Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 050023
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1723 MST Sunday, December 4, 2016

This forecast is for Monday, December 5, 2016:

If the trigger temperature of 50.7 F/10.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 51 ft/min (0.3 m/s)
   Maximum height of thermals.................. 8970 ft MSL (3663 ft AGL)

Forecast maximum temperature................... 50.0 F/10.5 C
Time of trigger temperature.................... 1415 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 5946 ft MSL (639 ft AGL)
Thermal soaring outlook for Tuesday 12/06...... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 14410 ft MSL (9103 ft AGL)
Wave soaring outlook for Tuesday 12/06......... Poor

Remarks... None

Sunrise/Sunset.................... 07:05:49 / 16:34:59 MST
Total possible sunshine........... 9 hr 29 min 10 sec (569 min 10 sec)
Altitude of sun at 11:50:29 MST... 27.81 degrees

Upper air data from numerical model forecast valid on 12/05/2016 at 0500 MST

Freezing level.................. 5334 ft MSL (27 ft AGL)
Additional freezing level....... 8510 ft MSL (3203 ft AGL)
Convective condensation level... 19242 ft MSL (13935 ft AGL)
Lifted condensation level....... 14089 ft MSL (8782 ft AGL)
Lifted index.................... +9.4
K index......................... +0.7

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  -61.3 -78.3   260   58   30   1.7   0.9      M     M       M      M    M
 45000  -58.7 -73.7   255   71   37   1.7   0.9      M     M       M      M    M
 40000  -58.1 -72.6   280   66   34   0.2   0.1      M     M       M      M    M
 38000  -57.9 -72.2   285   66   34   1.0   0.5      M     M       M      M    M
 36000  -57.3 -71.1   270   64   33   1.0   0.5      M     M       M      M    M
 34000  -56.7 -70.1   260   65   34   3.0   1.7      M     M       M      M    M
 32000  -50.6 -59.1   260   65   34   9.3   5.1      M     M       M      M    M
 30000  -45.1 -49.2   260   65   34   9.0   5.0   30.5  86.9    15.4      M    M
 29000  -42.4 -44.3   260   64   33   8.9   4.9   30.0  86.1    15.2      M    M
 28000  -39.7 -39.5   260   62   32   8.9   4.9   29.7  85.5    15.2      M    M
 27000  -37.0 -34.6   260   61   31   9.1   5.0   29.5  85.1    15.2      M    M
 26000  -34.8 -30.6   260   59   30   6.9   3.8   28.6  83.5    14.7      M    M
 25000  -32.7 -26.9   260   56   29   7.0   3.8   27.5  81.5    14.0      M    M
 24000  -30.7 -23.3   260   54   28   7.0   3.8   26.6  79.8    13.3      M    M
 23000  -28.3 -18.9   255   52   27   8.7   4.8   25.9  78.6    13.0      M    M
 22000  -25.7 -14.3   255   50   26   8.8   4.8   25.5  77.9    12.8      M    M
 21000  -23.0  -9.4   250   48   25   8.9   4.9   25.2  77.4    12.7      M    M
 20000  -20.5  -4.9   250   46   24   8.2   4.5   24.7  76.4    12.4      M    M
 19500  -19.3  -2.7   255   45   23   8.2   4.5   24.4  75.9    12.2      M    M
 19000  -18.1  -0.6   255   44   23   8.2   4.5   24.1  75.4    12.0      M    M
 18500  -16.9   1.6   255   43   22   8.3   4.5   23.9  75.0    11.9      M    M
 18000  -15.7   3.7   255   43   22   7.1   3.9   23.6  74.5    11.7      M    M
 17500  -14.7   5.5   260   43   22   6.9   3.8   23.1  73.6    11.3      M    M
 17000  -13.7   7.3   265   42   22   6.7   3.7   22.6  72.7    10.9      M    M
 16500  -12.3   9.9   270   45   23   6.2   3.4   21.7  71.1    10.2      M    M
 16000  -11.3  11.7   275   47   24   6.0   3.3   21.1  70.1     9.7      M    M
 15500  -10.5  13.1   275   48   25   5.7   3.1   20.5  68.8     9.2      M    M
 15000   -9.6  14.7   275   50   26   5.7   3.1   19.8  67.6     8.6      M    M
 14500   -8.9  16.0   280   52   27   4.8   2.6   19.0  66.2     8.0      M    M
 14000   -8.2  17.2   280   53   27   4.9   2.7   18.2  64.8     7.3      M    M
 13500   -7.5  18.5   280   54   28   4.4   2.4   17.4  63.3     6.5      M    M
 13000   -6.8  19.8   280   55   28   4.4   2.4   16.5  61.7     5.8      M    M
 12500   -6.1  21.0   280   54   28   4.5   2.5   15.7  60.2     5.0      M    M
 12000   -5.5  22.1   280   53   27   4.5   2.5   14.8  58.7     4.2      M    M
 11500   -4.8  23.4   280   50   26   4.6   2.5   14.0  57.2     3.5      M    M
 11000   -4.1  24.6   280   47   24   4.7   2.6   13.2  55.7     2.7      M    M
 10500   -3.4  25.9   280   42   22   4.3   2.3   12.3  54.2     1.9      M    M
 10250   -3.1  26.4   280   39   20   4.2   2.3   11.9  53.4     1.5      M    M
 10000   -2.8  27.0   280   37   19   5.5   3.0   11.5  52.7     1.1      M    M
  9750   -2.3  27.9   280   34   17   6.4   3.5   11.2  52.2     0.9      M    M
  9500   -1.9  28.6   275   30   16   6.0   3.3   10.9  51.7     0.6      M    M
  9250   -1.4  29.5   275   27   14   6.2   3.4   10.6  51.2     0.3      M    M
  9000   -1.0  30.2   275   23   12   5.7   3.1   10.4  50.7     0.0      M    M
  8750   -0.5  31.1   275   20   10   6.5   3.6   10.1  50.1    -0.3    233  1.2
  8500    0.0  32.0   270   17    9   7.7   4.2    9.9  49.7    -0.5    209  1.1
  8250    0.6  33.1   270   15    8   6.9   3.8    9.7  49.4    -0.6    185  0.9
  8000    1.1  34.0   265   13    6   8.7   4.8    9.5  49.1    -0.8    161  0.8
  7750    1.8  35.2   255   11    6   8.9   4.9    9.5  49.1    -0.8    132  0.7
  7500    2.4  36.3   250   10    5   7.5   4.1    9.3  48.8    -1.0    107  0.5
  7250    3.0  37.4   245    9    5   7.7   4.2    9.2  48.5    -1.1     83  0.4
  7000    3.6  38.5   235    8    4   8.1   4.5    9.0  48.2    -1.3     58  0.3
  6750    4.2  39.6   225    8    4   8.8   4.8    8.9  48.1    -1.4     31  0.2
  6500    4.9  40.8   220    8    4  10.0   5.5    8.9  48.0    -1.4      3  0.0
  6250    5.6  42.1   215    8    4   6.2   3.4    8.8  47.9    -1.5      M    M
  6000    5.5  41.9   210    9    5  -8.7  -4.8    8.1  46.5    -2.3      M    M
  5750    4.4  39.9   200   11    5 -17.2  -9.4    6.2  43.2    -4.1      M    M
  5500    3.0  37.4   195   10    5 -20.9 -11.4    4.1  39.4    -6.2     29  0.1

