Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 100058
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1758 MST Monday, January 9, 2017

This forecast is for Tuesday, January 10, 2017:

If the trigger temperature of 41.3 F/5.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 639 ft/min (3.2 m/s)
   Maximum height of thermals.................. 15063 ft MSL (9684 ft AGL)

Forecast maximum temperature................... 49.0 F/9.9 C
Time of trigger temperature.................... 1030 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11022 ft MSL (5643 ft AGL)
Thermal soaring outlook for Wednesday 01/11.... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Improving after 1100 MST
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 34141 ft MSL (28762 ft AGL)
Wave soaring outlook for Wednesday 01/11....... Excellent

Remarks... Strong westerly flow aloft across the state with an amplified
           mountainwave developing in the afternoon.

Sunrise/Sunset.................... 07:20:11 / 16:54:13 MST
Total possible sunshine........... 9 hr 34 min 2 sec (574 min 2 sec)
Altitude of sun at 12:07:12 MST... 28.37 degrees

Upper air data from numerical model forecast valid on 01/10/2017 at 0500 MST

Freezing level.................. 7038 ft MSL (1659 ft AGL)
Convective condensation level... 13631 ft MSL (8252 ft AGL)
Lifted condensation level....... 13996 ft MSL (8617 ft AGL)
Lifted index.................... +3.9
K index......................... +5.1

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  -62.5 -80.5   265   40   21   2.0   1.1      M     M       M      M    M
 45000  -59.4 -74.9   270   36   19   2.0   1.1      M     M       M      M    M
 40000  -57.4 -71.3   285   48   25   1.2   0.7      M     M       M      M    M
 38000  -56.6 -69.9   285   54   28   1.9   1.1      M     M       M      M    M
 36000  -55.3 -67.5   290   56   29   2.1   1.2      M     M       M      M    M
 34000  -53.9 -65.0   290   58   30   2.0   1.1      M     M       M      M    M
 32000  -50.9 -59.6   290   58   30   5.5   3.0      M     M       M      M    M
 30000  -47.6 -53.7   290   58   30   5.4   3.0      M     M       M      M    M
 29000  -45.8 -50.4   290   57   29   6.6   3.6   28.0  82.4    14.0      M    M
 28000  -43.8 -46.8   290   56   29   6.6   3.6   26.7  80.0    13.2      M    M
 27000  -41.8 -43.2   290   55   28   6.6   3.6   25.5  77.9    12.4      M    M
 26000  -40.0 -40.0   290   54   28   4.1   2.3   24.2  75.6    11.6      M    M
 25000  -38.8 -37.8   290   50   26   4.1   2.2   21.9  71.5     9.9      M    M
 24000  -37.6 -35.7   290   47   24   4.1   2.2   19.8  67.7     8.3      M    M
 23000  -36.3 -33.3   285   44   23   5.9   3.2   17.9  64.3     6.9      M    M
 22000  -34.4 -29.9   285   42   22   6.3   3.4   16.6  61.8     5.8      M    M
 21000  -32.5 -26.5   285   40   21   6.3   3.4   15.3  59.6     4.9      M    M
 20000  -30.1 -22.2   280   38   20   6.6   3.6   13.8  56.9     3.7      M    M
 19500  -29.2 -20.6   280   37   19   6.6   3.6   13.3  55.9     3.2      M    M
 19000  -28.2 -18.8   280   36   19   6.6   3.6   12.7  54.9     2.7      M    M
 18500  -27.2 -17.0   280   36   18   6.6   3.6   12.2  54.0     2.3      M    M
 18000  -26.2 -15.2   280   35   18   6.2   3.4   11.7  53.0     1.9      M    M
 17500  -25.3 -13.5   280   33   17   6.2   3.4   11.0  51.9     1.3      M    M
 17000  -24.4 -11.9   285   32   16   6.8   3.7   10.4  50.8     0.8      M    M
 16500  -23.2  -9.8   285   30   16   8.1   4.5   10.1  50.2     0.5      M    M
 16000  -22.0  -7.6   285   29   15   8.1   4.5    9.8  49.7     0.2      M    M
 15500  -20.7  -5.3   285   28   15   9.3   5.1    9.7  49.4     0.1      M    M
 15000  -19.4  -2.9   285   28   14   9.3   5.1    9.6  49.2    -0.0    828  4.2
 14500  -18.1  -0.6   285   28   14   8.0   4.4    9.4  48.9    -0.2    774  3.9
 14000  -16.9   1.6   285   28   14   8.1   4.4    9.1  48.4    -0.4    724  3.7
 13500  -15.7   3.7   285   28   14   7.3   4.0    8.8  47.8    -0.7    674  3.4
 13000  -14.6   5.7   285   28   14   7.2   3.9    8.4  47.0    -1.2    627  3.2
 12500  -13.6   7.5   290   28   14   6.7   3.7    7.9  46.3    -1.6    581  3.0
 12000  -12.6   9.3   290   27   14   6.6   3.6    7.4  45.3    -2.1    537  2.7
 11500  -11.6  11.1   290   26   14   6.9   3.8    6.9  44.4    -2.5    493  2.5
 11000  -10.6  12.9   290   25   13   6.9   3.8    6.5  43.6    -3.0    447  2.3
 10500   -9.5  14.9   290   24   12   7.5   4.1    6.1  42.9    -3.4    400  2.0
 10250   -9.0  15.8   290   23   12   7.7   4.2    5.9  42.6    -3.6    376  1.9
 10000   -8.4  16.9   290   22   11   7.5   4.1    5.7  42.3    -3.8    352  1.8
  9750   -7.9  17.8   290   21   11   8.1   4.5    5.6  42.0    -3.9    328  1.7
  9500   -7.2  19.0   290   20   10   9.0   4.9    5.5  41.9    -4.0    301  1.5
  9250   -6.5  20.3   290   19   10   9.1   5.0    5.4  41.8    -4.1    274  1.4
  9000   -5.9  21.4   290   18    9   8.6   4.7    5.4  41.7    -4.2    247  1.3
  8750   -5.3  22.5   290   18    9   8.9   4.9    5.3  41.5    -4.3    220  1.1
  8500   -4.5  23.9   290   17    9   9.9   5.4    5.3  41.5    -4.3    192  1.0
  8250   -3.8  25.2   290   17    9   9.0   4.9    5.2  41.4    -4.4    163  0.8
  8000   -3.1  26.4   290   16    8  11.7   6.4    5.2  41.4    -4.4    134  0.7
  7750   -2.2  28.0   290   16    8  10.9   6.0    5.5  41.8    -4.2     99  0.5
  7500   -1.5  29.3   290   15    8   8.0   4.4    5.4  41.6    -4.3     72  0.4
  7250   -0.9  30.4   290   15    8   8.1   4.4    5.3  41.5    -4.4     46  0.2
  7000   -0.2  31.6   290   14    7  11.8   6.5    5.2  41.4    -4.5     19  0.1
  6750    0.7  33.3   295   14    7  11.0   6.0    5.5  41.8    -4.3      M    M
  6500    1.3  34.3   295   13    7   7.1   3.9    5.3  41.5    -4.4      M    M
  6250    1.9  35.4   295   13    7   7.4   4.0    5.2  41.3    -4.6      M    M
  6000    2.4  36.3   295   12    6   5.8   3.2    4.9  40.8    -4.9      M    M
  5750    2.8  37.0   295   10    5   5.3   2.9    4.6  40.3    -5.2      M    M
  5500    0.4  32.7   290    4    2 -65.0 -35.7    0.8  33.5    -9.0      M    M

