No Change From Last Evening

The high resolution modeling is seeing no real differences from late last evening to this early Friday morning.  Below is the total event from the storm in terms of accumulated precipitation, the bulk of which will fall as snow around Harrisburg.  Again, some pinging sleet pellets will greet your awakening Saturday morning, but a general 15:1 snowfall should be/have fallen during the very early part of Saturday.  The map shows a general 5-7" coverage around KMDT.  Note the enhancement over the mountains of western MD and the Laurel Highlands of PA.

I will show this...one of my favorite quick hitters for info; the ensemble plumes.  It is interesting to note that the snow/ice line will be very close to our location.  To be sure, temps will remain below freezing at least until noon Saturday, so plain rain, in my opinion, is out of the question.  It is just how much freezing rain and sleet will mix in at KMDT.  I have both Lancaster's and Harrisburg's plumes from the GFS ensembles.  Note the greater number of blue lines at Harrisburg indicating a "snowier" event whereas the increased number of red lines indicating a greater threat of ice in the southern part of York and Lancaster Counties.

Here is KMDT...

And here is KLNS...

In any case, just be cautious tomorrow morning on any travels.  Conditions will improve by afternoon.  I will leave y'all with this from NASA news; a short 3 minute clip about some things you read on here from time to time.  Although somewhat biased warm (you must remember where one gets their funding!), I feel it is done rather objectively to discuss the CYCLICAL nature of climate on this wonderful earth!

Have a great week's end!

Smitty

AA:  A nice moderate early weekend winter event (mostly snow) with a general 4-5" snowfall....some places your way will top 6"!

Saturday Morning Snow Update

The 00Z NAM just came in and I really don't have too many changes.  What will this storm be?  Mostly snow with sleet pings near the end Saturday morning...finally tapering off to freezing drizzle by noon Saturday.  Temps during the snow part of the storm will be in the low 20s in the pre-dawn hours of Saturday.  The max temp will struggle to get to 35ºF Saturday afternoon during clean-up.  How much?  It now appears as if 3-5" is a conservative prediction.  I believe a few 6"+ will be reported in the Harrisburg area.  It is most certainly a PLOWABLE storm and by NO MEANS is this a crippling storm!  Saturday morning should a "Go-Slow" and not a "Don't-Go" kind of morning.  Or better yet, just brew a few extra cups of your favorite potation (don't make it potent before noon!...but it will be afternoon somewhere so I am told) and enjoy the winter scene which we've sorely lacked this winter!  Here is the NAM's total snow amounts when all is said and done.

I know there is no scale...it is off of my screen-shot...the dark blue is ~5", the purples ~8".  This will be a healthy snow event...no doubt!  Note once the wave of low pressure is able to access Atlantic moisture, snowfall increases towards the coast...although some of that will fall in the form of plain rain on the coastal plain.

The heaviest snow will fall in the pre-dawn hours as shown below...the map below is for the 3 hrs ending at 4am...

And the temps at 7 am sunrise temps...clearly, the cold air damming signature is present at the surface of the earth!

The snow and light freezing drizzle will pull away by noon as shown here...this is for the 3 hours ending at 1 pm...

Clean off surfaces you want cleared as Sunday morning temps will be very cold with the fresh snowfall.  As we all know, cold breeds more just like winning breeds more winning!  Temps will bottom in the low teens Sunday morning under a clear sky and light winds.

But by Sunday afternoon, the winds will begin to advect warmer air from the south and west so by Monday, we are looking at temps to be nearly 10 above normal...or max temps in the 40s!  Again, look up in AK...when our 49th state is cold, we are NOT!

Most of next week will feature above normal temps...but I show you this as a tease for later posts...look at what is lurking for February!  We might just have an American Pie kinda February!  Nothing like watching the Super Bowl when the temps outside are brutally cold!  The modeling is hinting at it...

For those of you not familiar with Don McLean reference above...sit back and enjoy this throwback!

Have a great weekend...and enjoy this snowfall...the only real snowfall for this January it now appears!

