Sub-TD - Andrea

[Mondy]

Seen better looking systems skim past north of Scotland in winter

[summer blizzard]

Ultimate insult lol..

I had not realised it looked so bad, the centre must relocate to the south east if this system is to survive for any length of time.

Looks like the hurricane which struck Spain actually.

Edited May 10, 2007 by summer blizzard

[kold weather]

Hi SB, its not really surprising though that its fairly quickly lost its convection, given the three factors i mentioned in this morning's post, which to sum up were:

1: Now its close to the coast its circulation is absorbing quite a bit of dry air, esp so given the drought in the Se states.

2: shear has really picked up recently and has been blowing any meaningful convection to the east of the center and while moving slowly the LLC has already outran the convection, now the LLC is exposed and on life-support---think Chris last year.

3: It has entered both cooler and more shallow energy, the heat content is much reduced compared to the gulf stream where it pepped up and as a result because of less energy present for it to use its weakening, in truth the area its in is not yet conducive for tropical storms to sustain themselves, though it'll only be another 45 days or so before that isn't true.

Anyway worth noting it has been downgraded and is now a 30kt sub-tropical depression and should continue to weaken before dissipating. It still has a decent LLC present mind you and while convection is nearly all gone the lows structure is clearly still visible and so is the LLC, that vigorous LLC combined with the HP gradient to its north should ensure that it'll only slowly wind down from now on. The bad news for this system is that broad LLC looks pretty dominant and I don't think the center will relocate unless it winds down but if it does that given the set-up presently I don't think it'll ever get going again...

Alas, still a neat system, if very weird in regard to its satellite presentation!

Edited May 10, 2007 by kold weather

[WhiteFox]

Andrea dead in the water!

Gave some pretty good waves and high winds on the Carolina coastline for a day or two, and raised relative humidity a bit in South East Georgia and North East Florida but that was about it. Some thunderstorms may be sparked still, but the drought-ridden areas of South East Georgia and North East Florida remain parched and on fire. Large areas remain ablaze and red flag warnings are still in effect. The people down there are praying for a tropical depression to relieve the drought! Incidentally, Tennessee has recorded its driest start to the year on record. The whole South East US is currently well below average on rainfall.

[kold weather]

Intrestingly over the past 6hrs or so convection has got going again very close to the cente rof the circulation. It is fiarly isolated however its intresting to note the convection is deeper then its had for pretty much the whole of its life and its centered bang over the system, wit hthe Sat.estimates now showing it as purely tropical and at TD strength as well again. Also worth noting that its now back over warmer water sof the gulf stream again, though they are more shallow the heat content is probably that bit higher which is probably allowing the system to turn completly barotropic. The only problem is its still very weak and will have to keep the convection for a while yet. Right now its classed as a remanant low BUT if the convection can maintain itself then I'd watch just in case it does get re-upgraded, because theres a chance IF it does it'll be tropical depression, rather then subtropical IMO.

Track should eventually take it out to sea where it'll die and take on cold core properties as a cold front digs down from the north.

[Calrissian]

The Andrea story continues (sorta)

Some pretty good developments indeed, and its looking reasonable 50/50 chance of spinning up nicely.

Q. If this area develops into some level of storm, does that qualify as a new name, or will they use Andrea ? From the tone of the recent NHC texts, it looks like they've already closed the book on Andrea.

Calrissian: ready for Barry

[kold weather]

Nope its still Andrea, Ivan in 2004 pretty much set the president for these systems. It died, then its circulation eventually did a loop-de-loop back out into where Andrea is now, then headed back across Florida and into the Gulf where it re-formed again about 5 days later as Ivan. I think the key is the circulation doesn't die and as long as there is a circulation then it would have came from the low previously. In this case its pretty obvious this is the case and that the NHC have even said its a remnant low and they are now watching it for re-development again, so yep its still Andrea.

By the way as I just said a special tropical disturbance statement was made about an hour ago effectively saying that they are now watching Andrea's remains for re-development as a tropical depression and note its a tropical, not subtropical in nature, as I said in my previous post the warmer gulf stream waters its over have a higher heat content and therefore more energy to use and so the deeper the convection which we are seeing now. Its still got a good circulation, there is some convection right over the center so I'd guess its probably very close to becoming TD Andrea IMO, though whether or not the convection can keep going long enough for it to be re-upgraded again is another matter.

Still as I said this system would take some time to wind down and given its right now over the gulf stream it might just have a shot at surviving and getting upgrade again, but we'll watch and see what happens i suppose, but whatever happens Andrea is still an interesting first system of the season.

PS-tropical models running again...take Andrea back upto 50kts as it zooms away into the Atlantic as a hybrid again...however I think they are being way too agresssive.

Edited May 11, 2007 by kold weather

[Somerset Squall]

Andrea is certainly a fighter! Interesting times.

[summer blizzard]

...SPECIAL FEATURE...

A 1005 MB BROAD AREA OF LOW PRESSURE...THE REMNANT OF

SUBTROPICAL STORM ANDREA...IS CENTERED NEAR LATITUDE 29.0 NORTH

AND LONGITUDE 78.3 WEST AT 12/1500 UTC. SATELLITE IMAGERY AND

SURFACE OBSERVATIONS INDICATE THE SYSTEM HAS BECOME BETTER

ORGANIZED...AND IT COULD BECOME A TROPICAL DEPRESSION DURING THE

NEXT 24 HOURS AS IT MOVES SLOWLY TOWARD THE NORTHEAST. ONCE

AGAIN...CONVECTION HAS FLARED UP NEAR AND EAST OF THE CENTER.

INTERESTS NEAR THE SOUTHEAST COAST OF THE UNITED STATES SHOULD

CONSULT PRODUCTS ISSUED BY LOCAL NATIONAL WEATHER SERVICE

FORECAST OFFICES.

[summer blizzard]

...SPECIAL FEATURE...

A 1008 MB LOW...THE REMNANT OF SUBTROPICAL STORM ANDREA...IS

CENTERED ABOUT 250 MILES EAST OF DAYTONA BEACH FLORIDA.

SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS ENE OF THE

CENTER WITHIN 60/75 NM RADIUS OF 30N75W. THIS SYSTEM HAS NOT

BECOME ANY BETTER ORGANIZED SINCE YESTERDAY. ALTHOUGH NO

SIGNIFICANT DEVELOPMENT OF THIS SYSTEM IS EXPECTED...ONLY A

SMALL INCREASE IN ORGANIZATION WOULD RESULT IN THE FORMATION OF

A TROPICAL DEPRESSION. THE LOW IS MOVING SLOWLY ENE AND A

CONTINUED MOTION AWAY FROM THE SE US IS EXPECTED DURING THE NEXT

24 HOURS.