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

           01/10/2017 at 0800 MST          |       01/10/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +4.4        | CAPE...     0.0    LI...       +5.1
CINH...    -0.2    K Index...  -1.9        | CINH...     0.0    K Index...  +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 -62.8 -81.0  270  45 23   1.5   0.8 | -65.5 -85.9  275  47 24   2.7   1.5
 45000 -60.5 -76.9  280  48 25   1.5   0.8 | -61.5 -78.7  280  50 26   2.7   1.5
 40000 -58.7 -73.7  285  57 29   1.1   0.6 | -59.7 -75.5  285  58 30   0.9   0.5
 38000 -58.0 -72.4  290  60 31   2.9   1.6 | -58.9 -74.0  285  62 32   4.0   2.2
 36000 -56.1 -69.0  290  61 32   3.1   1.7 | -56.4 -69.5  290  63 32   3.7   2.0
 34000 -54.0 -65.2  290  63 32   2.9   1.6 | -54.2 -65.6  290  63 33   3.9   2.1
 32000 -50.7 -59.3  290  62 32   6.0   3.3 | -50.4 -58.7  295  63 32   6.6   3.6
 30000 -47.1 -52.8  290  62 32   5.9   3.2 | -46.4 -51.5  295  62 32   6.8   3.7
 29000 -45.1 -49.2  295  60 31   6.8   3.7 | -44.2 -47.6  295  60 31   7.3   4.0
 28000 -43.0 -45.4  295  59 30   6.8   3.7 | -42.0 -43.6  295  59 30   7.3   4.0
 27000 -41.0 -41.8  295  58 30   6.8   3.7 | -39.8 -39.6  295  57 29   7.3   4.0
 26000 -39.1 -38.4  295  56 29   5.2   2.8 | -37.6 -35.7  295  56 29   7.3   4.0
 25000 -37.5 -35.5  295  53 27   5.4   2.9 | -35.4 -31.7  295  55 28   7.3   4.0
 24000 -35.9 -32.6  295  50 26   5.4   2.9 | -33.2 -27.8  295  54 28   7.3   4.0
 23000 -34.3 -29.7  295  48 24   5.2   2.8 | -31.2 -24.2  295  53 27   5.2   2.9
 22000 -32.7 -26.9  290  45 23   5.2   2.8 | -29.6 -21.3  295  49 25   5.4   3.0
 21000 -31.2 -24.2  290  43 22   5.2   2.9 | -28.0 -18.4  295  46 24   5.4   3.0
 20000 -29.4 -20.9  285  41 21   6.8   3.7 | -26.3 -15.3  295  43 22   5.5   3.0
 19500 -27.9 -18.2  285  40 21   6.8   3.7 | -25.1 -13.2  290  40 21   5.5   3.0
 19000 -26.9 -16.4  285  39 20   6.8   3.7 | -24.3 -11.7  290  38 20   5.5   3.0
 18500 -25.9 -14.6  285  38 20   6.8   3.7 | -23.5 -10.3  290  37 19   5.4   3.0
 18000 -24.9 -12.8  285  38 19   6.5   3.6 | -22.6  -8.7  285  36 18   6.6   3.6
 17500 -23.9 -11.0  285  37 19   6.5   3.6 | -21.6  -6.9  285  35 18   6.5   3.6
 17000 -23.0  -9.4  285  36 18   6.6   3.6 | -20.7  -5.3  285  35 18   6.3   3.5
 16500 -21.9  -7.4  290  34 18   6.8   3.7 | -19.7  -3.5  285  35 18   6.2   3.4
 16000 -20.9  -5.6  290  33 17   6.8   3.8 | -18.8  -1.8  285  34 18   6.2   3.4
