2008-09 Winter Expections For Delaware

Winter 2008-09 is upon us. I have taken a bit of time to create a quick roundup of discussions around winter forecasts that include expectations for Delaware. These discussions are done by both Professional and Amateur meteorologists and do vary in some regards. What I like best about them is how they support their forecasts with scientific data interpretations.

Winter 2008-09 Forecast Roundup:

Link to discussion thread containing various forecasts.

Forecast A (Amatuer)
Forecast B (Professional)
Forecast C (Professional)
Forecast D (Amateur)
Forecast E (Amateur)
Forecast F (Amateur)
Forecast G (Professional)
Forecast H (Amateur)
Forecast I (Amateur)
Forecast J (Professional)
Forecast K (Amateur)
Forecast L (Professional)

One of the more common factors in this forecasts and has a rather real impact for snow in Delaware is the NAO (North Atlantic Oscillation). Without getting in to a whole lot of science and ignoring other important factors, the NAO does a good job of telling what kind of pattern we will see. A positive NAO would result in a snow pattern setting up north of us. A negative NAO would result in a snow pattern setting up to the south or over us. The negative one is what would give us the greatest chance of snow. Many are expecting to see a negative NAO this year.

 

Snow Showers Likely Overnight Nov 17-18

What a great start to this years Winter season. It is looking more and more likely that we will be seeing some snow flakes fall from tonights clipper system. Further more, both the GFS and NAM are showing Delaware as the expected path for a transfer of energy from the clipper to a coastal low. This means that certain areas (hard to predict who) will see a few nice bands of snow from passing showers. It could also mean that some places may pick up close to an inch of snow tonight. Since temperates are expected to fall through Tuesday, most of us will hopefully wake up to a few flakes on the ground. Get those car windows ready and be prepared for the slow commute tommorow morning.

Here are a few model images of how the system is projected to cross Delaware:

NAM Model 11-18 Event

GFS Model 11-18 event

Chance for Snow Nov 18th

In case you have not noticed, the cold blast referenced earlier came through with all its expected cool air. Now, it looks like a a weak early season clipper will bring some extra energy through our area late on Nov 17 and throughout the day on Nov 18. Temps on the 18th will be hard pressed to break 40. During the same time, some moisture is expected to pass through the area. Snow showers are likely for the area, mainly in the morning of Nov 18. No accumulation is expected, but some places may see a dusting if a heavy band passes with one of the snow showers. One particular area of interest will be Southern Delaware where both the GFS and the NAM show a chance of abundant snow showers that could result in over an inch of accumulation.

Key Word = Seasonal

I am a getting a late start to this weeks thoughts due to an illness that I have picked up. Picked a good week to be limited in capacity as this week will be rather uneventful, although we may see another coastal low with some rain Thursday and Friday. I don’t expect it to be as wet as last weeks low was, which I think the GFS did a good job of predicting.

Last week we experienced the warmer side of “seasonal” and this week will experience the cooler side of “seasonal”. Looking down the road, the GFS shows a cold snap to start off next week and we will have to see how this cold front goes as we get closer, and more accurate, to the actual timing of the front.

As we approach the middle of the month, we will have to start looking at patters and trends that will impact our long range temperatures and precipitation. There is a lot of discussion going on right now that around how the second half of November will turn cold. Ruggie Weather has a great write up to discuss these thoughts.

A few images, late week coastal low and next weeks cold front.

Nov 4 – Election Day Weather Considerations

The GFS is still showing a rather significant rain event for the middle of the week. Although timing is never a precise science it looks like those who wait until the evening to get out and vote may be doing so in the rain.

The latest models show moderate rain starting between 2pm and 5pm on Election day. If the long lines predicted on the news come true, there could be quite a few people that may be stuck standing in the rain waiting for their turn to vote. So, try to get out in the morning to vote if you can help it.

As far as the storm in general, the GFS has outputs of just under an inch for the event, including a very rainy Wednesday. Looking beyond the rain, the cold air I discussed yesterday seems to have fizzled a bit but there are some indicators out there that are showing a strong chance that the second half of Nov will turn cold.

More to come..

