Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 250034
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1834 MDT Tuesday, March 24, 2015

This forecast is for Wednesday, March 25, 2015:

If the trigger temperature of 47.1 F/8.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5485 ft MSL (178 ft AGL)

Forecast maximum temperature................... 43.0 F/6.6 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 1400 MDT
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 Thursday 03/26..... Good

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... Becoming poor by 0900 MDT
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 24037 ft MSL (18730 ft AGL)
Wave soaring outlook for Thursday 03/26........ Fair

Remarks...

Sunrise/Sunset.................... 06:55:08 / 19:15:22 MDT
Total possible sunshine........... 12 hr 20 min 14 sec (740 min 14 sec)
Altitude of sun at 13:05:25 MDT... 52.15 degrees

Upper air data from numerical model forecast valid on 03/25/2015 at 0600 MDT

Freezing level.................. 8066 ft MSL (2759 ft AGL)
Convective condensation level... 10984 ft MSL (5677 ft AGL)
Lifted condensation level....... 9630 ft MSL (4324 ft AGL)
Lifted index.................... +8.5
K index......................... +15.8

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  -53.3 -63.9   295   21   11   1.8   1.0      M     M       M      M    M
 45000  -50.6 -59.1   295   21   11   2.0   1.1      M     M       M      M    M
 40000  -56.2 -69.2   275   45   23  -4.3  -2.3      M     M       M      M    M
 38000  -58.1 -72.6   270   54   28   0.7   0.4      M     M       M      M    M
 36000  -57.7 -71.9   265   53   27   0.6   0.4      M     M       M      M    M
 34000  -57.2 -71.0   255   54   28   4.4   2.4      M     M       M      M    M
 32000  -52.9 -63.2   255   53   27   7.1   3.9      M     M       M      M    M
 30000  -48.6 -55.5   255   52   27   9.2   5.1   27.1  80.8    15.7      M    M
 29000  -45.7 -50.3   250   50   26   9.5   5.2   26.9  80.4    15.7      M    M
 28000  -42.9 -45.2   245   49   25   9.5   5.2   26.8  80.2    15.8      M    M
 27000  -40.0 -40.0   240   47   24   9.6   5.3   26.8  80.2    16.0      M    M
 26000  -37.4 -35.3   245   46   24   8.3   4.6   26.3  79.4    15.9      M    M
 25000  -34.9 -30.8   250   46   24   8.4   4.6   25.7  78.3    15.6      M    M
 24000  -32.4 -26.3   255   46   24   8.4   4.6   25.3  77.5    15.4      M    M
 23000  -30.1 -22.2   260   46   24   7.3   4.0   24.5  76.1    15.0      M    M
 22000  -27.9 -18.2   265   46   23   7.3   4.0   23.6  74.4    14.4      M    M
 21000  -25.8 -14.4   270   46   24   7.3   4.0   22.8  73.0    13.8      M    M
 20000  -24.0 -11.2   270   46   24   5.5   3.0   21.3  70.4    12.8      M    M
 19500  -23.2  -9.8   275   45   23   5.5   3.0   20.6  69.0    12.2      M    M
 19000  -22.4  -8.3   275   45   23   5.5   3.0   19.8  67.7    11.6      M    M
 18500  -21.6  -6.9   275   45   23   5.6   3.1   19.1  66.4    11.1      M    M
 18000  -20.8  -5.4   275   45   23   4.4   2.4   18.3  65.0    10.4      M    M
 17500  -19.9  -3.8   280   44   23   4.4   2.4   17.0  62.6     9.3      M    M
 17000  -19.1  -2.4   280   43   22   5.8   3.2   16.2  61.1     8.6      M    M
 16500  -18.3  -0.9   280   42   21   5.7   3.1   15.5  59.9     8.1      M    M
 16000  -17.4   0.7   280   40   21   5.7   3.1   14.8  58.7     7.5      M    M
 15500  -16.6   2.1   280   39   20   5.7   3.1   14.1  57.4     6.9      M    M
 15000  -15.7   3.7   285   37   19   5.9   3.2   13.5  56.2     6.3      M    M
 14500  -14.9   5.2   285   35   18   6.0   3.3   12.8  55.1     5.8      M    M
 14000  -14.0   6.8   285   33   17   6.2   3.4   12.2  54.0     5.2      M    M
 13500  -13.0   8.6   290   31   16   6.5   3.6   11.6  53.0     4.7      M    M
 13000  -12.1  10.2   295   29   15   6.8   3.7   11.1  52.0     4.3      M    M
 12500  -10.9  12.4   300   26   13   7.9   4.3   10.8  51.4     3.9      M    M
 12000   -9.8  14.4   305   23   12   7.9   4.3   10.5  50.8     3.7      M    M
 11500   -8.6  16.5   305   21   11   8.1   4.4   10.2  50.3     3.4      M    M
 11000   -7.4  18.7   310   19   10   7.6   4.2    9.9  49.9     3.2      M    M
 10500   -6.4  20.5   310   17    9   6.6   3.6    9.4  49.0     2.7      M    M
 10250   -5.9  21.4   310   17    9   5.6   3.1    9.2  48.5     2.5      M    M
 10000   -5.4  22.3   310   16    8   9.7   5.3    8.9  48.1     2.2      M    M
  9750   -4.5  23.9   315   15    8  11.0   6.0    9.1  48.4     2.4      M    M
  9500   -3.9  25.0   315   14    7   7.8   4.3    9.0  48.2     2.3      M    M
  9250   -3.3  26.1   315   14    7   8.5   4.7    8.9  48.0     2.2      M    M
  9000   -2.7  27.1   320   13    7   8.3   4.6    8.8  47.8     2.1      M    M
  8750   -2.0  28.4   325   13    6   9.4   5.2    8.7  47.7     2.0      M    M
  8500   -1.3  29.7   330   12    6  10.0   5.5    8.7  47.7     2.0      M    M
  8250   -0.6  30.9   335   12    6   9.9   5.4    8.7  47.7     2.0      M    M
  8000    0.1  32.2   340   13    7   9.9   5.4    8.7  47.7     2.0      M    M
  7750    0.9  33.6   345   13    7   9.1   5.0    8.7  47.7     2.0      M    M
  7500    1.5  34.7   345   14    7   8.5   4.6    8.6  47.6     1.9      M    M
  7250    2.2  36.0   345   14    7   9.3   5.1    8.6  47.4     1.8      M    M
  7000    2.9  37.2   345   15    8   9.9   5.4    8.6  47.4     1.8      M    M
  6750    3.6  38.5   345   15    8   9.5   5.2    8.6  47.4     1.8      M    M
  6500    4.3  39.7   345   15    8   8.4   4.6    8.5  47.3     1.8      M    M
  6250    4.8  40.6   345   16    8   7.0   3.8    8.3  47.0     1.6      M    M
  6000    5.3  41.5   345   15    8   7.4   4.1    8.1  46.6     1.4      M    M
  5750    5.8  42.4   345   15    8   5.2   2.9    7.9  46.3     1.1      M    M
  5500    5.9  42.6   345   14    7  -4.6  -2.5    7.3  45.1     0.5      M    M

