Tropical outlook for July

By: Dr. Jeff Masters , 2:06 PM GMT on June 30, 2006

Share this Blog
0
+

A new area of disturbed weather has formed in the extreme southwestern Gulf of Mexico, near the coast of Mexico. The thunderstorm activity has little organization, and strong upper-level winds from the west are creating 15-25 knots of wind shear over the system. Wind shear is expected to remain 15 knots or higher for at least the next two days, making it unlikely for this disturbance to develop. The disturbance will move slowly northwest and bring welcome heavy rains to South Texas and Northeast Mexico over the weekend. Extreme drought conditions prevail there, but flash flooding may be a concern nevertheless.


Figure 1. Model forecast tracks of the tropical disturbance in the Gulf of Mexico.

Tropical wave in the Caribbean and Bahamas
The tropical wave in the eastern Caribbean we've been watching this week is just barely visible as a line of showers moving across Hispaniola towards Cuba and the Bahama Islands. Strong upper-level winds should continue to prohibit development of this wave over the Caribbean. However, the northern portion of this wave, now located north of Hispanolia and the easternmost Bahama Islands, is kicking up an impressive area of deep thunderstorms this morning. Wind shear is a high 20 knots over this disurbance, but the disturbance is moving northwest towards an area of lower wind shear. This may allow for some slow organization today before increased wind shear over the weekend tears this system apart. The disturbance is not a threat to land, as it is expected to recurve to the north and northeast around the Bermuda High.

Are we due for a repeat of the Hurricane Season of 2005?
That's the question on everyone's minds as we hit the end of the first month of hurricane season. After all, we've already had one tropical storm (Alberto) that occurred about the same time as last year's first storm (Arlene), and we almost had a second tropical storm near North Carolina this week, which would have made June 2006 match the June 2005 total of two tropical storms. Let's take a look at the large-scale weather patterns over the Atlantic and compare June 2005 with June 2006.

A look at June 2005
In Figure 2, we see the sea surface temperature (SST) and surface pressure departure from normal for June 2005. June SSTs were 1-2 C above normal, and June pressures were much below normal over almost the entire North Atlantic. The pressure at the center of the Bermuda High was 5 mb below normal, and pressures over the Caribbean and tropical Atlantic were about 1 mb below normal. The force of the trade winds that blow across the ocean is governed by the pressure gradient between the center of the Bermuda High and the tropics. The greater the difference in pressure, the stronger the winds have to blow, in their effort to equalize the pressure. In June 2005, this pressure gradient was very weak, and thus the trade winds were much lighter than usual. Lighter winds meant less evaporation occured over the surface waters, and thus less evaporative cooling (loss of latent heat). Without the usual strong winds to cool the ocean, the waters were able to heat up to record warm levels.

A ridge of high pressure dominated the Eastern U.S. in June 2005, and this ridge of high pressure continued to dominate throughout the entire hurricane season. As a result, the jet stream stayed far to the north, keeping wind shear low over the Gulf of Mexico and Caribbean. This ridge also acted to steer hurricanes into the Gulf Coast.


Figure 2. Sea Surface Temperature departure from normal for June 2005 (left) and surface pressure departure from normal (right). The arrows show the departure of surface winds from normal. The Bermuda High had a central pressure 5 mb lower than normal, which meant that the winds circulating around the high were weaker than normal. Thus, the surface wind anomaly arrows plotted above appear to rotate counterclockwise around the Bermuda High. Image credit: "The 2005 hurricane season: An echo of the past or a harbinger of the future?" Geophysical Research Letters, 33, March 2006.

A look at June 2006
An opposite trend in surface pressures occurred in June 2006, compared to June 2005 (Figure 3). The Bermuda High has averaged 7 mb stronger than normal this month--and a full 12 mb stronger than last year's June Bermuda High. Low pressure has dominated the Eastern U.S., thanks to a persistent dip in the jet stream that has brought rain, floods, and relatively cool weather to the Eastern U.S. This dip in the jet stream has also brought much higher levels of wind shear to the Gulf of Mexico and Caribbean than we saw last year in June.


