Tropical Storm Danny likely to be named today

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

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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

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Is SeaStep here? Was asking about the SFMR and shallow water last night.

The SFMR is known to have a high bias when the water depth is less than 30 M and to have a low bias with very high rain rates. They are both correctable...I think (maybe just the rain fall-effected data)...but aren't as of yet. Always tweaking the obs...

A good paper detailing it: www.nhc.noaa.gov/jht/05-07reports/JHT07_Carswell_midyear.pdf

Neither of these has to do with water in the air but with the effect of both circumstances on foaming on the water surface.
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Quoting Acemmett90:

actully it relitivly normal becuase the last few year have been above normal


True. The 50 year average is 10 named (correct me if I'm wrong). Certainly a slow start, and most of the "predicters" call for slightly below average. Guess it really depends on if one gets hit. If you get hit, it's busy.
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The key near term model run will be this evenings 00Z. The Gulfstream IV will be releasing dropsondes in this pattern this afternoon.





Latest Recon Plan of the Day

000
NOUS42 KNHC 261745
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NTIONAL HURRICANE CENTER, MIAMI, FL.
0145 PM EDT WED 26 AUGUST 2009
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 27/1100Z TO 28/1100Z AUGUST 2009
TCPOD NUMBER.....09-090

I. ATLANTIC REQUIREMENTS
1. TROPICAL STORM DANNY
FLIGHT ONE - TEAL 70
A. 27/1800Z
B. AFXXX 0505A DANNY
C. 27/1430Z
D. 27.4N 74.1W
E. 27/1700Z TO 27/2130Z
F. SFC TO 10,000 FT

FLIGHT TWO - NOAA 49
A. 28/0000Z
B. NOAA9 0605A DANNY
C. 27/1730Z
D. NA
E. NA
F. 41,000 TO 45,000 FT

FLIGHT THREE - TEAL 71
A. 28/0600Z
B. AFXXX 0704A CYCLONE
C. 28/0230Z
D. 29.1N 74.8W
E. 28/0500Z TO 28/0930Z
F. SFC TO 10,000 FT

2. OUTLOOK FOR SUCCEEDING DAY: 6-HRLY FIXES
BEGINNING AT 28/1800Z.

3. REMARKS: NOAA WILL CONTINUE FLYING RESEARCH MISSIONS
EVER 12 HRS ON DANNY THROUGH 28/0800Z.

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Quoting JupiterFL:


Could they at least use a stencil of some sort to make the circle round. It looks like shakes the clown drew it.


The guy that writes those has his bowling league on Tuesday nights. he struggles on Wednesday's.
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Quoting JupiterFL:


That scenario, for Boston, would not be pretty.


Very similar to what Bob did. Bob hit Rhode Island hardest, here on Cape we got East side. This scenario gives RI west side, Cape East and watch out Boston.
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numbers don't matter anymore if ONE big one hits and people die tho...just saying
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661. IKE
Quoting mikatnight:


Your purple picture doesn't do you justice...


I liked the picture of herself she used as her avatar a couple of years ago.

Now I'm really in the gutter.

Back to Danny....

Member Since: June 9, 2005 Posts: 23 Comments: 37860
NO matter how crappy danny looks now, once we gets in to the gulf stream, even for just a little while, he will develop more.
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Quoting OSUWXGUY:
Looks to me like the CoC with Danny is really slowing to a crawl, and also appears to be stretching east to west, becoming more oval. Would be good if he stalls and doesn't get any further west...

Danny RGB Loop


If he does... then GFS would be pretty much the model to follow on this one as on the next update it should be to the right of the forecasted point.
Member Since: August 14, 2008 Posts: 4 Comments: 5038
With the GFDL, HWRF, and the CMC all showing Cat 2-3 canes based on the new data, the NE should be on high alert.
Member Since: August 14, 2008 Posts: 0 Comments: 137
653. IKE
Quoting Nickelback:
Here's the thing about Danny...There are no Storms to the West of its COC. Most of the Storms are on its northeast side. So Even though Danny may make a Slight NC landfall most likely it would bring little Rain due to the fact there are no storms on its east side..Am I right?


True....IF it stays that way.
Member Since: June 9, 2005 Posts: 23 Comments: 37860
Nothing to watch in the GOMEX.
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Quoting jasoniscoolman10:
here we go again.

looks like a tilted W
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Quoting IKE:


LOL...omg...great numbers.:)))))))))))

Now you've got my mind where it doesn't belong. Thanks NRA!
forget danny, i want these coordinates coming my way..;))))
Member Since: August 18, 2009 Posts: 0 Comments: 157
Quoting Nickelback:
Here's the thing about Danny...There are no Storms to the West of its COC. Most of the Storms are on its northeast side. So Even though Danny may make a Slight NC landfall most likely it would bring little Rain due to the fact there are no storms on its east side..Am I right?