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

           12/05/2016 at 0800 MST          |       12/05/2016 at 1100 MST
                                           |
K index... -14.7  LI... +6.6               | K index... -23.2  LI... +5.2
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 -60.6 -77.1  255  66 34   1.0   0.5 | -58.7 -73.7  255  55 29   0.7   0.4
 45000 -59.1 -74.4  250  78 40   1.0   0.5 | -57.7 -71.9  250  80 41   0.7   0.4
 40000 -58.2 -72.8  270  64 33   0.5   0.3 | -58.2 -72.8  260  60 31  -0.5  -0.3
 38000 -57.7 -71.9  275  60 31   2.0   1.1 | -58.0 -72.4  265  54 28   2.9   1.6
 36000 -56.4 -69.5  260  61 31   2.1   1.1 | -56.2 -69.2  255  62 32   3.0   1.6
 34000 -55.2 -67.4  245  66 34   2.5   1.3 | -54.4 -65.9  250  70 36   2.7   1.5
 32000 -51.2 -60.2  250  66 34   7.0   3.9 | -51.4 -60.5  250  74 38   5.4   3.0
 30000 -47.0 -52.6  255  68 35   7.4   4.1 | -48.2 -54.8  255  77 40   5.3   2.9
 29000 -43.9 -47.0  260  68 35   8.3   4.6 | -45.4 -49.7  260  77 40   7.9   4.3
 28000 -41.4 -42.5  260  68 35   8.3   4.6 | -43.1 -45.6  260  77 39   7.9   4.3
 27000 -38.9 -38.0  265  68 35   8.3   4.6 | -40.7 -41.3  265  76 39   7.9   4.3
 26000 -36.3 -33.3  265  67 35   8.8   4.8 | -38.2 -36.8  265  75 38   8.6   4.7
 25000 -33.7 -28.7  265  66 34   8.8   4.8 | -35.6 -32.1  270  72 37   8.7   4.7
 24000 -31.1 -24.0  265  65 34   8.8   4.8 | -33.1 -27.6  270  70 36   8.6   4.7
 23000 -28.6 -19.5  265  63 32   7.7   4.2 | -30.7 -23.3  270  66 34   7.0   3.8
 22000 -26.3 -15.3  265  59 30   7.7   4.2 | -28.6 -19.5  270  60 31   7.0   3.8
 21000 -24.0 -11.2  265  54 28   7.7   4.2 | -26.5 -15.7  270  54 28   7.0   3.8
 20000 -21.8  -7.2  265  49 25   7.2   3.9 | -24.4 -11.9  270  51 26   7.1   3.9
 19500 -20.7  -5.3  265  47 24   7.2   3.9 | -23.4 -10.1  270  50 26   7.1   3.9
 19000 -19.7  -3.5  260  44 23   7.2   3.9 | -22.3  -8.1  265  50 26   7.1   3.9
 18500 -18.6  -1.5  260  41 21   7.2   3.9 | -21.2  -6.2  265  49 25   7.0   3.9
 18000 -17.5   0.5  260  39 20   7.8   4.3 | -20.1  -4.2  265  48 25   8.6   4.7
 17500 -16.3   2.7  260  37 19   7.9   4.4 | -18.7  -1.7  260  46 24   9.2   5.1
 17000 -15.1   4.8  255  35 18   7.9   4.4 | -17.4   0.7  260  45 23   9.2   5.0
 16500 -13.9   7.0  260  35 18   7.9   4.3 | -16.0   3.2  260  44 23   8.9   4.9
 16000 -12.7   9.1  260  35 18   8.0   4.4 | -14.7   5.5  260  44 23   8.9   4.9
 15500 -11.2  11.8  270  37 19   6.1   3.4 | -13.4   7.9  260  44 23   8.7   4.8