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

           03/25/2015 at 0900 MDT          |       03/25/2015 at 1200 MDT
                                           |
K index... +7.8  LI... +277.2              | K index... +8.7  LI... +273.5
CAPE... 0.0  CIN... M                      | CAPE... +4.8  CIN... -0.2
                                           |
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  320  14  7   1.3   0.7 | -54.2 -65.6  315  14  7   0.6   0.3
 45000 -51.4 -60.5  315   8  4   1.3   0.7 | -53.3 -63.9  295  16  8   0.6   0.3
 40000 -52.4 -62.3  280  31 16  -0.8  -0.5 | -51.3 -60.3  295  28 15   1.3   0.7
 38000 -53.1 -63.6  275  41 21  -2.6  -1.4 | -50.9 -59.6  290  33 17  -0.7  -0.4
 36000 -54.8 -66.6  260  47 24  -2.5  -1.4 | -51.3 -60.3  275  37 19  -0.7  -0.4
 34000 -56.3 -69.3  255  55 28   0.1   0.1 | -51.7 -61.1  265  44 23  -1.2  -0.6
 32000 -52.7 -62.9  255  53 27   6.3   3.4 | -50.2 -58.4  250  50 26   3.2   1.7
 30000 -48.9 -56.0  255  51 26   7.4   4.1 | -48.2 -54.8  240  59 30   2.9   1.6
 29000 -46.5 -51.7  255  51 26   8.2   4.5 | -46.2 -51.2  240  59 31   6.2   3.4
 28000 -44.0 -47.2  255  51 26   8.3   4.5 | -44.3 -47.7  240  59 30   6.2   3.4
 27000 -41.5 -42.7  255  51 26   8.2   4.5 | -42.5 -44.5  240  59 30   6.1   3.4
 26000 -39.0 -38.2  250  50 26   8.7   4.8 | -40.3 -40.5  240  57 29   7.8   4.3
 25000 -36.4 -33.5  250  49 25   8.7   4.8 | -38.0 -36.4  240  55 28   7.8   4.3
 24000 -33.8 -28.8  245  48 25   8.6   4.7 | -35.7 -32.3  240  52 27   7.7   4.2
 23000 -31.6 -24.9  250  47 24   5.8   3.2 | -33.9 -29.0  245  47 24   3.9   2.1
 22000 -29.9 -21.8  260  47 24   5.7   3.1 | -32.8 -27.0  250  38 19   3.8   2.1
 21000 -28.2 -18.8  270  49 25   5.7   3.1 | -31.7 -25.1  255  29 15   3.6   2.0
 20000 -26.7 -16.1  270  47 24   5.0   2.7 | -30.2 -22.4  265  26 13   5.5   3.0
 19500 -26.0 -14.8  270  45 23   5.0   2.8 | -29.4 -20.9  270  25 13   5.5   3.0
 19000 -25.2 -13.4  270  44 22   5.0   2.8 | -28.6 -19.5  275  25 13   5.5   3.0
 18500 -24.1 -11.4  270  41 21   5.2   2.9 | -27.7 -17.9  280  25 13   4.9   2.7
 18000 -23.3  -9.9  270  39 20   5.6   3.0 | -26.6 -15.9  280  25 13  10.7   5.9
 17500 -22.5  -8.5  270  37 19   5.4   2.9 | -25.1 -13.2  275  25 13  10.3   5.7
 17000 -21.5  -6.7  270  36 18   7.4   4.1 | -23.6 -10.5  275  25 13   7.4   4.1
 16500 -20.5  -4.9  270  34 18   7.2   4.0 | -22.7  -8.9  285  25 13   5.9   3.2
 16000 -19.4  -2.9  270  33 17   7.5   4.1 | -21.9  -7.4  295  26 14   6.2   3.4