Weekly Thoughts: Nov 2nd through Nov 8th

Ahh, its the first week of November. Time to start gearing up for the Winter season. As mentioned in an earlier post, I am going to start writing more frequently starting in November. Of course, the late cold snap to end October actually had me blowing the dust off the old model links in order to ensure that I didn’t miss the first shot at a little white stuff (false alarm). Anyways, heres my first writeup which is going to be strictly based from the GFS computer model.

Gotta love the indian summer that happens around this time of year, especially with it following that premature cold snap last week. This week is the exact flip flop of last weeks cold with temperatures hovering in the low 60’s all week.

Nov 4th through the 6th models are showing a rather significant rain event for our area that will be produced from a coastal low that, to my lay mans interpretation, stalls off the Delmarva peninsula. If any of the rain amounts hold to model projections, I would expect to see over an inch of precip in our area.

Looking farther out, we could see a cool down by the end of next weekend, and some even cooler temps are showing up around Nov 18th, but that is very unreliable and we will have to wait and see.

I am too tired to attach any pics to depict what I was looking at tonight. The only interesting thing to watch this week is to see how well the GFS tracks the rain event Tue-Thur.

Chance of Flurries on 10/29 ?!?

A nice coastal low that formed along the leading edge of the cold front I wrote about last week has produced a good amount of moisture. Now, as the system exits and a strong NW downflow from Canada enters we will have temperatures at the surface low enough that we may have a slight chance to see some flurries Wednesday morning.

In the NWS’s recent forecast discussion, they even mentioned a slight chance of snow showers in the south.

SOME SNOW SHOWERS WILL FALL ACROSS THE FAR NORTHERN AREAS DURING THE DAY WITH A MIX OF RAIN AND SNOW SHOWERS FARTHER SOUTH, BUT JUST A CHANCE.

Models indicate that conditions Wednesday morning could support some frozen precip in our area.

Late October Cool Down

As I was going through the site and updating the links I could not help but run through a few computer models. Low and behold the GFS computer model shows a nice cold snap coming down from Canada. Although it is not a real cold punch, in a winter weather sense, it will definitely feel cold since it will be the coldest it has been this season thus far. For those concerned about Halloween trick or treating, rest assured, it looks like temps will recover from this cool down before then.

Winter Blogging 2008-2009 Coming in November

Fall came late around here this year and it seems that I have not gotten the itch to start watching the forums, models, etc. But I still wanted to jump on and put a post out to anyone who was rooting around the site to see if it was going to push on this year. I have plans to begin my Winter blogging in Early November (unless something happens prior). Between now and then, I will try and get all the links, maps, models, etc updated for this year. Thanks.

Feb 20th – Alberta clipper to disrupt rush hour on Wednesday

Well it looks like the 2008 winter season will go down as the rush hour snow storm season. Yet again we are prepping for a clipper system to move through our region Wednesday morning and should have the roads messy by rush hour on Wednesday. Given last weeks ice storm scenario, get ready for a lot of car accidents and delays everywhere you go (especially in New Castle county).

Here are highlights of the NWS discussion on the system:

• THIS ALBERTA CLIPPER HAS THE POTENTIAL TO GIVE A GOOD PORTION OF THE CWA BETWEEN ONE AND TWO INCHES OF SNOW FROM ABOUT NOON WEDNESDAY INTO THE WEDNESDAY EVENING COMMUTE BEFORE IF MOVES RAPIDLY AWAY FROM THE COAST.

• BRIEF SNOW IN SOUTHERN DELAWARE

• RAIN/SNOW LINE IS EXPECTED TO MOVE NORTH DURING THE AFTERNOON HOURS TO PROVIDE RAIN IN SUSSEX DE

• MIXTURE OF RAIN/SNOW IN CENTRAL DELAWARE

• CURRENT THINKING IS THAT TEMPERATURES WILL STAY COLD ENOUGH TO ALLOW ALL SNOW IN CECIL AND NEW CASTLE COUNTIES

• THE SNOW IS EXPECTED TO BE FLUFFY GIVEN ALL THE COLD AIR IN PLACE

• SNOW IS EXPECTED TO MOVE OUT OF THE REGION AROUND OR JUST AFTER SUNSET.