Figure 3. Surface pressure departure from normal for June 2006. Note that surface pressures at the center of the Bermuda High were 7 mb above normal, and that pressures along the East Coast of the U.S. were below normal. Image credit: NOAA Climate Prediction Center.

As a result of the stronger Bermuda High this June, the trade winds blowing across the tropical Atlantic are much stronger than they were last year in June. These stronger winds have cooled the ocean, and SSTs are only 0.5 - 1.0 degrees C warmer than average this June, compared to 1 -2 degrees above normal in June 2005. This year's SST anomaly is still quite high, but probably not enough to support major hurricanes in July, like we saw last year with Dennis and Emily.


Figure 4. Sea surface temperatures and departures from normal (anomalies) for June 2006. SSTs are still 0.5 - 1 degrees C above normal over the tropical Atlantic, but still a full degree cooler than 2005. Image credit: NOAA Climate Prediction Center.

Outlook for July 2006
The two-week forecast from the GFS model continues to show the jet stream dipping over the Eastern U.S., and a stronger than normal Bermuda High. This pattern favors a continuation of the cool, rainy weather over the Northeast U.S., and hurricane strikes on Florida and the East Coast of the U.S.--or recurvature out to sea. The Gulf Coast has lower than average odds of a strike. This jet stream pattern should act to keep wind shear high over the main breeding grounds for July tropical cyclones--the Gulf of Mexico, Bahamas, and western Caribbean. If a hurricane does manage to develop and dodge the shear, it is unlikely it will become a major hurricane, due to the relatively cool ocean waters expected this July, compared to July 2005. Thus, July 2006 will not be a repeat of July 2005, which had five named storms, three hurricanes, and two intense hurricanes. If the current upper-level jet stream pattern holds in place, I think we can expect one or two named storms in July, one of them being a hurricane (not major). Will the current jet stream pattern hold? We are not very good at anticipating when these "blocking patterns" in the large scale atmospheric flow will change. Sometimes they can last for an entire season. If the pattern breaks in the last half of July, we could see more activity than I am forecasting here. In any case, I am still anticipating that August and September will be very busy again this year, so enjoy the relatively quiet start to hurricane season!

Have a great 4th of July weekend everyone, and I'll be posting daily updates.

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: 512 - 462

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11Blog Index

512. IKE
2:24 PM GMT on July 01, 2006
ST writes like he was serious with the gulf blob. I thought he had more knowledge about tropical systems....or maybe someone spiked his punch.

I guess his 8 am update got delayed???
Member Since: June 9, 2005 Posts: 23 Comments: 37860
511. weatherboyfsu
1:38 PM GMT on July 01, 2006
Good Morning everyone...........

That stormtop stuff is hilarious....Thats the funniest thing ive seen on here....

As for the Tropics, theres alot of teasing going on but nothing solid. So everyone have a great holiday weekend...........peace out!
Member Since: July 17, 2005 Posts: 0 Comments: 1025
510. Lane
1:16 PM GMT on July 01, 2006
We can't handle another hurricane in southeast Louisiana for sure, but we sure could use some rain. Hopefully we will get some rain out of the wave thats in the gulf
509. earthlydragonfly
1:15 PM GMT on July 01, 2006
Morning all. Looks good out. Hopefully we will have a nice quite day for the Shuttle to launch!
Member Since: July 1, 2005 Posts: 10 Comments: 1683
508. SAINTHURRIFAN
1:13 PM GMT on July 01, 2006
fl weather go enjoy yyour sat he only way this develops is
if it persist for another 48 hrs when the sheer is
forcast to lessen in the gulf shear is blowing everything east
of course you can wait for a lenny update lol and by the way he is late
Member Since: August 20, 2005 Posts: 5 Comments: 709
507. FLweather
1:02 PM GMT on July 01, 2006
Is the disorganized area in the gulf headed for the west coast of florida now?
Member Since: June 29, 2006 Posts: 0 Comments: 18
506. SAINTHURRIFAN
12:50 PM GMT on July 01, 2006
guys i wasnt going to post my ballad of lenny who is st
real name so call him lenny not stormtop, here is the ballad of
stormtop hope you like it my name is lenny my weather station is in
the toilet of jc penney, my meterology degree comes from the university
of not any my forecast and prediction values or worth a penny.
im know about weather as much as john goodman is skinny. i cant admit im
wrong because in a tight dress that belongs to jenny.i predict every storm
to hit the no dennys maybe i should meet and learn from my colleagues while
having a burger at wendys lol gulf system is nothing guys you are right
feel free to use this on old lenny when he needs it.
Member Since: August 20, 2005 Posts: 5 Comments: 709
504. StormJunkie
12:42 PM GMT on July 01, 2006
Morning all. Things seem to be pretty quite in the tropics this morning. 95L looks to just be pretty much dead, and 94L is just a disorganized mess. Still a lot osf shear in both areas.

