Jump to content
  • Member Statistics

    17,609
    Total Members
    7,904
    Most Online
    NH8550
    Newest Member
    NH8550
    Joined

March 5 Snow Thread-Model Discussion ONLY


stormtracker

Recommended Posts

  • Replies 1.1k
  • Created
  • Last Reply

Now that's not exactly the evolution I expected in the NAM, especially after seeing the early part.  So looks like a general ~6"+ or there about for the DC area (just going by the snow maps...I know, I know!).  A layer of sleet underneath that to start?  Ironically, it's similar to the Euro in that the timing of the heavy precip is during much of the day Thursday when the cold air is in place.  Looks like a good trend.

 

Couple of questions, if anyone had these details:  first, how cold does it get us during Thursday...and second, approx. how much sleet is there prior to going over to snow?  Looks like it's snowing by around 12Z, I believe.

Link to comment
Share on other sites

12Z at BWI is certainly all snow (skewt confirms no warming in between levels)

LEV PRES  HGHT  TEMP  DEWP  RH  DD   WETB DIR SPD THETA THE-V THE-W THE-E   W     mb     m     C     C    %   C     C  deg knt   K     K     K     K    g/kg-------------------------------------------------------------------------------SFC 1015    40   0.2  -1.0  91  1.2  -0.3 343  10 272.2 272.7 272.1 281.6  3.48  1 1000   160  -0.9  -2.3  90  1.4  -1.4 346  16 272.3 272.8 271.8 281.0  3.23  2  950   567  -4.5  -5.4  93  0.9  -4.8 349  24 272.6 273.0 271.1 279.9  2.68  3  900   990  -7.8  -9.3  89  1.5  -8.3 340  30 273.4 273.8 270.7 279.2  2.09  4  850  1439  -3.0  -3.2  98  0.3  -3.1 279  16 283.0 283.6 278.2 293.0  3.54  5  800  1922  -1.9  -2.1  99  0.2  -2.0 251  19 289.1 289.8 281.7 300.9  4.10  6  750  2434  -1.6  -1.7  99  0.1  -1.7 230  31 294.8 295.6 284.5 308.0  4.49  7  700  2985  -0.5  -0.7  99  0.2  -0.6 233  60 301.9 302.9 287.9 317.6  5.21  8  650  3577  -2.2  -2.4  99  0.2  -2.3 236  76 306.4 307.3 289.2 321.6  4.94  9  600  4210  -5.1  -5.3  99  0.1  -5.2 242  86 310.2 311.0 289.9 323.7  4.30 10  550  4888  -9.3 -10.0  95  0.7  -9.6 247  96 313.1 313.7 289.8 323.5  3.26 11  500  5621 -12.7 -13.7  92  1.1 -13.0 245 100 317.6 318.1 290.6 326.3  2.64
Link to comment
Share on other sites

I am still not sure how that second batch of precip manages to readvance north despite strong CAA at 850mb.     The smarter models  keep the northern edge stalled or drifting south the whole time.  

 

In other words, The NAM is wrong.

Link to comment
Share on other sites

12Z at BWI is certainly all snow (skewt confirms no warming in between levels)

LEV PRES  HGHT  TEMP  DEWP  RH  DD   WETB DIR SPD THETA THE-V THE-W THE-E   W
     mb     m     C     C    %   C     C  deg knt   K     K     K     K    g/kg
-------------------------------------------------------------------------------
SFC 1015    40   0.2  -1.0  91  1.2  -0.3 343  10 272.2 272.7 272.1 281.6  3.48
  1 1000   160  -0.9  -2.3  90  1.4  -1.4 346  16 272.3 272.8 271.8 281.0  3.23
  2  950   567  -4.5  -5.4  93  0.9  -4.8 349  24 272.6 273.0 271.1 279.9  2.68
  3  900   990  -7.8  -9.3  89  1.5  -8.3 340  30 273.4 273.8 270.7 279.2  2.09
  4  850  1439  -3.0  -3.2  98  0.3  -3.1 279  16 283.0 283.6 278.2 293.0  3.54
  5  800  1922  -1.9  -2.1  99  0.2  -2.0 251  19 289.1 289.8 281.7 300.9  4.10
  6  750  2434  -1.6  -1.7  99  0.1  -1.7 230  31 294.8 295.6 284.5 308.0  4.49
  7  700  2985  -0.5  -0.7  99  0.2  -0.6 233  60 301.9 302.9 287.9 317.6  5.21
  8  650  3577  -2.2  -2.4  99  0.2  -2.3 236  76 306.4 307.3 289.2 321.6  4.94
  9  600  4210  -5.1  -5.3  99  0.1  -5.2 242  86 310.2 311.0 289.9 323.7  4.30
 10  550  4888  -9.3 -10.0  95  0.7  -9.6 247  96 313.1 313.7 289.8 323.5  3.26
 11  500  5621 -12.7 -13.7  92  1.1 -13.0 245 100 317.6 318.1 290.6 326.3  2.64

Mitch, can you link this site?

