Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 080054
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1754 MST Sunday, February 7, 2016

This forecast is for Monday, February 8, 2016:

If the trigger temperature of 45.8 F/7.7 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 398 ft/min (2.0 m/s)
   Maximum height of thermals.................. 11130 ft MSL (5823 ft AGL)

Forecast maximum temperature................... 52.0 F/11.6 C
Time of trigger temperature.................... 1100 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9461 ft MSL (4154 ft AGL)
Thermal soaring outlook for Tuesday 02/09...... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 13437 ft MSL (8130 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 15161 ft MSL (9854 ft AGL)
Wave soaring outlook for Tuesday 02/09......... Poor

Remarks... Strong north-northwest flow aloft shifts east of colorado by late on
           Monday.

Sunrise/Sunset.................... 07:00:34 / 17:25:46 MST
Total possible sunshine........... 10 hr 25 min 13 sec (625 min 13 sec)
Altitude of sun at 12:13:31 MST... 35.29 degrees

Upper air data from numerical model forecast valid on 02/08/2016 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 18365 ft MSL (13058 ft AGL)
Lifted condensation level....... 14275 ft MSL (8969 ft AGL)
Lifted index.................... +8.0
K index......................... +1.6

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -56.3 -69.3   335   43   22   1.3   0.7      M     M       M      M    M
 45000  -54.3 -65.7   335   54   28  -0.1  -0.0      M     M       M      M    M
 40000  -59.0 -74.2   345   75   39  -3.2  -1.7      M     M       M      M    M
 38000  -59.5 -75.1   345   81   42   2.5   1.4      M     M       M      M    M
 36000  -58.0 -72.4   340   82   42   2.5   1.4      M     M       M      M    M
 34000  -55.8 -68.4   335   83   43   6.5   3.6      M     M       M      M    M
 32000  -51.9 -61.4   340   76   39   6.5   3.5      M     M       M      M    M
 30000  -47.5 -53.5   340   71   37   9.3   5.1   28.0  82.4    12.6      M    M
 29000  -44.7 -48.5   345   71   36   9.4   5.2   27.8  82.0    12.6      M    M
 28000  -41.9 -43.4   345   70   36   9.4   5.2   27.7  81.8    12.7      M    M
 27000  -39.1 -38.4   350   70   36   8.6   4.7   27.6  81.8    12.8      M    M
 26000  -36.6 -33.9   350   70   36   8.3   4.6   27.0  80.6    12.5      M    M
 25000  -34.1 -29.4   355   71   36   8.3   4.6   26.4  79.6    12.2      M    M
 24000  -31.6 -24.9   360   71   37   8.1   4.5   26.0  78.9    12.0      M    M
 23000  -29.2 -20.6   355   70   36   7.9   4.3   25.2  77.4    11.5      M    M
 22000  -26.9 -16.4   350   69   36   7.9   4.3   24.6  76.3    11.1      M    M
 21000  -24.5 -12.1   350   69   35   8.4   4.6   24.0  75.2    10.7      M    M
 20000  -21.9  -7.4   350   66   34   8.4   4.6   23.5  74.3    10.4      M    M
 19500  -20.7  -5.3   350   65   34   8.4   4.6   23.3  73.9    10.3      M    M
 19000  -19.4  -2.9   350   64   33   8.4   4.6   23.1  73.5    10.2      M    M
 18500  -18.2  -0.8   350   63   32   8.5   4.7   22.9  73.2    10.0      M    M
 18000  -16.9   1.6   350   60   31   8.5   4.7   22.6  72.8     9.9      M    M
 17500  -15.0   5.0   345   57   29   8.1   4.4   22.3  72.2     9.7      M    M
 17000  -13.8   7.2   340   54   28   7.9   4.3   22.0  71.6     9.5      M    M
 16500  -12.6   9.3   340   52   27   6.8   3.7   21.7  71.1     9.2      M    M
 16000  -11.9  10.6   340   56   29   5.1   2.8   20.9  69.7     8.6      M    M
 15500  -11.1  12.0   340   60   31   4.9   2.7   20.1  68.3     7.9      M    M
 15000  -10.6  12.9   340   61   31   3.4   1.8   19.2  66.5     7.0      M    M
 14500  -10.1  13.8   340   60   31   3.5   1.9   18.1  64.6     6.1      M    M
 14000   -9.6  14.7   340   60   31   3.1   1.7   17.1  62.7     5.1      M    M
 13500   -9.1  15.6   340   59   31   3.1   1.7   16.0  60.8     4.1      M    M
 13000   -8.6  16.5   340   59   30   3.9   2.2   14.9  58.9     3.2      M    M
 12500   -8.1  17.4   345   58   30   3.9   2.2   14.0  57.2     2.3      M    M
 12000   -7.5  18.5   345   57   29   3.8   2.1   13.1  55.5     1.5      M    M
 11500   -6.9  19.6   345   56   29   3.7   2.0   12.1  53.8     0.6      M    M
 11000   -6.3  20.7   345   53   28   4.6   2.5   11.2  52.1    -0.3    387  2.0
 10500   -5.6  21.9   345   49   25   4.8   2.6   10.4  50.6    -1.0    352  1.8
 10250   -5.3  22.5   345   47   24   3.6   2.0    9.9  49.9    -1.4    334  1.7
 10000   -5.1  22.8   345   45   23   2.5   1.4    9.4  48.9    -2.0    321  1.6
  9750   -4.8  23.4   340   42   22   3.4   1.9    8.9  47.9    -2.5    307  1.6
  9500   -4.6  23.7   340   38   19   3.7   2.0    8.4  47.1    -2.9    291  1.5
  9250   -4.3  24.3   340   34   17   3.8   2.1    7.9  46.2    -3.4    275  1.4
  9000   -4.0  24.8   340   31   16   3.6   2.0    7.4  45.4    -3.9    260  1.3
  8750   -3.7  25.3   335   28   15   4.9   2.7    7.0  44.6    -4.3    243  1.2
  8500   -3.3  26.1   335   26   13   5.0   2.7    6.6  44.0    -4.6    224  1.1
  8250   -3.0  26.6   330   24   13   3.2   1.8    6.2  43.1    -5.1    208  1.1
  8000   -2.8  27.0   325   24   12   3.6   2.0    5.7  42.2    -5.6    193  1.0
  7750   -2.5  27.5   320   23   12   2.6   1.4    5.2  41.4    -6.1    178  0.9
  7500   -2.4  27.7   320   22   11   2.6   1.4    4.6  40.3    -6.7    166  0.8
  7250   -2.1  28.2   315   20   10   3.5   1.9    4.1  39.4    -7.2    151  0.8
  7000   -1.9  28.6   315   18    9   3.4   1.9    3.6  38.5    -7.7    136  0.7
  6750   -1.6  29.1   315   16    8   2.9   1.6    3.1  37.7    -8.2    121  0.6
  6500   -1.4  29.5   315   14    7   2.2   1.2    2.6  36.6    -8.8    109  0.6
  6250   -1.2  29.8   310   11    6   4.8   2.6    2.1  35.7    -9.3     95  0.5
  6000   -1.0  30.2   310    8    4  -2.8  -1.6    1.6  34.8    -9.8     80  0.4
  5750   -2.2  28.0   285    5    3 -31.8 -17.4   -0.4  31.4   -11.8    109  0.6
  5500   -5.7  21.7   235    3    2 -57.8 -31.7   -4.6  23.7   -16.0    206  1.0

