Sunday, January 23, 2011

Video Blog Discussion... Tuesday Trouble and Beyond

12:30 PM Monday Update... Thought I would update you on the situation Tuesday and beyond.  I still feel it's eastern Arkansas which stands the best chance for some rain changing to snow Tuesday afternoon and evening as the cold low moves overhead.  The GFS is even showing some accumulation over far eastern areas.  This model seems to be playing catch-up to all the other modeling out there so my question remains, how far west will this eventually end up?  Check out the latest version of our exclusive model "Futurecast".  Remember, this is only a model and not a forecast.  It's showing even more in the way of accumulation for the SE half of the state including Little Rock.  Am I buying it????  Not right now, but it got my attention for sure...

12Z Futurecast run from Monday

Now for an update on next weekend and beyond.  The Euro last night  brings the next batch of arctic air into the state Monday (Feb. 1st) with waves of moisture arriving from the southwest.  The late run of the GFS yesterday was not showing much in the way of precip. but now the new morning run is showing a set up more conducive to bringing in the moisture.  Still enough disagreement to keep this a low confidence forecast in this time range... stay tuned.

8:25 AM Monday Update... I decided not to start a new post so you can see the possibilities in the video blog discussion below.  Here we are just 24-36 hours away from this new storm deepening over the mid south and the models are not yet in agreement.  To me the question is how much of the precipitation shield works to the northwest and what's the temperature at the surface.  The UKMET, CMC, and the JMA all bring the precipitation further to the NW than the more widely used modeling GFS and NAM.  Even if the precip. works further to the NW Tuesday, surface temperatures could be too warm for anything but rainfall.  However, many of you know what a strong area of low pressure aloft can do.  There can be enough cooling to bring wintry precipitation to the ground and give forecasters a BIG headache.  Even the National Weather Service forecasts out of Little Rock and Memphis are accounting for at least a little frozen precipitation on the northern fringe, especially late Tuesday.  Even if nothing happens with this, I still find the entire situation amazing to watch considering the development of this storm is several hundred miles away from what the models were showing just a couple of days ago.

Now onto the remainder of the forecast.  The period Tuesday through Thursday still looks cool with temperatures running below average.  A new arctic boundary will make a dive towards Arkansas next weekend, BUT ahead of it, we could see some STRONG warming Friday.  We have been talking about this here on the blog for several days now.  The 00Z GFS is even taking temperatures into the 60s in Little Rock Friday. Now there are differences in the modeling as to how the next storm will unfold or will not unfold at all.

The GFS has an overpowering northwesterly wind flow which keeps the state dry and cold next week.  The Euro has a different scenario all together.  This model brings a strong area of low pressure into the southwestern United States and develops a southwesterly flow aloft.  This would significantly slow down the intrusion of any arctic air..HOWEVER, you must always remember, the shallow nature of dense, arctic air usually ends up further south than the data forecasts.  The Euro seems to want to eject pieces of energy in the southwesterly flow and bring precipitation chances into the state during the first couple of days of February.  So there are differences which is very typical in the long range.  While there will remain uncertainty, you can be certain we'll be here every step of the way to figure out mother nature's next move!!!!


6 comments:

Amy said...

Great post, Todd!! I so love your enthusiasm and excitement!!! You guys were silent all day yesterday, and then suddenly, last night...twitter went crazy as the models started trending west with the storm and it was "Weather Geek Heaven" for me!!! You know how you always say that in the long range the models can show these big storms..then back off...then bring them back again. Is this one of those cases?? It seems like I remember this pattern setting up a couple of weeks ago and seeing this moisture and cold air here about this time....and then it went away. I could be wrong...but you are so right...it is fascinating to watch all of this, not matter how it turns out!! Frankly, I'm cheering for a "Japanese Rising"!!! That model is due for a verification....just saying!! Anyway...thanks as always for making weather fun! Get rid of that cold and take care of yourself!!

Anonymous said...

the next 2 weeks looks very interesting in the way of winter weather. central and south Arkansas dont usually see this kind of pattern. maybe every fifteen to twenty years. it is nice to have it this way sometimes. i would love to see a big heavy snow that piles up inches per hour and it has been a while since we have seen great opportunities like this.

Anonymous said...

Looks like snowbird is right on the storm to far south for ark to get any snow . Start watching the euro any time now trending south with the system. That arctic air will be dense an we should be just very cold but dry. We have a chance to see low teens for lows in little rock and highs in little rock in the low 30s it should be sunny though but still cold.

Jason H said...

Seems like our best snow in Northern Arkansas always comes after the real COLD air has moved out, around the 2nd or 3rd week of February. It is so hard to get moisture up to Northern Arkansas with the kind of cold air that will be coming down by late weekend. I would just about, well I would put money on Northern Arkansas seein a good snow "4-8" anywhere from Feb 15th - March 7th. If it snows in that time frame, and it usally does, you can bet it will be big wet flakes. Severe weather season is creeping up on us. I need at least one big Winter event before that happens, is that too much ask?:-)

Jason H said...

Btw if we can get a little cold air sucked in tomorrow we could see some big flakes flying around along the Mississippi river. If it happens I am going with Helena 3-4 inches. It will have to snow it's butt off to get that with suface temps the way they air. Memphis may be the winner?

Anonymous said...

I'm curious about something. I noticed that the NWS in Little Rock has forcast a 60% Chance of rain on tuesday for Brinkley. Just a few miles due east, Wheatley has a forcast of 80% Rain/Snow from the NWS in Memphis with possible accumulations tuesday night of less than 1/2 inch. NWS Little Rock makes no mention of this. I've noticed before this difference in forcasts for areas in Arkansas covered by NWS Memphis. Is this just a difference in intepretation of the models? In general, the NWS Little Rock seems a little more "conservative" (if thats the right word) than either NWS Memphis or NWS Tulsa. Just wondering....I know, I know, I need to get a life.......


Susan.....

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