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Invest 97L off Southeast U.S. Coast; Tropical Storm Ida Churns the Central Atlantic

By: Bob Henson and Jeff Masters 3:43 PM GMT on September 22, 2015

An area of disturbed weather off the coast of North Carolina (Invest 97L) is bringing heavy rains to the waters just offshore from the Outer Banks of North Carolina, where a High Surf Advisory for waves of 6 - 9 feet is posted. The disturbance is under high wind shear of 20 - 30 knots, and there is plenty of dry air around it, which is inhibiting development. Satellite loops on Tuesday morning showed that 97L had some rotation but no surface circulation, and a modest area of heavy thunderstorms that were increasing in intensity and areal coverage. Long-range radar on Tuesday morning from the Cape Hatteras, North Carolina radar showed no spiral banding or signs of organization to 97L's precipitation echoes. 97L will move slowly west-southwest the next few days, bringing strong winds and occasional heavy rains to the coast of North Carolina Tuesday and Wednesday, and to the coast of South Carolina on Wednesday and Thursday. An upper-level trough of low pressure along the U.S. East Coast will bring high wind shear over 97L for the remainder of the week, which will make development difficult. None of our three reliable models for predicting tropical cyclone genesis show development of 97L into a tropical or subtropical cyclone. In their 8 am EDT Tuesday Tropical Weather Outlook, NHC gave the disturbance 2-day and 5-day odds of development of 10% and 20%, respectively.


Figure 1. Latest long-range radar image from the Cape Hatteras, North Carolina radar.


Tropical Storm Ida no threat to land
Tropical Storm Ida is essentially stalled out over the Central Atlantic, well away from any land areas. Satellite images on Tuesday morning showed that Ida continued to struggle against moderate wind shear, with the center of circulation partially exposed to view, and all of Ida's heavy thunderstorms limited to the southeast side of the center. Ida will meander slowly today through Thursday, but by Friday, a trough of low pressure passing to its north will likely pull Ida to the north. It appears unlikely that Ida will pose a long-range risk to North America.


Figure 2. Latest satellite image of Tropical Storm Ida.

Gulf of Mexico development next week?
A southerly flow of moisture from the Western Caribbean and Southern Gulf of Mexico towards the northern Gulf of Mexico will develop this weekend, and the long-range forecasts from the GFS and European models are showing an area of low pressure capable of becoming a tropical or subtropical depression forming near Mexico's Yucatan Peninsula on Monday. Wind shear is likely to be moderate to strong over the region, limiting the potential for this system to strengthen. The models are currently predicting that this system will get pulled northwards to affect the U.S. coast from Louisiana to Florida by the middle of next week, but a strong trough of low pressure over the Western Gulf of Mexico will likely bring high wind shear to the Gulf, limiting the odds of a this system becoming a tropical or subtropical storm that will hit the U.S. next week.

Tropical Storm Malia moving through Central Pacific
Tropical Storm Malia formed on Monday and moved though the Papahanaumokuakea Marine National Monument, several hundred miles west of the Hawaiian Islands. Malia is headed north-northwestwards at 8 mph and will likely become an extratropical storm on Wednesday, between Hawaii and Alaska's Aleutian islands. Malia was the record 6th named storm to form in 2015 in the North Central Pacific (between 140°W and the Date Line.) According to wunderblogger Dr. Phil Klotzbach, prior to 2015, the previous record for named storms in the North Central Pacific for an entire season was four set in 1982. The other named storms that formed in the North Central Pacific in 2015 were Halola, Ela, Iune, Kilo and Loke. This year's record activity has been due to unusually low wind shear and record-warm ocean temperatures caused by the strong El Niño event underway.

TD 16E’s rains less than expected in Southwest
After moving into northwest Mexico on Monday, Tropical Depression 16E quickly dissipated, with no discernable surface circulation detectable in the depression’s remnants over Arizona by early Tuesday morning. The remnants are now being swept northeastward in fast upper-level flow between a ridge over Texas and a persistent upper low over southern California. Between the system’s rapid motion and disorganized state, plus drier air infiltrating at upper levels, the rainfall associated with TD 16E’s remnants was less intense and widespread than earlier expected. Reports from CoCoRaHS observers on Tuesday morning for the preceding 24 hours showed most of the Phoenix area getting little more than sprinkles, with about 0.45” recorded on the eastern fringes of the metro area. Reports in the Tuscon area ranged from about 0.5” to more than 1.5”, with around 3” recorded well south of town in Santa Cruz County. Nogales, AZ, picked up 1.99”. Further west, the upper-level low over southern California was another underperformer in terms of rainfall. The San Diego area received just trace amounts, and the Los Angeles metroplex stayed high and dry.