Smitty

AA:  Snow upon waking Saturday; all but a distant memory by Tuesday/Wednesday!  Much above normal by end of next week...again!

Predict the High; Predict the Snow

This was a lesson learned years ago about the synoptics of a wx map in the northeastern USA.  If a large Arctic High Pressure system ridges north across southern O Canada and new England, then overrunning precip in the winter months will often fall in the form of snow if taking the "proper" track.  Well, just one graphic in this quick update and that is from our modelers to the north who should have a fair understanding of Arctic cold!  The Canadian model keeps our entire precip event in the form of the fluffy white stuff and the closest any icing is in nearer the Mason-Dixon Line.  It is a trend that I have been monitoring today as the all of the models have been trending COLDER for this winter wx event.  Here is the 7 am map from the Canadian model for this Saturday morning...

That 1029 mb High over Quebec is supporting sub-zero temps and extremely dry air.  A strong cold air damming wedge will be funneled down east of the mountains so if any precip does changeover, it now appears that sleet and frz rain will be the predominant types and not plain rain.  Roads will improve later Saturday as the storm pulls off to the east.  The snow should start around midnight Friday and last for ~12 hrs; the heaviest falling between 5 am-9 am Saturday morning.
Enjoy your Thursday evening.....

Smitty

AA:  Looking at our 1st snow of the true winter season this Saturday morning...

First January "Real" Snow

Our 1st "real" snow will be experienced this Friday overnight into early Saturday morning.  It's now beginning to appear that the precip will begin as snow and continue as snow until the warm air aloft gets pulled over the cold surface temps which will create a period of sleet/freezing rain prior to the precip departing.  Here is the GFS accumulated snowfall map for Saturday morning...

It appears that we will get about a 2-4" snowfall prior to the changeover Saturday mid-morning.  My fear is that the low level cold air will hang tough creating a longer period of frz rain as the storm departs.  This "storm" will not be a classic winter storm for us in any sense...but it is one of these events that traverse the entire country.  You can clearly see its path across the northern tier of the US above.  The little bit of flurries we will see Thursday evening is associated with a weak clipper that will bring in colder air to set the stage for our "moderate" event.  Saturday morning will be a GO SLOW and not a DON'T GO morning...Below, the GFS has the rain-snow line (dark black line) right over us during Saturday morning...

OK...gotta go....have a good Thursday!

Smitty

AA:  Brief flurry Thursday evening sets the stage for Saturday early morning snow event changing to ice and maybe just end as plain ol' rain!  Get up here for lunch today!

A Snowless January

, Well, the possibility exists!  In fact, it is a very real possibility as I work my way through the medium range modeling.  However, prior to doing so, there is one very prominent proverbial "fly in the ointment" for this Friday night into Saturday morning time frame.  The GFS and to a minor extent, the ECMWF, create a small wave of low pressure that will erode the cold air that will be in place later this week.  The GFS keeps the wave to our south; however, as many of you are aware, the GFS will correct a bit to the north and if modeled correctly, we could see ~0.5" of liquid falling all as snow.  This would be a small plowable storm for the beginning of our upcoming weekend.  However, if you didn't feel like plowing or shoveling, you would not need to do so as mother nature thanks to the +NAO and +AO will melt away any evidence of winter's presence by early next week.  Here is the potential winter wx event for this Friday night into early Saturday morning...

One thing to note on the above map is that the Cascades will be getting hammered with snowfall this week and into next week as well.  The Pac NW and the CA Sierra do need to get their "money in the bank" snowfall when the getting is good!  Presently, the Sierra, like all of the US is hurting for snow pack.

Here is the snow cover for the entire US...This is much greater coverage than last Friday as the lake effect machine kicked in over the weekend.  If I post later this week, we will note how much the snow will have retreated by this upcoming weekend as the snow depth is minimal in IN, OH, IL, and western PA.

But next week and the week after look to be warming considerably after this week.  Here is the GFS ensembles for North America in terms of probability of above normal warmth for the upcoming period 2 weeks hence.

