Florida forecasters raise flooding concerns over approaching tropical weather

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CHANCES DIMINISHING: Odds for development of disturbance 92L were cut back from 70 percent to 60 percent by the National Hurricane Center at 2 p.m. Forecasters said it continued to show signs of organization, but was about to run into high wind shear. (Credit: NHC)

ORIGINAL POST: Florida’s rainy weekend could stretch into a wet week with potential flooding if the tropical disturbance nearing the Lesser Antilles delivers a second precipitation punch to the area on Wednesday or Thursday.

The system, being tracked by the National Hurricane Center as Invest 92L, could be on Florida’s doorstep as early as Wednesday morning. But luckily, conditions are not forecast to be favorable for development, and the major forecast models such as the GFS and European (ECMWF) are not impressed.

Still, after a potential soaking from a tropical wave due to pass over the Florida peninsula Saturday and Sunday, another round of moisture mid-week could trigger flooding issues, the National Weather Service in Miami said.

The system was 750 miles east-northeast of the Leeward Islands Friday morning and was “continuing to show signs of organization,” NHC forecasters said. “While it would take only a slight increase in organization for a tropical depression to form later today or tonight, upper-level winds are becoming less favorable for development.”

Once the low gets west of Puerto Rico, wind shear could jump — on Friday the shear was running 30-40 knots.

Still, sea surface temperatures are running about a degree above normal north of the Greater Antilles and around the Bahamas, and warm water is fuel for tropical systems. If it does strengthen, however, the low could be pulled north off the coast of Florida.

National Weather Service forecasters said Friday morning: “The exact details of the weather Tuesday through Thursday will hinge on the exact development and movement of the tropical disturbance currently located about 1000 miles east of the Leeward Islands. As of 2 a.m., NHC currently gives this feature a 70 percent change of developing into a tropical cyclone in 2 days and 5 days respectively. It is expected that this feature will continuing moving northwest and potentially be in the Bahamas and South Florida as we head into mid-next week.

“Regardless of development, at this point signs are pointing towards another period of heavy rainfall across the region for at least Tuesday and Wednesday. Which, especially depending on this weekend`s rainfall, may raise flooding concerns across the area.

“All residents and visitors or South Florida need to continue to monitor this tropical disturbance through the weekend.”

NOAA’s Weather Prediction Center was showing more than 4 inches of rain falling along the southeast Florida coast through the end of next week.

Disturbance 92L, of course, wasn’t the only player in the Atlantic Basin Friday. Tropical Storm Harvey was battering the Windward Islands, and a second tropical wave in the eastern Atlantic was given a 40 percent chance of development by the NHC over the next five days.

Harvey was forecast to top out as a 70-mph tropical storm on Monday before it rams into Central America. People in the Windward Islands posting on the Caribbean Hurricane Network reported heavy rain and some power outages on Barbados.

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Above: Friday’s Caribbean satellite water vapor image showed Tropical Storm Harvey pounding the Windward Islands while tropical disturbance 92L to its northeast was moving into an area of higher wind shear. Below: forecast tracks for 92L. (Credit: NOAA/ NHC/ SFWMD)

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Soggy weekend forecast for Florida as tropical wave rolls in

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TROPICAL STORM HARVEY: The National Hurricane Center began issuing advisories on the ninth named storm of the season at 5 p.m. Forecasters predicted the system — tracked over the last several days as Invest 91L — would near-hurricane status on Monday as it nears the coast of Honduras. A Tuesday morning landfall in Belize was in the initial forecast.

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Puerto Rico was getting hammered Thursday by a tropical wave and upper-level low, center, while Invest 91L (right) and 92L (far right) continue west. (Credit: NOAA)

A potent tropical wave that has been dumping moderate to heavy rain over Puerto Rico is set to dampen the Florida peninsula this weekend.

San Juan picked up 1.76 inches of rain Thursday morning and the Roosevelt Roads Naval Station reported 2.06 inches.

All of that moisture was moving west-northwest toward Florida and should arrive in time to drive rain chances up to at least 50 percent over parts of Florida on Saturday and Sunday as it heads west.

