December 11 Week Event(s)

[NorthArlington101]

Looks decent for what it is looking at the precip map -- http://collaboration.cmc.ec.gc.ca/cmc/cmdn/pcpn_type/pcpn_type_gem_reg.html

Start at hour 22 and go to 28

That would be pretty sweet... looks great. RGEM led the way yesterday.

[yoda]

Looks like DCA is 0.11 QPF if we believe 18z RGEM... approaching 0.15 or a lil more for NE MD

[Cobalt]

3 minutes ago, yoda said:

Looks like DCA is 0.11 QPF if we believe 18z RGEM... approaching 0.15 or a lil more for NE MD

What would ratios be for the storm?

 

[osfan24]

If the NAM keeps trending this much with each run through this time tomorrow, we are going to be looking at a really nice little surprise.

[yoda]

2 minutes ago, Cobalt said:

What would ratios be for the storm?

 

Not sure... prob 10:1... maybe 12:1 if lucky?

[Interstate]

It will only come to fruition if Baltimore country brines the road

[smokeybandit]

They sure brined the hell out of the roads last night

[Scraff]

I have an 8:30 pm reservation tomorrow with The Last Jedi. Should I fly my snow speeder there? LOLz. 

[yoda]

Just now, Scraff said:

I have an 8:30 pm reservation tomorrow with The Last Jedi. Should I fly my snow speeder there? LOLz. 

Perhaps an X-Wing would do better

[Scraff]

5 minutes ago, yoda said:

Perhaps an X-Wing would do better

With our luck, probably will be Tatooine dry anyway. 

[yoda]

11 minutes ago, Scraff said:

With our luck, probably will be Tatooine dry anyway. 

We'll never be like Hoth though

 

[RevWarReenactor]

Wow, yet another event that is going in the right direction at the last minute.

I am not use to this at all.

[NorthArlington101]

FWIW

[AfewUniversesBelowNormal]

RAP is north. Actually a nice event. 

[csnavywx]

Still not enthused about it. Will be putting mainly -FZDZ and SG in the TAF tomorrow morning with the BUFKIT profiles I'm seeing tonight.

Without some seeder feeder or better lift a bit further up in the column, it's going to be hell on snow growth. A few spots might luck out, but I'd really like to see some better saturation in the ice crystal layer.

[yoda]

Looks like SREFs came slightly more west... 0.1 line is just SW of DC

[MD Snow]

6 minutes ago, yoda said:

Looks like SREFs came slightly more west... 0.1 line is just SW of DC

It's weird that both the RAP and HRRR are both pretty far north. I guess they are at the end of their ranges but it's worth noting.  

[mattie g]

1 hour ago, csnavywx said:

Still not enthused about it. Will be putting mainly -FZDZ and SG in the TAF tomorrow morning with the BUFKIT profiles I'm seeing tonight.

Without some seeder feeder or better lift a bit further up in the column, it's going to be hell on snow growth. A few spots might luck out, but I'd really like to see some better saturation in the ice crystal layer.

[yoda]

Special Weather Statement
National Weather Service Baltimore MD/Washington DC
627 PM EST Thu Dec 14 2017

DCZ001-MDZ011-013-014-016-503>506-VAZ052>055-057-501-502-505-506-
150530-
District of Columbia-Southern Baltimore-Prince Georges-
Anne Arundel-Charles-Northwest Montgomery-
Central and Southeast Montgomery-Northwest Howard-
Central and Southeast Howard-
Prince William/Manassas/Manassas Park-Fairfax-
Arlington/Falls Church/Alexandria-Stafford-King George-
Northern Fauquier-Southern Fauquier-Western Loudoun-
Eastern Loudoun-
Including the cities of Washington, Baltimore, Bowie,
Suitland-Silver Hill, Clinton, College Park, Greenbelt, Laurel,
Camp Springs, Glen Burnie, Annapolis, Severn, South Gate,
Severna Park, Arnold, Odenton, St. Charles, Waldorf, Germantown,
Damascus, Bethesda, Rockville, Gaithersburg, Silver Spring,
Lisbon, Columbia, Ellicott City, Dale City, Manassas, Woodbridge,
Lake Ridge, Montclair, Reston, Herndon, Annandale, Centreville,
Chantilly, McLean, Franconia, Arlington, Alexandria, Falmouth,
Dahlgren, Warrenton, Turnbull, Purcellville, Leesburg, Ashburn,
and Sterling
627 PM EST Thu Dec 14 2017

...POTENTIAL WINTER COMMUTING HAZARD FOR THE BALTIMORE /
WASHINGTON METRO AREAS FRIDAY AFTERNOON...