As long as there is a strong AK temp minima, there will be no way to get cold and snow to the eastern part of North America, especially here in the Mid Atlantic!  That map above is simply uuuuugh for any winter wx enthusiasts here in our neck of the woods!  The map below shows the 7 day running mean of temps for the period ending one week from today.  Look at that 20+ degree anomaly in the deep south!  Now this is an average of the daily means over a 7 day period ending next Monday. 

Look at the same stat for the 7 day period ending next Thursday, the 26th of Jan!  Wow!  The sled dogs in MN won't know what in the world is going on!  They'll probably have a doggie convention and blame the anomalous warmth on global warming!  On thing for certain; this type of warmth in January will not help the depressed Nat Gas prices here in the states.  With that in mind, one better try to make some money in the oil and oil services as opposed to companies with large exposure to strictly natural gas.  Remember my disclaimer....thank you!

In closing, what a sports weekend for local high school athletes and some interesting professional results as well!   The CD wrestling team put on a clinic in their own duals.  In doing so, this A1 program has earned the state record for consecutive wins in dual matches, now at 82 and counting.  It is a real pleasure to witness these wrestlers' endeavors; some with technical skill, some with brute strength, some with shear heart...all with desire!  Then, at the Villa BB tourney at CDHS, the nightcap proved just how dominating a player Devon Thomas can be.  It certainly helps that he has an incredibly strong supporting cast, but when he focuses strictly on the game and ONLY THE GAME, he is capable of single handily taking control of a high school game with his size and athleticism.  If he continues to maintain focus, the CD boys will be a tough "out" in any tourney they are "in"!  And in the professional ranks, the 49ers-Saints game was certainly entertaining, but the football school was taught by the NY Giants!  A power running game and a staunch defense proved too much for the Pack from GB!  Being an Eagles fan, it is difficult to root for the Giants; however, I love their style of physical football.  Control the game by running the rock and being fundamentally sound defensively!  These ingredients almost always win at ALL levels of football!  I do believe that the Super bowl will be the 49ers-Giants match up next weekend.  It should be a good defensive heavyweight game.  I like the Giants for what it is worth at this point....a cold rain looks to be in the cards for SF next weekend...

Take the Giants and Under in the potential quagmire...

Have a good week!

Smitty

AA:  After a rainy Tuesday, temps will again be January-like.  Then a major warm up for the next 2 weeks.  Could have a little snow Friday night into Saturday, but all will be melted once again by early next week.  Congrats on your efforts in the CD wrestling program!  I like the Giants in the NFC Championship game....you?

Arctic Front To Pass Friday Early Morning

Just a very brief post to alert many of you that a very real shot of Arctic air will be invading PA on Friday!  With it, a relatively rare occurrence for us living here in the sub-tropics, will be an area of enhanced precip falling primarily in the for of snow, and doing so very quickly, possibly accompanied by thunder and lightning, followed by a Flash Freeze making for a real "fun" commute!

Now let me get through all of this.....first the precip Wednesday night into Thursday will be rain.  And we may see ~1.25" or slightly more when all is said and done by Thursday morning.  Take a look at the plumes from the Short Range Ensembles latest runs.  I block highlighted the 2 areas of precip...the one in red is Wed night; the purple is Friday early am.

Once the rain ends Thursday morning, clearing skies and mild temps will follow to make Thursday afternoon relatively benign.  Temps should reach the low 50s by Thursday at 3 pm.  But that sets the stage for a nasty cold frontal passage for overnight into early Friday morning where thunder-snows I believe a be a real possibility!  Here is the front as depicted by the modeled winds for 4 am Friday morning.

And as seen by the surface temps...note that overnight we are still way above freezing.  This is what will create the great instability with the rapid advancement of the Arctic air to the west.  A 30ºF difference will be seen over a 100 mile E-W distance!  The bright purple line is the freezing line.  When the front passes, it will likely start as rain, but QUICKLY change to snow and then FLASH FREEZE for the Friday am commute!  Be aware of this possibility!

Here is the larger scale global model GFS and its take on the synoptics for Friday morning...

