Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 281210
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0510 MST Sunday, December 28, 2014

This forecast is for Sunday, December 28, 2014:

If the trigger temperature of 40.9 F/4.9 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6713 ft MSL (1428 ft AGL)

Forecast maximum temperature................... 35.0 F/2.1 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 1400 MST
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6008 ft MSL (722 ft AGL)
Thermal soaring outlook for Monday 12/29....... Poor

Wave Soaring Index............................. Excellent
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 15876 ft MSL (10591 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 16369 ft MSL (11084 ft AGL)
Wave soaring outlook for Monday 12/29.......... Good

Remarks... None

Sunrise/Sunset.................... 07:19:43 / 16:42:40 MST
Total possible sunshine........... 9 hr 22 min 56 sec (562 min 56 sec)
Altitude of sun at 12:01:09 MST... 27.05 degrees

Upper air data from rawinsonde observation taken on 12/28/2014 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 19480 ft MSL (14195 ft AGL)
Lifted condensation level....... 13821 ft MSL (8536 ft AGL)
Lifted index.................... +13.3
K index......................... +3.4

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  -58.1 -72.6   270   36   19   3.1   1.7  106.5 223.8    59.4      M    M
 45000  -59.1 -74.4   275   47   24   1.4   0.8   78.8 173.9    46.9      M    M
 40000  -53.7 -64.7   285   42   22   1.3   0.7   64.3 147.7    40.7      M    M
 38000  -50.8 -59.4   295   53   27   1.6   0.9   59.8 139.6    38.8      M    M
 36000  -55.5 -67.9   305   71   37   1.1   0.6   44.2 111.6    29.2      M    M
 34000  -55.1 -67.2   305   76   39   5.7   3.1   36.3  97.3    24.4      M    M
 32000  -51.1 -60.0   300   67   35   6.0   3.3   32.6  90.7    22.5      M    M
 30000  -50.0 -58.0   295   62   32   3.8   2.1   26.3  79.3    18.3      M    M
 29000  -48.0 -54.4   295   58   30   6.9   3.8   25.0  76.9    17.6      M    M
 28000  -45.9 -50.6   290   55   28   6.8   3.8   23.9  75.0    17.0      M    M
 27000  -43.7 -46.7   290   52   27   9.2   5.0   23.0  73.4    16.5      M    M
 26000  -42.2 -44.0   290   49   25  10.6   5.8   21.1  70.0    15.2      M    M
 25000  -39.3 -38.7   285   46   24   9.7   5.3   21.1  70.0    15.4      M    M
 24000  -36.6 -33.9   285   44   23   8.1   4.4   20.8  69.5    15.4      M    M
 23000  -34.5 -30.1   285   41   21   6.3   3.5   19.9  67.7    14.8      M    M
 22000  -32.2 -26.0   280   35   18   8.0   4.4   19.1  66.3    14.3      M    M
 21000  -30.0 -22.0   285   35   18   7.0   3.8   18.2  64.8    13.7      M    M
 20000  -27.7 -17.9   295   36   18   8.3   4.6   17.5  63.6    13.3      M    M
 19500  -26.4 -15.5   295   36   19   8.4   4.6   17.2  63.0    13.1      M    M
 19000  -25.2 -13.4   295   36   19   8.4   4.6   17.0  62.6    13.0      M    M
 18500  -23.9 -11.0   295   36   19   8.4   4.6   16.8  62.2    12.9      M    M
 18000  -22.7  -8.9   295   36   18   8.4   4.6   16.5  61.8    12.7      M    M
 17500  -21.4  -6.5   295   35   18   8.4   4.6   16.3  61.3    12.6      M    M
 17000  -20.2  -4.4   300   35   18   8.4   4.6   16.1  61.0    12.5      M    M
 16500  -18.9  -2.0   300   37   19   8.7   4.8   15.9  60.5    12.3      M    M
 16000  -18.0  -0.4   300   39   20   1.0   0.6   15.3  59.6    11.9      M    M
 15500  -18.0  -0.4   300   40   21   4.7   2.6   12.8  55.1     9.8      M    M
 15000  -17.3   0.9   295   40   21   4.4   2.4   12.0  53.5     9.0      M    M
 14500  -16.5   2.3   295   40   21   7.2   4.0   11.3  52.3     8.5      M    M
 14000  -15.4   4.3   295   40   21   7.2   4.0   10.9  51.6     8.2      M    M
 13500  -14.3   6.3   295   41   21   7.2   4.0   10.5  50.9     7.8      M    M
 13000  -13.2   8.2   295   41   21   7.2   4.0   10.1  50.2     7.5      M    M
 12500  -12.1  10.2   300   38   19   7.2   4.0    9.7  49.4     7.2      M    M
 12000  -11.1  12.0   300   35   18   7.2   4.0    9.3  48.7     6.9      M    M
 11500  -10.0  14.0   300   32   16   7.2   4.0    8.9  47.9     6.5      M    M
 11000   -8.9  16.0   300   29   15   6.9   3.8    8.4  47.2     6.2      M    M
 10500   -8.4  16.9   305   27   14  -0.0  -0.0    7.3  45.2     5.2      M    M
 10250   -8.4  16.9   305   25   13   0.5   0.3    6.6  43.9     4.5      M    M
 10000   -8.3  17.1   305   24   12   0.9   0.5    5.9  42.6     3.8      M    M
  9750   -8.1  17.4   305   22   11   5.0   2.8    5.3  41.6     3.3      M    M
  9500   -7.6  18.3   305   20   10   8.7   4.7    5.1  41.2     3.2      M    M
  9250   -6.9  19.6   310   17    9   8.9   4.9    5.1  41.1     3.1      M    M
  9000   -6.2  20.8   310   15    8   8.8   4.9    5.0  41.0     3.1      M    M
  8750   -5.6  21.9   300   10    5   8.7   4.8    4.9  40.9     3.0      M    M
  8500   -4.9  23.2   275    6    3   9.2   5.1    4.9  40.7     2.9      M    M
  8250   -4.3  24.3   220    5    3   7.3   4.0    4.8  40.6     2.9      M    M
  8000   -3.9  25.0   185    8    4   0.4   0.2    4.4  39.9     2.5      M    M
  7750   -4.0  24.8   180    9    4  -0.7  -0.4    3.5  38.3     1.6      M    M
  7500   -3.9  25.0   175    9    5   4.5   2.5    2.9  37.2     1.1      M    M
  7250   -3.5  25.7   170   10    5   5.7   3.1    2.6  36.7     0.8      M    M
  7000   -3.0  26.6   165   11    6   6.2   3.4    2.3  36.1     0.5      M    M
  6750   -2.6  27.3   170   11    6   3.0   1.7    2.0  35.6     0.1      M    M
  6500   -2.6  27.3   175   11    6  -0.8  -0.4    1.2  34.2    -0.6     62  0.3
  6250   -2.8  27.0   185   11    6  -5.6  -3.1    0.3  32.6    -1.5     60  0.3
  6000   -3.5  25.7   190   11    6  -9.7  -5.3   -1.1  30.1    -2.9     72  0.4
  5750   -4.6  23.7   190    8    4 -26.3 -14.4   -2.9  26.8    -4.7     99  0.5
  5500   -7.8  18.0   190    4    2 -55.6 -30.5   -6.8  19.7    -8.7    187  0.9