The rain is associated with an upper-level low and is out ahead of the two tropical features under scrutiny by the National Hurricane Center — Invests 91L and 92L. In the satellite image above, the aforementioned wave is shown near Puerto Rico and moving into Hispaniola on its way to the Bahamas.

Disturbance 91L is east of Barbados and 92L was still at around 43W.

NOAA’s Weather Prediction Center is forecasting around an inch of rain for parts of the Florida peninsula through next Tuesday, with 2 inches or more forecast for the interior from the Everglades all the way north through Orlando the Gainesville area.

Heavier rains may roll through toward the middle of next week if Invest 92L ends up moving in the direction of South Florida or the Keys, which has been the favored path of foreast models over the past few days. Luckily, there are indications that 92L may not have much chance to power up into a depression or tropical storm due to high wind shear north of the Greater Antilles.

Shear doesn’t really drop off until you get into the Gulf of Mexico.

As of Thursday, the WPC Was indicating more than 3 inches of rain over the next seven days for parts of the Middle and Upper Keys.

Rain chances bounce back into the 50 percent range again on Tuesday and Wednesday after one drier day — luckily on Monday, the day of the eclipse.

Atlantic tropical waves

Disturbance 91L went code red on Thursday, indicating a high chance of development. The other two areas of interest in the Atlantic have a medium chance of tropical development. (Credit: NWS-Key West/ NHC)

Forecast models are fairly unanimous in bringing 91L through the Caribbean and west all the way to Central America or Mexico. Forecasters at the NHC increased development chances of 91L to 70 percent on Thursday, and an Air Force reconnaissance plane was scheduled to investigate it Thursday afternoon as it bears down on the Lesser Antilles.

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Forecast tracks for Invest 92L. (Credit: SFWMD)

HURRICANE ANNIVERSARY: A tropical storm quickly blew up into a hurricane 50 miles south of Key West 131 years ago. The unnamed storm was moving west through the Florida Straits on August 17, 1886, when it rapidly intensified. “A man was killed when a building collapsed on Duval Street,” Forecasters at the National Weather Service’s Key West office said Thursday. (Credit: NWS-Key West)

Forecasters track tropical trio as Gert nears Category 2 strength

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Two systems in the Tropical Atlantic have a 50 percent chance each of development by Monday, according to the National Hurricane Center. The disturbance off the coast of Africa has a 40 percent chance. (Credit: NHC)

There’s a meteorological traffic jam going on in the Tropical Atlantic, with three strong waves rolling toward the Lesser Antilles all with a chance to become the next named storm.

And that’s in addition to Hurricane Gert, spinning well off the Mid-Atlantic Coast. The storm was still strengthening Wednesday and forecasters predicted it would become the season’s first Category 2 hurricane with winds of 100 mph. UPDATE: Gert became the first Category 2 with winds of 100 mph at 5 p.m., but NHC forecasters said: “The window of opportunity for additional strengthening appears to be closing.”

The three systems are led by Invest 91L, which is apparently bound for the Caribbean; 92L, which could skirt the northeastern Lesser Antilles and move in the general direction of the Bahamas; and the potential 93L, which just emerged from the coast of Africa.

All three were given a 40 percent chance of becoming tropical depressions or storms over the next five days by the National Hurricane Center. If they all developed, we’d have Harvey, Irma and Jose.

It’s too early to say where these systems will end up, but 91L looks like it could continue to sweep west and impact Central America. The next one, 92L, has some trouble-making potential for the U.S. Coast, based on mid-week forecast models. And 93L is a wild card.

This is the most dangerous time of the year for tropical weather, and the disturbances will be getting very close scrutiny from the NHC.

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South Florida eclipse

South Florida’s view of the eclipse. (Credit: NWS-Miami)

AND SPEAKING OF TRAFFIC JAMS: It’s the Super Bowl of astronomical events, so expect this weekend’s coverage of the “Great American Eclipse” to at least equal, or even surpass, the breathlessly hyped NFL football extravaganza.

But Monday’s solar eclipse viewing will be generally poor throughout the Florida peninsula due to cloud cover, forecasters at AccuWeather predict.

