July hurricane outlook

By: Dr. Jeff Masters , 7:26 PM GMT on July 02, 2009

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Atlantic tropical cyclone activity typically picks up a bit during the first half of July. Since the current active hurricane period began in 1995, seven of 14 years (50%) have had a named storm form during the first half of July. The busiest first half of July occurred in 2005, when three hurricanes formed. These included Hurricane Dennis and Hurricane Emily--the strongest hurricanes ever observed so early in the season. As seen in Figure 1, most of the early July activity occurs in the Gulf of Mexico, Western Caribbean, and Carolina waters. However, a few long-track "Cape Verdes" hurricanes begin to occur. These are spawned by tropical waves that come off the coast of Africa. Tropical waves serve as the instigators of about 85% of all major hurricanes. Last year's Hurricane Bertha was one such rare early July Cape Verdes hurricane. Bertha's 120 mph winds made it the sixth strongest early-season Atlantic hurricane on record. Bertha also set the record for farthest east formation as a tropical storm, hurricane, and major hurricane, so early in the season.


Figure 1. Tracks of all tropical storms and hurricanes 1851 - 2006 that formed July 1-15. North Carolina and the Gulf of Mexico coast from the Florida Panhandle to Texas are the preferred strike locations. Oddly, the Florida Peninsula has been struck by only two storms that formed in the first half of July.

Sea Surface Temperatures
Sea Surface Temperatures (SST) anomalies have warmed slightly over the past two weeks, but are close to average over the tropical Atlantic between Africa and Central America (Figure 2). These are the are the coolest SST anomalies we've seen since 1994. The strength of the Azores-Bermuda high has been near average over the past two weeks, driving near-average trade winds. Stronger-than-average trade winds were observed through most of the period November 2008 - May 2009, which helped cool the tropical Atlantic substantially. Strong winds mix up colder water from the depths and cause greater evaporative cooling. The latest 2-week run of the GFS model predicts continued average-strength trade winds through mid-July, so SSTs should remain near average during this period.

Typically, July tropical storms form over the Gulf of Mexico, Western Caribbean, and Gulf Stream waters just offshore Florida. SSTs are about 1.0°C above average for this time of year in the Gulf of Mexico, but near average elsewhere. July storms typically form when a cold front moves off the U.S. coast and stalls out, with the old frontal boundary serving as a focal point for development of a tropical disturbance. There will be one or two fronts moving off the U.S. coast over the next two weeks, and we will need to watch these for development. Wind shear is too high and SSTs are usually too cold in July to allow African tropical waves to develop into tropical storms. African tropical waves serve as the instigators of about 85% of all major hurricanes,

Figure 2. Sea Surface Temperature (SST) departure from average for July 2, 2009. SSTs were near average over the tropical Atlantic's Main Development region for hurricanes, from Africa to Central America between 10° and 20° North Latitude. Note the large region of above average SSTs along the Equatorial Pacific off the coast of South America, the hallmark of a developing El Niño episode. Image credit: NOAA/NESDIS

El Niño
El Niño conditions continue to amplify over the tropical Eastern Pacific. Ocean temperatures there rose 0.5°C over the past two weeks, and are now 0.45°C above the threshold for El Niño, according to the Australian Bureau of Meteorology (Figure 3). NOAA's Climate Prediction Center issued an El Niño Watch in early June, saying "that conditions are favorable for a transition from neutral to El Niño conditions during June - August 2009". The pattern of changes in surface winds, upper-level winds, sea surface temperatures, and deeper water heat content are all consistent with what has been observed during previous developing El Niños, and latest set of mid-June runs of the El Niño computer models are almost universally calling for El Niño conditions to become well-established for the peak months of hurricane season, August - October. It is likely that Atlantic hurricane activity will be suppressed in 2009 due to the strong upper-level winds and resulting wind shear an El Niño event usually brings to the tropical Atlantic.


Figure 3. Sea Surface Temperature (SST) departure from average for the the equatorial Eastern Pacific (the area 5°N - 5°S, 120°W - 170°W, also called the "Niña 3.4 region"). El Niño conditions exist when the SST in this region rises 0.5°C above average. As of June 28, 2009, SSTs in the Niño 3.4 region had risen to 0.95°C above average. To be considered an "El Niño episode", El Niño conditions must occur for five consecutive months, using 3-month averages. Image credit: Australian Bureau of Meteorology.

