Winter Storm 1/6 - 1/8, 2017

[DopplerWx]

Nearly 10-12" on a line from upstate sc to se va as the storms ends. Beautiful run.

[Timothy Clyde]

EURO jackpot Raleigh east. Less in the MTNS.

[griteater]

1 minute ago, Wow said:

Yeah a bit... i'd also bet on some additional strengthening of the s/w the next few runs

Yes agree on the s/w strengthening closer to go time....just want to see this thing stay south now....warm SST's in gulf...fireworks would go off

[SN_Lover]

Note: all winter p-types as sn. 

[griteater]

2 minutes ago, J.C. said:

They way you guys are talking the Euro is caving to the GFS more than the latter...

At 500mb, they've converged closer together....like franklinwx mentioned...he thought we would get a blend...good call right now

[griteater]

Where is Cold Rain?....we have snow on the Euro before 1:30.  He sleeps too much 

[LovingGulfLows]

Hmmm Euro not as robust for the western portions of the region when it comes to frozen precip as the CMC was.

[Jonathan]

Just now, LovingGulfLows said:

Hmmm Euro not as robust for the western portions of the region when it comes to frozen precip as the CMC was.

Hopefully we can get those warm gulf waters to make this baby go boom. That'd expand the precip shield and maybe even nudge it NW a tick.

[NCSNOW]

16 inch totals northern coastal plain. Looks very Jan 2000ish with timing placement and axis of precip. 

Ukie wasn't lieing

[Tyler Penland]

5 minutes ago, LovingGulfLows said:

Hmmm Euro not as robust for the western portions of the region when it comes to frozen precip as the CMC was.

Ratios would make up for it, no doubt. Waiting to see what eurowx spits out but last nights 0z had 13-15:1 ratios across parts of WNC.

[JoshM]

Just now, griteater said:

Where is Cold Rain....we have snow on the Euro before 1:30.  He sleeps too much 

He's probably got whiplash from this back and forth from this relay race the models are starting.

BTW, I don't like the looks of the HP's, no Banana high like the GFS was showing at 12z. Temps look solid tho.

[LovingGulfLows]

1 minute ago, Tyler Penland said:

Ratios would make up for it, no doubt. Waiting to see what eurowx spits out but last nights 0z had 13-15:1 ratios across parts of WNC.

 

Referring to GA, Alabama, and W TN, but the amounts are lackluster for NC mountains as well.

[Met1985]

4 minutes ago, Tyler Penland said:

Ratios would make up for it, no doubt. Waiting to see what eurowx spits out but last nights 0z had 13-15:1 ratios across parts of WNC.

Not a bad run for us Tyler considering what the euro showed earlier. Remember this is not set in stone.  Could trend better or worst for us.

[HWY316wx]

Just now, LovingGulfLows said:

 

Referring to GA, Alabama, and W TN, but the amounts are lackluster for NC mountains as well.

I still think this thing will come West and North but I could be wrong.  I personally want the Westward trend.  At this point I will take it and like it though.

[Met1985]

2 minutes ago, Tyler Penland said:

Oh yeah I'd take that and run with it. Precip probably underdone with upslope and good ratios to boot. Perfect for my location right on the top edge of the SE escarpment. 

Yeah not bad at all. Maybe 3 to 6, 4 to 8 inches that run. I think we trend better. We do very well in these type events. We will luck out somehow.

[Orangeburgwx]

I don't know if this helps my area any but....

[packbacker]

2 minutes ago, Orangeburgwx said:

I don't know if this helps my area any but....

I am sure many folks will be rooting for a full phase next couple of days.   It could happen and it may be a blessing the Greenland block is gone. 

[Tyler Penland]

6 minutes ago, Met1985 said:

Yeah not bad at all. May 3 to 6, 4 to 8 inches that run. I think we trend better. We do very well in these type events. We will luck out somehow.

Looks like eurowx going 15:1 this time with 6-8" around Boone. 7.2" for Boone specifically. I'll take it. 1/5 of the way to the yearly average with that ha.

[griteater]

[LovingGulfLows]

Wonder why the Euro isn't as cold aloft as the other models....at least for Atlanta, much of the problem seems to be rain to start. Would be higher totals if it were all snow.

[griteater]

Canadian Ensemble mean was colder than the operational run

[Cary_Snow95]

6 minutes ago, griteater said:

This most likely wouldn't turn to rain at the end as it pulls away like it shows right? I thought cold air pulled in as a LP departs

[griteater]

1 minute ago, Cary_Snow95 said:

This most likely wouldn't turn to rain at the end as it pulls away like it shows right? I thought cold air pulled in as a LP departs

Correct, should stay as snow.  Guessing that model is picking up on it being middle of the day and at this time range has sfc temps too high there.

