Soaring Guidance
Issued by NWS Denver/Boulder, CO

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720
UXUS97 KBOU 011318
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0618 MST Monday, February 1, 2016

This forecast is for Monday, February 1, 2016:

If the trigger temperature of 33.4 F/0.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6245 ft MSL (960 ft AGL)

Forecast maximum temperature................... 28.0 F/-2.7 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. None
Thermal soaring outlook for Tuesday 02/02...... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Decreasing
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 17592 ft MSL (12307 ft AGL)
Wave soaring outlook for Tuesday 02/02......... Poor

Remarks...

Sunrise/Sunset.................... 07:07:38 / 17:17:26 MST
Total possible sunshine........... 10 hr 9 min 47 sec (609 min 47 sec)
Altitude of sun at 12:12:55 MST... 33.19 degrees

Upper air data from rawinsonde observation taken on 02/01/2016 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 14879 ft MSL (9594 ft AGL)
Lifted condensation level....... 8441 ft MSL (3156 ft AGL)
Lifted index.................... +12.8
K index......................... +5.8

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -53.2 -63.8   255   66   34   5.3   2.9  111.8 233.2    65.1      M    M
 45000  -46.9 -52.4   250   58   30   7.0   3.8   96.4 205.6    60.4      M    M
 40000  -41.9 -43.4   240   66   34   6.1   3.4   81.3 178.3    54.5      M    M
 38000  -42.3 -44.1   240   74   38  -8.5  -4.6   71.8 161.2    49.5      M    M
 36000  -44.6 -48.3   245   72   37   1.6   0.9   59.8 139.7    42.6      M    M
 34000  -49.9 -57.8   245   64   33  -6.4  -3.5   43.8 110.9    32.4      M    M
 32000  -49.5 -57.1   240   51   26 -12.4  -6.8   36.2  97.1    27.8      M    M
 30000  -52.3 -62.1   255   45   23   4.9   2.7   23.4  74.0    19.1      M    M
 29000  -50.5 -58.9   250   40   20   0.9   0.5   21.7  71.1    18.1      M    M
 28000  -49.0 -56.2   235   33   17   7.9   4.4   20.0  67.9    17.0      M    M
 27000  -46.3 -51.3   235   33   17   9.2   5.1   19.6  67.3    16.9      M    M
 26000  -43.5 -46.3   230   34   17   9.2   5.1   19.4  67.0    17.0      M    M
 25000  -40.7 -41.3   230   34   17   9.2   5.1   19.3  66.8    17.1      M    M
 24000  -37.9 -36.2   230   32   17   9.8   5.4   19.2  66.6    17.2      M    M
 23000  -35.0 -31.0   230   31   16   8.9   4.9   19.2  66.5    17.4      M    M
 22000  -32.3 -26.1   235   31   16   8.9   4.9   18.8  65.9    17.3      M    M
 21000  -29.7 -21.5   235   30   16   8.5   4.7   18.6  65.4    17.3      M    M
 20000  -27.3 -17.1   240   30   15   8.1   4.5   18.0  64.4    17.1      M    M
 19500  -26.0 -14.8   240   31   16   8.1   4.5   17.7  63.9    16.9      M    M
 19000  -24.8 -12.6   245   33   17   8.1   4.5   17.4  63.3    16.7      M    M
 18500  -23.6 -10.5   245   35   18   8.1   4.5   17.1  62.8    16.6      M    M
 18000  -22.4  -8.3   245   37   19   7.9   4.3   16.9  62.4    16.4      M    M
 17500  -21.1  -6.0   245   37   19   8.9   4.9   16.6  61.9    16.3      M    M
 17000  -19.8  -3.6   245   38   20   8.8   4.8   16.5  61.6    16.3      M    M
 16500  -18.7  -1.7   245   37   19   6.9   3.8   16.1  61.0    16.1      M    M
 16000  -17.6   0.3   240   35   18   7.1   3.9   15.7  60.2    15.7      M    M
 15500  -16.6   2.1   240   34   17   6.5   3.6   15.2  59.4    15.4      M    M
 15000  -14.7   5.5   240   31   16   9.4   5.2   14.9  58.8    15.2      M    M
 14500  -13.3   8.1   240   29   15   8.0   4.4   14.9  58.8    15.2      M    M
 14000  -12.4   9.7   240   28   14   6.7   3.7   14.3  57.8    14.8      M    M
 13500  -11.5  11.3   245   26   13   4.6   2.5   13.7  56.6    14.3      M    M
 13000  -10.8  12.6   250   24   12   4.5   2.5   12.8  55.1    13.6      M    M
 12500  -10.2  13.6   245   23   12   3.8   2.1   11.9  53.4    12.8      M    M
 12000   -9.7  14.5   240   22   11   3.9   2.2   10.9  51.7    11.9      M    M
 11500   -9.0  15.8   235   19   10   7.0   3.8   10.2  50.3    11.2      M    M
 11000   -8.9  16.0   225   16    8  -6.3  -3.5    8.8  47.8    10.0      M    M
 10500   -9.9  14.2   215   14    7  -7.3  -4.0    6.1  43.0     7.5      M    M
 10250  -10.6  12.9   210   13    7 -13.1  -7.2    4.6  40.3     6.1      M    M
 10000  -11.5  11.3   205   12    6  -8.5  -4.7    2.8  37.0     4.4      M    M
  9750  -11.7  10.9   195   13    7   2.7   1.5    1.9  35.4     3.6      M    M
  9500  -11.4  11.5   185   15    8   4.3   2.3    1.4  34.6     3.2      M    M
  9250  -11.1  12.0   180   19   10   4.3   2.4    1.0  33.8     2.8      M    M
  9000  -10.7  12.7   175   23   12   4.3   2.4    0.6  33.1     2.4      M    M
  8750  -10.4  13.3   175   22   11   4.3   2.4    0.2  32.3     2.0      M    M
  8500  -10.1  13.8   175   20   11   4.4   2.4   -0.3  31.5     1.5      M    M
  8250   -9.8  14.4   175   19   10   4.0   2.2   -0.7  30.8     1.1      M    M
  8000   -9.5  14.9   175   18    9   6.5   3.6   -1.1  30.1     0.8      M    M
  7750   -8.8  16.2   170   18    9   8.7   4.8   -1.2  29.9     0.7      M    M
  7500   -8.2  17.2   170   18    9   8.1   4.5   -1.3  29.7     0.5      M    M
  7250   -7.6  18.3   165   19   10   8.3   4.6   -1.4  29.5     0.4      M    M
  7000   -7.0  19.4   165   19   10   8.3   4.5   -1.5  29.3     0.3      M    M
  6750   -6.4  20.5   165   16    8   8.3   4.5   -1.6  29.1     0.2      M    M
  6500   -5.7  21.7   165   13    7   8.2   4.5   -1.7  28.9     0.1      M    M
  6250   -5.1  22.8   165   10    5   8.3   4.6   -1.8  28.7     0.0      M    M
  6000   -4.5  23.9   170    6    3   7.9   4.3   -1.9  28.5    -0.1      M    M
  5750   -3.9  25.0   170    4    2   9.5   5.2   -2.1  28.3    -0.2      M    M
  5500   -3.3  26.1   170    2    1   3.6   2.0   -2.2  28.1    -0.4      M    M