Figure 3. Washes quickly filled up in Tuscon, AZ, as rains associated with the remnants of TD 16E reached town on Monday, September 21, 2015. Image credit: wunderphotographer pjkace70.


Figure 4. Heavy rains sweep across the countryside southwest of Phoenix near Gila Bend, AZ, on Monday, September 21, 2015. Image credit: wunderphotographer Milker13.

Another Pacific typhoon may develop this week
Tropical Depression 21W, located more than 300 miles west of the Marianas Islands in the open Northwest Pacific, appears destined to become the region’s 21st named storm and 13th typhoon of 2015. Moderate wind shear has kept 21W somewhat disorganized, despite warm sea-surface temperatures: convection is focused to the west of the ill-defined center of circulation. TD 21W should move into a more favorable spot on the southwest corner of an upper-level ridge by midweek. The Joint Typhoon Warning Center projects that TD 21W will be a recurving Category 4 typhoon by Sunday. It is too early to know whether the expected recurvature will be sharp and soon enough to spare Japan or neighboring areas from any typhoon-related impacts. This year has been exceptionally busy in the Northwest Pacific: as of mid-August, the region had broken its record for the greatest amount of accumulated cyclone energy for any year since 1950.

Wunderblogger Steve Gregory has an update on El Niño in his Monday afternoon post. Later today, we’ll have a post on this week’s climate-related events in Washington, D.C., and New York and how carbon dioxide emissions have evolved over the last four-plus decades.

Bob Henson and Jeff Masters


Figure 5. Latest satellite image of Tropical Depression 21W.

Hurricane

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Thanks Doc! Quite gusty here in Wilmington this morning.
Thanks Bob & Jeff. Glad the southwest wasn't washed away. Wish more rain would have come to California where they need it.
Scattered CloudsScattered Clouds
79°F
Feels Like: 81°
Wind Chill: 79° Ceiling: Unl
Heat Index: 81° Visibility: 10.00mi
Dew Point: 68° Wind Speed: 17mph
Humidity: 69% Direction: 20° (NNE)
Pressure: 30.02" Wind Gusts: 25mph
Rep

Conditions in Wilmington NC this am with low just off shore

Me remembers this one








The October Thrill along TX coast. One of three that entire year!

Allison
Chantel
Jerry

That was an active year for me, 1989. 9 years old, the previous year in 88 was the Gilbert scare. After the 89 season I was full active weather nut since then.
This blog article and the previous blog article were each posted at 3:43 PM GMT.
Wilmington NC NWS. Its clear and very gusty


.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM TUESDAY...A PRETTY GOOD AREA OF CLEARING HAS
DEVELOPED ACROSS MOST OF THE CWA WITH THE EXCEPTION OF THE EXTREME
WESTERN AREAS. I HAVE ADJUSTED CLOUD COVER DOWN AND TEMPERATURES
UP TO ADDRESS. STRONGER WINDS ALSO MIXING DOWN IN THE WARMER AREAS
AND I HAVE BUMPED UP THE GUSTS AS WELL. HIGH RESOLUTION GUIDANCE
SHOWS LITTLE IF ANY CHANCE OF RAIN FOR THE REMAINDER OF THE DAY
AND I HAVE ALL BUT REMOVED ANY MENTION. NO OTHER CHANGES.
12Z GFS appears to be taking 97L across N FL. Interesting as 12Z NAM did the samething. I wonder if models are seeing this low SSW of 97L as the more dominate one.


Quoting 7. K8eCane:

Wilmington NC NWS. Its clear and very gusty


.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM TUESDAY...A PRETTY GOOD AREA OF CLEARING HAS
DEVELOPED ACROSS MOST OF THE CWA WITH THE EXCEPTION OF THE EXTREME
WESTERN AREAS. I HAVE ADJUSTED CLOUD COVER DOWN AND TEMPERATURES
UP TO ADDRESS. STRONGER WINDS ALSO MIXING DOWN IN THE WARMER AREAS
AND I HAVE BUMPED UP THE GUSTS AS WELL. HIGH RESOLUTION GUIDANCE
SHOWS LITTLE IF ANY CHANCE OF RAIN FOR THE REMAINDER OF THE DAY
AND I HAVE ALL BUT REMOVED ANY MENTION. NO OTHER CHANGES.