There is a potential for hazardous commuting conditions for the
Friday afternoon commute. Light snow (with potential large impact
due to sub-freezing road temperatures) is POSSIBLE between 1pm
and 5pm Friday afternoon. There is a 50 percent chance of snow for
Washington and Baltimore. If there is accumulation, it is
expected to be less than an inch.

If this threat of light snow on frigid roads does materialize
Friday afternoon, the Friday afternoon rush-hour could quickly
turn icy on untreated road surfaces. This could lead to hazardous
traveling conditions, multiple accidents, and extensive delays.

If you plan on commuting Friday afternoon, be aware of the
POSSIBILITY of travel disruptions and icy roads. Plan ahead by
allowing for extra travel time, and consider using public
transportation and telework options.

Stay tuned for updates on this potential winter weather episode.

[CAPE]

Mount Holly's take from their late afternoon AFD-

Large-scale lift in the left-exit region of the upper-level jet
streak and in WAA/southwesterly flow ahead of the trough will likely
lead to the development of light precipitation during the afternoon
over coastal plain and possibly back into the I-95 corridor. Given
the trends seen in today`s guidance, PoPs were increased to chance
for the I-95 corridor and to likely for Delmarva and southern NJ by
late afternoon. Although temperatures in the coastal plain may be in
the mid to upper 30s early in the afternoon, evaporative cooling
should bring them down to freezing as precip arrives. Accordingly,
ptype looks to be primarily snow for this event with the possibility
of a brief rain/snow mix at the onset near the coast.

The progressive pattern makes this a short-duration event, limiting
the risk for more substantial snowfall accumulations. Forecast
amounts that went out with the afternoon forecast package are 1" or
less for Delmarva and southern New Jersey. There is some support for
mesoscale banding (through snow bands would be much more transitory
than what we saw with the December 8-9 event) that would lead to
locally higher amounts with frontogenesis potentially occurring on
the northwestern side of the developing surface low. For the I-95
corridor, kept snowfall accumulations out of the forecast for now
with them predicted to be on the north/western fringe of the
organized lift and precipitation shield. We may need to expand light
accumulations a bit farther back to the north/west if trends
continue this way.

[pasnownut]

0z NAM's r trolling hard for a little more love from above.  No mucho, but flakes likely will be flying for 5 0 gotta go time tomorrow.

nice start to the weekend if so.

Nut

[yoda]

00z NAM decent for a 3-5 hr snowfall across the region... 1 inch or so near DC and maybe up to 2" in NE MD

[NorthArlington101]

3k is in.

[Kleimax]

Every single possible event this year has turned in our favor, amazing! Hopefully we can keep this up all winter!!!

[AfewUniversesBelowNormal]

Maybe it will trend toward a 3-4" event. position of low pressure is perfect for rapid deepening. 

[yoda]

5 minutes ago, StormchaserChuck said:

Maybe it will trend toward a 3-4" event. position of low pressure is perfect for rapid deepening. 

Lol no

[Cobalt]

Kuchera Ratio is pretty good as well during the peak snowfall

[AfewUniversesBelowNormal]

Maybe these happened many times in 02-03 and 04-05, anyway they usually keep trending stronger up to the event. 

[yoda]

Area Forecast Discussion...UPDATED
National Weather Service Baltimore MD/Washington DC
929 PM EST Thu Dec 14 2017

.SYNOPSIS...
High pressure will build overhead through tonight. Low pressure
will develop along the North Carolina coast Friday and move out
to sea Friday night. High pressure will return for Saturday
before weak low pressure impacts the area early next week.

&&

.NEAR TERM /THROUGH FRIDAY/...

Plenty of high clouds tonight tonight in response to
strengthening jet max and low pres approaching from the
southwest. Recent model trends have shown a little bit more QPF
along the western shore of the Chesapeake Bay and westward
extent of precip tomorrow afternoon resulting in a little bit
of snow to the VA portion of the Capital Beltway. A 3-hr period
of potential light snow accumulation is possible mainly between
18Z-21Z. The NAM and Canadian hi-Res remain on the snowier side
of the guidance while the Euro and latest GFS on the drier
side. Looks like between a quarter to half inch of snow could
accumulate along and east of I-95 based on the Euro and GFS QPF
using 13 to 1 SLRs. On the worst case scenario, up to 1.5 inches
could accumulate using the less reliable NAM and Canadian hi-
res models.

[Scraff]

16 minutes ago, StormchaserChuck said:

Maybe these happened many times in 02-03 and 04-05, anyway they usually keep trending stronger up to the event.