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

           12/28/2014 at 0800 MST          |       12/28/2014 at 1100 MST
                                           |
K index... +8.4  LI... +4.7                | K index... +6.3  LI... +4.2
CAPE... 0.0  CIN... -1.0                   | CAPE... 0.0  CIN... -0.3
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -55.4 -67.7  265  34 17   1.7   0.9 | -54.5 -66.1  265  38 19   1.7   0.9
 45000 -52.7 -62.9  275  37 19   1.6   0.9 | -51.8 -61.2  280  44 23   1.7   0.9
 40000 -52.7 -62.9  280  62 32  -0.2  -0.1 | -52.7 -62.9  280  64 33  -1.0  -0.5
 38000 -52.8 -63.0  280  72 37   0.2   0.1 | -53.3 -63.9  280  72 37  -0.7  -0.4
 36000 -52.7 -62.9  285  76 39   0.2   0.1 | -53.6 -64.5  280  74 38  -0.6  -0.3
 34000 -52.6 -62.7  290  80 41   0.2   0.1 | -54.0 -65.2  285  77 39  -0.6  -0.3
 32000 -50.8 -59.4  290  79 40   3.4   1.8 | -52.3 -62.1  285  76 39   4.6   2.5
 30000 -48.8 -55.8  290  75 39   3.2   1.7 | -49.2 -56.6  280  74 38   4.5   2.5
 29000 -47.5 -53.5  290  72 37   5.0   2.7 | -47.7 -53.9  280  71 36   5.2   2.8
 28000 -46.0 -50.8  285  67 34   5.0   2.7 | -46.1 -51.0  280  67 34   5.2   2.8
 27000 -44.5 -48.1  280  63 32   5.0   2.7 | -44.6 -48.3  280  62 32   5.2   2.8
 26000 -42.8 -45.0  280  58 30   7.7   4.2 | -43.0 -45.4  280  58 30   5.9   3.3
 25000 -40.5 -40.9  275  54 28   7.4   4.1 | -41.2 -42.2  275  53 27   5.8   3.2
 24000 -38.3 -36.9  275  50 26   7.5   4.1 | -39.5 -39.1  275  48 25   5.8   3.2
 23000 -36.0 -32.8  270  45 23   8.6   4.7 | -37.5 -35.5  270  44 23   8.8   4.8
 22000 -33.5 -28.3  270  39 20   8.5   4.7 | -35.0 -31.0  265  42 21   8.6   4.7
 21000 -30.9 -23.6  275  33 17   8.5   4.7 | -32.4 -26.3  265  39 20   8.5   4.7
 20000 -28.6 -19.5  275  30 16   7.3   4.0 | -30.0 -22.0  265  36 19   7.8   4.3
 19500 -27.5 -17.5  280  30 15   7.2   4.0 | -28.8 -19.8  265  34 18   7.8   4.3
 19000 -26.4 -15.5  285  30 15   7.2   4.0 | -27.7 -17.9  265  32 17   7.8   4.3
 18500 -25.3 -13.5  285  29 15   7.2   4.0 | -26.5 -15.7  265  30 16   7.8   4.3
 18000 -24.3 -11.7  290  29 15   7.0   3.8 | -25.3 -13.5  265  28 15   7.3   4.0
 17500 -23.3  -9.9  290  29 15   6.8   3.7 | -24.3 -11.7  270  26 13   6.7   3.7
 17000 -22.3  -8.1  290  29 15   6.8   3.7 | -23.4 -10.1  275  23 12   6.7   3.7
 16500 -21.3  -6.3  290  28 14   6.6   3.6 | -22.3  -8.1  280  22 11   7.0   3.8
 16000 -20.3  -4.5  295  28 14   6.7   3.7 | -21.3  -6.3  290  21 11   6.9   3.8