It appears 97L is relocating much further SW and the 12Z models are beginning to jump on this. Very interesting.
A little cloudy today here in NYC, but the temperatures the past few days have been perfectly comfortable. Today is prime car-washing type weather.

That being said, we could really use some precipitation. We're starting to accumulate some significant deficits.
Quoting 4. K8eCane:

Scattered CloudsScattered Clouds
79°F
Feels Like: 81°
Wind Chill: 79° Ceiling: Unl
Heat Index: 81° Visibility: 10.00mi
Dew Point: 68° Wind Speed: 17mph
Humidity: 69% Direction: 20° (NNE)
Pressure: 30.02" Wind Gusts: 25mph
Rep

Conditions in Wilmington NC this am with low just off shore
There are lows all over the place this morning! :-)

I have a thunderstorm headed toward me from the south if the shield will let up for about a half hour or so. If not, back to dragging hoses around.

Quoting 8. StormTrackerScott:

12Z GFS appears to be taking 97L across N FL. Interesting as 12Z NAM did the samething. I wonder if models are seeing this low SSW of 97L as the more dominate one.





I dont know about the models STS. But i think something is brewing out there
Big changes happening with 97L as center has relocated.

Quoting 12. K8eCane:



I dont know about the models STS. But i think something is brewing out there


That is what the GFS is showing. Doesn't matter as it stays weak no matter what and where ever it goes you may not not even notice except an increase in rain.
Quoting 11. sar2401:

There are lows all over the place this morning! :-)

I have a thunderstorm headed toward me from the south if the shield will let up for about a half hour or so. If not, back to dragging hoses around.





Hope ya get your thunderstorm sar! Do we have 98 there? or is that the next number?
12Z GFS then tries to form another low in the same area. Very complicated mess for the SE US.

Quoting 14. StormTrackerScott:



That is what the GFS is showing. Doesn't matter as it stays weak no matter what and where ever it goes you may not not even notice except an increase in rain.


Already noticed. Quite gusty today because of it
And seems to be getting gustier
And no rain BTW
Eric Blake @EricBlake12 3h3 hours ago
Still no #hurricanes in Atlantic basin west of 55W-1st time since 1914 that 0 noted by this late in the year
Philip Klotzbach@philklotzbach 5h5 hours ago
The Atl has had 63 hurricanes since FL had its last, Wilma,'05. Prior record was 33 between David '79 & Elena '85.
19. 7544
Quoting 13. StormTrackerScott:

Big changes happening with 97L as center has relocated.




further south the new low ? tia
Thanks for the new Blog; if a Yucatan low does materialize next week, and sheer remains high, it could end up as a rain event for someone in the Northern Gulf or Florida downstream.

That burst of convection with 97L off the coast might be related to the warm waters/gulf stream location there in spite of the wind shear:


97L
Updated (11:00 am) CIMMS shear chart; 97L is not in a favorable environment for much development regardless of sst's:


And here is the upper level trof that is shearing 97L; not much room to breathe


Quoting 25. weathermanwannabe:

And here is the upper level trof that is shearing 97L; not much room to breathe





You can tell its getting sheared on visible. Can tell its out there though
Quoting 20. Starhopper:





Looks like a disorganized mess still..
Quoting 29. Articuno:



Where's the center? Looks like a disorganized mess still..

Yeah, I was trying to spy it in there lol. In the vis I see rotation bout it.
Here's where it is going tho : )

Seems the Atlantic and GOM are pretty much closed for business due to shear. Best some of us can hope for is some rain producing tropical lows in the areas that need it.

More green appeared in central region past few days.
Quoting 31. 69Viking:

Seems the Atlantic and GOM are pretty much closed for business due to shear. Best some of us can hope for is some rain producing tropical lows in the areas that need it.


Hopefully someone who needs it and not someone who has already been innundated.
GFS HAS SHIFTED TOWARDS LOUISIANA
Quoting 32. Starhopper:


More green appeared in central region past few days.