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

           02/08/2016 at 0800 MST          |       02/08/2016 at 1100 MST
                                           |
K index... +8.2  LI... +6.8                | K index... +9.0  LI... +5.4
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -1.1
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -56.2 -69.2  335  43 22   1.3   0.7 | -56.0 -68.8  340  46 24   1.4   0.8
 45000 -54.2 -65.6  340  54 28   0.3   0.2 | -53.9 -65.0  340  53 27   0.2   0.1
 40000 -56.5 -69.7  350  76 39  -1.6  -0.9 | -61.3 -78.3  005  89 46  -4.8  -2.7
 38000 -57.3 -71.1  355  84 43  -0.6  -0.4 | -61.7 -79.1  005  94 48   3.2   1.8
 36000 -57.7 -71.9  360  90 46  -0.7  -0.4 | -59.7 -75.5  005  89 46   3.2   1.8
 34000 -57.0 -70.6  005  95 49   7.9   4.3 | -57.1 -70.8  005  86 44   9.0   4.9
 32000 -52.2 -62.0  360  88 45   7.9   4.3 | -51.7 -61.1  010  88 45   8.9   4.9
 30000 -47.2 -53.0  355  83 43   9.1   5.0 | -46.4 -51.5  010  90 46   9.1   5.0
 29000 -44.5 -48.1  355  81 42   9.1   5.0 | -43.0 -45.4  010  88 45   9.1   5.0
 28000 -41.8 -43.2  355  79 41   9.1   5.0 | -40.3 -40.5  010  87 45   9.1   5.0
 27000 -39.1 -38.4  355  77 39   8.7   4.7 | -37.6 -35.7  010  84 43   8.8   4.8
 26000 -36.5 -33.7  350  71 36   8.5   4.7 | -34.9 -30.8  005  77 39   8.8   4.8
 25000 -34.0 -29.2  350  65 33   8.5   4.7 | -32.3 -26.1  360  70 36   8.8   4.8
 24000 -31.4 -24.5  350  59 30   7.9   4.3 | -29.7 -21.5  350  65 34   8.1   4.4
 23000 -29.2 -20.6  350  59 30   7.4   4.0 | -27.3 -17.1  350  63 33   8.0   4.4
 22000 -27.0 -16.6  345  59 31   7.4   4.0 | -24.9 -12.8  350  62 32   8.0   4.4
 21000 -24.7 -12.5  345  58 30   9.3   5.1 | -22.8  -9.0  345  59 30   5.7   3.1
 20000 -22.0  -7.6  335  50 26   9.2   5.0 | -21.0  -5.8  340  55 28   5.9   3.2
 19500 -20.6  -5.1  335  47 24   9.2   5.0 | -20.2  -4.4  340  53 27   5.9   3.2
 19000 -19.2  -2.6  330  43 22   9.3   5.1 | -19.3  -2.7  335  51 26   5.6   3.1
 18500 -17.9  -0.2  325  42 22   7.8   4.3 | -18.3  -0.9  335  50 26   8.6   4.7
 18000 -16.2   2.8  330  45 23   7.7   4.2 | -17.0   1.4  335  49 25   8.3   4.6
 17500 -15.1   4.8  335  47 24   6.4   3.5 | -15.8   3.6  335  49 25   7.7   4.2
 17000 -14.2   6.4  335  50 26   6.3   3.4 | -14.7   5.5  335  48 25   7.2   3.9
 16500 -13.3   8.1  340  52 27   5.7   3.1 | -13.7   7.3  335  48 25   7.0   3.9
 16000 -12.5   9.5  345  56 29   5.1   2.8 | -12.7   9.1  335  49 25   5.8   3.2
