Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 310022
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1722 MST Saturday, January 30, 2016

This forecast is for Sunday, January 31, 2016:

If the trigger temperature of 39.4 F/4.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8007 ft MSL (2700 ft AGL)

Forecast maximum temperature................... 36.0 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................. 6259 ft MSL (952 ft AGL)
Thermal soaring outlook for Monday 02/01....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Getting worse
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 23494 ft MSL (18187 ft AGL)
Wave soaring outlook for Monday 02/01.......... Poor

Remarks...

Sunrise/Sunset.................... 07:08:32 / 17:16:14 MST
Total possible sunshine........... 10 hr 7 min 42 sec (607 min 42 sec)
Altitude of sun at 12:12:46 MST... 32.91 degrees

Upper air data from numerical model forecast valid on 01/31/2016 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 10096 ft MSL (4789 ft AGL)
Lifted condensation level....... 8916 ft MSL (3610 ft AGL)
Lifted index.................... +11.3
K index......................... +5.0

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  -55.0 -67.0   270   51   26   5.0   2.8      M     M       M      M    M
 45000  -47.5 -53.5   280   71   36   4.9   2.7      M     M       M      M    M
 40000  -43.6 -46.5   280   74   38   2.4   1.3      M     M       M      M    M
 38000  -42.7 -44.9   280   77   39  -0.4  -0.2      M     M       M      M    M
 36000  -43.0 -45.4   285   82   42  -0.5  -0.3      M     M       M      M    M
 34000  -43.2 -45.8   285   88   46  -0.4  -0.2      M     M       M      M    M
 32000  -44.4 -47.9   280   89   46  -2.3  -1.3      M     M       M      M    M
 30000  -46.0 -50.8   270   89   46  -2.2  -1.2      M     M       M      M    M
 29000  -44.8 -48.6   270   89   46   5.5   3.0   28.7  83.7    20.0      M    M
 28000  -43.2 -45.8   270   89   46   5.5   3.0   26.9  80.5    18.9      M    M
 27000  -41.6 -42.9   270   89   46   5.5   3.0   25.4  77.6    17.9      M    M
 26000  -39.5 -39.1   270   89   46   9.1   5.0   24.3  75.7    17.3      M    M
 25000  -36.9 -34.4   270   92   47   8.9   4.9   23.9  75.0    17.2      M    M
 24000  -34.2 -29.6   275   94   48   8.9   4.9   23.6  74.5    17.2      M    M
 23000  -31.7 -25.1   275   95   49   6.7   3.7   23.1  73.7    17.0      M    M
 22000  -29.6 -21.3   275   93   48   7.0   3.8   22.0  71.7    16.3      M    M
 21000  -27.6 -17.7   275   90   46   6.9   3.8   21.1  70.0    15.7      M    M
 20000  -25.9 -14.6   275   84   43   4.1   2.3   19.6  67.3    14.6      M    M
 19500  -25.3 -13.5   275   79   41   4.1   2.2   18.6  65.5    13.8      M    M
 19000  -24.7 -12.5   270   75   39   4.1   2.2   17.6  63.7    13.0      M    M
 18500  -24.1 -11.4   265   70   36   4.2   2.3   16.6  61.9    12.3      M    M
 18000  -23.4 -10.1   265   66   34   5.3   2.9   15.7  60.3    11.6      M    M
 17500  -22.3  -8.1   260   64   33   8.2   4.5   15.3  59.5    11.3      M    M
 17000  -21.1  -6.0   260   62   32   8.3   4.5   15.0  59.0    11.1      M    M
 16500  -20.0  -4.0   260   60   31   7.0   3.8   14.7  58.4    10.8      M    M
 16000  -18.9  -2.0   265   58   30   7.1   3.9   14.2  57.6    10.5      M    M
 15500  -17.6   0.3   265   54   28   4.6   2.5   13.3  55.9     9.7      M    M
 15000  -16.9   1.6   265   51   26   4.8   2.7   12.5  54.4     9.0      M    M
 14500  -16.2   2.8   270   47   24   4.3   2.4   11.6  52.9     8.3      M    M
 14000  -15.6   3.9   265   42   21   4.3   2.3   10.7  51.3     7.5      M    M
 13500  -14.9   5.2   265   36   19   5.3   2.9    9.9  49.8     6.8      M    M
 13000  -14.1   6.6   260   30   16   5.4   3.0    9.2  48.5     6.1      M    M
 12500  -13.2   8.2   260   26   13   7.6   4.1    8.6  47.4     5.6      M    M
 12000  -12.0  10.4   265   24   12   8.3   4.5    8.3  47.0     5.4      M    M
 11500  -10.9  12.4   270   22   12   4.7   2.6    7.9  46.3     5.0      M    M
 11000  -10.4  13.3   280   20   10   3.6   2.0    6.9  44.5     4.1      M    M
 10500   -9.7  14.5   290   18    9   5.3   2.9    6.1  42.9     3.3      M    M
 10250   -9.3  15.3   295   18    9   6.3   3.5    5.7  42.3     3.0      M    M
 10000   -8.9  16.0   300   18    9   3.9   2.1    5.4  41.8     2.8      M    M
  9750   -8.7  16.3   305   17    9   4.0   2.2    4.9  40.8     2.2      M    M
  9500   -8.2  17.2   305   16    8   7.2   4.0    4.6  40.3     2.0      M    M
  9250   -7.7  18.1   310   15    8   7.9   4.3    4.4  40.0     1.8      M    M
  9000   -7.1  19.2   310   14    7   6.0   3.3    4.3  39.7     1.6      M    M
  8750   -6.8  19.8   315   13    7   4.2   2.3    3.9  38.9     1.2      M    M
  8500   -6.5  20.3   315   12    6   4.9   2.7    3.5  38.2     0.8      M    M
  8250   -6.2  20.8   315   10    5   4.4   2.4    3.1  37.5     0.4      M    M
  8000   -5.8  21.6   315    9    4   5.8   3.2    2.7  36.8     0.0      M    M
  7750   -5.4  22.3   320    7    3   5.7   3.1    2.4  36.3    -0.3    160  0.8
  7500   -5.1  22.8   325    6    3   4.4   2.4    2.0  35.6    -0.7    142  0.7
  7250   -4.7  23.5   330    5    3   4.8   2.6    1.6  34.9    -1.1    125  0.6
  7000   -4.4  24.1   340    4    2   4.2   2.3    1.2  34.2    -1.5    108  0.5
  6750   -4.1  24.6   355    3    1   3.6   2.0    0.8  33.4    -2.0     93  0.5
  6500   -3.9  25.0   020    2    1   2.7   1.5    0.3  32.5    -2.5     78  0.4
  6250   -3.7  25.3   065    2    1   5.1   2.8   -0.2  31.6    -3.0     64  0.3
  6000   -3.2  26.2   060    2    1   8.1   4.5   -0.4  31.3    -3.2     41  0.2
  5750   -2.6  27.3   055    3    1   8.3   4.6   -0.5  31.1    -3.3     16  0.1
  5500   -1.9  28.6   050    3    1   9.0   4.9   -0.6  30.9    -3.5      M    M