I live right in the middle of that nice red section in NW Florida, 3rd county East of the Alabama state line! Been feast or famine this year all summer. We'll go 3-6 weeks with no rain and then in a day or two get 1-2 inches. With our sandy soil we start drying up after 1 week of no rain, been 2 weeks now and you can already see some younger trees changing to their fall colors due to the lack of moisture, definitely not due to cool weather. Highs have been 85-90 everyday all month.
Welp, it's all a sheared up mess today it seems. Will check back later. : )
Quoting 35. HurricaneAndre:

GFS HAS SHIFTED TOWARDS LOUISIANA



That would be nice for NW Florida, that's what we need, a weak system that goes to our West so we are on the wet East side of it!
Quoting 37. 69Viking:



I live right in the middle of that nice red section in NW Florida, 3rd county East of the Alabama state line! Been feast or famine this year all summer. We'll go 3-6 weeks with no rain and then in a day or two get 1-2 inches. With our sandy soil we start drying up after 1 week of no rain, been 2 weeks now and you can already see some younger trees changing to their fall colors due to the lack of moisture, definitely not due to cool weather. Highs have been 85-90 everyday all month.

I could plan a fishing trip there. It will rain guaranteed!! : ) Yes is super hot. When sun is out well over the 90s daily here in SW Florida and sauna type muggy. Good on rain after last few weeks. I will hope for some rain for you all soon. Good luck.
Looks like 97L has a chance to be a late-September Claudette. Developing and disappearing just as quickly, the Gulf Stream has a weird way of making magic.

And Ida is a candidate to be 2015's Nadine. Very doubtful she will love that long, but she may end up being the longest-lived Atlantic cyclone this year, by far.
Perfect weather in S C IL, .4" w/ front passage Fri. Since then, low 70s / upper 40s, low 50s. Next 7 days showing low 80s, mid to upper 50s. Corn & beans coming out pretty quickly now, have heard some early corn fields were very variable.

Currently 75 w/ 50 dew pt (were as low as mid 40s yesterday), press 30.2", variable S-E winds w/ an amazing gust of 4 :)
Quoting 40. Starhopper:


I could plan a fishing trip there. It will rain guaranteed!! : ) Yes is super hot. When sun is out well over the 90s daily here in SW Florida and sauna type muggy. Good on rain after last few weeks. I will hope for some rain for you all soon. Good luck.



Thanks, hopefully you'll get some cooler weather soon too. It's been a long time since I remember going this far into September without a good cold front that dropped temps considerably..
Quoting 43. 69Viking:



Thanks, hopefully you'll get some cooler weather soon too. It's been a long time since I remember going this far into September without a good cold front that dropped temps considerably..


There was a front about a week ago that brought much cooler temps and dewpoints to N FL. Jacksonville had a record low.
Quoting 39. 69Viking:



That would be nice for NW Florida, that's what we need, a weak system that goes to our West so we are on the wet East side of it!


Yeah, whatever does form in the GOM will most likely be very rain heavy on the east side. The west side could be pretty dry if the shear pattern continues across the region.
GFS has Ida becoming a hurricane at 30N 40W

Euro cranks Ida up to a Cat 5.

I think I will go with the GFS solution...

Quoting 10. LongIslandBeaches:

A little cloudy today here in NYC, but the temperatures the past few days have been perfectly comfortable. Today is prime car-washing type weather.

That being said, we could really use some precipitation. We're starting to accumulate some significant deficits.


No doubt! Pretty dry here in NYC, but a perfect night for a Mets game!
At least 2 lows now :

Quoting 44. tampabaymatt:



There was a front about a week ago that brought much cooler temps and dewpoints to N FL. Jacksonville had a record low.


I don't count lows in the mid 60's as a big cool down and that's about as cool as we've been so far this year. The record low for today is 48 so we can get a lot cooler without even breaking a record.
ROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT TUE SEP 22 2015

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

The National Hurricane Center is issuing advisories on Tropical
Storm Ida, located a little more than 1000 miles east of the
northern Leeward Islands.

1. An elongated area of low pressure located a couple of hundred
miles southeast of Cape Hatteras, North Carolina, is producing
disorganized showers and thunderstorms. This system is forecast
to move westward, and only slight development is anticipated before
the system moves inland in a couple of days.
* Formation chance through 48 hours...low...10 percent
* Formation chance through 5 days...low...10 percent
Quoting 52. 69Viking:



I don't count lows in the mid 60's as a big cool down and that's about as cool as we've been so far this year. The record low for today is 48 so we can get a lot cooler without even breaking a record.