 15500 -19.9  -3.8  290  32 17   7.1   3.9 | -17.9  -0.2  285  34 17   6.2   3.4
 15000 -18.8  -1.8  290  31 16   7.1   3.9 | -17.0   1.4  285  33 17   6.2   3.4
 14500 -17.7   0.1  290  30 16   7.6   4.2 | -16.0   3.2  285  32 17   6.8   3.7
 14000 -16.6   2.1  290  29 15   7.5   4.1 | -15.0   5.0  280  31 16   6.7   3.7
 13500 -15.4   4.3  290  28 14   7.7   4.2 | -14.0   6.8  280  31 16   7.0   3.8
 13000 -14.3   6.3  290  27 14   7.7   4.2 | -12.9   8.8  280  30 15   7.0   3.8
 12500 -13.2   8.2  285  25 13   7.3   4.0 | -11.9  10.6  280  29 15   7.3   4.0
 12000 -12.1  10.2  285  25 13   7.3   4.0 | -10.8  12.6  280  29 15   7.3   4.0
 11500 -11.0  12.2  285  25 13   7.5   4.1 |  -9.7  14.5  275  28 14   7.1   3.9
 11000  -9.9  14.2  285  25 13   7.6   4.2 |  -8.7  16.3  275  27 14   7.1   3.9
 10500  -8.8  16.2  280  24 13   7.1   3.9 |  -7.6  18.3  275  27 14   7.2   3.9
 10250  -8.3  17.1  280  24 12   6.8   3.7 |  -7.1  19.2  275  26 13   6.7   3.7
 10000  -7.8  18.0  280  24 12   7.6   4.2 |  -6.6  20.1  275  26 13   8.4   4.6
  9750  -7.2  19.0  280  23 12   7.8   4.3 |  -5.9  21.4  270  25 13   9.1   5.0
  9500  -6.7  19.9  280  23 12   7.0   3.8 |  -5.3  22.5  270  24 12   8.5   4.4
  9250  -6.1  21.0  280  22 11   7.2   4.0 |  -4.7  23.5  270  23 12   8.4   4.6
  9000  -5.6  21.9  275  21 11   6.7   3.7 |  -4.0  24.8  270  22 12   7.7   4.2
  8750  -5.1  22.8  275  20 10   6.8   3.7 |  -3.5  25.7  270  22 11   7.6   4.2
  8500  -4.6  23.7  275  19 10   7.4   4.0 |  -2.9  26.8  270  21 11   8.3   4.5
  8250  -4.1  24.6  275  18  9   7.2   4.0 |  -2.3  27.9  265  20 10   8.2   4.5
  8000  -3.5  25.7  270  17  9   7.1   3.9 |  -1.7  28.9  265  19 10   7.8   4.3
  7750  -3.0  26.6  270  16  8   7.7   4.2 |  -1.1  30.0  265  18  9   8.0   4.4
  7500  -2.4  27.7  270  15  8   8.2   4.5 |  -0.5  31.1  265  17  9   8.8   4.8
  7250  -1.8  28.8  265  14  7   8.1   4.4 |   0.2  32.4  265  16  8   8.6   4.7
  7000  -1.2  29.8  265  13  7   8.1   4.4 |   0.8  33.4  265  15  8   7.3   4.0
  6750  -0.6  30.9  260  12  6   7.4   4.1 |   1.3  34.3  265  14  7   7.8   4.3
  6500  -0.1  31.8  260  11  6   7.7   4.2 |   2.0  35.6  260  13  7   9.5   5.2
  6250   0.5  32.9  255  10  5   5.4   3.0 |   2.6  36.7  260  12  6   7.8   4.3
  6000   0.7  33.3  250   8  4   2.6   1.4 |   3.1  37.6  260  10  5   6.7   3.7
  5750   0.9  33.6  245   7  4   2.1   1.2 |   3.6  38.5  260   9  5   6.0   3.3
  5500   0.7  33.3  240   6  3  -8.1  -4.4 |   4.0  39.2  255   7  4   4.4   2.4