Wind shear
Wind shear is usually defined as the difference in wind between 200 mb (roughly 40,000 foot altitude) and 850 mb (roughly 5,000 foot altitude). In most circumstances, wind shear above 20 knots will act to inhibit tropical storm formation. Wind shear below 12 knots is very conducive for tropical storm formation. High wind shear acts to tear a storm apart. The jet stream's band of strong high-altitude winds is the main source of wind shear in July over the Atlantic hurricane breeding grounds, since the jet is very active and located quite far south this time of year.

The jet stream over the past two months has been locked into a pattern where a southern branch (the subtropical jet stream) brings high wind shear over the Caribbean, and a northern branch (the polar jet stream) brings high wind shear offshore of New England. This often leaves a "hole" of low shear between the two branches off the coast of North Carolina, which is where Tropical Depression One formed at the end of May.

The jet stream is forecast (Figure 4) to maintain this two-branch pattern over the coming two weeks. This means that the waters offshore of the Carolinas are the most likely place for a tropical storm to form during this period.


Figure 4. Wind shear in m/s between 200 mb and 850 mb, as forecast by the 06Z July 02, 2009 run of the GFS model. The position and strength of the subtropical jet stream is forecast to change little over the next two weeks, and this jet will bring high wind shear to the Caribbean and Gulf of Mexico into mid-July. There will at times be a region of low shear between the polar jet (northern set of arrows on the plots) and the subtropical jet, allowing for possible tropical development off the coast of North Carolina. Wind speeds are given in m/s; multiply by two to get a rough conversion to knots. Thus, the red regions of low shear range from 0 - 16 knots.

Dry air and African dust
June and July are the peak months for dust coming off the coast of Africa, and the Saharan dust storms have been quite active over the past month. Expect dust from Africa to be a major deterrent to any storms that try to form between Africa and the Lesser Antilles Islands in July.

Steering currents
The steering current pattern over the past few weeks has not changed much, and is typical for June and July. We have an active jet stream bringing many troughs of low pressure off the East Coast of the U.S. These troughs are frequent enough and strong enough to recurve any tropical storms or hurricanes that might penetrate north of the Caribbean Sea. Steering current patterns are predictable only about 3 - 5 days in the future, although we can make very general forecasts about the pattern as much as two weeks in advance. At present, it appears that the coming two weeks will maintain the typical July pattern, bringing many troughs of low pressure off the East Coast capable of recurving any July storms that might form. There is no telling what might happen during the peak months of August, September, and October--we might be in for a repeat of the favorable 2006 steering current pattern that recurved every storm out to sea--or the unfavorable 2008 pattern, that steered Ike and Gustav into the Gulf of Mexico.

Summary
Recent history suggests a 50% chance of a named storm occurring in the first half of July. Given that none of the computer models are forecasting tropical storm formation in the coming seven days, and SST and wind shear patterns look pretty average, I'll go with a 20% chance of a named storm forming during the first half of July.

Vote for Mike Theiss as an Antarctica blogger
Extreme weather photographer Mike Theiss, who wrote our Ultimate Chase photography blog for two years until a new job took him to South America, wants your help. He's entering a Quark Expeditions competition to receive an expense-paid 2-week trip to Antarctica, where he will do some intensive photography and blogging. In order to go, he needs the votes to show that he's a popular blogger. So, if you liked his posts while he was blogging for wunderground, and want to see him blog for wunderground during this potential Antarctica voyage, go to http://www.blogyourwaytoantarctica.com/blogs/view /220 and cast a vote. It takes about 3 minutes navigate through the registration and voting process. Mike will be back chasing hurricanes this August, and has promised to post his excellent storm photos on wunderground should we help him secure the Antarctica gig.

Have a great holiday weekend, and I'll be back Monday with a new post.