There was a report of 49 about 10 days ago in the FL Panhandle from someone on here. I believe it was north of Destin.
Quoting 26. tampabaymatt:




Storms getting closer to Tampa Matt. Looks as if the HRRR is playing catch up now.
Rain on the radar just to our North, now if it just holds together and moves South we'll be in luck!

Quoting 52. 69Viking:



I don't count lows in the mid 60's as a big cool down and that's about as cool as we've been so far this year. The record low for today is 48 so we can get a lot cooler without even breaking a record.


I would love to see lows in the mid 60s here in the Tampa Bay area. We have approached record highs every day this week so far and it's just unbearable outside in the sun. Hopefully we get a front to clear us sometime soon, though that doesn't look likely.
Little spin on the loop due South of the Florida Panhandle that is going nowhere (except inland) due to the shear:

Quoting 54. StormTrackerScott:



There was a report of 49 about 10 days ago in the FL Panhandle from someone on here. I believe it was north of Destin.


Maybe North of the coast, we can be 10+ degrees warmer along the coast right now with water temps still in the low 80's. Ok, I went back and looked at the weekend of the 13th we had one morning it got down to 56 and the high was 82 that day. Since then highs have been 85-90 with lows 67-72. I looked at the extended forecast and it looks like we'll be slowly cooling down but right now we're still 5-10 degrees above averages for this time of year.
Quoting 58. weathermanwannabe:

Little spin on the loop due South of the Florida Panhandle that is going nowhere (except inland) due to the shear:




All these lows in the Gulf could signal the developments of future nor'easters.
Quoting 49. HurricaneAndre:


DOOM.
Bring it. I'll buy the popcorn and all the beer.
Quoting 58. weathermanwannabe:

Little spin on the loop due South of the Florida Panhandle that is going nowhere (except inland) due to the shear:




Look @ this the whole Western Atlantic is a sheared mess.

Quoting 61. Sandcat:

Bring it. I'll buy the popcorn and all the beer.


Tell the Canadians no please.
I am going wade fishing on the Big Bend coast tomorrow morning before the supposed "lows" get here next week............................. Got some wind at my back out of the NE with a tree-line behind me as well at my spot per the current forecast so I should be able to cast far out to the first trough where the bigger Trout cruise and have relatively calm waters right in front of me (as opposed to a light chop a little further out in Appallachee Bay).

Just letting Yall know I will not be blogging on here tomorrow.......................................... . :)
12z Navgem looks to be active..

Been an OH ficial member 9 years today. Made some good friends here, and hold even more in high regard, thanks for letting me play Doc.
Robust African wave to exit the coast tomorrow. This wave will come off almost where the wave which spawned Ida came off.
69. 7544
Nice ull east of the bahamas could it work its way down to the surface?


Robust African wave to exit the coast tomorrow. This wave will come off almost where the wave which spawned Ida came off.


doesn't look like shear should be a factor




Damm 12Z Euro shows a huge system in the Gulf not very strong but a very large moisture/circulation that encompasses the whole Gulf!


Still at it.
"Tropical Strom Malia... moved though the Papahanaumokuakea Marine National Monument, several hundred miles west of the Hawaiian Islands..."
In reality, this monument is within, not west of, the Hawai'ian Islands. Hawai'i stretches further west and north than most people imagine. This image is a wiki link.


image credit: wikipedia commons
Some nice storms to my North but so far nothing for my area....

Quoting 66. indianrivguy:

Been an OH ficial member 9 years today. Made some good friends here, and hold even more in high regard, thanks for letting me play Doc.
And it's been a pleasure having you around as well. I really enjoy reading about your work as a Riverkeeper and applaud you for the all the hard work. Florida certainly needs more people like you if Lake O is going to be more than an open sewer in the future.
Quoting 47. FunnelVortex:

GFS has Ida becoming a hurricane at 30N 40W




What's that to the NNE of it?
Quoting 66. indianrivguy:

Been an OH ficial member 9 years today. Made some good friends here, and hold even more in high regard, thanks for letting me play Doc.


Congrats Marty. Enjoyed and appreciate all you do to try to preserve our Florida heritage all these years!
Quoting 75. 69Viking:

Some nice storms to my North but so far nothing for my area....