 15000 -10.3  13.5  270  39 20   6.1   3.4 | -11.4  11.5  260  43 22   8.6   4.7
 14500  -9.3  15.3  275  42 21   6.5   3.6 | -10.3  13.5  260  43 22   7.1   3.9
 14000  -8.4  16.9  275  44 23   6.7   3.7 |  -9.2  15.4  265  43 22   7.4   4.1
 13500  -7.6  18.3  280  46 24   4.5   2.5 |  -8.2  17.2  265  44 22   5.8   3.2
 13000  -6.9  19.6  280  48 25   4.6   2.5 |  -7.3  18.9  265  44 23   6.0   3.3
 12500  -6.2  20.8  280  50 26   5.3   2.9 |  -6.6  20.1  270  45 23   3.8   2.1
 12000  -5.4  22.3  280  51 26   5.5   3.0 |  -6.1  21.0  270  45 23   3.8   2.1
 11500  -4.7  23.5  285  51 27   4.2   2.3 |  -5.6  21.9  270  45 23   2.4   1.3
 11000  -4.1  24.6  285  50 26   4.0   2.2 |  -5.4  22.3  275  44 23   2.2   1.2
 10500  -3.6  25.5  285  48 24   4.2   2.3 |  -5.0  23.0  275  42 21   3.3   1.8
 10250  -3.3  26.1  285  46 24   4.4   2.4 |  -4.8  23.4  280  39 20   3.5   1.9
 10000  -3.0  26.6  285  44 23   3.7   2.0 |  -4.5  23.9  280  37 19   3.8   2.1
  9750  -2.7  27.1  285  42 22   4.0   2.2 |  -4.2  24.4  280  34 18   5.1   2.8
  9500  -2.4  27.7  285  39 20   5.2   2.8 |  -3.8  25.2  280  31 16   6.2   3.4
  9250  -2.0  28.4  285  36 19   5.6   3.1 |  -3.4  25.9  280  28 15   6.3   3.4
  9000  -1.6  29.1  285  33 17   4.4   2.4 |  -2.9  26.8  280  25 13   6.3   3.5
  8750  -1.3  29.7  285  31 16   4.8   2.6 |  -2.4  27.7  285  23 12   7.1   3.9
  8500  -0.8  30.6  285  28 14   6.6   3.6 |  -1.9  28.6  285  21 11   7.8   4.3
  8250  -0.4  31.3  285  25 13   5.7   3.1 |  -1.3  29.7  285  18  9   7.1   3.9
  8000   0.1  32.2  285  22 11   7.9   4.3 |  -0.7  30.7  285  16  8   8.9   4.9
  7750   0.8  33.4  285  20 10   8.2   4.5 |  -0.0  32.0  285  13  7   8.8   4.9
  7500   1.3  34.3  285  17  9   6.3   3.5 |   0.5  32.9  285  11  6   7.1   3.9
  7250   1.8  35.2  285  15  8   6.8   3.7 |   1.1  34.0  290   9  5   7.4   4.1
  7000   2.3  36.1  285  12  6   6.8   3.7 |   1.7  35.1  295   7  4   7.9   4.3
  6750   2.8  37.0  285  11  6   7.2   4.0 |   2.3  36.1  295   7  3   9.0   4.9
  6500   3.4  38.1  285   9  5   7.7   4.3 |   3.0  37.4  300   6  3   9.1   5.0
  6250   3.9  39.0  280   7  4   6.5   3.6 |   3.7  38.7  300   5  3   9.3   5.1
  6000   4.1  39.4  270   5  3  -2.1  -1.1 |   4.4  39.9  305   5  2  10.3   5.7
  5750   3.9  39.0  250   4  2  -0.4  -0.2 |   5.2  41.4  305   4  2   9.7   5.3
  5500   3.8  38.8  205   4  2  -8.6  -4.7 |   5.9  42.6  305   4  2  11.4   6.2