Jeff Masters

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1196. AussieStorm
3:36 PM GMT on July 04, 2009
I remember Dr. Masters saying there is a higher chance of a storm developing in the GOMEX or off the coast of FLA. and N/S Carolina's this season
Member Since: September 30, 2007 Posts: 9 Comments: 15935
1195. AllStar17
3:36 PM GMT on July 04, 2009
Subtropical Storm Laura from last season (9/29/08)



Invest 92L from earlier this season. Confuses me why it was not named....especially since they named Laura last year.

Member Since: June 29, 2009 Posts: 13 Comments: 5313
1194. AussieStorm
3:35 PM GMT on July 04, 2009
Quoting IKE:


It could...then again there could be nothing in the GOM all season...look at 2006...one GOM system and that was in June...


Member Since: September 30, 2007 Posts: 9 Comments: 15935
1193. KEHCharleston
3:33 PM GMT on July 04, 2009
Quoting Weather456:
How is no tropical development a good thing? Isn't that main reason why we all here? I don't wish for a tropical storm to impact anyone but some good fish storms are always welcome to keep the blog alive.
Looking at the BIG picture, tropical storms are one of the self regulating mechanisms that Mom Nature has put into effect. Would hate to think of the stew we would be in without them.

ADDED: And I agree with 456 and others - they are fascinating to watch.
Also...Wishcasting and downcasting have no effect on storms, so it is not as if someone is practicing voodoo with their predictions.
Member Since: August 19, 2008 Posts: 6 Comments: 2490
1192. AllStar17
3:32 PM GMT on July 04, 2009
Quoting hurricaneseason2006:
Why are we here blogging between June 1 and November 30, to state things like?

The hurricane season is 17% over and may it continue

I predict 4 named storms

This season is a dud.

The GFS is forecasting nothing for the next two weeks and may it continue.


Of course not:

There is some reason why we gather here durring hurricane season.


Good point, and it is only July 4th, and some bloggers are calling this season a bust, very confusing to me.
Member Since: June 29, 2009 Posts: 13 Comments: 5313
1191. atmoaggie
3:31 PM GMT on July 04, 2009
Quoting AussieStorm:

Wouldn't the longer there is no storm mean that the SST's are allowed to get really high in the GOMEX(like bath water). Which would mean if there was a storm to enter or form in the GOMEX it would rapidly develop into a "monster"????


A few of the bigger storms have clouded over 3/4 of the Gulf...not to mention the water mixing that goes on with 30+ foot waves going on in 1/3 of it. I am sure the peak intensity of one would be limited by the presence of numerous storms over a season.
Member Since: August 16, 2007 Posts: 6 Comments: 12461
1190. AllStar17
3:31 PM GMT on July 04, 2009
Quoting AussieStorm:

Wouldn't the longer there is no storm mean that the SST's are allowed to get really high in the GOMEX(like bath water). Which would mean if there was a storm to enter or form in the GOMEX it would rapidly develop into a "monster"????


Yes. Which is why everyone should remain prepared, because if a storm were to have favorable conditions in hot, deep water, with high TCHP, it could rapidly intensify
Member Since: June 29, 2009 Posts: 13 Comments: 5313
1189. IKE
3:31 PM GMT on July 04, 2009
Quoting AussieStorm:

Wouldn't the longer there is no storm mean that the SST's are allowed to get really high in the GOMEX(like bath water). Which would mean if there was a storm to enter or form in the GOMEX it would rapidly develop into a "monster"????


It could...then again there could be nothing in the GOM all season...look at 2006...one GOM system and that was in June...

Member Since: June 9, 2005 Posts: 23 Comments: 37858
1187. AussieStorm
3:30 PM GMT on July 04, 2009
Quoting hahaguy:


Yes, the longer they sit they will get hotter.

Which is bad...very bad
Member Since: September 30, 2007 Posts: 9 Comments: 15935
1186. IKE
3:29 PM GMT on July 04, 2009
Quoting hurricaneseason2006:


I don't understand it myself. The main and always number 1 reason the blog is active is because of tropical cyclone development, and the same ones who are saying that it is good thing the tropics are quiet (IKE) are the same ones, who are hiding behind their boredom. I agree with Weather456 and what he said in May, I think:

Just like how storm chasers benefit from tornado development and a surfer benefits from large swells, a tropical weather amateur or professional actually is drawn to tropical cyclone development.



