Wednesday, 11:30 am.

So much going on, so little time. I deplore days like today when I've got a ton of thoughts on my mind, especially with regard to the weather! How do I get them all out in a timely, readable, understandable and relatable way? Sigh....

Well, here goes. First up is the remains of Ida. No longer considered a tropical entity, the remnants of Ida are far from raising a ruckus. Sometimes here at AccuWeather.com, we've gone to calling these storms once inland and no longer considered tropical a 'tropical rainstorm'. That is still somewhat misleading, in my opinion, since the storm isn't tropical at its core any longer, but it has the advantages of still calling attention to a storm that had tropical origins and is still going to cause a lot of problems with rain and flooding.

There are two main tests to determine if a storm is tropical or not. One is the thermal structure. In tropical systems, the temperature at a given height level above the surface INCREASES as you from the exterior of the storm to the interior. This makes them a 'warm core' storm. In extratropical cyclones, the opposite as true. As you go from the exterior of the storm to its center, the temperature at a given altitude DECREASES, making it a cold core storm. The other test involves the wind field. In tropical cyclones, the strongest winds are very much concentrated near the center of the storm, and they decrease pretty quickly the farther away from the center you go. In contrast, with extratropical cyclones, the strongest winds are pretty much always well removed from the center and are quite often spread out over a large area. This is also tied directly to the position of any surface anticyclone. The difference in pressure between the two, or pressure gradient, pretty much dictates the strength of the wind, and since that pressure gradient tends to be fairly uniform until near the center of the high or the storm, the winds are spread out over a far greater area.

As we look at Ida's remains today, it clearly fails the two tests above. Looking at the 12z 700mb and 850 charts, temperatures near and just northwest of the storm center were lower than to the east and south at the same altitude. And the strongest winds aren't anywhere close to the low-level center.

To be truthful, the pressure will fall in this storm this afternoon and tonight. Part of that is directly tied to the fact it will be back out over the semi-tropical waters of the Gulf Stream just off the Southeast coast. However, upon closer inspection, only right at the core the Gulf Stream are sea surface temperatures at or a little above 80, the threshold that is commonly considered the 'break even' point for tropical development or not. Most of the SST's are in the middle 70s. That's great to add some juice to any storm, but not enough to give that shot of adrenaline to a tropical system.

Aside from the semantics of the type of storm it is, the main worry is about the weather, and it's no picnic across the Carolinas up to the southern end of New Jersey right now. Rain is a huge problem, obviously, as much of the area from the Florida Panhandle and Alabama up to North Carolina has picked up anywhere from 3 to 6 inches of rain, with some isolated higher amounts. That is causing extensive flooding, and the area from eastern South Carolina up to Delaware and even parts of South Jersey could be facing similar rain amounts before this nightmare comes to an end.

The wind is the other issue, as some of the Coast Guard stations, other coastal sites and offshore buoys are reporting sustained winds of 20 to 30 mph with gusts nearing 40 mph, and it will get worse this afternoon and tonight into tomorrow before the storm finally begins to unravel on Friday. Even then, the east to northeast winds won't exactly quit from the Outer Banks northward, so the non-stop battering will continue taking is toll on the entire coastline with extensive flooding and beach erosion and very high surf. In short, no day at the beach.

I'm still concerned that throwing all this moisture across the Carolinas and Virginia back up against the Appalachians will eventually allow some of the moisture to flow northward into central and northeastern Pennsylvania and points farther north and east, whereas now it is limited to southeasternmost sections of Pennsylvania and South Jersey. The rain amounts would pale in comparison, but you'd go from some sunshine with temperatures still a little on the high side of average to cloudy and potentially wet in short order on Friday and Friday night. This sets us up for a cloudy, wet start to the weekend in much of the Northeast.

The good news? The air mass is cooling now where it's raining, but it can't get much cooler as temperatures have pretty much crashed to the wet bulb temperature in these areas. The air to the north won't get any colder or drier, so as you continue bringing moisture in from off the Atlantic, which is still relatively warm, by the way, the air mass will moderate, so temperatures will moderate upward Friday into the weekend.