 15500 -18.3  -0.9  275  31 16   7.5   4.1 | -20.8  -5.4  300  25 13   7.6   4.2
 15000 -17.1   1.2  275  30 15   7.2   3.9 | -19.1  -2.4  305  24 12   7.4   4.1
 14500 -16.1   3.0  280  29 15   6.8   3.7 | -18.1  -0.6  315  23 12   7.3   4.0
 14000 -15.1   4.8  290  29 15   6.7   3.7 | -17.0   1.4  320  22 12   7.3   4.0
 13500 -14.1   6.6  295  28 15   6.6   3.6 | -15.9   3.4  325  22 11   7.3   4.0
 13000 -13.1   8.4  300  29 15   6.4   3.5 | -14.8   5.4  330  21 11   7.4   4.1
 12500 -12.2  10.0  310  28 14   5.8   3.2 | -13.7   7.3  335  21 11   7.7   4.2
 12000 -11.3  11.7  315  27 14   6.3   3.4 | -12.6   9.3  340  21 11   7.6   4.2
 11500 -10.2  13.6  320  26 13   7.6   4.2 | -11.5  11.3  340  21 11   7.4   4.1
 11000  -9.1  15.6  325  24 13   6.9   3.8 | -10.4  13.3  345  21 11   7.4   4.1
 10500  -8.2  17.2  325  23 12   5.3   2.9 |  -9.3  15.3  345  21 11   7.8   4.3
 10250  -7.8  18.0  330  22 11   5.8   3.2 |  -8.8  16.2  345  21 11   6.0   3.3
 10000  -7.4  18.7  330  21 11   3.6   2.0 |  -8.5  16.7  345  21 11   4.1   2.2
  9750  -7.2  19.0  330  21 11   6.2   3.4 |  -8.1  17.4  350  21 11   7.5   4.1
  9500  -6.5  20.3  330  20 10  10.2   5.6 |  -7.4  18.7  355  20 10  10.0   5.5
  9250  -5.8  21.6  330  19 10   8.8   4.8 |  -6.7  19.9  360  19 10   8.5   4.7
  9000  -5.2  22.6  325  19 10   7.4   4.0 |  -6.2  20.8  005  19 10   7.5   4.1
  8750  -4.6  23.7  325  19 10   7.7   4.2 |  -5.6  21.9  005  20 10   9.8   5.4
  8500  -4.0  24.8  320  19 10   9.0   5.0 |  -4.7  23.5  005  20 10  11.7   6.4
  8250  -3.4  25.9  320  19 10   8.2   4.5 |  -3.9  25.0  010  20 10  10.3   5.7
  8000  -2.8  27.0  320  19 10   7.5   4.1 |  -3.2  26.2  010  20 10   9.6   5.3
  7750  -2.2  28.0  315  18  9   8.3   4.6 |  -2.4  27.7  010  20 10  10.1   5.6
  7500  -1.6  29.1  315  18  9   9.1   5.0 |  -1.7  28.9  010  20 10  10.3   5.6
  7250  -0.9  30.4  315  18  9   9.1   5.0 |  -0.9  30.4  010  19 10  10.1   5.5
  7000  -0.2  31.6  315  17  9   9.4   5.1 |  -0.2  31.6  010  19 10  10.2   5.6
  6750   0.5  32.9  320  17  9   9.0   5.0 |   0.6  33.1  010  19 10   9.8   5.4
  6500   1.1  34.0  320  16  8   9.5   5.2 |   1.3  34.3  010  19 10  10.5   5.8
  6250   1.9  35.4  320  15  8  10.2   5.6 |   2.2  36.0  010  19 10  11.8   6.5
  6000   2.6  36.7  325  13  7  10.0   5.5 |   3.0  37.4  010  19 10  10.6   5.8
  5750   3.3  37.9  325  12  6  10.5   5.7 |   3.9  39.0  010  18  9  14.1   7.7
  5500   4.1  39.4  325  10  5  12.2   6.7 |   5.3  41.5  010  17  9  23.9  13.1