Boredom? I haven't been on here in almost 24 hours.

I'm glad there's nothing. I've got more important things to worry about like my health and the balance in my checking account...which is rather low.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
1185. hahaguy
3:28 PM GMT on July 04, 2009
Quoting AussieStorm:

Wouldn't the longer there is no storm mean that the SST's are allowed to get really high in the GOMEX(like bath water). Which would mean if there was a storm to enter or form in the GOMEX it would rapidly develop into a "monster"????


Yes, the longer they sit they will get hotter.
Member Since: August 12, 2007 Posts: 2 Comments: 2838
1184. AussieStorm
3:25 PM GMT on July 04, 2009
Quoting IKE:


For this blog....definitely worse.

For those on the planet...great news. No death and destruction.

Wouldn't the longer there is no storm mean that the SST's are allowed to get really high in the GOMEX(like bath water). Which would mean if there was a storm to enter or form in the GOMEX it would rapidly develop into a "monster"????
Member Since: September 30, 2007 Posts: 9 Comments: 15935
1182. CybrTeddy
3:22 PM GMT on July 04, 2009
Quoting AussieStorm:

Is the longer we go without a storm, better or worse?


Well in Andrew, Alex, and Antia's case worse.
Member Since: July 8, 2005 Posts: 259 Comments: 24018
1181. ackee
3:22 PM GMT on July 04, 2009
shear has been really stong thus far this seasons does that mean when el nino it will increase further
Member Since: July 15, 2008 Posts: 0 Comments: 1372
1180. IKE
3:21 PM GMT on July 04, 2009
Quoting AussieStorm:

Is the longer we go without a storm, better or worse?


For this blog....definitely worse.

For those on the planet...great news. No death and destruction.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
1179. atmoaggie
3:22 PM GMT on July 04, 2009
Member Since: August 16, 2007 Posts: 6 Comments: 12461
1178. IKE
3:20 PM GMT on July 04, 2009
Quoting extreme236:
img src="Image Hosted by ImageShack.us
" width="560" height="340" alt="" />


I know that view is kind of off to the side, but doesn't that look rather ill?
Member Since: June 9, 2005 Posts: 23 Comments: 37858
1177. KEEPEROFTHEGATE (Mod)
3:20 PM GMT on July 04, 2009

THE COUNT SO FAR

cpac basin
1 invest

epac basin
3 invests
1 hurricane

atl basin
4 invests
1 T.D.

Member Since: July 15, 2006 Posts: 171 Comments: 53827
1176. AussieStorm
3:19 PM GMT on July 04, 2009
Quoting Weather456:
How is no tropical development a good thing? Isn't that main reason why we all here? I don't wish for a tropical storm to impact anyone but some good fish storms are always welcome to keep the blog alive.

Is the longer we go without a storm, better or worse?
Member Since: September 30, 2007 Posts: 9 Comments: 15935
1175. cycloone
3:16 PM GMT on July 04, 2009
Quoting Weather456:
How is no tropical development a good thing? Isn't that main reason why we all here? I don't wish for a tropical storm to impact anyone but some good fish storms are always welcome to keep the blog alive.
I agree
Member Since: March 2, 2003 Posts: 65 Comments: 1009
1174. atmoaggie
3:16 PM GMT on July 04, 2009
The CIRA cyclogenesis folks are showing little divergence from climatology.

Member Since: August 16, 2007 Posts: 6 Comments: 12461
1173. IKE
3:16 PM GMT on July 04, 2009
Quoting KEHCharleston:
Stupid Question Time

Why does the shear continue to be high in the Caribbean and GOM?
El Nino is not yet firmly entrenched.


I think that's part of it, is El Nino.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
1172. extreme236
3:15 PM GMT on July 04, 2009
.
Member Since: August 2, 2007 Posts: 19 Comments: 19234
1171. IKE
3:15 PM GMT on July 04, 2009
Quoting KEEPEROFTHEGATE:
thats a good thing ike as long as it keeps showing nothing we have nothing to worry about


Exactly and I'm happy it shows nothing.