I lucked out. The usual Eufaula Shield was down for one storm that passed through. Not a gutter crusher, but I got 0.45", which is the most in about 10 days. Looks like it's over for the rest of the day but we are entering a wetter pattern for the next five days or so. Maybe we'll both get lucky...at least with some rain. :-)
As the ULL continues to pull away from Ida shouldn't the shear drop off some and give her a chance to strengthen? She almost looks to be drifting South or SW.
Quoting 69. 7544:

Nice ull east of the bahamas could it work its way down to the surface?
Yes. Maybe. No.

I assume that was a rhetorical question. :-)
LLC relocation in progress?

Quoting 77. Articuno:



What's that to the NNE of it?


Some extratropical storm.
Quoting 79. sar2401:

I lucked out. The usual Eufaula Shield was down for one storm that passed through. Not a gutter crusher, but I got 0.45", which is the most in about 10 days. Looks like it's over for the rest of the day but we are entering a wetter pattern for the next five days or so. Maybe we'll both get lucky...at least with some rain. :-)


Awesome, glad you got some rain out of it, maybe we'll get lucky and get a nice shower before things calm down after sunset. I'm glad you mentioned Eufaula, I was wondering how far North of me you were. I hunt West of Georgiana in the Northern tip of Conecuh, county but live on the outskirts of Fort Walton Beach.
Quoting 43. 69Viking:



Thanks, hopefully you'll get some cooler weather soon too. It's been a long time since I remember going this far into September without a good cold front that dropped temps considerably..

Usually we get a few September days that are on the cool side of comfortable or just plain chilly in DC metro. So far, not this year.
This is what a Super El-Nino looks like. Looks like the heat has been turned up across nino 1&2.

Quoting 80. 69Viking:

As the ULL continues to pull away from Ida shouldn't the shear drop off some and give her a chance to strengthen? She almost looks to be drifting South or SW.
Ida should slide generally easterly to southeasterly for the next couple of days below a ridge of high pressure. This should cause a decrease in shear but it will still be high enough to prevent intensification. Once the storm is clear of the trough it's stuck in, that will be the best chance for intensification, but that looks to be in three or four days...maybe. Ida is so weak and disorganized right now that remaining stuck in the trough for longer than forecast will weaken the storm even more, and it may even become a remnant low rather than undergo intensification. All that amateur forecasting being said, Ida is one of the most bizarre and difficult storms to forecast I've seen in over 50 years of watching the tropics. I really have no confidence in any forecast for Ida beyond about twelve hours.
JeffMasters has created a new entry.
Quoting 84. 69Viking:



Awesome, glad you got some rain out of it, maybe we'll get lucky and get a nice shower before things calm down after sunset. I'm glad you mentioned Eufaula, I was wondering how far North of me you were. I hunt West of Georgiana in the Northern tip of Conecuh, county but live on the outskirts of Fort Walton Beach.
I remember you talking about your hunting camp before. Today would be an awesome day for some field time. The current temperature is 76, which is the high of the day so far. It's been a long time since the temperature was in the mid-70's at two in the afternoon. Maybe a hopeful sign for the beginning of Autumn tomorrow.
It seems we are under the gun for a heavy rainfall event here in Coastal NC..also looks like our NWS is reading this blog with the superlatives used in today's discussion..

Latest discussion from NWS, Wilmington, NC

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...PRIMARY WEATHER HEADLINE THIS PERIOD TO KICK
OFF AUTUMN IS MOUNTING CHANCES OF APPRECIABLE RAINFALL ACCOMPANIED
BY MAXIMUM TEMPERATURES NEAR TO SLIGHTLY BELOW NORMAL WITH
CONSIDERABLE CLOUDS. SURFACE HIGH PRESSURE WILL STRENGTHEN NORTH OF
THE GREAT LAKES THIS PERIOD...PRESSING A DAMMING WEDGE SOUTHWARD
INTO THE CAROLINAS. CONCURRENTLY A WESTERN ATLANTIC SURFACE LOW WILL
RETROGRADE AND FILL MOVING WSW ONTO THE CAROLINA COAST THURSDAY INTO
FRIDAY. THE DEEP ONSHORE FLOW AND LOW-LEVEL ISENTROPIC OMEGA SHOULD
HELP SPUR GOOD CHANCES OF STRATIFORM RAIN THU AFTN/NIGHT.