           01/10/2017 at 1400 MST          |       01/10/2017 at 1700 MST
                                           |
CAPE...     0.0    LI...       +7.1        | CAPE...     0.0    LI...       +8.0
CINH...    -0.1    K Index...  -2.1        | CINH...     0.0    K Index...  -7.3
                                           |
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 -67.0 -88.6  275  47 24   3.6   2.0 | -68.9 -92.0  275  50 26   3.1   1.7
 45000 -61.6 -78.9  280  51 26   3.7   2.0 | -64.3 -83.7  280  55 28   3.1   1.7
 40000 -60.7 -77.3  280  59 30   0.0   0.0 | -62.3 -80.1  280  55 28   1.0   0.5
 38000 -60.2 -76.4  280  61 32   3.5   1.9 | -61.1 -78.0  280  55 28   4.4   2.4
 36000 -58.0 -72.4  285  62 32   3.6   2.0 | -58.4 -73.1  285  54 28   4.4   2.4
 34000 -55.9 -68.6  285  63 32   4.1   2.2 | -55.8 -68.4  285  53 27   6.1   3.3
 32000 -51.2 -60.2  290  62 32   8.1   4.4 | -51.1 -60.0  285  51 26   8.0   4.4
 30000 -46.4 -51.5  290  61 31   8.3   4.5 | -46.3 -51.3  280  50 25   8.6   4.7
 29000 -43.3 -45.9  290  59 30   8.2   4.5 | -43.0 -45.4  285  48 24   8.7   4.8
 28000 -40.9 -41.6  290  57 29   8.2   4.5 | -40.4 -40.7  285  46 24   8.7   4.8
 27000 -38.4 -37.1  290  55 28   8.3   4.5 | -37.8 -36.0  285  45 23   8.7   4.8
 26000 -36.2 -33.2  295  53 27   7.1   3.9 | -35.4 -31.7  285  43 22   8.1   4.4
 25000 -34.0 -29.2  295  51 26   7.1   3.9 | -33.0 -27.4  290  41 21   8.1   4.4
 24000 -31.9 -25.4  295  49 25   7.2   3.9 | -30.5 -22.9  290  39 20   8.1   4.5
 23000 -29.7 -21.5  295  47 24   7.8   4.3 | -28.1 -18.6  290  37 19   8.0   4.4
 22000 -27.3 -17.1  290  45 23   7.8   4.3 | -25.7 -14.3  290  35 18   8.0   4.4
 21000 -25.0 -13.0  290  43 22   7.9   4.3 | -23.3  -9.9  290  32 17   8.1   4.4
 20000 -22.8  -9.0  290  42 21   7.1   3.9 | -20.8  -5.4  285  30 16   8.4   4.6
 19500 -21.8  -7.2  290  41 21   7.1   3.9 | -19.6  -3.3  285  29 15   8.4   4.6
 19000 -20.7  -5.3  295  40 21   7.1   3.9 | -18.3  -0.9  285  28 15   8.4   4.6
 18500 -19.6  -3.3  295  39 20   7.2   3.9 | -17.1   1.2  285  27 14   8.6   4.7
 18000 -18.6  -1.5  295  39 20   5.7   3.1 | -15.9   3.4  285  27 14   7.0   3.9
 17500 -17.9  -0.2  295  37 19   5.3   2.9 | -14.8   5.4  285  27 14   7.1   3.9
 17000 -17.1   1.2  295  36 19   5.1   2.8 | -13.8   7.2  285  27 14   6.6   3.6
 16500 -16.4   2.5  290  34 18   4.5   2.5 | -12.9   8.8  285  27 14   6.0   3.3
 16000 -15.7   3.7  290  33 17   4.6   2.5 | -12.0  10.4  285  26 13   6.0   3.3
 15500 -14.7   5.5  285  31 16   4.3   2.4 | -11.1  12.0  280  25 13   5.5   3.0
 15000 -14.1   6.6  285  31 16   4.5   2.5 |  -9.9  14.2  280  25 13   5.7   3.1
