Tropical Storm Danny likely to be named today

By: Dr. Jeff Masters , 1:25 PM GMT on August 26, 2009

Share this Blog
3
+

First-light satellite images of the tropical wave (92L) a few hundred miles northeast of the Bahama Islands show that the system has developed an organized surface circulation, and 92L will likely be named Tropical Storm Danny later today. This morning's QuikSCAT pass confirms the presence of a surface circulation, and the satellite saw top winds of 50 mph in a cluster of thunderstorms well east of the center. Wind shear has dropped to the moderate range, 10 - 15 knots. The upper-level low 92L is moving underneath has plenty of dry air in it, and the upper low is injecting this dry air into 92L's west side, keeping and heavy thunderstorm activity from developing on that side. The Hurricane Hunters are in 92L, and have found surface winds up to 57 mph so far this morning. NHC continues to give 92L a high (greater than 50% chance) of developing into a tropical depression by Thursday afternoon.


Figure 1. Water vapor satellite image from 8:15 am EDT 8/26/09 showing dry air associated with an upper-level low pressure system to the west of 92L's center of circulation. Image credit: NOAA/SSD.

The forecast for 92L
As 92L continues to plow through the upper low, the low will weaken, and wind shear is expected to decline to the low range, 5 - 10 knots, by tonight. However, the upper-level low will continue to dump dry, cold air into 92L through Thursday afternoon, slowing down development. By Thursday night, when 92L should be several hundred miles off the coast of northern Florida, the upper-level low may be weak enough and far enough away that 92L will find itself in a region with light upper level anticyclonic winds, which would favor more rapid development. Most of the intensity models, including the GFDL, HWRF, and SHIPS model, forecast that 92L will become a hurricane by Friday. However, this favorable environment will not last long, since a strong trough of low pressure will be approaching the U.S. East Coast on Friday. This trough will bring high wind shear of 20 - 30 knots by Friday night. This trough should be strong enough to turn 92L to the north. The models have come into better agreement keeping 92L offshore as it passes North Carolina, though the storm is certainly capable of giving the Outer Banks a direct hit. As 92L passes North Carolina, it should start heading north-northeast, with a second landfall likely Saturday night or Sunday morning somewhere between Massachusetts and Nova Scotia. At that time, 92L is likely to be a strong tropical storm or weak Category 1 hurricane, with winds in the 55 - 80 mph range. It currently appears that 92L will not bring tropical storm-force winds to the Bahamas or to Florida.

Elsewhere in the Atlantic
The models have been inconsistently predicting formation of several tropical waves coming off the coast of Africa over the next week, and I am going to stop mentioning these forecasts until we get two models predicting the same thing, several model runs in a row.

I'll have an update later today.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 617 - 567

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19Blog Index

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE NEW YORK NY
107 PM EDT WED AUG 26 2009


THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHERN
CONNECTICUT...NORTHEAST NEW JERSEY AND SOUTHEAST NEW YORK.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

HAZARDOUS WEATHER NOT EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

TROPICAL STORM DANNY IS FORECAST TO TRACK FROM NEAR CAPE HATTERAS
SATURDAY MORNING TO THE GULF OF MAINE BY SUNDAY MORNING. ALTHOUGH
THE EXACT TRACK AND INTENSITY OF THIS STORM IS STILL
UNCERTAIN...TROPICAL STORM CONDITIONS ARE POSSIBLE.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

Member Since: Posts: Comments:
i live in wilmington nc and i usually dont get too concerned unless warnings are posted.
watches? NAH been thru too many watches that werent needed in the long run
but if a warning gets put out, i start to listen
Member Since: Posts: Comments:
Member Since: June 13, 2009 Posts: 2 Comments: 11952
614. IKE
Quoting Acemmett90:

wait a second bill started off this way as a yellow circle and who was the idiot who said this is gonna be a slow season lol


2nd attempt to post this....

It wasn't me. I've had 10-4-2 as my numbers since late June.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
hey ya floodman!
Member Since: Posts: Comments:
Quoting tiggeriffic:
said it last night, will say it again today... the actual COC will make the gfs, gfdl, ukmet, etc, all shift to the left shortly...now that danny has been named, updates will be more frequent...and think it is gonna track more to the cmc model than the others....


I agree..I dont think the 12Z runs are set in stone..we need to have a more consistency with each later run...
Member Since: August 19, 2006 Posts: 13 Comments: 15282
Quoting taistelutipu:
RE: Grothar.