 15500 -11.8  10.8  345  61 31   4.9   2.7 | -11.9  10.6  340  50 26   5.9   3.2
 15000 -11.2  11.8  350  61 31   3.9   2.1 | -10.7  12.7  345  51 26   5.4   3.0
 14500 -10.6  12.9  350  60 31   4.0   2.2 |  -9.9  14.2  345  51 26   5.3   2.9
 14000 -10.2  13.6  350  58 30   2.7   1.5 |  -9.2  15.4  345  51 26   4.0   2.2
 13500  -9.8  14.4  350  56 29   2.6   1.5 |  -8.6  16.5  345  50 26   4.1   2.3
 13000  -9.2  15.4  345  55 28   4.4   2.4 |  -8.0  17.6  345  50 26   3.9   2.2
 12500  -8.6  16.5  350  54 28   4.1   2.2 |  -7.5  18.5  345  50 25   3.9   2.1
 12000  -7.8  18.0  345  53 27   6.4   3.5 |  -6.8  19.8  350  49 25   5.6   3.1
 11500  -6.9  19.6  345  54 28   6.2   3.4 |  -6.0  21.2  350  49 25   5.4   3.0
 11000  -5.9  21.4  345  53 27   7.4   4.0 |  -5.0  23.0  350  49 25   7.3   4.0
 10500  -4.8  23.4  345  52 27   7.3   4.0 |  -4.0  24.8  350  49 25   7.0   3.8
 10250  -4.3  24.3  345  51 26   5.3   2.9 |  -3.5  25.7  350  48 25   5.5   3.0
 10000  -4.0  24.8  345  50 26   4.0   2.2 |  -3.1  26.4  350  48 24   5.3   2.9
  9750  -3.6  25.5  345  48 25   5.4   2.9 |  -2.6  27.3  345  45 23   6.9   3.8
  9500  -3.2  26.2  345  45 23   5.0   2.8 |  -2.1  28.2  345  43 22   5.7   3.1
  9250  -2.9  26.8  345  41 21   3.3   1.8 |  -1.8  28.8  345  40 20   3.2   1.7
  9000  -2.7  27.1  345  38 20   2.6   1.4 |  -1.6  29.1  345  37 19   2.8   1.5
  8750  -2.5  27.5  345  35 18   3.4   1.9 |  -1.3  29.7  345  33 17   4.7   2.6
  8500  -2.2  28.0  340  30 15   4.5   2.4 |  -0.9  30.4  340  29 15   6.0   3.3
  8250  -1.8  28.8  340  27 14   4.8   2.6 |  -0.5  31.1  340  27 14   5.7   3.2
  8000  -1.4  29.5  335  25 13   4.7   2.6 |  -0.0  32.0  335  24 12   5.7   3.1
  7750  -1.1  30.0  335  23 12   5.1   2.8 |   0.4  32.7  335  22 11   6.2   3.4
  7500  -0.7  30.7  330  22 11   3.2   1.8 |   0.8  33.4  330  21 11   4.8   2.6
  7250  -0.6  30.9  325  22 11   1.3   0.7 |   1.1  34.0  325  20 10   3.3   1.8
  7000  -0.5  31.1  320  22 11   2.0   1.1 |   1.4  34.5  325  20 10   3.5   1.9
  6750  -0.3  31.5  315  22 11   0.8   0.4 |   1.6  34.9  320  20 10   2.4   1.3
  6500  -0.4  31.3  315  18 10  -0.6  -0.3 |   1.7  35.1  320  17  9   1.8   1.0
  6250  -0.4  31.3  315  16  8   0.9   0.5 |   1.9  35.4  320  15  8   3.8   2.1
  6000  -0.4  31.3  315  13  6  -3.9  -2.2 |   2.1  35.8  320  13  6  -2.2  -1.2
  5750  -1.4  29.5  305   9  5 -25.7 -14.1 |   1.5  34.7  310   8  4 -11.2  -6.2
  5500  -4.3  24.3  275   4  2 -47.8 -26.2 |   0.6  33.1  300   3  2  -8.7  -4.8