If the closed 500 mb low passes just a bit further south, then we are looking at a 1-3" frontal passage snowfall Friday morning followed by a blustery and very cold Friday and Saturday!

OK....enough now....gotta go!  But it is something to talk about for the last few days of the PA Farm Show.  How could we get through this week without even a little winter wx!

Have a good Wednesday...

Smitty

AA::  Rainy Wed night into Thursday am, then a nice Thursday pm, arctic front passes pre-dawn Friday with some rain and mostly snow ~1" or so...and then very cold!

Christmas Light Takedown Warning

Hey, the NWS has a wx watch and warning for just about every type of wx event...so I thought I'd join the fun and games and issue an "Outside Christmas Decoration Removal Warning" for today, Saturday, as the high temps will once again try to achieve 20ºF above normal!  Below is the actual output from the NAM for the grid of max temps across PA for this afternoon.  Mid 50s are a sure bet...my take is the model is still just a bit underdone; not to the extent of yesterday where the modeling was busting by 10ºF (48ºF forecast vs 58ºF actual!). So get out and enjoy today's mild wx under mostly sunny skies, but with an increasing SW wind.

And from what I can ascertain from the modeling, we will be experiencing a roller coaster ride of temps over the next 2 weeks.  Yes, we will see bouts of cold, but they will be interrupted with anomalous warmth.  What I will do is show you the GFS' take on strictly the temps over the next 2 weeks in terms of deviations from normal or anomalies.  First, the initialization where we saw very real warmth Friday afternoon...much unlike the CD Rams field goal shooting Friday evening.  Just a few things to note...the complete lack of cold over the US and most of North America for that matter with the exception of AK.  The raw anomalies are +12ºC or ~+24ºF for most of PA!

Now for this Tuesday pm...again a ridge pops in the east!

This is ahead of a storm that will move right up the Ohio River on Wednesday bring RAIN for midweek Farm Show attendees.  Once that storm passes, a strong cold front will briefly send PA back to reality as the temps are now shown for NEXT FRIDAY...or ~1 week from today...that is some serious chill for PA for Farm Show Friday!  Temps will remain in the 20s all day!  Note the persistent chill over AK!

That cold will all be a distant memory once MLK Day rolls around...note the cold now being displaced from AK!

And by 2 Fridays from now, that cold will have unleashed its fury across the lower 48...but then the cold builds back over AK and warmth returns to our heartland.

Finally, in 15 days, here is what the GFS believes to be happening with the North American temps...look at the expanse of warmth over the northeast US!  Even New England skiing will be experiencing a pathetic mid season ski season...icy conditions without the glorious powder "normal" temps usually allow for the part of the east to enjoy.

A roller coaster of  temps...when it gets cold, it will be cold as the air flow is cross-polar; note the flow from the Euro (left) for next Friday-Sat period.  That is a deep trough with its air originating in the Arctic...the GFS has more of a coast to coast cold pattern.  Regardless, it will not hold as I showed above as per the operational run of the GFS

I show here the AO and the NAO of the GFS and its ensembles members.  The bold blue line is the primary run of the modeling...it seems to be in a fair bit of disagreement with its ensemble members as seen here...the operational is clearly the outlier whereas the ensembles keep the AO negative!

The same is true for the NAO...the operational is heading waaay up in comparison to its ensembles...

So will the cold hold once it hits?  The ensembles say there is a better chance than the operational runs from the GFS; the operational is a roller coaster ride for temps over the next 2 weeks.  By the way, here is the amount of RAIN for the midweek period...looks like a solid 1-2" band of liquid sunshine from Dallas to Dubois.  Some of that precip may fall as sleet and frz rain at the onset in the mountains to our west, but at this point, I believe that nearly ALL of the precip at KMDT will be in the form of rain.

My advice...get a tall tropical drink and sit outside this afternoon (after removing your outside Christmas decorations) in a southern exposed area around your place and enjoy this classic.  Because, if you can't get to the tropics, surely the tropics have been trying to get to you!

Enjoy the week's end!

Smitty

AA:  Another mild day followed by a couple of weeks of roller coaster temps.  Wrestling tonight?