Then, as an upper-level moves across the Great Lakes on Saturday, it should have the effect of pulling all of the dry air now in place west of the Appalachians down to the central Gulf Coast and points west downstream into the mid-Atlantic and New England resulting in some clearing from southwest to northeast Saturday night and Sunday. Of course that also means the places that got cloudy in the mid-Atlantic yesterday will have a 5-day stretch of pretty much sunless weather again before it proudly and boldly returns on Sunday. And with it raining now and likely to rain at least part of the time into Saturday, it's not exactly going to mean good outdoor weather for cleaning up the yard, or putting up the Christmas decorations or even logging a few more miles on the bike, like I WILL be able to do this afternoon and again tomorrow as I draw within 500 miles now of my yearly goal of 9,000 miles! And yes, Tom, that was for you! ;)

To the west, the COMPLAINT - yes, COMPLAINT I said, is the LACK OF COLD!!! Can you believe it? It's just the 11th of November, and the run of mild days over the past three to four weeks is getting many people upset by the lack of arctic air! My first comment is 'Are you nuts???' But my more calculated response is to be patient. After all, winter does not start for three weeks yet, 41 days if you go with the date of the winter solstice.

You all are seeing the same things I'm seeing. It's not cold in too many places right now, and the prospects for substantial change any time soon are limited. To be honest, it is turning cooler now in the Northwest, and that's a cooling trend that will spread south and east the rest of the week and will cover the Rockies this weekend. As I've stated before though, that's not so much a result of arctic air flowing in behind a cold front, but more a product of much lower heights, which, when loosely translated, means a cooling of the column of air above.

The first significant front and upper-level trough coming inland now will spread showers of rain and mountain snow through the Northwest into the northern Rockies later today and tonight. The southern end of the front will squeeze some rain showers out of the clouds across northern California tonight and early tomorrow.

A second disturbance rolling into the Northwest late tonight and tomorrow will enhance the showers (rain and mountain snow) across the region down into Utah and Colorado later tomorrow and tomorrow night and push the cold front into the Southwest deserts.

Still another disturbance will crash into the Northwest late tomorrow night and Friday morning, spreading more rain and mountain snow inland. That'll lead to more snow in the mountains of the central and northern Rockies Friday night and Saturday.

After that, there will be a bit of a break in the West, as the next big ticket item will send a strong storm crashing into British Columbia Saturday. The heaviest rain and mountain snow by far will stay north of Washington, though it will turn wet there with some showers later Saturday and Saturday night west of the Cascades.

Aside from that, the main message is the utter lack of arctic cold. It's just not to be seen across Canada right now, and there's no transport mechanism to get it into North America for the next couple of weeks, with the one notable exception of Alaska. The strong jet across the Pacific is bringing storm after storm under the state, and that is allowing the cold to grow across the interior. But when I study forecast surface charts across Canada looking forward toward Thanksgiving, I don't see high pressure areas. In my years of studying the weather, that's one thing I like to see if I want to forecast cold down the road to come into the northern Rockies, the northern Plains and points downstream. Until that changes, I would not bet on any large-scale areas of below-normal temperatures for at least the next two weeks.

In talking earlier today with one of our in-house master weather experts who has seen a lot in his years in the business, Elliot Abrams was wondering aloud that with El Nino still gaining strength, that we're seeing a flood of Pacific air across the country that may not end any time soon. Part of his point was related to the very time El Nino, and how its tied to the time of Christmas, when El Nino was most noted by those who felt its effects along the west coast of South America. Basically, the point is that it's unlikely to start falling apart any time soon, especially not with the 100-150 meter subsurface temperatures still growing warmer and expanding eastward across the central Pacific. And perhaps that's another reason to hold off on laying the cold card for a while.

One final point, and one that I can't say for sure how valid it is, but I'll throw it out there as some chum to feed on, anyway. In my limited studies of arctic air masses, it seems as if they tend to have a fairly dominant location during the course of a winter season. That's not to say they can't break down and migrate from one part of the Northern Hemisphere to another, but if they tend to show up in Siberia, for instance, that's where it tends to be for more of the winter as opposed to other locations. That would imply, at least in my mind, that it might be hard to get more than smaller pieces of it to break away for any length of time and end up in North America.

Just some food for thought.

Remember, it's still ONLY November. There's still plenty of time for winter to show up. I recall the winter of 1993-1994 as being dead on arrival with virtually no snow through the end of December. When it hit in very early January, it never quit, with 100 inches in three months. I remember having no place to put the snow by the driveway, and having to get out and shovel even on the sunny days because the wind would drift the snow back into the driveway. So even though for most east of the Rockies right now the prospects of winter getting started any time soon appear bleak at best, be patient.

A quick final thought on this Veterans Day. Thank you, thank you, thank you to the veterans of our armed forces who have served this country to protect the precious freedoms we enjoy, the ones that are slowly but surely being stolen from us from within. Thanks to my dad who went into the Navy in 1944 to become a pilot and turn back those who would steal out freedoms from without. If you know of a veteran, and I bet you all do, tell them thank you.

Posted by Joe Lundberg on Wednesday, November 11, 2009 11:35 AM
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