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

           01/31/2016 at 0800 MST          |       01/31/2016 at 1100 MST
                                           |
K index... +3.2  LI... +7.3                | K index... +4.0  LI... +8.8
CAPE... 0.0  CIN... -1.1                   | 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 -54.0 -65.2  275  50 26   4.5   2.4 | -53.0 -63.4  265  51 26   4.2   2.3
 45000 -47.3 -53.1  280  74 38   4.4   2.4 | -46.4 -51.5  275  75 39   3.0   1.7
 40000 -43.9 -47.0  280  74 38   2.1   1.2 | -42.9 -45.2  275  84 43   2.3   1.3
 38000 -43.1 -45.6  280  76 39  -0.6  -0.3 | -42.2 -44.0  275  87 45  -1.5  -0.8
 36000 -43.5 -46.3  280  80 41  -0.6  -0.3 | -43.1 -45.6  275  87 45  -1.6  -0.9
 34000 -43.9 -47.0  280  85 44  -0.6  -0.3 | -44.1 -47.4  275  87 45  -1.5  -0.8
 32000 -44.8 -48.6  275  87 45  -1.7  -0.9 | -45.1 -49.2  270  85 44  -1.8  -1.0
 30000 -46.0 -50.8  275  88 45  -1.5  -0.8 | -46.3 -51.3  265  82 42  -1.6  -0.9
 29000 -44.9 -48.8  275  88 45   4.8   2.6 | -45.3 -49.5  265  79 41   4.6   2.5
 28000 -43.5 -46.3  270  87 45   4.8   2.6 | -44.0 -47.2  265  77 40   4.6   2.5
 27000 -42.1 -43.8  270  87 45   4.8   2.6 | -42.6 -44.7  265  74 38   4.7   2.6
 26000 -40.2 -40.4  270  86 45   8.8   4.8 | -40.8 -41.4  265  72 37   8.9   4.9
 25000 -37.6 -35.7  270  85 44   8.6   4.7 | -38.2 -36.8  265  69 36   8.7   4.8
 24000 -35.1 -31.2  275  84 43   8.6   4.7 | -35.6 -32.1  270  67 34   8.7   4.8
 23000 -32.4 -26.3  275  83 43   9.6   5.3 | -32.9 -27.2  270  65 33   9.3   5.1
 22000 -29.6 -21.3  280  79 41   9.5   5.2 | -30.1 -22.2  270  64 33   9.2   5.1
 21000 -26.7 -16.1  280  75 39   9.3   5.1 | -27.4 -17.3  270  63 33   9.2   5.0
 20000 -24.6 -12.3  280  73 38   5.2   2.9 | -25.0 -13.0  275  63 32   6.9   3.8
 19500 -23.8 -10.8  280  72 37   5.1   2.8 | -24.0 -11.2  275  63 32   6.8   3.7
 19000 -23.1  -9.6  275  72 37   5.1   2.8 | -23.0  -9.4  275  63 32   6.8   3.7
 18500 -22.3  -8.1  275  71 37   5.1   2.8 | -22.0  -7.6  275  63 33   6.8   3.7
 18000 -21.5  -6.7  275  70 36   4.9   2.7 | -21.0  -5.8  275  63 33   6.1   3.3
 17500 -20.9  -5.6  275  68 35   4.6   2.5 | -20.2  -4.4  275  61 31   4.8   2.6
 17000 -20.2  -4.4  275  65 34   4.6   2.5 | -19.5  -3.1  275  58 30   4.8   2.6
 16500 -19.5  -3.1  270  63 33   4.7   2.6 | -18.8  -1.8  270  56 29   4.2   2.3
 16000 -18.8  -1.8  270  62 32   4.7   2.6 | -17.9  -0.2  270  55 28   4.3   2.4