           12/05/2016 at 1400 MST          |       12/05/2016 at 1700 MST
                                           |
K index... -28.5  LI... +4.5               | K index... -13.1  LI... +4.3
CAPE... 0.0  CIN... -0.9                   | 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 -58.5 -73.3  245  43 22   1.0   0.5 | -60.7 -77.3  255  37 19   2.3   1.3
 45000 -57.0 -70.6  255  81 42   1.0   0.6 | -57.0 -70.6  255  85 44   2.3   1.3
 40000 -58.5 -73.3  265  67 35  -1.3  -0.7 | -57.4 -71.3  265  73 38  -0.7  -0.4
 38000 -58.9 -74.0  270  60 31   3.9   2.1 | -57.7 -71.9  270  66 34   1.1   0.6
 36000 -56.8 -70.2  260  68 35   3.5   1.9 | -56.8 -70.2  265  75 39   1.5   0.8
 34000 -54.4 -65.9  250  78 40   3.4   1.8 | -55.9 -68.6  255  85 44   1.6   0.9
 32000 -51.5 -60.7  255  80 41   5.1   2.8 | -52.5 -62.5  255  86 44   6.3   3.4
 30000 -48.4 -55.1  265  82 42   5.5   3.0 | -48.7 -55.7  260  83 43   6.2   3.4
 29000 -46.0 -50.8  265  82 42   8.7   4.8 | -46.5 -51.7  260  79 41   7.9   4.3
 28000 -43.4 -46.1  265  82 42   8.6   4.7 | -44.1 -47.4  260  75 39   7.9   4.3
 27000 -40.8 -41.4  265  82 42   8.6   4.7 | -41.7 -43.1  260  71 37   7.9   4.3
 26000 -38.4 -37.1  265  80 41   6.9   3.8 | -39.4 -38.9  260  68 35   7.6   4.2
 25000 -36.3 -33.3  265  76 39   6.9   3.8 | -37.1 -34.8  265  68 35   7.6   4.2
 24000 -34.2 -29.6  270  72 37   6.9   3.8 | -34.8 -30.6  270  67 35   7.7   4.2
 23000 -32.2 -26.0  270  68 35   6.1   3.3 | -32.6 -26.7  270  67 35   5.4   2.9
 22000 -30.4 -22.7  270  64 33   6.1   3.4 | -30.9 -23.6  275  66 34   5.6   3.1
 21000 -28.5 -19.3  275  60 31   6.2   3.4 | -29.2 -20.6  275  64 33   5.7   3.1
 20000 -26.5 -15.7  270  55 29   7.3   4.0 | -27.5 -17.5  275  62 32   6.2   3.4
 19500 -25.4 -13.7  270  54 28   7.4   4.0 | -26.6 -15.9  275  61 31   6.2   3.4
 19000 -24.3 -11.7  270  52 27   7.4   4.0 | -25.6 -14.1  275  60 31   6.2   3.4
 18500 -23.2  -9.8  265  50 26   7.4   4.1 | -24.7 -12.5  270  59 31   6.2   3.4
 18000 -21.4  -6.5  265  47 24   9.6   5.3 | -23.8 -10.8  270  58 30   6.6   3.6
 17500 -20.0  -4.0  260  45 23   9.4   5.2 | -22.7  -8.9  270  58 30   7.5   4.1
 17000 -18.5  -1.3  260  43 22   8.6   4.7 | -21.0  -5.8  270  57 29   7.8   4.3
 16500 -17.4   0.7  260  43 22   8.0   4.4 | -19.8  -3.6  265  55 28   8.0   4.4
 16000 -16.2   2.8  265  44 22   7.8   4.3 | -18.6  -1.5  265  53 27   7.9   4.4
 15500 -15.0   5.0  265  43 22   7.2   3.9 | -17.5   0.5  265  50 26   7.2   3.9
 15000 -14.0   6.8  265  42 21   7.3   4.0 | -16.4   2.5  265  48 24   7.4   4.1