I've already mowed my back yard down to my dock..burned a dead tree in my pit...workin man'


Happy Bday America:)
Member Since: June 9, 2005 Posts: 23 Comments: 37858
1170. Dakster
3:13 PM GMT on July 04, 2009
Quoting tipsymcstagger:
Off subject:

Since June 15th, we (New Orleans) have had the hottest stretch of days I can remember for anytime of summer & not just June. We have set numerous daily records and the hottest temperature recorded EVER at 104 recorded at Audubon Park. I don't think that is our "official" weather station, but I am interested in seeing how many records have been tied or surpassed since 6/15. I cannot seem to find that info....probably because the heat has made me stupid.

Thanks in advance if you know where I can find that info.


In a purely unscientific comment, we broke an all time record high a couple of weeks ago in Miami and it seems a lot hotter, earlier than normal as well... Can't answer the where to find out "officially" though...
Member Since: March 10, 2006 Posts: 0 Comments: 10282
1169. extreme236
3:13 PM GMT on July 04, 2009
94L looks organized convective wise, but that center is still displaced away from that convection.
Member Since: August 2, 2007 Posts: 19 Comments: 19234
1168. bappit
3:12 PM GMT on July 04, 2009
1156, 1157

Awwww, c'mon guys ... it wasn't always naked. It's just naked now (again).
Member Since: May 18, 2006 Posts: 10 Comments: 6022
1167. atmoaggie
3:11 PM GMT on July 04, 2009
Quoting tipsymcstagger:
Off subject:

Since June 15th, we (New Orleans) have had the hottest stretch of days I can remember for anytime of summer & not just June. We have set numerous daily records and the hottest temperature recorded EVER at 104 recorded at Audubon Park. I don't think that is our "official" weather station, but I am interested in seeing how many records have been tied or surpassed since 6/15. I cannot seem to find that info....probably because the heat has made me stupid.

Thanks in advance if you know where I can find that info.


From our NWS WFO:

PUBLIC INFORMATION STATEMENT...CORRECTED
NATIONAL WEATHER SERVICE NEW ORLEANS LA
710 PM CDT WED JUL 1 2009

...JUNE DEEP SOUTH HEAT WAVE...

JUNE WAS A HOT RECORD BREAKING EVENT. DURING THIS STRETCH OF UNUSUAL
HEAT SOME LOCATIONS HAVE HIT THE CENTURY MARK WITH SOME SITES TYING
OR BREAKING THEIR JUNE ALL TIME RECORD MAX. IN ADDITION TO THE HEAT
IT HAS ALSO BEEN A VERY DRY MONTH ALTHOUGH A FEW SITES RECEIVED SOME
VERY MUCH NEEDED RAIN ON THE 28TH AND 29TH. BELOW ARE A FEW CHARTS
OF CLIMATE DATA FOR A FEW SITES AROUND THE AREA.

ASOS SITE IDENTIFIERS

MCB = MCCOMB AIRPORT (RECORDS BACK TO 1948)
BTR = BATON ROUGE(RYAN FIELD) (RECORDS BACK TO 1930)
MSY = NEW ORLEANS INT`L AIRPORT (RECORDS BACK TO 1946)
GPT = GULFPORT/BILOXI AIRPORT (RECORDS BACK TO 2000)
ASD = SLIDELL AIRPORT (RECORDS BACK TO 2000)
PQL = PASCAGOULA (RECORDS BACK TO 2000)


# OF 100 HIGHEST MAX
SITE DEGREE DAYS TEMP RECORDED

MCB 6 103
BTR 2 100(TWICE)
MSY 1 101
GPT 2 102
ASD 2 101
PQL 0 99(THREE TIMES)


DAILY RECORDS
BROKEN OR TIED

MCB 11 NEW MONTHLY RECORD MAX OF 103 ON THE 28TH
OLD RECORD OF 102 HAS OCCURRED 4 TIMES
ON THE 14TH IN 1963...THE 29TH IN 1969
THEN TWICE THIS MONTH...THE 23RD AND 25TH
BTR 3
MSY 6 NEW MONTHLY RECORD MAX OF 101 ON THE 24TH
OLD RECORD OF 100 SET ON THE 30TH IN 1954