           03/25/2015 at 1500 MDT          |       03/25/2015 at 1800 MDT
                                           |
K index... +10.5  LI... +273.3             | K index... +9.6  LI... +274.1
CAPE... +0.9  CIN... -4.1                  | CAPE... 0.0  CIN... -0.8
                                           |
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 -53.6 -64.5  310  18  9   2.0   1.1 | -53.9 -65.0  310  24 12   1.4   0.7
 45000 -50.6 -59.1  300  23 12   2.0   1.1 | -51.7 -61.1  305  28 15   1.3   0.7
 40000 -50.3 -58.5  295  32 17   0.0   0.0 | -50.8 -59.4  310  28 14   0.6   0.3
 38000 -50.3 -58.5  295  34 18   0.2   0.1 | -50.6 -59.1  315  29 15  -0.2  -0.1
 36000 -50.1 -58.2  295  33 17   0.2   0.1 | -50.7 -59.3  325  33 17  -0.2  -0.1
 34000 -50.0 -58.0  295  32 16   0.1   0.0 | -50.9 -59.6  330  37 19  -0.4  -0.2
 32000 -49.2 -56.6  285  30 16   1.6   0.9 | -50.2 -58.4  345  44 22   1.2   0.7
 30000 -48.1 -54.6  275  30 15   2.8   1.5 | -49.4 -56.9  355  53 27   4.2   2.3
 29000 -46.8 -52.2  270  29 15   4.3   2.3 | -47.4 -53.3  360  55 28   6.5   3.6
 28000 -45.5 -49.9  265  28 14   4.3   2.3 | -45.5 -49.9  360  57 29   6.5   3.6
 27000 -44.3 -47.7  260  27 14   4.3   2.3 | -43.5 -46.3  360  59 30   6.5   3.6
 26000 -42.6 -44.7  255  27 14   6.4   3.5 | -41.7 -43.1  360  56 29   5.7   3.1
 25000 -40.7 -41.3  255  27 14   6.4   3.5 | -40.0 -40.0  355  51 26   5.7   3.1
 24000 -38.8 -37.8  255  27 14   6.4   3.5 | -38.3 -36.9  355  47 24   5.7   3.1
 23000 -36.8 -34.2  265  24 12   6.6   3.6 | -36.5 -33.7  350  42 22   6.5   3.6
 22000 -34.8 -30.6  290  21 11   6.6   3.6 | -34.5 -30.1  340  39 20   6.5   3.6
 21000 -32.9 -27.2  315  24 12   6.6   3.6 | -32.6 -26.7  335  35 18   6.7   3.7
 20000 -30.7 -23.3  325  25 13   7.5   4.1 | -30.2 -22.4  335  33 17   8.3   4.6
 19500 -29.6 -21.3  330  25 13   7.5   4.1 | -28.9 -20.0  335  32 17   8.3   4.5
 19000 -28.5 -19.3  335  25 13   7.5   4.1 | -27.7 -17.9  335  31 16   8.3   4.6
 18500 -27.4 -17.3  340  25 13   7.4   4.1 | -26.5 -15.7  335  30 16   8.2   4.5
 18000 -26.2 -15.2  340  25 13   8.5   4.7 | -25.3 -13.5  335  29 15   7.1   3.9
 17500 -24.9 -12.8  345  25 13   8.4   4.6 | -24.3 -11.7  340  27 14   7.1   3.9
 17000 -23.6 -10.5  345  26 13   8.4   4.6 | -23.2  -9.8  345  26 13   8.0   4.4
 16500 -22.4  -8.3  345  27 14   8.4   4.6 | -21.9  -7.4  350  25 13   8.2   4.5
 16000 -21.2  -6.2  345  28 14   8.2   4.5 | -20.1  -4.2  355  25 13   8.0   4.4
 15500 -19.4  -2.9  345  28 15   8.0   4.4 | -18.9  -2.0  355  24 13   8.0   4.4