Anywho, stop by StormJunkie.com and check out the new Quick Links section. Find all of your tracking needs on one page with this new area of the site. The rest of the site still has all of the models, imagery, marine data, wind data, and more that you need to stay ahead of the storm. There is also some nice WU blogger video here as well.

Ya'll have a great day. I'll check in on our invests later, although I think they are mostly done for.

SJ
Member Since: August 17, 2005 Posts: 26 Comments: 16874
502. MZT
12:10 PM GMT on July 01, 2006
Despite the cloudiness, pressures do seem a bit high this morning. 1016 MB or better at most stations. Maybe I will get some useful things done today -- not much to blog about.
Member Since: September 24, 2005 Posts: 0 Comments: 793
501. MZT
12:03 PM GMT on July 01, 2006
The daybreak limb is about to cross the Gulf, should be getting better visibles pretty soon
Member Since: September 24, 2005 Posts: 0 Comments: 793
498. pcolabob
11:07 AM GMT on July 01, 2006
is the area of showers south of La. moving towards al/fl panhandle we sure could use the rain
Member Since: August 3, 2011 Posts: 0 Comments: 0
497. BigToe
11:04 AM GMT on July 01, 2006
GTG folks, See you in the funny papers
Member Since: June 12, 2006 Posts: 0 Comments: 239
496. BigToe
10:50 AM GMT on July 01, 2006
Ike, Where you from? I,m from. Columbia SC. Heading to Myrtle Beach for the week
Member Since: June 12, 2006 Posts: 0 Comments: 239
495. mattrix
10:45 AM GMT on July 01, 2006
AC DUKE:
It all started in 1915 when Ernest Kouwen-Hoven moved to Melbourne and purchased a strip of beachside land lying between the Indian River and the Atlantic Ocean. He envisioned this property as becoming an exclusive beachside resort and indeed it did. This one-square mile became known as "Indialantic-by-the-Sea" The first map of this area was recorded in 1916.

Back then the only means of access to Indialantic was by boat or ferry. In 1919 Kouwen-Hoven began construction of a wooden bridge across the Indian River from Melbourne to Indialantic. It became known as the "Kouwen-Hoven's Folly" because of predictions it would never be completed. Kouwen-Hoven financed the construction by issuing his own bonds at 8% interest and using his land in Indialantic as an incentive for prospective buyers. If a person purchased a $100.00 bond, he could buy a lot for $20.00. The bridge was finally completed in 1921 and used for many years. Lighted by kerosene lanterns, the bridge was often set afire when they were blown or knocked over. It was not uncommon for drivers to travel with hammers to pound loose nails back into the wooden planks.

In 1941, a new concrete and steel swing bridge was begun. Construction, delayed with the onset of World War 11, was completed in 1947. This bridge was used until the existing high-rise was completed in 1985.

A stable community of homeowners was established in Indialantic during the Florida real estate boom that reached its peak in 1925. The 1.05-square mile area was incorporated in 1952 with a population of 1,500. It is today a quiet, primarily residential Town with a population of 2,844. Strict zoning codes and enforcement of these codes keep Indialantic a unique and prestigious community. Even though a large portion of the population is retired, there is still a diversity of residents consisting of young couples with children, professionals, business people, artists and students.