SEVERAL MODERATE LOBES OF H7-H5 VORTICITY ARE FORECAST TO ROTATE
ONSHORE THURSDAY WHICH COULD SPAWN ISOLATED EMBEDDED CONVECTION.
PRECIPITABLE WATERS WILL BECOME ELEVATED BY THURSDAY WITH DEEP
E-SE WIND FLOW SURFACE TO 400 MB. IT APPEARS INTO THURSDAY NIGHT
THE THREAT OF LOCALIZED EXCESSIVE RAINFALL MAY COME INTO PLAY
OVERNIGHT INTO EARLY FRIDAY. STRONG HIGH PRESSURE TO THE NORTH AND
ANTICIPATED CLOUD COVER SHOULD KEEP MAXIMUMS IN THE UPPER 70S TO
LOWER 80S THIS PERIOD AND MINIMUMS MIDDLE 60S INLAND AND AROUND 70
CLOSE TO THE COAST.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 3 PM TUESDAY...INCREASING CONFIDENCE IN A HEAVY RAINFALL
EVENT THIS WKND AS AN AREA OF DISTURBED TROPICAL/SUBTROPICAL WEATHER
RETROGRADES BACK TOWARDS THE COAST. THIS OCCURS IN RESPONSE TO AN
UPPER LOW WHICH IS WEAKENING AND DRIFTING WELL WEST AS IT GETS
TRAPPED WITHIN A COL NEAR A LARGE UPPER RIDGE. THE ECMWF LATCHED
ONTO THE HEAVY RAIN IDEA YESTERDAY...AND NOW THE GFS AND CANADIAN
ARE FOLLOWING SUIT. THIS IS LIKELY DUE TO THE WEAKER AND FURTHER
WEST MOTION OF THE UPPER LOW...WHICH IS ALLOWING THE `FLOOD GATES`
TO OPEN TO THE DEEP TROPICAL MOISTURE OFFSHORE.
There is uncertainty regarding the actual track of the storm as it approaches the mid-Atlantic on Sunday.
There is a possibility that the track of the system will remain closer to the mid-Atlantic coast, allowing for a windy, rainy and nasty day from the coastal areas to the Interstate 95 corridor from Philadelphia to New York City.
If the track is farther out to sea, the Interstate 95 corridor may be spared from any rainfall while a brief shower will be possible along the coastal areas. Windy conditions, however, will remain along the coast.
The combination of rain and wind will cause poor visibility for motorists.
Coastal Flooding, Other Concerns
The weather pattern will cause northeasterly winds to increase along the middle part of the U.S. coast.
Rough seas and surf will far precede the rain from the storm.
According to AccuWeather Meteorologist Kristina Pydynowski, "As winds pick up, seas will build and rip currents will increase between high pressure to the north and the storm to the south."
As of Tuesday, seas have built to 6-10 feet off the North Carolina and Virginia coasts.
Winds along the coast can gust past 40 mph.
Gusty winds and low cloud ceilings could cause delays for departing flights.
In addition to the rough seas and stiff winds, some beach erosion and coastal flooding could occur due to the long-duration and slow-moving storm from Tybee Island, Georgia, to Sandy Hook, New Jersey.
In the area from northeastern North Carolina to New Jersey, the effects of the storm will coincide with the proximity of the full supermoon and high astronomical tides.
Atlantic coast communities and property owners along the back bays may want to take preventative action.
Tides generated by the storm may run about 2 feet above published levels.
"The astronomical tides are accounted for in publications," AccuWeather Chief Meteorologist Elliot Abrams said. "However, the astronomical part of the tides this weekend will be higher than most days of the year."
The combination of high astronomical tides and storm tide can cause inundation in areas that typically do not have flooding from either a spring tide or from a storm.
Bathers, boaters and cruise ships will need to exercise caution and heed advisories as they are issued. Many of the beaches do not have lifeguards on duty this late in the season. Rip currents will be much stronger and more frequent than average.
Just as residents, vacationers and cruise interests along the U.S. southern Atlantic coast should monitor the weather this week, people from the U.S. Gulf Coast to southeastern Mexico should keep an eye on the tropics next week.
There is some indication that a tropical system may form near the Yucatan Peninsula and drift northward into the Gulf of Mexico next week.
Meanwhile, Ida will continue to churn waters in the central Atlantic. However, Ida is not a threat to any land areas at this time.