Monday, August 28, 2006

Tue AM update

Even I may be guilty of overdoing it, but maybe it's the ghosts of storms past that looked innocuous and ended up being torrential rainmakers that caught many by surprise. Those of us in the Carolinas to the Mid-Atlantic will welcome the rains that are to come, but it will make for a very wet end to the summer travel season this Labor Day Weekend. Click on the graphic below for the most up-to-date forecast map from NHC.

Ernesto 9

The section I wrote below was issued via the email distribution list this afternoon. Granted my ideas on windspeed intensity may not pan out as I think it is doubtful this storm will ever regain hurricane status again. But in the same breath I think back to Ivan in 2004, and how the models were trying to tell us something about the eventual track, but no one could figure it out until we noticed the circulation center had actually maintained it's structure, crossed back over Florida, reemerged in the Gulf and almost made it back to hurricane strength believe it or not before hitting Texas as a medium-range tropical storm. I wonder if the East Coast stall scenario playing out on the maps is an indication that this will turn into a massive rainmaker.

Ernesto 8

Written at 3:30 PM 8/28


Ever-changing Ernesto has been confounding forecasters, including me, since the first 5 day projection was issued. It’s a good thing we all have instant access to technology and have been able to monitor the movement of this storm. It seems that each time a forecast was issued, the storm was already in the process of undoing that forecast. Obviously my predictions issued on Saturday have proven to be way off, but at least it is a relief to storm weary residents of the Gulf that what I projected did not come true.

My main concern for the future of this storm is the computer models continue to have a difficult time initializing the storm, mainly because the center of circulation keeps reforming in different places. Since the major models commence a data run every 6 hours, the storm has changed so much that by the time an updated forecast track is ready to be issued, the information already seems inaccurate. This is not a knock on forecasters, mind you, it is just one of the many reminders that even the most powerful computers in the world may never be able to uncover the nuances and inner complexities of tropical systems.

That leads me to the big issue…which is almost like a repeat of the winter storm rule: “Predict the High and you predict the storm.” I can’t take credit for the rule, it was created by a Penn State meteorology professor, but I have applied it to my storm analysis and sometimes it works out. That’s where I’m going to hang my hat with Ernesto. Here’s a scenario I see happening based on the uncertainty we’ve experienced thus far..based on a trend first picked up by the European models which is shown below (valid for 7AM Saturday)

Ernesto 10

Several models show a large Canadian high moving off the New England coast by end of the week..but not so much that the high provides an easy escape for Ernesto as with Floyd in 99. The problem is that this could become a defacto “blocking high” because it may not move off fast enough. The storm appears to be heading out to sea or at least raking the coast with tropical storm to hurricane force winds for days on end. When it begins to turn northeast, it appears the Mid-Atlantic is spared (when in actuality a nice soaking rain would be just right about now). Instead of racing off to the northeast, the storm slows and gathering strength over the Gulf stream near the Carolinas. Then, as the high slowly fades east, a trough develops along the Mid-Atlantic, the pressure gradient tightens as the storm approaches, and placement of the high sends a large, slowly eroding hurricane back over the NC-MD I-95 corridor similar to Isabels’s path, only just a bit farther north. Hurricane watches and warnings are quickly raised, but the public is given less than 24 hours notice due to the rapid change in the forecast. The end result is a slow-moving, 75 mph hurricane moving along the DelMarVa or even in the southern bay..stuck between two in the North Atlantic and the other in southeast Canada. (10 PM update: doubtful we'll see winds of that strength now, but we could see the equivalent in rain..5-10")

Post below was written at 5:30 AM 8/28

or maybe the headline should read

Ernesto 6

Now you're saying, "Come on Foot, as if the storm has any control over where it's going." Well, I'd like to counter by saying that although everyone, including me, has been waaay off on the path of this indecisive storm, there is some truth to the idea the storm can determine where it goes next.
Last night I wrote these notes and did not get a chance to post them, but I believe this is still valid considering how much the forecast has changed. While Tampa-St. Pete will be spared a $50 billion direct hit, Miami and the Southeast Coast will get menaced instead for very unpleasant unofficial end to summer.

Ernesto 7

Here's my thoughts on what is happening with the track changes:
- Notice how frictional effects pulled the storm closer to Haiti than originally thought? It's almost as if the island was drawing the storm towards itself.

- Frictional effects can be a double-edged sword.. because once over Cuba, the opposite effect could take place in that once the northern 1/3 to 1/2 of the storm (not the center) crosses over land, the SE quadrant offshore winds will be the last to weaken, and the those winds funneling energy into the storm counter-clockwise could serve as a opposing force. What I mean by this is while I agree Ernesto will be fouled up by the highly mountainous terrain of eastern Cuba, I also think it is possible the storm will not linger over the island as long as is currently being projected. There are some theories (or perhaps it is a verifiable phenomenon of tropical systems) that storm centers can “sense” a source region of warm water and have a tendency to be drawn to the source if it is in close proximity to the center.

- Boy I guess the western flank of subtropical high weakened, like way way more than anyone anticipated. Here we were concerned this storm would be heading for New Orleans, or maybe Pensacola, and 500 miles later, there's speculation it may never actually hit the U.S. This trough that's moving into the northeast really has some cojones being that it's still . summer because it has completely changed the entire life cycle of this storm.

Since today is the first official day of school in Baltimore County and elsewhere I cannot post to the site during the day, but will issue an update via the distribution list this afternoon followed by a website update this evening,


Anonymous said...

RAY- The more I look at this the more I'm concerned for the Mid-Atlantic(Nogaps model)! This model indicates the trough leaving Ernesto to stall over the gulf stream, possibly becoming a major hurricane, and then being forced W into the mid-atlantic!! U may meet Ernesto up close and personal Mr. Foot! We should not let our guard down either Eric!