Indialantic stores and businesses cater to all the basic needs plus more exotic demands. Restaurants vary from fast food and family establishments to ethnic and gourmet dining. Residents and tourists can enjoy the public beach area from Miami to Watson. Swimming, fishing, boating and surfing are favorite pastimes. Threatened and endangered sea turtles nest along the shore from May through October. The recently refurbished boardwalk offers a place to stroll along the ocean and the parks throughout the Town provide getaways from the day's routine.

Designated a bird sanctuary in 1975 by a Town Council proclamation, the Town has taken measures to protect its abundance of animal species and plant life. Indialantic remains a natural, unspoiled paradise

494. IKE
10:35 AM GMT on July 01, 2006
This years best word in the tropics....SHEAR.

I hope it continues.
Member Since: June 9, 2005 Posts: 23 Comments: 37860
493. BigToe
10:33 AM GMT on July 01, 2006
Subtropical jet shear from Brownsville TX to Sarasota FL is keeping a lid on Campeche development. Sorry ST, no fun today
Member Since: June 12, 2006 Posts: 0 Comments: 239
492. IKE
10:20 AM GMT on July 01, 2006
Looking at what the NHC says this morning...nothing is going to form today. Looking at a satellite, I can see why they think so.
Member Since: June 9, 2005 Posts: 23 Comments: 37860
491. IKE
10:17 AM GMT on July 01, 2006
Some of these posts on here have me scratching my head. It's like you're wishing for something to form.

And ST.....uh...just forget it........
Member Since: June 9, 2005 Posts: 23 Comments: 37860
490. BigToe
10:12 AM GMT on July 01, 2006
I just think ST has become Bi-Polar. He's finally flipped. Too much pressure being a one man WX office. Funny as heck though.
Member Since: June 12, 2006 Posts: 0 Comments: 239
489. quakeman55
8:19 AM GMT on July 01, 2006
Just when I thought things couldn't get any more interesting with Stormtop...
Member Since: March 31, 2002 Posts: 1 Comments: 1276
488. Fshhead
7:47 AM GMT on July 01, 2006
LOL too funny!!!!!!!!!!!!!!!!!
Member Since: November 19, 2005 Posts: 9 Comments: 9960
487. ST0RMT0PSmom
7:38 AM GMT on July 01, 2006
STORMTOP IVE TOLD YOU NOT TO POST ON HERE YOU NAUGHTY SON! I WILL HAVE PAPA STORMTOP DEAL WITH YOU AS SOON AS I RUN YOUR COMPUTER OVER WITH MY CAR.
484. TampaCat5
7:26 AM GMT on July 01, 2006
I'm just kidding jp about the cessna thing, but stormtop is clueless, and you should basically ignore him.
Member Since: June 11, 2006 Posts: 4 Comments: 445
483. ST0RMT0PSmom
7:25 AM GMT on July 01, 2006
STORMTOP IM GOING TO SPANK YOU, YOU BAD BOY. IVE RAISED YOU LIKE A BABY ALL YOUR LIFE. HIS OFFICE IS IN HIS SANDBOX FOLKS. THIS HAS BEEN AN OFFICIAL STORMTOP SPANKING....HEADER 001236