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

           02/01/2016 at 0800 MST          |       02/01/2016 at 1100 MST
                                           |
K index... +14.0  LI... +3.3               | K index... +13.6  LI... +4.6
CAPE... 0.0  CIN... -0.1                   | CAPE... +10.0  CIN... -0.7
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -51.3 -60.3  255  50 26   4.0   2.2 | -51.1 -60.0  250  49 25   3.7   2.0
 45000 -45.0 -49.0  245  62 32   4.2   2.3 | -45.3 -49.5  240  62 32   3.9   2.1
 40000 -43.1 -45.6  240  63 33   1.1   0.6 | -43.6 -46.5  240  58 30   0.9   0.5
 38000 -42.8 -45.0  240  63 33  -3.4  -1.9 | -43.2 -45.8  235  55 28  -1.7  -0.9
 36000 -44.7 -48.5  240  59 30  -3.2  -1.8 | -44.3 -47.7  230  49 25  -1.7  -0.9
 34000 -46.6 -51.9  240  54 28  -3.2  -1.8 | -45.3 -49.5  225  42 22  -1.7  -0.9
 32000 -48.8 -55.8  235  43 22  -3.4  -1.9 | -46.6 -51.9  215  33 17  -2.7  -1.5
 30000 -50.9 -59.6  225  32 16  -3.2  -1.8 | -48.5 -55.3  190  23 12  -2.5  -1.4
 29000 -50.2 -58.4  215  29 15   6.9   3.8 | -48.3 -54.9  175  23 12   5.0   2.7
 28000 -48.0 -54.4  205  30 15   7.3   4.0 | -46.8 -52.2  165  27 14   5.0   2.8
 27000 -45.9 -50.6  195  31 16   7.2   4.0 | -45.3 -49.5  160  32 16   5.0   2.8
 26000 -43.6 -46.5  190  32 17   9.1   5.0 | -43.7 -46.7  155  36 19   7.2   4.0
 25000 -40.8 -41.4  190  30 16   9.4   5.2 | -41.1 -42.0  160  36 18   8.6   4.7
 24000 -38.0 -36.4  190  28 15   9.4   5.2 | -38.6 -37.5  160  35 18   8.6   4.7
 23000 -35.1 -31.2  190  26 14   9.7   5.3 | -36.0 -32.8  160  34 17   9.2   5.0
 22000 -32.2 -26.0  195  25 13   9.8   5.4 | -33.1 -27.6  165  32 17   9.6   5.3
 21000 -29.3 -20.7  200  23 12   9.8   5.4 | -30.2 -22.4  165  31 16   9.7   5.3
 20000 -26.6 -15.9  205  22 11   7.9   4.4 | -27.5 -17.5  170  29 15   7.7   4.2
 19500 -25.4 -13.7  205  22 11   8.1   4.4 | -26.3 -15.3  165  27 14   7.9   4.3
 19000 -24.2 -11.6  210  22 11   8.1   4.4 | -25.1 -13.2  165  25 13   8.0   4.4
 18500 -23.0  -9.4  215  22 12   8.1   4.4 | -23.9 -11.0  165  23 12   8.0   4.4
 18000 -21.8  -7.2  220  23 12   8.2   4.5 | -22.8  -9.0  160  21 11   8.0   4.4
 17500 -20.6  -5.1  220  23 12   7.5   4.1 | -21.6  -6.9  160  20 10   7.7   4.2
 17000 -19.5  -3.1  225  24 13   7.6   4.2 | -20.5  -4.9  165  18  9   7.7   4.2
 16500 -17.8  -0.0  225  26 14   7.3   4.0 | -19.4  -2.9  170  16  8   7.6   4.2
 16000 -16.7   1.9  225  28 14   7.3   4.0 | -17.7   0.1  180  16  8   7.6   4.1