Jå, jag har fått din brev, tack så mycket. På ögonblick är jag på arbetet i min byrå. Kanske kan jag skriva svar ikväll men jag har inte haft tid för att skriva någonting om stormar. Förlåt


Look Earl! He's speakin' gibberish!
Member Since: October 18, 2005 Posts: 4 Comments: 3052
Quoting stoormfury:
Strong tropical wave south of the cape verdes shoing signs of organisation. This could be invest 94L

the same thing I was saying
Member Since: June 13, 2009 Posts: 2 Comments: 11952
Quoting iluvjess:
Models should inch more left.


That's what Storm W is thinking as well in his update.
Member Since: Posts: Comments:
12Z GFDL also bullish on a strong hurricane moving up the coast:

Member Since: Posts: Comments:
Quoting IKE:


Get ready for 94L. This one looks like a long-runner.


Yep...Should be another one to watch .
Member Since: Posts: Comments:
Convection is finally starting to find is way around the north to the northwest side. Maybe it will put its clothes on soon
Member Since: Posts: Comments:
Quoting OcracokeISL:
Hello. Just found this website and blog. I am a native of Ocracoke Island on the Outer Banks of NC. We certainly have had our share of hurricanes through the years. With Bill recently passing by offshore causing beach erosion and flattening some of the dune line it has made the only road off the island vulnerable to washout if Danny were to come our way as a minimal hurricane as early forecasts predict.


Just left your little island w/ my family! Love Howards Pub! You guys will be ok down there, OBXer's eat these storms for breakfast.
Member Since: Posts: Comments:
603. BGMom
Quoting mobilegirl81:
Forecasts indicate September is gonna bring the rain.


Boy - I hope that will include the Atlanta area! I tried to mow today and looked like Pigpen on Snoopy - walking in a big cloud of dirt.
Member Since: Posts: Comments:
Models should inch more left.
Member Since: Posts: Comments:
Quoting leftovers:
action in the gulf?


Very high wind shear in the Gulf at the moment, although SST's are very high. Those flare-ups are quite common here in Florida during the summer. Always something watch though, remember Claudette??
Member Since: Posts: Comments:
600. IKE
Quoting Stormchaser2007:
NHC interested in the CV wave.


000
ABNT20 KNHC 261739
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT WED AUG 26 2009

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON NEWLY-FORMED
TROPICAL STORM DANNY...LOCATED ABOUT 445 MILES EAST OF NASSAU IN
THE BAHAMAS.

A TROPICAL WAVE LOCATED JUST SOUTHEAST OF THE CAPE VERDE ISLANDS
OVER THE FAR EASTERN ATLANTIC IS PRODUCING AN AREA OF DISORGANIZED
SHOWERS AND THUNDERSTORMS. CONDITIONS APPEAR FAVORABLE FOR SOME
SLOW DEVELOPMENT OF THIS SYSTEM DURING THE NEXT COUPLE OF DAYS.
THERE IS A LOW CHANCE...LESS THAN 30 PERCENT...OF THIS SYSTEM
BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

PUBLIC ADVISORIES ON DANNY ARE ISSUED UNDER WMO HEADER
WTNT35 KNHC AND UNDER AWIPS HEADER MIATCPAT5. FORECAST/ADVISORIES
ON DANNY ARE ISSUED UNDER WMO HEADER WTNT25 KNHC AND UNDER AWIPS
HEADER MIATCMAT5.

$$
FORECASTER BROWN/BEVEN




Get ready for 94L. This one looks like a long-runner.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Quoting IKE:


It's the link to the NOGAPS model run. I would never put anything on here that would mess someone's computer up.


I'm sure you wouldn't. Thought you'd like to know that that popped up when I tried to access. Might not only be me.
Member Since: Posts: Comments:
Tig!
Member Since: Posts: Comments:
said it last night, will say it again today... the actual COC will make the gfs, gfdl, ukmet, etc, all shift to the left shortly...now that danny has been named, updates will be more frequent...and think it is gonna track more to the cmc model than the others....
Member Since: Posts: Comments:
595. IKE
Danny needs a new wardrobe....

Member Since: June 9, 2005 Posts: 23 Comments: 37858
NHC interested in the CV wave.