Posted By: STORMTOP at 4:54 AM GMT on July 01, 2006.
THIS IS A SPECIAL WEATHER STATEMENT ISSUED BY THE STORMTOPS WEATHER OFFICE AT MIDNIGHT CDT...THE DISTURBANCE LOCATED ABOUT 400 MILES SOUTH OF LAFAYETTE LOUISIANA HAS BECOME MORE CONCENTRATED AND THE SPIRAL RAIN BANDS ARE BEGINNING TO WRAP AROUND THE MLC...WIND SHEAR HAS LESSENED SINCE YESTERDAY AND PRESSURES ARE STILL FALLING IN THE NORTH CENTRAL GULF TONIGHT...SATELLITE PICS IN THE LAST FEW FRAMES INDICATE THE MLC IS WORKING ITSELF DOWN TO THE SURFACE...AND AIRFORCE RECON PLANE IS SCHEDULED TO INVESTIGATE THE SYSTEM SATURDAY EVENING UNLESS CONDITIONS WARRANT AND EARLIER FLIGHT...THE SYSTEM HAS THE POTENTIAL TO STRENGHTEN ONCE IT REACHES TROPICAL DEPRESSION STATUS...THE SSTs ARE VERY WARM IN THIS PART OF THE GULF TONIGHT...ALL INTERESTS ALONG THE NORTHERN GULF SHOULD MONITOR THE PROGRESS OF THIS SYSTEM IN CASE IT DEVELOPS INTO A TROPICAL DEPRESSION OVER THE HOLIDAY WEEKEND...THE NEXT STATEMENT WILL BE ISSUED BY MY OFFICE AT 8AM CDT UNLESS CONDITIONS WARRANT AND EALIER RELEASE..........000012
481. TampaCat5
7:22 AM GMT on July 01, 2006
Stormtop is a dedicated amateur. He flies out each day in a Cessna with a barometer to measure pressures in the gulf. If he says the pressures are falling, their falling! However, I don't think he accounts for pressure altitude. So every time he goes up in his Cessna the pressure falls(due to his rising altitude). Someone may want ot clue him into this.
Member Since: June 11, 2006 Posts: 4 Comments: 445
477. TampaCat5
6:26 AM GMT on July 01, 2006
Late July the shear will die down, maybe the Bermuda high will weaken and the low pressure area over New England will move west, than we will have something to watch. Right now... nuthin!
Member Since: June 11, 2006 Posts: 4 Comments: 445
476. TampaCat5
6:24 AM GMT on July 01, 2006
I used to think ST was entertaining, now I think he is just insane.
Member Since: June 11, 2006 Posts: 4 Comments: 445
475. ForecasterColby
6:21 AM GMT on July 01, 2006
Rofl STORMTOP, I love how you append the numbers so you can feel like a big bad NWS forecaster :P
474. Skyepony (Mod)
5:35 AM GMT on July 01, 2006
94L* tired...nite ya'll.
Member Since: August 10, 2005 Posts: 226 Comments: 39441
473. Skyepony (Mod)
5:33 AM GMT on July 01, 2006
Beachside view is great, not like being on KSC, but less traffic. But it's pretty expensive to get on there anymore & no more family passes for the employees:(. I saw at least my 1st dozen or so from there. Guess we didn't realize the dangers when they 1st started sending them up. This will be the 115th space shuttle launch, I've seen near everyone live from outside.

Acduke yeah I'm in Melbourne. Planned your vacation well, weather wise.

The last few frames do look a little better on L94. If that shear lets up maybe it will hold it's convection & we'll have launch worthy weather.
Member Since: August 10, 2005 Posts: 226 Comments: 39441
472. earthlydragonfly
5:20 AM GMT on July 01, 2006
goodnight all. gotta hit the rack.. nice talking to yall!
Member Since: July 1, 2005 Posts: 10 Comments: 1683
471. earthlydragonfly
5:17 AM GMT on July 01, 2006
Now I will be at Dixie Crossroads launch or no launch for dinner.
Member Since: July 1, 2005 Posts: 10 Comments: 1683
470. acduke
5:11 AM GMT on July 01, 2006
Skyepony-

You mean Indialantic? I don't know why they spell it that way...weird. My grandparents have a condo there on A1A. Should be going down for Christmas. Are you in Melbourne? If you go to Titusville, get some Dixie Crossroad's for me...yumm! Anyway, we watched the NASA "Deep Impact" launch from Indialantic in January 2005, and headed up to the cape back in 2000 or 2001 for the shuttle Atlantis launch.