 15500 -18.8  -1.8  295  27 14   6.5   3.5 | -19.6  -3.3  295  21 11   8.2   4.5
 15000 -17.9  -0.2  295  27 14   6.5   3.6 | -18.4  -1.1  300  21 11   8.2   4.5
 14500 -16.9   1.6  295  27 14   6.7   3.7 | -17.2   1.0  300  22 11   7.3   4.0
 14000 -15.9   3.4  300  26 14   6.7   3.7 | -16.1   3.0  305  23 12   7.5   4.1
 13500 -14.9   5.2  300  27 14   6.2   3.4 | -15.0   5.0  305  25 13   6.9   3.8
 13000 -14.0   6.8  300  27 14   6.2   3.4 | -14.0   6.8  305  27 14   7.0   3.9
 12500 -13.0   8.6  305  27 14   6.9   3.8 | -13.0   8.6  305  28 14   5.8   3.2
 12000 -12.0  10.4  300  28 14   7.0   3.8 | -12.2  10.0  305  29 15   5.9   3.2
 11500 -11.1  12.0  300  28 14   5.4   3.0 | -11.3  11.7  305  29 15   5.5   3.0
 11000 -10.2  13.6  305  28 14   5.7   3.1 | -10.5  13.1  305  29 15   5.8   3.2
 10500  -9.5  14.9  300  27 14   3.6   2.0 |  -9.9  14.2  300  28 14   3.0   1.6
 10250  -9.3  15.3  300  26 14   3.4   1.9 |  -9.6  14.7  300  27 14   2.9   1.6
 10000  -9.0  15.8  300  26 13   5.2   2.9 |  -9.4  15.1  300  26 14   4.4   2.4
  9750  -8.5  16.7  300  25 13   5.0   2.7 |  -9.0  15.8  300  25 13   4.2   2.3
  9500  -8.3  17.1  300  24 12   2.9   1.6 |  -8.8  16.2  300  23 12   2.5   1.4
  9250  -8.0  17.6  295  23 12   3.5   1.9 |  -8.6  16.5  295  21 11   2.8   1.5
  9000  -7.8  18.0  295  22 11   3.2   1.7 |  -8.4  16.9  295  20 10   3.2   1.8
  8750  -7.6  18.3  295  20 10   2.6   1.4 |  -8.1  17.4  295  17  9   3.2   1.8
  8500  -7.4  18.7  290  18  9   2.4   1.3 |  -7.9  17.8  290  15  8   2.7   1.5
  8250  -7.2  19.0  290  16  8   2.4   1.3 |  -7.7  18.1  285  12  6   2.6   1.4
  8000  -7.0  19.4  285  15  8   3.3   1.8 |  -7.5  18.5  280  10  5   4.4   2.4
  7750  -6.7  19.9  285  12  6   4.2   2.3 |  -7.0  19.4  270   7  4   7.2   3.9
  7500  -6.4  20.5  280   9  5   3.9   2.1 |  -6.5  20.3  255   6  3   7.5   4.1
  7250  -6.1  21.0  280   7  4   4.5   2.5 |  -5.9  21.4  235   5  3   7.6   4.2
  7000  -5.7  21.7  280   4  2   4.8   2.6 |  -5.3  22.5  210   4  2   8.6   4.7
  6750  -5.4  22.3  270   2  1   6.2   3.4 |  -4.7  23.5  175   4  2   6.9   3.8
  6500  -4.8  23.4  000   0  0   6.3   3.5 |  -4.3  24.3  145   4  2   4.7   2.6
  6250  -4.5  23.9  115   1  1   1.9   1.0 |  -4.0  24.8  125   5  3   3.7   2.0
  6000  -4.5  23.9  130   2  1   0.9   0.5 |  -3.8  25.2  115   5  3   3.2   1.8
  5750  -4.4  24.1  140   2  1  -1.8  -1.0 |  -3.6  25.5  105   5  3   2.1   1.2
  5500  -5.0  23.0  170   3  2 -16.0  -8.8 |  -3.6  25.5  110   5  2   0.2   0.1