 15500 -15.7   3.7  225  30 15   7.0   3.8 | -16.6   2.1  190  16  8   7.5   4.1
 15000 -14.7   5.5  225  31 16   6.9   3.8 | -15.5   4.1  195  17  9   7.4   4.1
 14500 -13.7   7.3  220  32 17   6.7   3.6 | -14.4   6.1  200  18  9   6.8   3.7
 14000 -12.8   9.0  215  32 16   6.5   3.6 | -13.5   7.7  200  19 10   5.8   3.2
 13500 -11.8  10.8  215  32 16   6.4   3.5 | -12.7   9.1  200  19 10   5.6   3.1
 13000 -10.9  12.4  210  31 16   6.1   3.4 | -11.9  10.6  195  20 10   5.0   2.8
 12500 -10.0  14.0  205  30 16   5.3   2.9 | -11.2  11.8  190  20 10   4.7   2.6
 12000  -9.5  14.9  200  30 15   2.6   1.4 | -10.9  12.4  185  21 11   0.1   0.1
 11500  -9.1  15.6  195  30 15   1.6   0.9 | -10.8  12.6  180  21 11   0.3   0.2
 11000  -9.2  15.4  185  29 15  -2.1  -1.1 | -11.0  12.2  175  22 11  -2.6  -1.4
 10500  -9.5  14.9  180  29 15  -1.8  -1.0 | -11.4  11.5  175  21 11  -1.6  -0.9
 10250  -9.6  14.7  180  29 15  -1.8  -1.0 | -11.4  11.5  175  21 11   1.8   1.0
 10000  -9.7  14.5  175  30 15  -1.0  -0.5 | -11.1  12.0  175  21 11   3.8   2.1
  9750  -9.8  14.4  170  30 15  -0.3  -0.1 | -10.8  12.6  170  22 11   3.8   2.1
  9500  -9.7  14.5  170  30 15   2.1   1.2 | -10.5  13.1  170  22 11   4.8   2.6
  9250  -9.5  14.9  165  29 15   4.4   2.4 | -10.1  13.8  165  22 11   6.2   3.4
  9000  -9.2  15.4  165  28 14   3.8   2.1 |  -9.7  14.5  160  22 11   6.2   3.4
  8750  -8.9  16.0  160  27 14   2.6   1.4 |  -9.3  15.3  160  21 11   4.4   2.4
  8500  -8.7  16.3  160  26 13   4.2   2.3 |  -8.9  16.0  155  20 10   6.0   3.3
  8250  -8.3  17.1  155  24 12   6.1   3.4 |  -8.4  16.9  150  18  9   8.4   4.6
  8000  -7.9  17.8  155  22 11   5.8   3.2 |  -7.8  18.0  150  17  9   7.9   4.3
  7750  -7.5  18.5  150  21 11   4.6   2.5 |  -7.2  19.0  145  16  8   6.4   3.5
  7500  -7.2  19.0  145  20 10   5.0   2.7 |  -6.8  19.8  140  15  8   6.3   3.4
  7250  -6.7  19.9  140  18  9   6.2   3.4 |  -6.3  20.7  135  14  7   7.5   4.1
  7000  -6.3  20.7  135  17  9   6.4   3.5 |  -5.8  21.6  130  13  6   7.2   4.0
  6750  -5.8  21.6  125  16  8   5.8   3.2 |  -5.2  22.6  120  12  6   7.9   4.3
  6500  -5.4  22.3  120  14  7   4.5   2.4 |  -4.6  23.7  110  11  5   8.2   4.5
  6250  -5.1  22.8  110  12  6   4.6   2.5 |  -4.0  24.8  105   9  5   8.4   4.6
  6000  -4.8  23.4  100  11  6   5.1   2.8 |  -3.5  25.7  090   9  4   7.4   4.0
  5750  -4.3  24.3  090   9  5   7.3   4.0 |  -2.9  26.8  085   8  4   8.9   4.9
  5500  -3.7  25.3  080   7  3   9.4   5.2 |  -2.1  28.2  080   7  3  14.4   7.9