 15000 -18.2  -0.8  345  29 15   7.9   4.3 | -17.8  -0.0  355  24 12   7.8   4.3
 14500 -17.1   1.2  345  29 15   7.8   4.3 | -16.6   2.1  355  24 12   7.9   4.3
 14000 -15.9   3.4  345  29 15   7.2   4.0 | -15.5   4.1  355  24 12   6.9   3.8
 13500 -14.9   5.2  345  29 15   6.9   3.8 | -14.5   5.9  355  25 13   6.6   3.6
 13000 -13.9   7.0  345  29 15   6.6   3.6 | -13.5   7.7  355  26 13   7.2   3.9
 12500 -13.0   8.6  350  29 15   6.5   3.5 | -12.4   9.7  355  26 13   7.5   4.1
 12000 -12.0  10.4  350  28 15   6.9   3.8 | -11.3  11.7  360  25 13   7.6   4.2
 11500 -11.0  12.2  350  28 14   7.2   3.9 | -10.2  13.6  360  23 12   7.7   4.2
 11000  -9.9  14.2  350  27 14   7.4   4.1 |  -9.1  15.6  005  20 10   7.8   4.3
 10500  -8.8  16.2  350  25 13   8.0   4.4 |  -8.0  17.6  005  17  9   8.4   4.6
 10250  -8.2  17.2  350  24 12   5.6   3.1 |  -7.4  18.7  005  15  8   5.4   3.0
 10000  -7.9  17.8  350  24 12   4.3   2.4 |  -7.1  19.2  005  15  7   4.8   2.6
  9750  -7.5  18.5  355  22 12   8.3   4.6 |  -6.6  20.1  005  14  7   9.4   5.2
  9500  -6.8  19.8  355  21 11  10.2   5.6 |  -5.8  21.6  005  13  7  10.8   5.9
  9250  -6.1  21.0  355  19 10   8.6   4.7 |  -5.1  22.8  005  13  7   9.1   5.0
  9000  -5.5  22.1  355  18  9   7.5   4.1 |  -4.5  23.9  360  13  6   7.8   4.3
  8750  -4.9  23.2  355  18  9   9.7   5.3 |  -3.8  25.2  360  12  6   9.8   5.4
  8500  -4.1  24.6  355  18  9  11.1   6.1 |  -3.1  26.4  360  12  6  10.6   5.8
  8250  -3.4  25.9  355  18  9  10.0   5.5 |  -2.3  27.9  360  12  6  10.2   5.6
  8000  -2.6  27.3  355  18  9   9.6   5.3 |  -1.6  29.1  360  12  6  10.0   5.5
  7750  -1.9  28.6  355  18  9   9.9   5.4 |  -0.8  30.6  360  12  6  10.4   5.7
  7500  -1.2  29.8  355  17  9  10.0   5.5 |  -0.0  32.0  355  12  6  10.1   5.5
  7250  -0.4  31.3  355  17  9  10.1   5.5 |   0.7  33.3  355  12  6   9.6   5.3
  7000   0.3  32.5  355  17  9  10.0   5.5 |   1.4  34.5  355  12  6   9.5   5.2
  6750   1.1  34.0  355  17  9  10.4   5.7 |   2.1  35.8  355  11  6  10.1   5.5
  6500   1.9  35.4  355  17  9  10.7   5.8 |   2.9  37.2  355  11  6  10.2   5.6
  6250   2.7  36.9  355  17  9  10.5   5.7 |   3.6  38.5  355  11  6   9.3   5.1
  6000   3.4  38.1  355  16  8  10.2   5.6 |   4.4  39.9  355  11  6  10.6   5.8
  5750   4.3  39.7  355  16  8  16.1   8.8 |   5.2  41.4  350  11  5  12.9   7.1
  5500   5.9  42.6  355  15  8  26.8  14.7 |   6.2  43.2  350  10  5  13.6   7.4
________________________________________________________________________________

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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