MONTHLY AVG
TEMPERATURE

MCB 81.8 THE 3RD WARMEST JUNE ON RECORD
BTR 83.2 TIED FOR THE 3RD WARMEST JUNE ON RECORD
MSY 83.3 TIED FOR THE 5TH WARMEST JUNE ON RECORD
GPT 82.2
ASD 82.2
PQL 80.9

AVG MONTHLY
MAX TEMPERATURE

MCB 94.1 THE 2ND WARMEST JUNE ON RECORD
BTR 93.7 THE 5TH WARMEST JUNE ON RECORD
MSY 92.2 TIED FOR THE 5TH WARMEST JUNE ON RECORD
GPT 91.8
ASD 92.6
PQL 91.2

RAINFALL TOTALS

MCB 0.04" THE DRIEST JUNE ON RECORD
BTR 0.59" THE 4TH DRIEST JUNE ON RECORD
MSY 2.13" THE 8TH DRIEST JUNE ON RECORD
GPT 1.21"
ASD 1.70"
PQL 3.12"


JULY HAS ALREADY STARTED OFF ON THE WRONG FOOT WITH VERY WARM
TEMPERATURES BEING RECORDED ON TODAY AND IT LOOKS LIKE THESE WARM TO
HOT CONDITIONS WILL CONTINUE A LITTLE WHILE LONGER. THE MOSTLY DRY
WEATHER ALSO LOOKS TO PERSIST AT LEAST ANOTHER WEEK.

HIGHS TODAY ACROSS THE AREA

MCB 102 NEW RECORD
BTR 99
MSY 97
ASD 97
GPT 98
PQL 96


*** DATA USED FOR NEW ORLEANS AND BATON ROUGE WERE FROM THE MSY
AND BTR ASOS SITES SPECIFICALLY. WHEN THIS DATA IS COMPARED WITH
THE ENTIRE NEW ORLEANS AND BATON ROUGE AREA RECORD WHICH GOES
BACK FURTHER SOME OF THE RECORDS BROKEN WOULD NOT HAVE BEEN AND
THE RANKINGS WOULD ACTUALLY BE A FEW SPOTS LOWER. FOR THE
MISSISSIPPI COAST GPT AND PQL DO NOT GO BACK FAR ENOUGH FOR AN
OFFICIAL CLIMATE HISTORY BUT THERE IS A MORE EXTENSIVE RECORD FOR
THE GULFPORT AREA WHICH IS SHOWN BELOW FOR AT LEAST SOME COMPARISON
OF THIS RECENT HEAT WAVE AND DRY SPELL. ALSO BELOW IS BILOXI WHICH
HAS A LONG HISTORY AND SINCE IT IS SO LONG DID NOT APPEAR TO HAVE
AN EXTREME JUNE LIKE MOST OF OUR OTHER SITES.


GULFPORT AREA

INCLUDES GPT AND GULFPORT NAVAL CENTER(RECORDS BACK TO 1956)

4 DAILY RECORDS BROKEN OR TIED

NEW MONTHLY RECORD MAX OF 102 ON THE 23RD
OLD RECORD OF 99 HAS OCCURRED 6 TIMES

AVG TEMP 82.2 TIED FOR THE 6TH WARMEST JUNE ON RECORD
AVG MAX TEMP 91.8 THE 5TH WARMEST JUNE ON RECORD
RAINFALL 1.21 THE 6TH DRIEST JUNE ON RECORD


BILOXI
(RECORDS BACK TO 1893)

3 DAILY RECORDS BROKEN OR TIED

AVG TEMP 82.2 THE 14TH WARMEST JUNE ON RECORD
AVG MAX TEMP 89.8 TIED FOR THE 22ND WARMEST JUNE ON RECORD
RAINFALL 2.25 TIED FOR THE 24TH DRIEST JUNE ON RECORD

Member Since: August 16, 2007 Posts: 6 Comments: 12461
1166. nrtiwlnvragn
3:11 PM GMT on July 04, 2009
Quoting KEHCharleston:
Stupid Question Time

Why does the shear continue to be high in the Caribbean and GOM?
El Nino is not yet firmly entrenched.