No storms on W side yet....
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Quoting jasoniscoolman10:
here we go again.


Could they at least use a stencil of some sort to make the circle round. It looks like shakes the clown drew it.
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Looks to me like the CoC with Danny is really slowing to a crawl, and also appears to be stretching east to west, becoming more oval. Would be good if he stalls and doesn't get any further west...

Danny RGB Loop
In the GOM....off the west coast of Florida really starting to flare up storms, which are typical. Will be interesting to keep watching though.

Also keeping an eye on the wave off of Africa.
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Wow, too many people think like me here. I mentioned the Cone of Silence just the other day... hmmm

Thanks for beautiful link. It may not have a certificate but it sure is purty!

Can't get the Jet Stream map to load for US on main page, but it looks like the high pressure system controlling our weather right now is stalled. Is Danny s'posed t ride up the right side of the stalled high pressure system, or is this front going to move before Danny, stalling him and giving him time to get a little stronger, and then have him ride the left side, causing him to stay more to the left and come up and shake my hand, or at least my trees?
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Quoting Acemmett90:

lol no we mean the normal daily thunderstorms in fl


yes i know..being sarcastic, some of the afternoon storms here are much stronger that what danny is producing..
Member Since: August 18, 2009 Posts: 0 Comments: 157
Quoting OSUWXGUY:


Yeah. I just checked the max surface winds and despite the low pressure, the winds were only 72knots - Cat 1. Still bad, but damage gets exponentially worse as you go from 70 to 80 or 90 knots winds...especially in New England with a lot of old growth trees.


Thats not too bad and probably more realistic. I wonder how fast he would be moving at that time.
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Quoting NRAamy:
It wasn't me. I've had 10-4-2 as my numbers since late June.

I've had 36 - 24 - 36 since I was 18....how do I rank?


Link Please
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When will Danny enter the gulf stream? Isnt that where they expect it to develop even more?
Member Since: August 19, 2006 Posts: 13 Comments: 16215
There we go... we have possible TC development from the CV wave. UKM, GFS, and NOGAPS are hinting on it and now NHC has officially marked it with a yellow circle (<30%).
Member Since: August 14, 2008 Posts: 4 Comments: 5038
Quoting Acemmett90:

at 3pm like clock work lol


i guess SFLA will finally get danny by 3:00 than..;)
Member Since: August 18, 2009 Posts: 0 Comments: 157
Here's the thing about Danny...There are no Storms to the West of its COC. Most of the Storms are on its northeast side. So Even though Danny may make a Slight NC landfall most likely it would bring little Rain due to the fact there are no storms on its east side..Am I right?
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Quoting JupiterFL:


That scenario, for Boston, would not be pretty.


Yeah. I just checked the max surface winds and despite the low pressure, the winds were only 72knots - Cat 1. Still bad, but damage gets exponentially worse as you go from 70 to 80 or 90 knots winds...especially in New England with a lot of old growth trees.
not seeing danny pull a bill...bill was bigger and stronger at this point of the game...could be steered by the upper level troughs... danny doesn't have the stacking that bill had to be steered so early on...still saying he is gonna be more west of the general concesus...closer to the cmc...if not even more west
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It wasn't me. I've had 10-4-2 as my numbers since late June.

I've had 36 - 24 - 36 since I was 18....how do I rank?
Member Since: January 24, 2007 Posts: 317 Comments: 31946
Quoting jasoniscoolman10:
here we go again.


the way that wave looks..the crayon is wrong..they need to buy a red one.
Member Since: August 18, 2009 Posts: 0 Comments: 157
Quoting OSUWXGUY:


The HWRF produces a 947mb Cat 3/4 Beast as usual...and just grazes Cape Cod and extreme Northeast Maine with winds.

The GFDL takes a 965 Cat 2 through Rhode Island with the right front quadrant into eastern Massachusetts including Boston.

Hopefully Danny stays East...


That scenario, for Boston, would not be pretty.
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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


It is a slow season, isn't it? 8-4-2 still my guess...
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Quoting IKE:
12Z GFDL


12Z HWRF


The HWRF produces a 947mb Cat 3/4 Beast as usual...and just grazes Cape Cod and extreme Northeast Maine with winds.

The GFDL takes a 965 Cat 2 through Rhode Island with the right front quadrant into eastern Massachusetts including Boston.

Hopefully Danny stays East...
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.

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