 14500 -12.9   8.8  265  42 22   6.2   3.4 | -15.4   4.3  265  44 23   5.4   3.0
 14000 -12.0  10.4  270  44 23   6.4   3.5 | -14.6   5.7  265  40 21   5.7   3.1
 13500 -11.1  12.0  270  45 23   5.3   2.9 | -13.9   7.0  260  35 18   3.9   2.1
 13000 -10.3  13.5  270  43 22   5.3   2.9 | -13.4   7.9  260  29 15   3.6   2.0
 12500  -9.6  14.7  270  40 21   4.9   2.7 | -12.7   9.1  255  24 12   6.8   3.7
 12000  -8.9  16.0  270  38 19   4.8   2.6 | -11.6  11.1  250  20 10   7.4   4.1
 11500  -8.1  17.4  275  34 18   5.5   3.0 | -10.5  13.1  240  17  9   8.4   4.6
 11000  -7.3  18.9  275  28 15   5.7   3.1 |  -9.2  15.4  240  13  7   8.6   4.7
 10500  -6.4  20.5  275  23 12   7.3   4.0 |  -7.9  17.8  240  11  6   8.4   4.6
 10250  -5.9  21.4  275  21 11   7.5   4.1 |  -7.3  18.9  240  10  5   7.7   4.2
 10000  -5.3  22.5  280  19 10   8.6   4.7 |  -6.7  19.9  245   9  4  10.0   5.5
  9750  -4.6  23.7  280  17  9   9.7   5.3 |  -5.9  21.4  250   7  4  10.7   5.9
  9500  -3.9  25.0  280  16  8   9.4   5.2 |  -5.2  22.6  260   6  3   8.4   4.6
  9250  -3.2  26.2  285  14  7   9.9   5.4 |  -4.5  23.9  280   5  3   8.9   4.9
  9000  -2.5  27.5  285  13  7   8.5   4.7 |  -3.9  25.0  300   5  3   8.0   4.4
  8750  -1.9  28.6  290  12  6   8.7   4.8 |  -3.3  26.1  315   6  3   7.6   4.2
  8500  -1.2  29.8  290  12  6  10.4   5.7 |  -2.7  27.1  330   7  3   8.2   4.5
  8250  -0.4  31.3  290  12  6   9.6   5.3 |  -2.1  28.2  340   8  4   7.7   4.2
  8000   0.3  32.5  295  11  6  11.1   6.1 |  -1.5  29.3  350   9  5   9.2   5.0
  7750   1.2  34.2  295  11  6  10.6   5.8 |  -0.8  30.6  355  11  6   8.6   4.7
  7500   1.9  35.4  295  11  6   8.9   4.9 |  -0.3  31.5  360  12  6   6.8   3.7
  7250   2.5  36.5  295  11  5   9.3   5.1 |   0.2  32.4  005  14  7   7.2   4.0
  7000   3.2  37.8  300  10  5   9.2   5.0 |   0.8  33.4  010  15  8   7.7   4.2
  6750   3.9  39.0  300  10  5   9.7   5.3 |   1.4  34.5  010  16  8   8.0   4.4
  6500   4.7  40.5  300  10  5  10.2   5.6 |   2.0  35.6  015  18  9   7.9   4.3
  6250   5.4  41.7  305  10  5  10.0   5.5 |   2.5  36.5  015  19 10   7.3   4.0
  6000   6.2  43.2  305  10  5  10.2   5.6 |   3.0  37.4  020  19 10   6.5   3.5
  5750   6.9  44.4  305   9  5   9.2   5.0 |   3.5  38.3  020  19 10   5.8   3.2
  5500   7.6  45.7  305   8  4  11.0   6.0 |   3.8  38.8  025  14  7   0.9   0.5
________________________________________________________________________________

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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