[CaryWx]

She's a beaut Clark!  Hope the ensembles support it

[griteater]

1 minute ago, griteater said:

Correct, should stay as snow.  Guessing that model is picking up on it being middle of the day and at this time range has sfc temps too high there.

I don't know where it's getting that from actually because sfc and 850 temps are below freezing thru the day....and sfc and 850 low tracks would be to the SE of the snow line

[Cary_Snow95]

1 minute ago, griteater said:

I don't know where it's getting that from actually because sfc and 850 temps are below freezing thru the day....and sfc and 850 low tracks would be to the SE of the snow line

Well I know Ryan recently added in these p-types so probably just a bug of some sort

[nchighcountrywx]

WPC 1:57am Update 

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
157 AM EST TUE JAN 03 2017

VALID 12Z FRI JAN 06 2017 - 12Z TUE JAN 10 2017

...MULTI-DAY HEAVY PRECIPITATION EVENT LIKELY ACROSS
NORTHERN/CENTRAL CA WITH IMPRESSIVE ATMOSPHERIC RIVER SETUP...

...PATTERN OVERVIEW/GUIDANCE ASSESSMENT/PREFERENCES...

THE LARGE-SCALE PATTERN ACROSS THE NORTHERN HEMISPHERE WILL
FEATURE HIGH LATITUDE BLOCKING OVER AK WHICH WILL CONTINUE TO
ALLOW FOR MEANDERING CLOSED LOWS TO INHABIT THE EASTERN PACIFIC.
TO THE EAST OF THIS BLOCKING REGIME...SPLIT FLOW WILL BE IN PLAY
WITH BROAD CYCLONIC FLOW ANCHORING MUCH OF CENTRAL/EASTERN NORTH
AMERICA. WITHIN THE SOUTHERN STREAM...A FORMER CUT-OFF LOW OVER
THE PACIFIC NORTHWEST SHOULD LIKELY BE IN THE PROCESS OF BECOMING
ABSORBED BY THE LONGWAVE TROUGH ACROSS THE CENTRAL U.S. ON FRIDAY.
HOWEVER...THE GFS HAS REPEATEDLY BEEN SLOWER ALLOWING FOR MORE OF
A SEPARATION WHICH LEADS TO A GREATER DEAL OF AMPLIFICATION
DOWNSTREAM ACROSS THE SOUTHERN PLAINS/MID-SOUTH REGION. AFTER
LOOKING AT THE 00Z GFS...THERE HAS BEEN A TREND TO BE FLATTER WITH
THE ATTENDANT SURFACE WAVE BEING WELL SOUTH TOWARD THE
SOUTHEASTERN U.S. RELATIVE TO THE PREVIOUS WRAPPED-UP COASTAL LOW
IT WAS FORECASTING. IT DOES STILL REMAIN WITHIN THE REALM OF
POSSIBILITIES AS THE 00Z UKMET LOOKS MORE LIKE THE FORMER GFS RUNS
WITH A 983-MB CYCLONE OFF OF CAPE COD MA BY 08/1200Z. GIVEN THE
CONTINUED DIFFERENCES IN HANDLING THIS FEATURE DATING BACK TO
PREVIOUS SHIFTS...IT IS STILL WORTH MONITORING. THE GOAL IN THE
EARLIER PACKAGE WAS TO UTILIZE A MORE ENSEMBLE BASED APPROACH WITH
ONLY 20 PERCENT OF DAYS 3 THROUGH 5 BEING COMPROMISED OF THE 18Z
GFS/12Z GFS-PARALLEL TO ACCOUNT FOR A MORE AGGRESSIVE SCENARIO.

AS THE NEGATIVE HEIGHT ANOMALY BEGINS TO DOMINATE THE EASTERN
SEABOARD THIS WEEKEND...A SEPARATE/PERSISTENT REGION OF TROUGHING
WILL AFFECT THE EASTERN PACIFIC INTO THE WEST COAST FOR MUCH OF
THE PERIOD. THIS WILL RESULT IN AN EXTENDED PERIOD OF WET
CONDITIONS ACROSS THE WEST COAST...PARTICULARLY OVER NORTHERN CA
WHERE SOME SOLUTIONS ARE FORECASTING 5-DAY AMOUNTS WHICH COULD BE
MEASURED IN FEET ACROSS THE SIERRA NEVADA RANGE. REGARDLESS OF
MODEL CHOICE...ALL SOLUTIONS FAVOR THE AFOREMENTIONED REX BLOCK
EXTENDING FROM AK DOWN INTO THE EASTERN PACIFIC. AT THE START OF
THE PERIOD...06/1200Z...THE POSITIVELY-TILTED TROUGH SHOULD BE
PEELING DOWN THE BRITISH COLUMBIA COAST WHILE STRENGTHENING AS IT
SWINGS SOUTHWESTWARD BACK TOWARD 130W. PERSISTENT SOUTHWESTERLY
FLOW INTO THE WEST COAST WILL BE ACCOMPANIED BY AN IMPRESSIVE
ATMOSPHERIC RIVER SETUP. RECENT GFS SOLUTIONS SHOW INTEGRATED
VAPOR TRANSPORT VALUES APPROACHING 1000 KG/M/S DURING THE EVENT
WITH THE MOISTURE PLUME EXTENDING WELL BACK INTO THE SUBTROPICAL
PACIFIC. COMPARED TO A 1979-2009 CLIMATOLOGY ON THE WESTERN REGION
SITUATIONAL AWARENESS TABLE PAGE...THIS COULD BE 4 TO 5
STANDARDIZED ANOMALIES ABOVE AVERAGE. OVERALL...GIVEN THE
REASONABLE LARGE-SCALE AGREEMENT...WENT WITH A THREE-WAY BLEND OF
ENSEMBLE MEANS...18Z GEFS/12Z ECMWF/12Z NAEFS...MAINLY TO ACCOUNT
FOR DIFFERENCES FARTHER DOWNSTREAM WITHIN THE AMPLIFIED
CENTRAL/EASTERN U.S. FLOW.