           02/01/2016 at 1400 MST          |       02/01/2016 at 1700 MST
                                           |
K index... +14.4  LI... +6.9               | K index... +13.0  LI... +6.3
CAPE... +35.4  CIN... -0.9                 | CAPE... 0.0  CIN... -3.7
                                           |
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 -48.8 -55.8  240  54 28   3.0   1.7 | -48.7 -55.7  245  52 27   2.9   1.6
 45000 -44.0 -47.2  235  64 33   3.1   1.7 | -44.4 -47.9  245  60 31   2.9   1.6
 40000 -43.3 -45.9  235  53 27   0.2   0.1 | -43.4 -46.1  240  51 26   0.3   0.2
 38000 -43.2 -45.8  235  48 25  -1.0  -0.5 | -43.2 -45.8  240  46 24  -0.5  -0.3
 36000 -44.0 -47.2  230  41 21  -1.3  -0.7 | -43.7 -46.7  235  37 19  -0.8  -0.4
 34000 -44.8 -48.6  230  34 18  -1.3  -0.7 | -44.2 -47.6  235  28 14  -0.8  -0.4
 32000 -45.9 -50.6  220  26 13  -2.3  -1.3 | -45.4 -49.7  230  17  9  -3.1  -1.7
 30000 -47.5 -53.5  190  18  9  -2.3  -1.2 | -47.2 -53.0  190   5  3  -3.1  -1.7
 29000 -47.6 -53.7  175  17  9   3.9   2.1 | -47.8 -54.0  100   6  3   3.5   1.9
 28000 -46.5 -51.7  150  18  9   3.5   1.9 | -46.9 -52.4  070  10  5   2.9   1.6
 27000 -45.5 -49.9  135  21 11   3.5   1.9 | -46.0 -50.8  060  14  7   3.0   1.6
 26000 -44.4 -47.9  125  25 13   5.3   2.9 | -45.1 -49.2  055  19 10   4.7   2.6
 25000 -42.0 -43.6  125  25 13   8.5   4.7 | -42.6 -44.7  060  17  9   9.0   4.9
 24000 -39.4 -38.9  130  25 13   8.5   4.7 | -39.9 -39.8  065  14  7   9.0   4.9
 23000 -36.8 -34.2  135  24 12   8.7   4.8 | -37.3 -35.1  080  12  6   9.0   5.0
 22000 -34.2 -29.6  140  23 12   9.0   4.9 | -34.5 -30.1  090  10  5   9.2   5.1
 21000 -31.5 -24.7  145  21 11   9.0   4.9 | -31.8 -25.2  100   8  4   9.3   5.1
 20000 -28.8 -19.8  155  20 10   9.1   5.0 | -29.1 -20.4  115   8  4   7.8   4.3
 19500 -27.4 -17.3  150  19 10   9.1   5.0 | -28.0 -18.4  120   8  4   7.5   4.1
 19000 -26.1 -15.0  150  18  9   9.1   5.0 | -26.9 -16.4  125   8  4   7.5   4.1
 18500 -24.8 -12.6  150  16  8   9.1   5.0 | -25.7 -14.3  130   8  4   7.5   4.1
 18000 -23.4 -10.1  150  15  8   9.1   5.0 | -24.6 -12.3  135   8  4   7.5   4.1
 17500 -22.1  -7.8  150  14  7   8.4   4.6 | -23.6 -10.5  140   8  4   6.3   3.5
 17000 -20.9  -5.6  150  12  6   8.1   4.5 | -22.7  -8.9  140   8  4   5.9   3.2
 16500 -19.7  -3.5  155  11  6   7.9   4.4 | -21.8  -7.2  140   7  4   5.6   3.0
 16000 -18.1  -0.6  165  11  6   7.3   4.0 | -21.1  -6.0  140   5  3   4.4   2.4
 15500 -17.0   1.4  170  12  6   6.9   3.8 | -20.1  -4.2  130   3  2   3.2   1.8