Anonymous said...

BEN - yeh i agree with Ray. This looks, at the moment, to being influencing the mid atlantic come next weekend. Which is just grand because I move into University in DC on Saturday (currently in SE PA, just outside Philly)

Anonymous said...

RAY- Now looks like it moves inland over sc and just becomes a rain event.

Anonymous said...

BEN - that seems too much of a drastic change. By the way things are going, I doubt that will hold. We'll see what the trends show in the coming model

Mr.B said...

Joe Bastardi from accuweather, says this could be a major east coast event. Also he says he expects at least 3 storms to hit the east coast in the next 2 months. Looks out. We do need the rain. The latest track at 5pm. Put T.D Ernesto right over my backyard here in greencastle,pa.

Anonymous said...

RAY- I doubt it will be a MAJOR event.

E.H. Boston said...

Ok, I see the current NWS forecast projection and they have it going inland over PA. Thats good.

But then I go to and they have a storm track that goes straight out to sea after hitting the Carolinas. Then I go to see the GFS and Ernesto appears to be going right up the coast and slamming into NYC as a T.S. or hurricane?

Anyone have Accuweather Pro? Whats Joe Bastardi saying? Mr. Foot...whats going on with this system? The forecasters here are saying that this storm will hit here on Saturday if it does.

Help us. SNE is so not ready for a hurricane strike, sadly.

Anonymous said...

RAY- Sadly, noone has any idea Eric, I suspect the Gulf. Long range GFS sends us a tropical gift too!

Anonymous said...

BEN - remember when the 5 day forecast was calling for a GOM storm? then it turned into a west coast FL storm, then a S. FL storm.

Now it's an E coast FL/Carolina/Mid-Atlantic storm

The track will continue to be unclear

what I want to know is will it get its act together in respect to intensity, organization and shape?

Anonymous said...

RAY- When it gets the hell outta Cuba!

Anonymous said...

BEN - right i'm going to bed. i better awaken tomorrow morning with this thing looking much better and off land.

Look at the GFS, last 2 runs have shown v heavy rain for the mid atlantic. any thoughts?

Anonymous said...

RAY- Gulf of Mexico.

Anonymous said...

BEN - I actually am becoming v tired of following this storm

i'm starting to lose interest...feels like im wasting my time when the track keeps changing so drastically.

Yet i'll still follow it, for reasons i dont know haha, but it is becoming tiresome

Anonymous said...

RAY- They have the track nailed FINALY, but outside of flooding potential in the mid-atlantic its just NOT A BIG DEAL!!!

Anonymous said...

BEN - just wondering, how is the track nailed? I still believe there are a few more twists and turns to the forecast. Also, what's making the system trend toward the west so much?

Anonymous said...

RAY- 1) The models are all clustered together and have been for the past day as a result of high altidude data gathered from noaa jets.
2)The "storm"(more like an expansive afternoon thunderstorm) is following this tightly clustered track coming into the upper keys now, off around Daytona beach and back in around the carolinas causing flooding in mid atlantic. The storm is not heading west anymore, its goin nw and turning north as forecast. I'm sick of talkin about it... nothn to see here... NEXT!!!!!!!!!!!!!!!!

Anonymous said...

To be fair, 99% of recent tropical systems affecting the mid atlantic have been those flooding rains. How can we forget Floyd? And the lesser systems such as Isabel and Charley? It is a big deal should Ernesto have the same effect, esp if its the same as Floyd....

Mr.B said...

I already heard from the weather channel, Accuweather pro, and a couple of my news channels, that the storm will have more of a effect on the carolinas/mid-atlantic states. According to the latest with the high pressure to the north, the pressure gradient will be tighter over these areas. Maybe 40-50mph winds all the way up to PA and NJ. Also 6-10 inches of rain. This would be one crazy event for me if this holds true, because the track is still right over me.

Anonymous said...

BEN - how about me who has to move into college in DC on Sat!!

Apparently, the GFS has shifted to the east...track still isnt 100% certain, this is getting crazy

Foot's Forecast said...

Yeah Ben, it's like what goes around comes around! Here I thought east coast would be off scot free when in reality we might get the worst of it. It'll be a lot of heavy rain and wind so I guess have a lot of plastic bags to cover your stuff while you move it. Will be an interested weekend for sure.

Anonymous said...

RAY-I DON'T think that 10" of rain and 50MPH gusts is a big deal, but thats just me. IF ur frightened anonymous, by all means send it my way(Boston), I'll take it! GOD AM I BORED... like I said...NEXT!!!!!!!

E.H. Boston said...

RAY...Look at the NAM. I don't know why people are throwing this system away for us. It is still showing this thing coming up at us as a strong tropical system.

Why isn't anyone even mentioning this reliable computer model? If I'm not mistaken, in the winter, I find the NAM much more reliable than the GFS.

Mr. Foot, tell me why the GFS is so much more favored than the NAM? Is it just better at forecasting hurricanes, (It hasn't done a good job with Ernesto.) or is it political?

E.H. Boston said...

Well, I sound like a true weatherman. I take all of that back. Just checked the new NAM and its bringing it to DC then the easterlies are bringing it all the way to CLEVELAND!

All you down there, 10" of rain is not fun AT ALL. May around here was no picnic.

Now I am with Ray...NEXT!

Anonymous said...

BEN - yeh, it's basically turning out to be a dud of a storm, but it's rather a freak too haha (how it deepened over land today, how the track keept changing, how it just wouldnt die over cuba, etc)

question now is, how much rain for DC, Philly etc?

I'm with all of you, though: NEXT!!