18  9   7.0   3.8
 17500 -16.7   1.9  325  25 13   6.7   3.7 | -16.4   2.5  325  17  9   7.1   3.9
 17000 -15.8   3.6  325  24 12   6.3   3.5 | -15.3   4.5  330  16  8   7.2   4.0
 16500 -14.9   5.2  325  24 12   6.3   3.5 | -14.2   6.4  340  16  8   7.1   3.9
 16000 -14.1   6.6  325  23 12   4.4   2.4 | -13.4   7.9  340  15  8   4.4   2.4
 15500 -13.4   7.9  325  21 11   4.6   2.5 | -12.7   9.1  340  13  7   4.6   2.5
 15000 -12.4   9.7  320  19 10   5.1   2.8 | -11.6  11.1  335  11  6   5.2   2.9
 14500 -11.7  10.9  320  17  9   5.2   2.8 | -10.8  12.6  330  11  5   5.1   2.8
 14000 -10.9  12.4  320  16  8   5.6   3.1 | -10.2  13.6  325  10  5   3.8   2.1
 13500 -10.1  13.8  320  15  8   5.6   3.1 |  -9.7  14.5  325   9  5   4.1   2.2
 13000  -9.3  15.3  325  15  8   5.8   3.2 |  -9.1  15.6  325   8  4   4.8   2.7
 12500  -8.4  16.9  325  13  7   5.9   3.2 |  -8.5  16.7  330   6  3   4.9   2.7
 12000  -7.7  18.1  325  13  6   5.0   2.8 |  -7.7  18.1  335   5  3   6.0   3.3
 11500  -6.9  19.6  325  12  6   5.2   2.8 |  -6.8  19.8  340   4  2   5.9   3.2
 11000  -6.5  20.3  320  11  6   0.9   0.5 |  -6.1  21.0  340   4  2   4.4   2.4
 10500  -6.3  20.7  310  10  5   0.9   0.5 |  -5.4  22.3  325   5  2   3.7   2.1
 10250  -6.3  20.7  310  10  5  -1.6  -0.9 |  -5.2  22.6  320   5  2   0.8   0.4
 10000  -6.5  20.3  305   9  4  -3.2  -1.7 |  -5.3  22.5  315   5  2  -1.5  -0.8
  9750  -6.8  19.8  305   7  4  -6.0  -3.3 |  -5.5  22.1  300   4  2  -6.0  -3.3
  9500  -7.3  18.9  295   5  2  -2.9  -1.6 |  -6.0  21.2  275   4  2  -4.1  -2.2
  9250  -7.1  19.2  290   3  2   4.2   2.3 |  -6.0  21.2  255   4  2   1.6   0.9
  9000  -6.7  19.9  305   2  1   4.2   2.3 |  -5.9  21.4  240   4  2   1.2   0.6
  8750  -6.3  20.7  015   1  0   9.2   5.0 |  -5.7  21.7  225   4  2   4.4   2.4
  8500  -5.4  22.3  060   2  1  11.1   6.1 |  -5.2  22.6  205   4  2   7.6   4.2
  8250  -4.7  23.5  060   2  1   8.4   4.6 |  -4.6  23.7  195   4  2   7.6   4.2
  8000  -4.0  24.8  055   2  1   8.6   4.7 |  -4.0  24.8  180   3  2   6.9   3.8
  7750  -3.4  25.9  055   3  1  10.3   5.7 |  -3.5  25.7  170   3  2   9.7   5.3
  7500  -2.5  27.5  055   4  2  10.0   5.5 |  -2.6  27.3  150   3  2   9.8   5.4
  7250  -1.9  28.6  055   5  3   7.9   4.3 |  -2.1  28.2  125   3  2   7.3   4.0
  7000  -1.2  29.8  055   7  3   8.2   4.5 |  -1.5  29.3  105   4  2   7.4   4.1
  6750  -0.7  30.7  050   7  4   7.2   3.9 |  -1.0  30.2  100   4  2   9.0   4.9
  6500  -0.2  31.6  050   7  4   6.9   3.8 |  -0.2  31.6  100   4  2  11.0   6.0
  6250   0.3  32.5  045   7  3   7.1   3.9 |   0.6  33.1  100   4  2  10.8   5.9
  6000   0.7  33.3  045   6  3   6.5   3.6 |   1.4  34.5  100   4  2   9.7   5.3
  5750   1.1  34.0  030   4  2   5.0   2.7 |   2.1  35.8  095   4  2  12.2   6.7
  5500   1.4  34.5  010   1  1   4.2   2.3 |   3.3  37.9  095   4  2  20.0  11.0