           02/08/2016 at 1400 MST          |       02/08/2016 at 1700 MST
                                           |
K index... +12.4  LI... +6.6               | K index... +5.2  LI... +6.9
CAPE... 0.0  CIN... -0.9                   | CAPE... 0.0  CIN... -0.5
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -56.3 -69.3  340  48 25   1.7   0.9 | -57.5 -71.5  340  51 26   1.6   0.9
 45000 -53.7 -64.7  340  55 28   0.2   0.1 | -55.2 -67.4  340  60 31  -0.2  -0.1
 40000 -61.8 -79.2  360  79 41  -5.3  -2.9 | -62.3 -80.1  005  82 42  -4.6  -2.5
 38000 -62.1 -79.8  360  81 41   4.0   2.2 | -61.9 -79.4  360  81 41   4.5   2.5
 36000 -59.7 -75.5  355  75 39   4.0   2.2 | -59.2 -74.6  355  71 37   4.5   2.5
 34000 -56.6 -69.9  350  71 37   8.7   4.8 | -55.8 -68.4  345  65 34   8.8   4.8
 32000 -51.4 -60.5  350  71 37   8.7   4.8 | -50.4 -58.7  350  66 34   9.0   4.9
 30000 -46.0 -50.8  350  70 36  10.1   5.5 | -45.0 -49.0  355  64 33   9.5   5.2
 29000 -42.2 -44.0  350  68 35  10.1   5.6 | -41.4 -42.5  350  59 31   9.5   5.2
 28000 -39.1 -38.4  345  67 35  10.1   5.6 | -38.6 -37.5  345  56 29   9.5   5.2
 27000 -36.3 -33.3  345  66 34   8.2   4.5 | -35.9 -32.6  340  54 28   7.8   4.3
 26000 -33.7 -28.7  345  64 33   8.4   4.6 | -33.5 -28.3  345  53 27   7.9   4.4
 25000 -31.2 -24.2  345  63 32   8.4   4.6 | -31.2 -24.2  350  52 27   7.9   4.4
 24000 -28.7 -19.7  345  61 31   8.4   4.6 | -28.7 -19.7  350  51 26   9.0   5.0
 23000 -26.2 -15.2  345  60 31   8.4   4.6 | -26.0 -14.8  355  49 25   9.0   4.9
 22000 -23.7 -10.7  340  60 31   8.4   4.6 | -23.3  -9.9  355  47 24   9.0   4.9
 21000 -21.4  -6.5  340  59 31   6.2   3.4 | -20.9  -5.6  355  47 24   6.7   3.7
 20000 -19.5  -3.1  345  59 31   6.4   3.5 | -18.9  -2.0  355  50 26   6.8   3.7
 19500 -18.6  -1.5  345  60 31   6.4   3.5 | -17.9  -0.2  355  52 27   6.8   3.8
 19000 -17.7   0.1  345  60 31   6.7   3.7 | -16.9   1.6  355  54 28   7.1   3.9
 18500 -16.9   1.6  345  59 30   3.1   1.7 | -16.0   3.2  355  56 29   4.5   2.5
 18000 -16.4   2.5  345  58 30   3.3   1.8 | -15.3   4.5  355  57 29   4.7   2.6
 17500 -16.0   3.2  350  57 29   3.7   2.1 | -14.6   5.7  355  58 30   4.5   2.5
 17000 -15.4   4.3  350  55 28   4.3   2.4 | -14.0   6.8  355  58 30   4.3   2.3
 16500 -14.7   5.5  350  54 28   4.4   2.4 | -13.3   8.1  355  58 30   4.3   2.4
 16000 -14.1   6.6  350  53 27   4.7   2.6 | -12.6   9.3  355  57 29   5.7   3.1
 15500 -13.1   8.4  350  51 26   5.3   2.9 | -11.8  10.8  355  56 29   5.6   3.1
 15000 -12.2  10.0  350  50 26   6.5   3.6 | -10.5  13.1  355  53 27   5.9   3.2