Normal Climatology

Member Since: September 23, 2005 Posts: 14 Comments: 11161
1165. KEEPEROFTHEGATE (Mod)
3:10 PM GMT on July 04, 2009
Quoting AllStar17:



Looks like it shows 2 storms in the EPAC.
for this time of year we should of had 8 or 10 invests with 3 or 4 of them storms by now in epac we've had 3 invest with one being a storm way way down
Member Since: July 15, 2006 Posts: 171 Comments: 53827
1164. Cavin Rawlins
3:10 PM GMT on July 04, 2009
How is no tropical development a good thing? Isn't that main reason why we all here? I don't wish for a tropical storm to impact anyone but some good fish storms are always welcome to keep the blog alive.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
1163. AussieStorm
3:09 PM GMT on July 04, 2009
'150,000 flee' deadly China storms
Torrential rain battering southern China has forced more than 150,000 people from their homes, toppled hundreds of houses and punched a dangerous hole in the spillway of a dam, Xinhua news agency reported.

The destruction after just three days of downpours was a reminder of the havoc that parts of China may suffer during the wet summer months ahead.

The rain sweeping parts of Jiangxi province and Guangxi region has so far killed three people with four missing, Xinhua reported.

Many towns in Rongshui County, Guangxi, reported rainfall of up to 200 millimetres from Wednesday to Friday, said Xinhua, adding that more than 5,600 dwellings and buildings across Jiangxi collapsed under the downpours and resulting flooding.

In Jiangxi, more than 80,000 people were moved out of fear for their safety, and in Guangxi another 70,000 were moved. Often, Chinese officials moved people only short distances from flood-threatened areas.

State television news showed footage of locals and troops struggling to contain a breach from a flood diversion tunnel at the base of the Kama Dam in Luocheng County, Guangxi.

A 13.5 metre-long section gave way under the weight of the water and a nearby hillside was also in danger of collapsing. Local officials ordered more than 7,500 locals living downstream to flee, fearing the dam might crack.

The threat was intense enough that Chinese Premier Wen Jiabao issued orders to "ensure the safety of the public", Xinhua reported. By Saturday afternoon the danger was receding, a later report said.

But forecasters in Guangxi have said that torrential rain was likely to hit parts of the region again on Sunday.

- Reuters
Member Since: September 30, 2007 Posts: 9 Comments: 15935
1162. KEHCharleston
3:09 PM GMT on July 04, 2009
Stupid Question Time

Why does the shear continue to be high in the Caribbean and GOM?
El Nino is not yet firmly entrenched.
Member Since: August 19, 2008 Posts: 6 Comments: 2490
1161. AllStar17
3:06 PM GMT on July 04, 2009
Quoting IKE:
00Z ECMWF shows zilch in the Atlantic through the 14th of July.



Looks like it shows 2 storms in the EPAC.
Member Since: June 29, 2009 Posts: 13 Comments: 5313
1160. KEEPEROFTHEGATE (Mod)
3:03 PM GMT on July 04, 2009
Quoting IKE:
00Z ECMWF shows zilch in the Atlantic through the 14th of July.
thats a good thing ike as long as it keeps showing nothing we have nothing to worry about
Member Since: July 15, 2006 Posts: 171 Comments: 53827
1159. IKE
3:00 PM GMT on July 04, 2009
00Z ECMWF shows zilch in the Atlantic through the 14th of July.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
1158. tipsymcstagger
3:00 PM GMT on July 04, 2009
Off subject:

Since June 15th, we (New Orleans) have had the hottest stretch of days I can remember for anytime of summer & not just June. We have set numerous daily records and the hottest temperature recorded EVER at 104 recorded at Audubon Park. I don't think that is our "official" weather station, but I am interested in seeing how many records have been tied or surpassed since 6/15. I cannot seem to find that info....probably because the heat has made me stupid.

Thanks in advance if you know where I can find that info.
1157. IKE
2:58 PM GMT on July 04, 2009
94L....lol.

OMG, their really reaching for something.