 14500 -13.3   8.1  280  30 16   5.8   3.2 |  -9.0  15.8  280  24 12   6.0   3.3
 14000 -12.5   9.5  280  30 15   5.7   3.1 |  -8.1  17.4  275  24 12   6.0   3.3
 13500 -11.6  11.1  275  30 15   6.2   3.4 |  -7.3  18.9  275  24 12   5.7   3.1
 13000 -10.7  12.7  275  30 15   6.1   3.3 |  -6.4  20.5  275  24 12   5.8   3.2
 12500  -9.8  14.4  275  30 15   6.6   3.6 |  -5.6  21.9  270  24 12   5.1   2.8
 12000  -8.8  16.2  275  29 15   6.5   3.6 |  -4.8  23.4  270  24 12   5.3   2.9
 11500  -7.8  18.0  270  29 15   7.0   3.8 |  -4.2  24.4  270  24 12   4.0   2.2
 11000  -6.8  19.8  270  28 14   7.0   3.8 |  -3.6  25.5  270  24 13   4.2   2.3
 10500  -5.8  21.6  270  27 14   6.6   3.6 |  -3.0  26.6  270  25 13   3.5   1.9
 10250  -5.3  22.5  265  26 13   6.3   3.5 |  -2.7  27.1  270  25 13   3.5   1.9
 10000  -4.8  23.4  265  25 13   8.9   4.9 |  -2.5  27.5  270  25 13   4.3   2.3
  9750  -4.0  24.8  265  25 13   9.6   5.3 |  -2.1  28.2  270  25 13   4.9   2.7
  9500  -3.4  25.9  265  24 12   8.1   4.4 |  -1.8  28.8  265  24 13   4.9   2.7
  9250  -2.8  27.0  265  23 12   8.1   4.4 |  -1.4  29.5  265  24 12   4.5   2.5
  9000  -2.2  28.0  265  22 12   9.7   5.3 |  -1.1  30.0  265  24 12   6.0   3.3
  8750  -1.4  29.5  265  22 11  10.1   5.5 |  -0.5  31.1  265  23 12   7.4   4.1
  8500  -0.7  30.7  265  21 11   8.7   4.8 |  -0.0  32.0  265  22 11   7.0   3.9
  8250  -0.1  31.8  265  20 11   8.8   4.8 |   0.5  32.9  260  21 11   7.0   3.8
  8000   0.6  33.1  265  20 10   9.7   5.3 |   1.0  33.8  260  20 10   7.7   4.2
  7750   1.3  34.3  260  19 10   9.5   5.2 |   1.6  34.9  260  19 10   8.4   4.6
  7500   2.0  35.6  260  18  9   8.4   4.6 |   2.2  36.0  260  17  9   8.1   4.5
  7250   2.6  36.7  260  17  9   8.7   4.7 |   2.8  37.0  260  16  8   8.1   4.5
  7000   3.2  37.8  260  16  8   9.2   5.1 |   3.4  38.1  255  15  8   8.7   4.8
  6750   3.9  39.0  260  15  8   8.8   4.8 |   4.1  39.4  255  14  7   8.2   4.5
  6500   4.5  40.1  260  14  7   8.0   4.4 |   4.6  40.3  255  12  6   7.7   4.2
  6250   5.1  41.2  260  13  7   7.8   4.3 |   5.2  41.4  250  11  6   6.6   3.6
  6000   5.7  42.3  260  11  6   7.2   4.0 |   5.6  42.1  250   9  5   4.1   2.3
  5750   6.2  43.2  260  10  5   7.2   4.0 |   5.9  42.6  245   8  4   4.6   2.5
  5500   6.7  44.1  260   8  4   6.1   3.4 |   6.0  42.8  240   6  3  -2.8  -1.6
________________________________________________________________________________

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.

CINH (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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