...WEATHER HIGHLIGHTS/THREATS...

ON FRIDAY/SATURDAY...WELL BELOW NORMAL TEMPERATURES SHOULD INHABIT
A VAST MAJORITY OF THE COUNTRY GIVEN DEEP CYCLONIC FLOW IN PLACE.
FORECAST ANOMALIES ARE EXPECTED TO RANGE FROM 10 TO 20 DEGREES
BELOW NORMAL BEFORE CONDITIONS REBOUND AS HEIGHTS BUILD ACROSS THE
CENTRAL TO EASTERN U.S. IN FACT...BY MONDAY..HIGH TEMPERATURES MAY
BE 10 TO 15 DEGREES ABOVE NORMAL FROM THE INTERMOUNTAIN WEST TO
THE HIGH PLAINS WHILE CONTINUING TO EXPAND EASTWARD IN TIME.

GIVEN THE COMBINATION OF DEEP UPPER TROUGHING AND A QUASI-ACTIVE
SOUTHERN STREAM...THERE REMAINS A THREAT FOR WINTRY PRECIPITATION
SOMEWHERE ACROSS THE EASTERN U.S. DEPENDING ON THE FATE OF THAT
NEBULOUS SHORTWAVE MOVING OUT OF THE HIGH PLAINS. THERE ARE PLENTY
OF POSSIBLE SOLUTIONS AT HAND WHICH WOULD LEAD TO AN ARRAY OF
SENSIBLE WEATHER IMPACTS. AND AS MENTIONED EARLIER...EXTREMELY WET
CONDITIONS WILL AFFECT THE WEST COAST...PARTICULARLY
NORTHERN/CENTRAL CA. THE AMOUNT OF PRECIPITATION SUGGESTED IN THE
GUIDANCE COULD EASILY LEAD TO NUMEROUS HYDROLOGIC IMPACTS WHICH
WOULD INCLUDE MUDSLIDES...DEBRIS FLOWS...ETC. WHILE THE PATTERN IS
RATHER MILD...EXPECT HEAVY SNOW TO AFFECT THE HIGHER
ELEVATIONS...ESPECIALLY THE SIERRA.


RUBIN-OSTER

 

[ncskywarn]

Morning National Weather Service AFD from Raleigh.

.LONG TERM As of 305 AM Tuesday...

Friday Night and Saturday: The models are in better agreement and thus there is an increase in forecast confidence with respect to the overall pattern for this part of the period. However, there are still differences in timing between the GFS and ECMWF. Generally, a shortwave trough will move through the Midwest Friday night and into the Carolinas on Saturday. Meanwhile, southwest flow aloft will result in good moisture transport from the Gulf. Also, a surface low will develop over the Gulf and move NE through FL and along the Carolina coast. There is more than sufficient moisture and forcing mechanisms to result in precipitation during this period, much of which will be snow or a rain/snow mix transitioning to all snow
(based on the current temperature forecast). Overnight lows will be in the 20s and highs will be in the mid to upper 30s. This period will be closely monitored over the next several days, as it provides the best chance for impactful winter weather.

[msuwx]

2 hours ago, griteater said:

I don't know where it's getting that from actually because sfc and 850 temps are below freezing thru the day....and sfc and 850 low tracks would be to the SE of the snow line

Possibly loss of lift/ moisture in the snow growth region.... wouldn't be rain though, would be freezing drizzle/ rain with SFC temps well below freezing. 

[WNC_Fort]

6z GFS low is further south in the Gulf. Precipitation has trouble making it into the western and Northern tiers of North Carolina. Good snow for the Deep South.