 15500 -17.8  -0.0  270  60 31   4.6   2.5 | -17.2   1.0  270  53 27   4.2   2.3
 15000 -17.1   1.2  270  58 30   4.6   2.5 | -16.6   2.1  270  51 26   4.3   2.4
 14500 -16.4   2.5  270  55 29   4.8   2.6 | -16.0   3.2  270  48 25   3.5   1.9
 14000 -15.7   3.7  270  51 26   4.9   2.7 | -15.5   4.1  270  45 23   3.5   1.9
 13500 -15.0   5.0  270  46 24   3.7   2.0 | -15.0   5.0  270  42 22   3.2   1.7
 13000 -14.5   5.9  270  40 21   3.3   1.8 | -14.5   5.9  270  38 20   3.1   1.7
 12500 -13.9   7.0  265  34 18   5.9   3.2 | -14.0   6.8  270  34 17   4.7   2.6
 12000 -13.0   8.6  265  29 15   6.7   3.7 | -13.3   8.1  270  29 15   5.0   2.7
 11500 -12.0  10.4  260  24 12   6.0   3.3 | -12.5   9.5  265  24 12   6.4   3.5
 11000 -11.2  11.8  265  20 10   5.9   3.2 | -11.5  11.3  265  20 10   6.8   3.7
 10500 -10.4  13.3  270  17  9   5.1   2.8 | -10.6  12.9  265  16  8   5.6   3.1
 10250 -10.0  14.0  275  16  8   4.4   2.4 | -10.2  13.6  265  14  7   5.1   2.8
 10000  -9.6  14.7  280  15  8   6.2   3.4 |  -9.8  14.4  260  13  6   6.6   3.6
  9750  -9.1  15.6  290  15  8   6.5   3.6 |  -9.2  15.4  260  11  6   7.2   4.0
  9500  -8.7  16.3  295  14  7   4.5   2.5 |  -8.8  16.2  265  10  5   5.7   3.1
  9250  -8.4  16.9  300  14  7   3.9   2.1 |  -8.3  17.1  265   8  4   6.0   3.3
  9000  -8.0  17.6  305  14  7   5.7   3.1 |  -7.9  17.8  265   7  4   5.2   2.8
  8750  -7.5  18.5  315  14  7   6.1   3.3 |  -7.6  18.3  275   6  3   5.0   2.7
  8500  -7.2  19.0  315  13  7   4.7   2.6 |  -7.1  19.2  285   6  3   5.6   3.1
  8250  -6.8  19.8  320  12  6   4.7   2.6 |  -6.7  19.9  295   5  3   5.5   3.0
  8000  -6.5  20.3  325  11  6   6.3   3.5 |  -6.3  20.7  310   5  2   5.4   3.0
  7750  -6.0  21.2  330   9  5   6.3   3.5 |  -5.9  21.4  330   4  2   5.0   2.8
  7500  -5.6  21.9  335   8  4   4.6   2.5 |  -5.5  22.1  345   4  2   4.9   2.7
  7250  -5.3  22.5  335   7  4   4.9   2.7 |  -5.2  22.6  005   3  2   5.0   2.7
  7000  -4.9  23.2  340   6  3   5.8   3.2 |  -4.8  23.4  025   3  2   7.4   4.0
  6750  -4.6  23.7  340   5  2   4.0   2.2 |  -4.2  24.4  050   3  2   6.7   3.7
  6500  -4.4  24.1  345   3  2   1.0   0.6 |  -3.9  25.0  075   3  2   3.8   2.1
  6250  -4.3  24.3  345   2  1   2.7   1.5 |  -3.6  25.5  095   3  2   5.9   3.3
  6000  -4.1  24.6  345   1  1   3.8   2.1 |  -3.1  26.4  110   3  2   7.6   4.2
  5750  -3.8  25.2  000   0  0   4.4   2.4 |  -2.6  27.3  125   3  2   7.4   4.1
  5500  -3.3  26.1  000   0  0   9.4   5.2 |  -1.9  28.6  135   3  1  13.2   7.3