The closest place to the peninsula where the total eclipse can be viewed is Charleston, SC where there’s a 40 percent chance of rain, according to Weather Underground — and a 100 percent chance of traffic gridlock as people jam into the eclipse path.

Charleston is 522 miles from West Palm Beach, which would ordinarily be a seven-hour drive. But if you plan on getting up early Monday morning and driving up to see the Big Event, good luck.

There are 200 million Americans living within 500 miles of the eclipse, Forbes reports, about two-thirds of the U.S. population. “Previous eclipses have seen two-hour commutes turn into twelve-hour slogs, and this eclipse is poised to outdo them all,” the magazine said in June, predicting “the worst traffic jam in American history.”

Absent cloud cover, people in the Jacksonville area would see 85-95 percent of the sun obscured around 2:45 p.m.

West Palm Beach would get an 82 percent view, 78 percent in Miami and 75 percent in Flamingo.

RECORD WATCH: The low in Naples Tuesday was 80, which tied a record warm low for the date set in 2010.

 

Four tropical systems dominate busy Atlantic

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NHC forecasters are watching four systems in the Atlantic, including Hurricane Gert. (Credit: NHC)

Much of the tropical Atlantic’s Main Development Region was ablaze in color Tuesday as the National Hurricane Center monitored Hurricane Gert along with three potential tropical disturbances.

The MDR, which stretches from the coast of Africa through the Caribbean to coastal Central America, was host to 91L, apparently bound for the Caribbean; a wave west-southwest of the Cabo Verde Islands, and another system due to emerge off the African coast Wednesday.

The two- and five-day Tropical Weather Outlook uses yellow to denote a low chance of development (0-30 percent); orange a medium chance (40-60 percent); and red for a high chance (70 percent or higher).

Chances of development for Invest 91L were actually knocked back Tuesday morning by NHC forecasters, who said conditions would become more hostile for tropical storm development once it makes it into the Caribbean. The eastern Caribbean is often considered a graveyard for long-tracking Atlantic systems due to dry air coming off South America and higher wind shear.

If a storm can hold any kind of structure into the Central Caribbean conditions usually improve dramatically in the West.

Forecast models have been flip-flopping on 91L, and a southerly route was favored on Tuesday. Most of the members of the GFS Ensemble predict the storm will continue to push west all the way to Mexico’s Yucatan Peninsula, as last week’s Hurricane Franklin did.

As for Hurricane Gert, the second of the season, forecasters predicted it would top out as an 85-mph storm on Wednesday before losing its punch and becoming post-tropical on Friday. No land areas should be affected.

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Forecast tracks for Invest 91L. (Credit: SFWMD)

FLORIDA FORECAST: A tropical wave due to arrive over the weekend pushes up precipitation chances in South Florida to 50 percent, according to the National Weather Service. Rain chances also climb into the 50 percent range in West- and East-Central Florida, but remain lower in the Keys and in North Florida, at around 30 percent.

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Rain chances increase this weekend, but there will be no relief from the heat, forecasters said. (Credit: NWS-Miami)

Hottest day of the year in West Palm; Tropical Storm Gert forms in Atlantic

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UPDATE: Tropical Depression Eight became Tropical Storm Gert at 5 p.m., and forecasters at the National Hurricane Center predicted it would top out as a 65-mph storm by Tuesday as it moves toward the north and northeast. It was not expected to affect land. (Credit: NHC)

Saturday’s high temperature in West Palm Beach tied July 28 and 29 as the hottest day of the year — a sizzling 94 degrees between 2-4 p.m. The heat index climbed to 107.

Miami’s heat index topped out at 105 with a high temperature of 93, Fort Lauderdale hit 90 with a heat index of 102; and in Naples’ the high was 90 but the heat index failed to break into triple digits with 99.

Highs were in the low 90s in Central Florida; Stuart also recorded a heat index of 107.

More peak summer heat was forecast for the Florida peninsula over the next couple of days as “dry air pockets” from the Bahamas, National Weather Service forecasters in Miami said in their Sunday analysis. Look for more record warm lows on the East Coast next week, they said.

TROPICS WATCH: Conditions tend to change overnight in the tropics — particularly when you’re heading into the peak of the hurricane season.