Link to comment
Share on other sites

DCA definitely switches over between 12Z and 15Z....here are the soundings from both times

LEV PRES  HGHT  TEMP  DEWP  RH  DD   WETB DIR SPD THETA THE-V THE-W THE-E   W     mb     m     C     C    %   C     C  deg knt   K     K     K     K    g/kg-------------------------------------------------------------------------------SFC 1013    56   0.5  -0.5  93  1.0   0.1 342   9 272.6 273.2 272.6 282.4  3.64  1 1000   160  -0.3  -1.3  93  1.0  -0.7 345  14 272.8 273.4 272.5 282.2  3.47  2  950   568  -3.9  -4.5  96  0.6  -4.1 352  23 273.2 273.7 271.8 281.1  2.87  3  900   991  -7.2  -7.6  97  0.4  -7.3 351  27 274.1 274.5 271.6 280.8  2.40  4  850  1441  -1.9  -2.1  98  0.2  -2.0 281  12 284.2 284.8 279.1 295.1  3.85  5  800  1923  -2.7  -2.8  99  0.2  -2.8 243  12 288.3 289.0 281.1 299.4  3.87  6  750  2438   1.0   0.8  99  0.2   0.9 227  45 297.6 298.6 286.6 313.6  5.41  7  700  2994   0.7   0.6  99  0.2   0.7 234  72 303.3 304.3 288.9 320.5  5.71  8  650  3588  -1.6  -1.7  99  0.2  -1.7 240  80 307.2 308.1 289.7 323.1  5.18  9  600  4221  -5.3  -5.5  99  0.2  -5.4 246  87 309.9 310.7 289.7 323.2  4.22 10  550  4901  -8.4 -11.0  81  2.6  -9.4 247  93 314.1 314.7 289.9 323.8  2.99 11  500  5635 -12.5 -16.8  71  4.2 -13.9 245  94 317.8 318.2 290.2 324.6  2.06
LEV PRES  HGHT  TEMP  DEWP  RH  DD   WETB DIR SPD THETA THE-V THE-W THE-E   W     mb     m     C     C    %   C     C  deg knt   K     K     K     K    g/kg-------------------------------------------------------------------------------SFC 1016    56  -0.6  -2.1  90  1.4  -1.2 333   8 271.3 271.8 271.1 280.0  3.23  1 1000   185  -2.2  -3.3  92  1.1  -2.6 337  11 271.0 271.5 270.6 279.1  3.00  2  950   590  -5.9  -6.7  94  0.8  -6.2 350  17 271.2 271.6 269.8 277.8  2.43  3  900  1010  -9.1 -10.5  89  1.4  -9.5   4  21 272.1 272.4 269.5 277.4  1.90  4  850  1454  -6.4  -7.4  92  1.1  -6.7 315  23 279.5 279.9 274.9 286.7  2.57  5  800  1933  -3.7  -4.1  97  0.4  -3.9 252  14 287.2 287.8 280.1 297.3  3.52  6  750  2443  -2.5  -2.7  99  0.2  -2.6 231  32 293.8 294.6 283.8 306.1  4.18  7  700  2993  -0.8  -0.9  99  0.2  -0.9 230  64 301.6 302.6 287.8 317.1  5.12  8  650  3585  -1.9  -2.1  99  0.2  -2.0 237  79 306.8 307.7 289.5 322.3  5.05  9  600  4219  -5.1  -5.2  99  0.1  -5.1 243  91 310.2 311.1 289.9 323.8  4.32 10  550  4897  -9.0  -9.6  96  0.5  -9.2 246  93 313.4 314.0 290.0 324.2  3.37 11  500  5628 -13.8 -15.1  90  1.3 -14.2 245  98 316.2 316.7 290.0 324.0  2.37
Link to comment
Share on other sites

I am still not sure how that second batch of precip manages to readvance north despite strong CAA at 850mb.     The smarter models  keep the northern edge stalled or drifting south the whole time.  

 

In other words, The NAM is wrong.

 

Wave along the front?  I thought that was main reason for getting significant precip in the cold air, at least; plus the stream of Gulf/Pacific moisture going up and over the front.  Also, the Euro did kind of a similar thing with a second batch of sorts.  Not saying this scenario is absolutely correct, but it is what it is.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...