 15000 -16.1   3.0  170  12  6   6.5   3.6 | -19.9  -3.8  075   1  1   1.9   1.0
 14500 -15.1   4.8  175  12  6   6.1   3.3 | -19.6  -3.3  010   3  1   1.9   1.1
 14000 -14.4   6.1  175  13  7   4.0   2.2 | -19.2  -2.6  355   4  2   2.5   1.4
 13500 -13.8   7.2  175  14  7   4.2   2.3 | -18.9  -2.0  350   5  3   2.8   1.5
 13000 -13.6   7.5  175  13  7  -1.1  -0.6 | -18.0  -0.4  340   4  2   8.1   4.4
 12500 -13.7   7.3  180  11  6  -0.5  -0.3 | -16.9   1.6  320   2  1   7.7   4.2
 12000 -13.8   7.2  185   9  5  -2.1  -1.2 | -15.7   3.7  185   2  1   9.1   5.0
 11500 -14.1   6.6  190   8  4  -2.7  -1.5 | -14.3   6.3  165   7  4   8.9   4.9
 11000 -13.6   7.5  190   9  4   9.0   4.9 | -13.3   8.1  150  12  6   5.9   3.2
 10500 -12.5   9.5  180  11  6   7.9   4.3 | -12.4   9.7  140  17  9   6.2   3.4
 10250 -11.9  10.6  175  13  7   9.1   5.0 | -11.9  10.6  140  18  9   6.6   3.6
 10000 -11.2  11.8  170  15  8   7.6   4.2 | -11.4  11.5  130  18  9   6.4   3.5
  9750 -10.8  12.6  160  17  9   4.4   2.4 | -11.0  12.2  130  18  9   5.4   3.0
  9500 -10.5  13.1  155  18  9   4.9   2.7 | -10.6  12.9  125  18  9   6.3   3.5
  9250 -10.0  14.0  150  18  9   6.2   3.4 | -10.1  13.8  120  19 10   7.9   4.3
  9000  -9.6  14.7  145  18  9   6.7   3.7 |  -9.5  14.9  120  20 10   7.9   4.3
  8750  -9.1  15.6  140  18  9   6.2   3.4 |  -9.0  15.8  115  21 11   6.5   3.5
  8500  -8.6  16.5  135  17  9   7.2   3.9 |  -8.5  16.7  115  22 11   6.3   3.5
  8250  -8.0  17.6  130  17  9   8.2   4.5 |  -8.0  17.6  110  22 12   7.0   3.8
  8000  -7.5  18.5  125  17  9   8.2   4.5 |  -7.5  18.5  105  23 12   7.2   4.0
  7750  -6.9  19.6  120  17  9   5.9   3.2 |  -7.0  19.4  100  25 13   5.0   2.8
  7500  -6.5  20.3  115  18  9   6.3   3.5 |  -6.8  19.8  095  25 13   2.7   1.5
  7250  -6.0  21.2  105  17  9   8.5   4.7 |  -6.6  20.1  085  26 13   3.0   1.7
  7000  -5.4  22.3  100  17  9   7.9   4.3 |  -6.3  20.7  080  26 13   3.3   1.8
  6750  -4.8  23.4  095  18  9   8.1   4.4 |  -6.0  21.2  075  26 13   5.4   3.0
  6500  -4.2  24.4  090  17  9   8.2   4.5 |  -5.6  21.9  070  24 12   6.5   3.6
  6250  -3.6  25.5  085  16  8   8.7   4.8 |  -5.1  22.8  065  22 11   5.7   3.1
  6000  -3.0  26.6  080  15  8   7.5   4.1 |  -4.7  23.5  060  20 10   7.2   3.9
  5750  -2.4  27.7  075  14  7   8.8   4.8 |  -4.1  24.6  060  18  9   9.4   5.1
  5500  -1.6  29.1  070  12  6  14.1   7.7 |  -3.4  25.9  055  15  8   9.2   5.0
________________________________________________________________________________

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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