           01/31/2016 at 1400 MST          |       01/31/2016 at 1700 MST
                                           |
K index... +13.0  LI... +6.7               | K index... +11.9  LI... +5.6
CAPE... 0.0  CIN... -0.4                   | 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 -53.4 -64.1  260  53 27   4.1   2.2 | -53.4 -64.1  255  66 34   3.8   2.1
 45000 -47.3 -53.1  265  81 42   4.1   2.2 | -47.8 -54.0  260  81 42   3.8   2.1
 40000 -43.2 -45.8  270  87 45   2.6   1.4 | -42.1 -43.8  260  80 41   3.6   2.0
 38000 -42.3 -44.1  270  88 45  -0.8  -0.4 | -40.8 -41.4  265  80 41  -0.9  -0.5
 36000 -42.8 -45.0  270  85 44  -0.8  -0.4 | -41.4 -42.5  265  80 41  -1.0  -0.6
 34000 -43.2 -45.8  265  83 43  -0.8  -0.4 | -42.0 -43.6  265  80 41  -1.1  -0.6
 32000 -44.3 -47.7  265  81 42  -2.0  -1.1 | -44.9 -48.8  265  77 40  -6.0  -3.3
 30000 -45.5 -49.9  270  79 41  -1.9  -1.1 | -48.5 -55.3  265  73 38  -5.6  -3.0
 29000 -45.2 -49.4  265  77 40   2.6   1.5 | -47.9 -54.2  265  71 37   6.9   3.8
 28000 -44.4 -47.9  265  75 39   2.6   1.4 | -45.9 -50.6  265  70 36   6.8   3.8
 27000 -43.6 -46.5  265  74 38   2.7   1.5 | -43.8 -46.8  260  68 35   6.9   3.8
 26000 -42.1 -43.8  265  72 37  10.3   5.6 | -41.5 -42.7  260  67 35   9.5   5.2
 25000 -39.2 -38.6  265  69 36   9.8   5.4 | -38.8 -37.8  255  67 34   9.3   5.1
 24000 -36.2 -33.2  265  67 34   9.8   5.4 | -36.0 -32.8  255  66 34   9.3   5.1
 23000 -33.4 -28.1  265  64 33   8.7   4.8 | -33.3 -27.9  255  66 34   7.5   4.1
 22000 -30.8 -23.4  265  59 30   8.9   4.9 | -31.0 -23.8  250  63 32   7.7   4.2
 21000 -28.1 -18.6  265  54 28   8.8   4.8 | -28.7 -19.7  250  61 31   7.7   4.2
 20000 -25.8 -14.4  265  53 27   7.0   3.9 | -26.6 -15.9  250  57 29   6.1   3.4
 19500 -24.7 -12.5  265  54 28   7.0   3.8 | -25.7 -14.3  255  54 28   6.1   3.4
 19000 -23.7 -10.7  265  55 28   7.0   3.8 | -24.8 -12.6  255  51 26   6.1   3.4
 18500 -22.6  -8.7  270  56 29   7.0   3.8 | -23.9 -11.0  260  48 25   6.1   3.4
 18000 -21.6  -6.9  270  57 29   6.5   3.5 | -23.0  -9.4  260  46 24   6.0   3.3
 17500 -20.8  -5.4  270  58 30   5.3   2.9 | -22.2  -8.0  265  44 23   5.6   3.1
 17000 -20.0  -4.0  270  59 30   5.4   3.0 | -21.3  -6.3  265  43 22   5.6   3.1
 16500 -19.3  -2.7  270  58 30   3.8   2.1 | -20.5  -4.9  265  40 21   5.8   3.2
 16000 -18.8  -1.8  265  55 28   3.9   2.1 | -19.6  -3.3  265  36 19   5.8   3.2
 15500 -18.0  -0.4  265  50 26   3.2   1.7 | -18.8  -1.8  265  32 17   5.4   3.0
 15000 -17.5   0.5  265  47 24   3.2   1.7 | -17.7   0.1  260  23 12   5.2   2.9