           12/28/2014 at 1400 MST          |       12/28/2014 at 1700 MST
                                           |
K index... +2.7  LI... +2.2                | K index... +10.7  LI... +0.9
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 -54.6 -66.3  280  40 21   1.6   0.9 | -54.3 -65.7  290  42 22   2.1   1.2
 45000 -52.2 -62.0  285  56 29   1.6   0.9 | -50.9 -59.6  290  61 31   2.1   1.2
 40000 -51.1 -60.0  280  67 35   0.6   0.3 | -50.4 -58.7  280  63 32   0.1   0.0
 38000 -50.8 -59.4  280  72 37  -1.0  -0.5 | -50.4 -58.7  280  63 33   0.4   0.2
 36000 -51.7 -61.1  280  76 39  -1.6  -0.9 | -50.1 -58.2  280  67 35   0.5   0.3
 34000 -52.7 -62.9  280  81 42  -1.6  -0.9 | -49.8 -57.6  285  71 37   0.5   0.3
 32000 -51.1 -60.0  280  81 42   4.2   2.3 | -49.1 -56.4  285  76 39   1.6   0.9
 30000 -48.6 -55.5  285  80 41   4.2   2.3 | -48.0 -54.4  285  82 42   1.7   0.9
 29000 -47.1 -52.8  285  78 40   5.7   3.1 | -47.0 -52.6  290  83 43   4.7   2.6
 28000 -45.4 -49.7  285  74 38   5.7   3.1 | -45.6 -50.1  290  82 42   4.8   2.6
 27000 -43.6 -46.5  285  70 36   5.7   3.1 | -44.2 -47.6  290  82 42   4.8   2.6
 26000 -42.0 -43.6  285  66 34   4.8   2.6 | -42.7 -44.9  290  80 41   4.5   2.4
 25000 -40.5 -40.9  285  61 32   4.7   2.6 | -41.4 -42.5  290  75 38   4.3   2.4
 24000 -39.1 -38.4  285  56 29   4.7   2.6 | -40.2 -40.4  290  69 36   4.3   2.4
 23000 -37.7 -35.9  285  51 26   5.4   3.0 | -38.9 -38.0  290  63 33   4.1   2.3
 22000 -36.0 -32.8  285  48 25   5.5   3.0 | -37.7 -35.9  285  53 27   4.0   2.2
 21000 -34.4 -29.9  285  44 23   5.6   3.1 | -36.5 -33.7  285  43 22   4.1   2.2
 20000 -32.4 -26.3  285  40 21   8.3   4.6 | -34.8 -30.6  280  34 18   9.2   5.1
 19500 -31.1 -24.0  280  38 19   8.3   4.5 | -33.5 -28.3  275  32 17   8.9   4.9
 19000 -29.9 -21.8  280  35 18   8.3   4.5 | -32.1 -25.8  275  30 15   8.9   4.9
 18500 -28.7 -19.7  275  33 17   8.3   4.5 | -30.8 -23.4  270  28 14   8.9   4.9
 18000 -27.4 -17.3  275  31 16   8.5   4.7 | -29.5 -21.1  270  25 13   9.0   4.9
 17500 -26.1 -15.0  270  30 15   9.2   5.1 | -28.1 -18.6  270  27 14   9.4   5.2
 17000 -24.7 -12.5  270  28 14   9.2   5.1 | -26.7 -16.1  270  29 15   9.4   5.2
 16500 -23.4 -10.1  270  27 14   8.7   4.8 | -25.3 -13.5  270  31 16   9.2   5.0
 16000 -22.1  -7.8  270  25 13   8.7   4.8 | -23.9 -11.0  275  34 18   9.2   5.0
 15500 -20.2  -4.4  275  23 12   8.2   4.5 | -22.0  -7.6  280  38 20   8.1   4.4
 15000 -19.0  -2.2  280  22 11   8.3   4.6 | -20.8  -5.4  280  40 20   8.3   4.5