If any of you have never seen the shuttle launch and can...GO! It is one of the most exciting things I've ever witnessed. When that thing fires up and the sound waves hit you in the chest and nearly knock you over, and all the car alarms are going off...there's nothing like it in the world!! It was twilight before sunrise, and it rose like a fiery sun, turning into a shimmering star, leaving a trail behind it that broke into the sunlight through bright blues, oranges, yellows, and whites. I almost cried...it was a religious experience, lol. Hooked me on astronomy for life. You know I got a big fat A in AST 115 last semester!
469. earthlydragonfly
5:09 AM GMT on July 01, 2006
just the condo beach side
Member Since: July 1, 2005 Posts: 10 Comments: 1683
468. STORMTOP
5:09 AM GMT on July 01, 2006
THIS IS A SPECIAL WEATHER STATEMENT ISSUED BY THE STORMTOPS WEATHER OFFICE AT MIDNIGHT CDT...THE DISTURBANCE LOCATED ABOUT 400 MILES SOUTH OF LAFAYETTE LOUISIANA HAS BECOME MORE CONCENTRATED AND THE SPIRAL RAIN BANDS ARE BEGINNING TO WRAP AROUND THE MLC...WIND SHEAR HAS LESSENED SINCE YESTERDAY AND PRESSURES ARE STILL FALLING IN THE NORTH CENTRAL GULF TONIGHT...SATELLITE PICS IN THE LAST FEW FRAMES INDICATE THE MLC IS WORKING ITSELF DOWN TO THE SURFACE...AND AIRFORCE RECON PLANE IS SCHEDULED TO INVESTIGATE THE SYSTEM SATURDAY EVENING UNLESS CONDITIONS WARRANT AND EARLIER FLIGHT...THE SYSTEM HAS THE POTENTIAL TO STRENGHTEN ONCE IT REACHES TROPICAL DEPRESSION STATUS...THE SSTs ARE VERY WARM IN THIS PART OF THE GULF TONIGHT...ALL INTERESTS ALONG THE NORTHERN GULF SHOULD MONITOR THE PROGRESS OF THIS SYSTEM IN CASE IT DEVELOPS INTO A TROPICAL DEPRESSION OVER THE HOLIDAY WEEKEND...THE NEXT STATEMENT WILL BE ISSUED BY MY OFFICE AT 8AM CDT UNLESS CONDITIONS WARRANT AND EALIER RELEASE..........000012
467. Skyepony (Mod)
5:00 AM GMT on July 01, 2006
I probibly won't make it that close for the shuttle on the pad pic tommarrow. Though I've seen a night photo like that. How about you Dragonfly, got a close spot picked?
Member Since: August 10, 2005 Posts: 226 Comments: 39441
466. earthlydragonfly
4:55 AM GMT on July 01, 2006
definitley that pic could top a launch......

launch 4 pm
Member Since: July 1, 2005 Posts: 10 Comments: 1683
465. Skyepony (Mod)
4:53 AM GMT on July 01, 2006
Launch window opens at 3:49pm est. This last week our near daily east coast showers have been late arrivers. So maybe we can get lucky. NHC doesn't actually call it. It's predevised, lightning with in 20 miles with in last hour, winds at different hieghts so long before launch & etc. The NASA Mets stare at the radar & data as does the local reporters. More than once in the last 10 minutes the local news will say that gust was too high, oh 1 rouge lightning strike, it'll be scrubbed, 2 mins later the offical scrub.
Member Since: August 10, 2005 Posts: 226 Comments: 39441
463. rwwhot
4:38 AM GMT on July 01, 2006
If the shuttle doesn't go, you might be able to get images of the shuttle with lightning nearby. Not what you're looking for, but could be quite cool as an art photo...
Member Since: September 20, 2005 Posts: 0 Comments: 3
462. Skyepony (Mod)
4:35 AM GMT on July 01, 2006
I have shuttle photo plans as well. Don't know if I'm going across the causeway to Indiatlantic or if I'll end up in Titusville on US1. Really hope we have a good launch tommarrow.
Member Since: August 10, 2005 Posts: 226 Comments: 39441

Viewing: 512 - 462

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11Blog 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.

JeffMasters's Recent Photos

Lake Effort Snow Shower Over Windsor, Ontario
Sunset on Dunham Lake
Pictured Rocks Sunset
Sunset on Lake Huron