 14500 -11.2  11.8  350  49 25   6.4   3.5 |  -9.6  14.7  355  52 27   5.9   3.2
 14000 -10.4  13.3  350  47 24   5.3   2.9 |  -8.7  16.3  355  50 26   6.3   3.4
 13500  -9.6  14.7  350  46 24   5.4   3.0 |  -7.8  18.0  355  48 25   6.3   3.5
 13000  -8.8  16.2  350  45 23   4.9   2.7 |  -7.0  19.4  355  47 24   4.9   2.7
 12500  -8.1  17.4  345  44 22   4.8   2.7 |  -6.3  20.7  350  45 23   5.1   2.8
 12000  -7.2  19.0  345  42 22   7.4   4.1 |  -5.5  22.1  350  43 22   5.4   3.0
 11500  -6.1  21.0  345  41 21   7.2   4.0 |  -4.8  23.4  350  41 21   5.3   2.9
 11000  -5.0  23.0  345  40 21   7.5   4.1 |  -3.9  25.0  350  40 20   6.9   3.8
 10500  -3.9  25.0  345  40 21   7.3   4.0 |  -2.9  26.8  350  39 20   6.7   3.7
 10250  -3.4  25.9  345  40 20   5.7   3.1 |  -2.4  27.7  350  38 20   5.1   2.8
 10000  -3.0  26.6  345  39 20   5.6   3.1 |  -2.1  28.2  350  38 19   5.5   3.0
  9750  -2.5  27.5  345  37 19   7.6   4.2 |  -1.6  29.1  345  36 18   7.5   4.1
  9500  -2.0  28.4  340  34 18   6.8   3.7 |  -1.1  30.0  345  34 17   6.8   3.7
  9250  -1.6  29.1  340  32 16   4.8   2.6 |  -0.6  30.9  345  31 16   5.3   2.9
  9000  -1.2  29.8  340  30 15   4.5   2.5 |  -0.3  31.5  340  29 15   5.2   2.9
  8750  -0.8  30.6  335  28 14   6.3   3.5 |   0.2  32.4  340  26 13   6.8   3.8
  8500  -0.3  31.5  335  25 13   6.5   3.6 |   0.7  33.3  335  23 12   7.6   4.2
  8250   0.1  32.2  335  23 12   5.5   3.0 |   1.3  34.3  335  22 11   7.4   4.1
  8000   0.5  32.9  330  21 11   5.6   3.1 |   1.8  35.2  330  21 11   7.4   4.1
  7750   0.9  33.6  330  19 10   6.4   3.5 |   2.4  36.3  325  20 10   8.4   4.6
  7500   1.4  34.5  325  17  9   5.8   3.2 |   3.0  37.4  325  19 10   7.5   4.1
  7250   1.8  35.2  325  16  8   4.6   2.5 |   3.5  38.3  320  19 10   6.0   3.3
  7000   2.1  35.8  330  14  7   4.6   2.5 |   4.0  39.2  320  19 10   6.7   3.7
  6750   2.4  36.3  330  13  6   0.8   0.4 |   4.4  39.9  315  18  9   5.4   3.0
  6500   2.3  36.1  330  10  5  -1.1  -0.6 |   4.7  40.5  310  16  8   3.0   1.7
  6250   2.3  36.1  335   8  4   0.5   0.3 |   5.0  41.0  310  14  7   4.0   2.2
  6000   2.3  36.1  345   6  3  -1.5  -0.8 |   5.2  41.4  300  12  6  -0.4  -0.2
  5750   2.0  35.6  340   2  1  -6.1  -3.3 |   4.6  40.3  285   9  5 -16.3  -8.9
  5500   1.3  34.3  000   0  0  -8.7  -4.8 |   2.8  37.0  255   5  3 -29.0 -15.9
________________________________________________________________________________

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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