 14500 -17.8  -0.0  285  22 11   7.1   3.9 | -19.6  -3.3  280  41 21   7.3   4.0
 14000 -16.7   1.9  285  23 12   7.3   4.0 | -18.5  -1.3  280  40 21   7.4   4.0
 13500 -15.7   3.7  290  24 12   6.8   3.7 | -17.4   0.7  280  40 20   7.8   4.3
 13000 -14.7   5.5  290  25 13   6.8   3.7 | -16.2   2.8  280  39 20   7.9   4.3
 12500 -13.7   7.3  290  26 14   7.3   4.0 | -15.0   5.0  280  38 19   7.7   4.2
 12000 -12.6   9.3  290  28 14   7.4   4.1 | -13.9   7.0  280  37 19   7.7   4.2
 11500 -11.5  11.3  290  29 15   6.6   3.6 | -12.7   9.1  275  36 18   8.1   4.4
 11000 -10.6  12.9  290  28 15   6.7   3.7 | -11.5  11.3  275  32 16   8.2   4.5
 10500  -9.8  14.4  285  27 14   4.5   2.5 | -10.3  13.5  275  28 15   7.8   4.3
 10250  -9.4  15.1  285  26 14   4.3   2.4 |  -9.8  14.4  275  26 14   7.5   4.1
 10000  -9.1  15.6  285  26 13   4.8   2.6 |  -9.2  15.4  275  25 13   8.6   4.7
  9750  -8.8  16.2  285  24 12   4.5   2.5 |  -8.5  16.7  280  23 12   8.1   4.5
  9500  -8.5  16.7  280  21 11   4.0   2.2 |  -8.0  17.6  280  21 11   6.7   3.7
  9250  -8.2  17.2  280  19 10   4.1   2.3 |  -7.5  18.5  280  19 10   7.1   3.9
  9000  -7.8  18.0  275  16  8   4.0   2.2 |  -7.0  19.4  280  17  9   6.8   3.7
  8750  -7.5  18.5  270  14  7   4.7   2.6 |  -6.5  20.3  280  15  8   6.2   3.4
  8500  -7.1  19.2  260  12  6   5.4   3.0 |  -6.0  21.2  275  13  7   6.0   3.3
  8250  -6.7  19.9  250  11  5   4.9   2.7 |  -5.6  21.9  270  12  6   5.9   3.3
  8000  -6.3  20.7  235  10  5   6.3   3.4 |  -5.1  22.8  270  10  5   6.4   3.5
  7750  -5.8  21.6  220   9  5   7.7   4.2 |  -4.6  23.7  260   8  4   7.4   4.0
  7500  -5.2  22.6  215   9  5   7.4   4.1 |  -4.0  24.8  255   7  4   7.5   4.1
  7250  -4.7  23.5  205   9  4   7.5   4.1 |  -3.5  25.7  245   7  3   7.4   4.0
  7000  -4.1  24.6  200   8  4   8.6   4.7 |  -2.9  26.8  235   6  3   7.4   4.1
  6750  -3.4  25.9  190   8  4   6.9   3.8 |  -2.4  27.7  220   5  3   6.1   3.4
  6500  -3.0  26.6  180   7  4   5.4   3.0 |  -2.0  28.4  205   5  2   5.8   3.2
  6250  -2.7  27.1  165   8  4   2.8   1.5 |  -1.6  29.1  190   5  2   2.0   1.1
  6000  -2.7  27.1  155   7  4  -0.3  -0.1 |  -1.8  28.8  185   5  2  -1.7  -0.9
  5750  -2.7  27.1  150   7  3   2.0   1.1 |  -1.9  28.6  180   5  3  -0.5  -0.3
  5500  -2.5  27.5  140   5  2   5.5   3.0 |  -2.2  28.0  170   4  2  -8.5  -4.7
________________________________________________________________________________

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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