000
ABNT20 KNHC 261739
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
200 PM EDT WED AUG 26 2009

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON NEWLY-FORMED
TROPICAL STORM DANNY...LOCATED ABOUT 445 MILES EAST OF NASSAU IN
THE BAHAMAS.

A TROPICAL WAVE LOCATED JUST SOUTHEAST OF THE CAPE VERDE ISLANDS
OVER THE FAR EASTERN ATLANTIC IS PRODUCING AN AREA OF DISORGANIZED
SHOWERS AND THUNDERSTORMS. CONDITIONS APPEAR FAVORABLE FOR SOME
SLOW DEVELOPMENT OF THIS SYSTEM DURING THE NEXT COUPLE OF DAYS.
THERE IS A LOW CHANCE...LESS THAN 30 PERCENT...OF THIS SYSTEM
BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

PUBLIC ADVISORIES ON DANNY ARE ISSUED UNDER WMO HEADER
WTNT35 KNHC AND UNDER AWIPS HEADER MIATCPAT5. FORECAST/ADVISORIES
ON DANNY ARE ISSUED UNDER WMO HEADER WTNT25 KNHC AND UNDER AWIPS
HEADER MIATCMAT5.

$$
FORECASTER BROWN/BEVEN


Member Since: Posts: Comments:
RE: Grothar.

Jå, jag har fått din brev, tack så mycket. På ögonblick är jag på arbetet i min byrå. Kanske kan jag skriva svar ikväll men jag har inte haft tid för att skriva någonting om stormar. Förlåt.

About the Felix entries. If you go back to comment 489 in this blog, P451 has listed all F storms since 1989 including all storms named Felix, namely the F storms in 1989, 1995, 2001 and 2007. This was done in order to find out whether F storms have tendency to hit Florida or not. Results are found under the list.

After this comment you'll find some requests to remove those from the list and I was asking why. Maybe it is a kind of joke I don't get and apparently I'm not the only one since you just asked this question. Probably it isn't very important.
Member Since: Posts: Comments:
591. IKE
12Z GFDL on Danny


12Z HWRF on Danny
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Quoting WxLogic:
575. klaatuborada

Yes, you can rest assured that the NAVY won't be putting viruses on your PC...

All that message is telling you is that their Security Certificate has expired and therefore can't be validated until they buy a new one... and who knows when they'll do that. They may not have the budget for t.


WXlogic is quite correct. I receive the same message with no harm. Those sites are quite secure. I would not recommend the same with other sites, with which you are not familiar or do not trust.
Member Since: Posts: Comments:
I watch StormW's blog personally...if the military trusts him...then i do...
Member Since: Posts: Comments:
Hello. Just found this website and blog. I am a native of Ocracoke Island on the Outer Banks of NC. We certainly have had our share of hurricanes through the years. With Bill recently passing by offshore causing beach erosion and flattening some of the dune line it has made the only road off the island vulnerable to washout if Danny were to come our way as a minimal hurricane as early forecasts predict.
Member Since: Posts: Comments:
This does look mighty good at the moment, not much model support.....

Member Since: Posts: Comments:
Quoting leftovers:
action in the gulf?

afternoon thunderstorms..
Member Since: Posts: Comments:
575. klaatuborada

Yes, you can rest assured that the NAVY won't be putting viruses on your PC...

All that message is telling you is that their Security Certificate has expired and therefore can't be validated until they buy a new one... and who knows when they'll do that. They may not have the budget for t.
Member Since: August 14, 2008 Posts: 4 Comments: 4972
Quoting klaatuborada:


That link comes up as being totally untrustworthy. Is this the true link?

This Connection is Untrusted
You have asked Firefox to connect
securely to www.fnmoc.navy.mil, but we can't confirm that your connection is secure.

Normally, when you try to connect securely,
sites will present trusted identification to prove that you are going to the right place. However, this site's identity can't be verified.

What Should I Do?

If you usually connect to
this site without problems, this error could mean that someone is trying to impersonate the site, and you shouldn't continue.

Technical Details

www.fnmoc.navy.mil uses an invalid security certificate.

The certificate is not trusted because the issuer certificate is unknown.

(Error code: sec_error_unknown_issuer)



Right-click on links in this blog and select "open in a new tab" works best for me. The afforementioned link is good btw.
Member Since: October 18, 2005 Posts: 4 Comments: 3052
581. IKE
Quoting klaatuborada:


That link comes up as being totally untrustworthy. Is this the true link?