 14500 -17.0   1.4  265  42 22   4.2   2.3 | -16.9   1.6  250  18  9   5.1   2.8
 14000 -16.3   2.7  265  36 18   4.1   2.2 | -16.1   3.0  245  15  8   5.1   2.8
 13500 -15.7   3.7  265  30 15   5.1   2.8 | -15.3   4.5  235  12  6   6.4   3.5
 13000 -14.9   5.2  260  24 13   5.2   2.9 | -14.4   6.1  220  10  5   6.7   3.7
 12500 -14.2   6.4  260  19 10   5.7   3.1 | -13.4   7.9  205  10  5   5.0   2.8
 12000 -13.3   8.1  255  16  8   5.9   3.2 | -12.8   9.0  195  12  6   4.5   2.5
 11500 -12.4   9.7  250  13  7   6.4   3.5 | -12.1  10.2  190  14  7   4.1   2.3
 11000 -11.5  11.3  240  11  5   6.5   3.5 | -11.5  11.3  185  14  7   4.0   2.2
 10500 -10.5  13.1  225   9  5   7.1   3.9 | -10.9  12.4  175  13  7   4.4   2.4
 10250 -10.0  14.0  220   8  4   7.0   3.9 | -10.6  12.9  165  12  6   4.3   2.4
 10000  -9.4  15.1  215   8  4   7.7   4.2 | -10.3  13.5  160  11  6   4.8   2.6
  9750  -8.9  16.0  205   7  4   6.4   3.5 |  -9.9  14.2  150  11  6   5.0   2.7
  9500  -8.5  16.7  200   7  3   4.3   2.3 |  -9.6  14.7  140  10  5   4.4   2.4
  9250  -8.2  17.2  195   6  3   4.5   2.4 |  -9.2  15.4  130  10  5   4.6   2.5
  9000  -7.8  18.0  185   6  3   4.1   2.3 |  -8.9  16.0  120   9  5   4.0   2.2
  8750  -7.5  18.5  175   5  3   4.2   2.3 |  -8.6  16.5  110   9  5   4.4   2.4
  8500  -7.2  19.0  160   4  2   4.8   2.6 |  -8.3  17.1  105  10  5   5.5   3.0
  8250  -6.8  19.8  135   4  2   3.8   2.1 |  -7.9  17.8  105  11  6   4.8   2.7
  8000  -6.5  20.3  110   4  2   7.2   4.0 |  -7.5  18.5  100  11  6   6.5   3.6
  7750  -5.8  21.6  095   6  3   9.9   5.4 |  -6.9  19.6  100  13  6   7.3   4.0
  7500  -5.2  22.6  090   6  3   8.4   4.6 |  -6.5  20.3  100  13  7   6.4   3.5
  7250  -4.5  23.9  090   7  4   8.8   4.8 |  -6.0  21.2  100  13  7   6.6   3.6
  7000  -3.8  25.2  085   7  4  10.2   5.6 |  -5.4  22.3  100  13  7   9.2   5.0
  6750  -3.0  26.6  090   7  4  10.3   5.7 |  -4.7  23.5  105  13  7   9.8   5.4
  6500  -2.3  27.9  090   7  4   9.1   5.0 |  -4.1  24.6  105  13  6   7.6   4.2
  6250  -1.6  29.1  090   7  4   9.9   5.4 |  -3.5  25.7  105  12  6   9.1   5.0
  6000  -0.9  30.4  090   7  4  10.6   5.8 |  -2.8  27.0  100  11  6  10.7   5.9
  5750  -0.1  31.8  085   7  4  10.0   5.5 |  -2.0  28.4  100  10  5   9.6   5.3
  5500   0.7  33.3  085   7  3  13.2   7.2 |  -1.3  29.7  100   9  4   9.6   5.3
________________________________________________________________________________

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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