           01/29/2015 at 1400 MST          |       01/29/2015 at 1700 MST
                                           |
K index... -23.6  LI... +5.2               | K index... -25.7  LI... +5.8
CAPE... 0.0  CIN... M                      | CAPE... 0.0  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 -61.3 -78.3  285  37 19   2.7   1.5 | -61.5 -78.7  290  36 19   2.4   1.3
 45000 -57.4 -71.3  280  49 25   0.9   0.5 | -57.9 -72.2  285  48 25   0.5   0.3
 40000 -56.9 -70.4  275  73 38   0.3   0.1 | -58.1 -72.6  275  92 47  -0.2  -0.1
 38000 -56.0 -68.8  270  81 42   2.3   1.3 | -56.7 -70.1  270  98 50   3.7   2.0
 36000 -54.6 -66.3  270  88 45   2.3   1.3 | -54.5 -66.1  270  98 50   3.7   2.0
 34000 -52.2 -62.0  270  92 47   8.3   4.5 | -51.6 -60.9  270  95 49   7.5   4.1
 32000 -47.1 -52.8  275  87 45   8.4   4.6 | -47.1 -52.8  275  84 43   7.6   4.2
 30000 -42.2 -44.0  280  80 41   7.9   4.3 | -42.4 -44.3  280  76 39   8.1   4.5
 29000 -39.9 -39.8  280  75 38   7.9   4.3 | -40.0 -40.0  285  72 37   8.1   4.5
 28000 -36.9 -34.4  285  68 35   7.9   4.3 | -37.0 -34.6  290  68 35   8.1   4.5
 27000 -34.8 -30.6  285  61 32   5.6   3.0 | -34.7 -30.5  290  63 32   6.3   3.4
 26000 -33.0 -27.4  285  52 27   5.8   3.2 | -32.8 -27.0  290  52 27   6.4   3.5
 25000 -31.3 -24.3  290  43 22   5.8   3.2 | -30.8 -23.4  285  41 21   6.5   3.5
 24000 -29.5 -21.1  290  35 18   6.8   3.7 | -28.9 -20.0  280  32 17   6.1   3.3
 23000 -27.4 -17.3  295  30 16   7.0   3.8 | -27.1 -16.8  280  27 14   6.1   3.3
 22000 -25.3 -13.5  295  26 13   7.0   3.8 | -25.3 -13.5  285  23 12   6.1   3.3
 21000 -23.3  -9.9  300  22 11   6.4   3.5 | -23.4 -10.1  290  19 10   6.9   3.8
 20000 -21.3  -6.3  305  18  9   6.4   3.5 | -21.3  -6.3  290  15  8   6.8   3.8
 19500 -20.4  -4.7  305  16  8   6.4   3.5 | -20.3  -4.5  290  14  7   6.8   3.8
 19000 -19.4  -2.9  310  14  7   6.4   3.5 | -19.2  -2.6  290  12  6   6.9   3.8
 18500 -18.4  -1.1  315  12  6   6.7   3.7 | -18.2  -0.8  290  10  5   6.8   3.7
 18000 -17.4   0.7  320  10  5   6.7   3.7 | -17.2   1.0  285   8  4   6.8   3.7
 17500 -16.4   2.5  335   8  4   7.1   3.9 | -16.2   2.8  280   6  3   6.9   3.8
 17000 -15.3   4.5  340   8  4   7.5   4.1 | -15.2   4.6  280   5  3   6.9   3.8
 16500 -14.2   6.4  345   7  4   7.5   4.1 | -14.1   6.6  285   5  2   7.0   3.8
 16000 -13.1   8.4  350   7  3   7.2   3.9 | -13.0   8.6  280   3  2   7.8   4.3
 15500 -12.0  10.4  360   6  3   7.5   4.1 | -11.8  10.8  270   2  1   7.9   4.4
 15000 -11.1  12.0  005   5  3   3.8   2.1 | -10.8  12.6  250   1  1   6.0   3.3
 14500 -10.5  13.1  355   5  2   3.9   2.1 |  -9.9  14.2  250   1  1   6.1   3.3
 14000  -9.7  14.5  325   4  2   3.5   1.9 |  -8.7  16.3  260   2  1   4.6   2.5