This Connection is Untrusted
You have asked Firefox to connect
securely to www.fnmoc.navy.mil, but we can't confirm that your connection is secure.

Normally, when you try to connect securely,
sites will present trusted identification to prove that you are going to the right place. However, this site's identity can't be verified.

What Should I Do?

If you usually connect to
this site without problems, this error could mean that someone is trying to impersonate the site, and you shouldn't continue.

Technical Details

www.fnmoc.navy.mil uses an invalid security certificate.

The certificate is not trusted because the issuer certificate is unknown.

(Error code: sec_error_unknown_issuer)



It's the link to the NOGAPS model run. I would never put anything on here that would mess someone's computer up.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Get ready for the Doomsday HWRF model run results for 12Z. YIKES!

Member Since: Posts: Comments:
Quoting StormW:
TROPICAL WEATHER SYNOPSIS /DANNY/ AUG. 26, 2009 ISSUED 12:20 P.M. EDT


Hey StormW, Grothar here (again). On the water vapor loop, as we all see, the convection is displaced well NE of the center. When the ULL dissipates, as mentioned by Dr. Masters and the NHC, could it steer the center more west? It looks as if the center wants to move more west the NW.
Member Since: Posts: Comments:
Strong tropical wave south of the cape verdes showing signs of organisation. This could be invest 94L
Member Since: Posts: Comments:
Danny should be heading on a general WNW to NW later tonight into tomorrow... based on the 15Z Steering maps... for the past 6HRs the Bermuda High western region has been weakening some...

Member Since: August 14, 2008 Posts: 4 Comments: 4972
thak you StormW...can always count on you! so who ever posted about hatteras...read stormW's blog
Member Since: Posts: Comments:
Quoting WxLogic:


I noticed that too... coinciding with GFS but a bit slower.
Quoting IKE:


You're right. 12Z NOGAPS.....is off-shore with Dan the man all the way up the east coast. Also shows a system cruising through the EATL.


That link comes up as being totally untrustworthy. Is this the true link?

This Connection is Untrusted
You have asked Firefox to connect
securely to www.fnmoc.navy.mil, but we can't confirm that your connection is secure.

Normally, when you try to connect securely,
sites will present trusted identification to prove that you are going to the right place. However, this site's identity can't be verified.

What Should I Do?

If you usually connect to
this site without problems, this error could mean that someone is trying to impersonate the site, and you shouldn't continue.

Technical Details

www.fnmoc.navy.mil uses an invalid security certificate.

The certificate is not trusted because the issuer certificate is unknown.

(Error code: sec_error_unknown_issuer)

Member Since: Posts: Comments:
Quoting VAbeachhurricanes:


yeah, its been altered


that's cool...i wasn't aware of the modifications!

thanks!

you too, Ike!
Member Since: Posts: Comments:
Quoting adjusterx:
Getting some good winds and getting very dark here in PSL,FL. Anybody over on coast area-Jensen,Jupiter,Stuart hows it look over there? I am on wets side by 95 it's just now getting here but looks ominous to the east.


Member Since: October 18, 2005 Posts: 4 Comments: 3052
572. IKE
Quoting VAbeachhurricanes:


so based off one model run? cmon ike you know how much they change...


Here's what he asked....

"Quoting Rgraham:
OK, what are the chances, based on the latest GFS model, that Danny will come ashore at Hatteras Saturday night?".....

based on the latest run of the GFS, it has Danny going east of NC.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
cmc was as close as you can get with bill...even in the 5 day and everyone knows you shouldn't listen to anything past a 3 day
Member Since: Posts: Comments:
569. IKE
Quoting pearlandaggie:
doesn't CMC stand for "Can't Model Crap"? has this model's performance been better this year?


It's been better than it was in 2008, but...it spins Danny as a significant cane going just east of NC. Just can't see it being that strong. Maybe it'll prove me wrong.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
the differences are in how each computer model reads the troughs, how strong they are, how strong or weak they THINK they will be when the get to the coast, etc...basically, different computers = different scenerios
Member Since: Posts: Comments:
Quoting pearlandaggie:
doesn't CMC stand for "Can't Model Crap"? has this model's performance been better this year?


yeah, its been altered
Member Since: Posts: Comments:

Viewing: 617 - 567

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19Blog Index

Top of Page

About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

Local Weather

Mostly Cloudy
62 °F
Mostly Cloudy