Have a happy 4th everyone!
Member Since: June 9, 2005 Posts: 23 Comments: 37858
1156. KEEPEROFTHEGATE (Mod)
2:58 PM GMT on July 04, 2009
good morn i see we have naked STS 94L all i can say is

hahahahahahahahahahaha
Member Since: July 15, 2006 Posts: 171 Comments: 53827
1155. KEHCharleston
2:56 PM GMT on July 04, 2009
Quoting StormW:
95L

ABNT20 KNHC 041152
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT SAT JUL 4 2009

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

A NON-TROPICAL AREA OF LOW PRESSURE IS LOCATED IN STORMW'S BATHTUB. HOWEVER...GIVEN THE FACT THE BATHTUB IS DRAINING...CONDITIONS ARE UNFAVORABLE FOR DEVELOPMENT OF THIS SYSTEM.
ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE NEXT 48 HOURS.




Almost spit my coffee all over the monitor. Happy Independence Day!
Member Since: August 19, 2008 Posts: 6 Comments: 2490
1154. jrweatherman
2:55 PM GMT on July 04, 2009
94L is in the North Atlantic. Aren't water temps too cold for a pure tropical storm?
Member Since: May 17, 2009 Posts: 0 Comments: 943
1153. bappit
2:52 PM GMT on July 04, 2009
ummmmmmmm ... I just see healthy discussion.

Going to be another scorcher in SE Tx, but was hotter in BR yesterday. Was going to go over there but my car's not feeling well. Don't want to push it in the heat.
Member Since: May 18, 2006 Posts: 10 Comments: 6022
1152. nrtiwlnvragn
2:50 PM GMT on July 04, 2009
Quoting bappit:
That map of shear is based on computer models. There are no direct measurements made out there. By the way the convection moved east today, I'd say the shear is kicking 94L big time. If convection redevelops (I think some new convection will occur) it will be interesting to see if hangs around this time. My guess is it won't.


Partially true on the shear map, Atmospheric Shear

Background: Using the gridded atmospheric motion vector output u and v AMV components are averaged over an upper layer (150, 200, 250, 300, and 250 hPa) and a lower layer (700, 775, 850, and 925 hPa). The difference in these averaged components is used to compute the speed shear between the upper and lower layers. The contours show the vector magnitude shear (absolute value). The streamlines indicate the direction of the shear.

In the case when a tropical cyclone (TC) is present, the analyses are modified in the storm region by a procedure which removes the storm circulation within a prescribed radii. This allows a more representative depiction of the environmental shear acting on the storm.

Atmospheric Motion Vector (AMV) Gridded Analysis

Background: Analyses are calculated utilizing gridded output from the auto editing process of the satellite atmospheric motion vector (AMV) fields. The AMV data are fit to a one degree grid at the following heights (100, 150, 200, 250, 300, 350, 400, 500, 600, 700, 775, 850, and 925 hPa), with data sparse regions at each height filled with numerical model output. Grids consist of u and v wind components.

The background model used is usually the United States Navy's NOGAPS, but NOAA's GFS model serves as a back up.
Member Since: September 23, 2005 Posts: 14 Comments: 11161
1151. reedzone
2:45 PM GMT on July 04, 2009
94L is getting sheared, yes there is 10 knots over the storm, doesn't mean conditions are ripe lol. It's still getting sheared. 30% chance for Subtropical formation.
Member Since: July 1, 2008 Posts: 13 Comments: 7387
Come on guys its July 4th. Please don't argue.
Member Since: July 8, 2005 Posts: 259 Comments: 24018
Quoting hurricaneman123:


yea but its not dead yet


It will be soon. Have fun.
Member Since: Posts: Comments:
1148. bappit
That map of shear is based on computer models. There are no direct measurements made out there. By the way the convection moved east today, I'd say the shear is kicking 94L big time. If convection redevelops (I think some new convection will occur) it will be interesting to see if hangs around this time. My guess is it won't.
Member Since: May 18, 2006 Posts: 10 Comments: 6022
Quoting AllStar17:


That is an awful quick write-off to a storm. The shear is actually lessened over the storm, and it has been labeled 94L. It is heading for colder waters, but it has its window of opportunity to develop now.


No, it was an awful quick write off of a rotating puff of clouds with no future.
Member Since: August 16, 2007 Posts: 6 Comments: 12461

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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.