 13500  -9.3  15.3  300   4  2   3.9   2.1 |  -8.0  17.6  265   3  1   4.9   2.7
 13000  -8.8  16.2  280   5  2   3.8   2.1 |  -7.5  18.5  255   4  2   2.9   1.6
 12500  -8.3  17.1  265   5  2   4.1   2.2 |  -7.1  19.2  245   5  2   3.5   1.9
 12000  -7.7  18.1  250   4  2   5.0   2.8 |  -6.7  19.9  235   6  3   2.6   1.4
 11500  -7.0  19.4  240   4  2   5.0   2.7 |  -6.4  20.5  225   6  3   2.8   1.5
 11000  -6.3  20.7  245   3  2   4.6   2.5 |  -5.9  21.4  215   6  3   3.9   2.1
 10500  -5.6  21.9  255   3  2   4.4   2.4 |  -5.4  22.3  210   6  3   3.7   2.1
 10250  -5.3  22.5  260   3  2   3.4   1.9 |  -5.1  22.8  205   6  3   3.4   1.9
 10000  -5.1  22.8  255   3  2   2.6   1.4 |  -4.9  23.2  205   5  3   3.1   1.7
  9750  -4.9  23.2  245   3  2   2.0   1.1 |  -4.6  23.7  205   5  3   3.1   1.7
  9500  -4.8  23.4  230   4  2   1.8   1.0 |  -4.4  24.1  200   6  3   2.8   1.6
  9250  -4.6  23.7  215   4  2   1.9   1.0 |  -4.3  24.3  190   6  3   2.3   1.3
  9000  -4.5  23.9  195   4  2   2.0   1.1 |  -4.1  24.6  180   7  4   2.6   1.4
  8750  -4.3  24.3  175   5  3   2.7   1.5 |  -3.8  25.2  170   8  4   4.9   2.7
  8500  -4.0  24.8  155   6  3   6.1   3.4 |  -3.4  25.9  160   9  5   8.2   4.5
  8250  -3.4  25.9  150   6  3   8.3   4.5 |  -2.7  27.1  160   9  5   9.4   5.1
  8000  -2.9  26.8  150   6  3   7.5   4.1 |  -2.0  28.4  160   9  5   9.1   5.0
  7750  -2.2  28.0  145   6  3  10.2   5.6 |  -1.3  29.7  155   9  5  11.1   6.1
  7500  -1.4  29.5  145   6  3  10.9   6.0 |  -0.4  31.3  155   9  4  10.6   5.8
  7250  -0.7  30.7  145   6  3   9.8   5.4 |   0.3  32.5  150   8  4   9.1   5.0
  7000   0.1  32.2  145   6  3   9.1   5.0 |   1.0  33.8  150   8  4   9.4   5.1
  6750   0.7  33.3  145   6  3   9.3   5.1 |   1.7  35.1  145   8  4   9.5   5.2
  6500   1.5  34.7  145   5  3  10.7   5.9 |   2.4  36.3  145   7  4   9.7   5.3
  6250   2.3  36.1  145   5  3  10.4   5.7 |   3.1  37.6  140   7  4   9.9   5.4
  6000   3.1  37.6  145   5  3  10.5   5.8 |   3.9  39.0  135   7  4   9.1   5.0
  5750   3.9  39.0  145   5  3  13.7   7.5 |   4.5  40.1  135   6  3   7.4   4.0
  5500   5.1  41.2  145   5  3  18.9  10.4 |   5.0  41.0  130   5  2   7.2   3.9
________________________________________________________________________________

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

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

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

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

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

DEFINITIONS:

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

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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