To wit: Tropical Depression Eight formed late Saturday, and appeared close to tropical storm strength. But the cyclone, which would get the name Gert, was following model forecasts and was tracking north-northwest, which should be followed by a turn toward the north-northeast on Monday.

The storm is expected to make a wide right turn around Bermuda, so no land will be affected if the forecast holds.

But another strong wave tumbled off the coast of Africa Saturday and the National Hurricane Center immediately tagged it Invest 91L. Ten-day forecasts are to be taken with a grain of salt — pre-Tropical Storm Gert was originally forecast to cause problems in the Florida Keys — but 91L has clear model support.

Sunday runs of the GFS showed the storm over the Bahamas, then making a turn toward the north and making landfall in South Carolina toward the end of next week. The European (ECMWF) has the storm crawling up the northern coast of Cuba on Wednesday, August 23 heading in the general direction of the Keys.

 

Better beach weather arrives as tropical disturbance heads out to sea

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Invest 99L appeared to be bearing down on the Bahamas Saturday, but forecasters were predicting a sharp-right turn into the open Atlantic. (Credit: NOAA)

Disturbance 99L looked to be finally getting its act together after a  leisurely 10-day cruise across the Atlantic Ocean. There’s a good chance it will become the season’s seventh named storm, Gert, forecasters said Saturday.

But if it does in fact spin up — the National Hurricane Center is giving it a 60-70 percent chance over the next two to five days — it is likely to be merely a season statistic rather than a storm that makes Big News. Forecast models are fairly unanimous in taking the system northwest, north and then northeast out to sea, splitting the uprights between Bermuda and the U.S. East Coast.

After that, models show another long-tracking system popping up in the eastern Atlantic toward the end of next week, and perhaps getting some traction as it nears the Lesser Antilles the week of August 21.

The GFS predicts — for now, at least — that this system will follow the path of 99L and curve out to sea well east of the U.S. coast. We’ll keep fingers crossed, since by that time we’ll be nearing Labor Day weekend, when historically some of the most infamous hurricanes have occurred.

The next name on the Atlantic list after Gert is Harvey.

How does this season compare so far? Last year around this time we were about to deal with Major Hurricane Gaston (August 22) , which did not affect land; and Hurricane Hermine, which made landfall in the Florida Panhandle on September 2 as a Category 1.

The only other storms to impact Florida last year were Tropical Storm Julia, which in mid-September achieved the rare distinction of spinning up over land near Jacksonville after running up Florida’s East Coast as a depression; and early October’s way-too-close-for-comfort Hurricane Matthew.

This year the NHC is using the same name list as 2005, the busiest season on record. That year, Franklin formed July 21; Gert formed July 23 and Harvey formed on August 2.

RECORD WATCH: Daytona Beach and Orlando tied record warm lows Friday with 78 and 77, respectively.

Beach weather

SUNSCREEN REQUIRED: After a wet week, better beach weather arrives for the weekend, but forecasters say a few storms are still possible. (Credit: NWS-Miami)

Bahamas low socks Fort Lauderdale with record rainfall

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The National Weather Service in Miami posted this record rainfall note for Fort Lauderdale Thursday morning. More rain fell later for a daily total of 3.43 inches.  (Credit: NWS-Miami)

A low pressure system swept into Florida from the Bahamas on Thursday, delivering record rainfall to Fort Lauderdale and impressive totals up and down the East Coast.

Fort Lauderdale-Hollywood International Airport measured 3.43 inches, beating the old precipitation maximum for the date of 3.35 inches set in 2003. Most of the rain fell between 8-10 a.m.

With all the rain and cloud cover, Fort Lauderdale’s high was only 85 on Thursday, a record cool high temperature record for the date. The previous record was 86 set in 2012.

Miami reported 0.94 of an inch and 1.34 inches fell in West Palm Beach, while Naples reported just 0.02 of an inch. An observer in Boca Raton reported 2.76 inches.

In East-Central Florida, Melbourne had 0.13 of an inch; Vero Beach reported 0.95 of an inch. Just 0.05 of an inch fell in Fort Pierce, but more than 2 inches soaked parts of southeastern St. Lucie County.

Up to half an inch fell in parts of Collier, Lee and Charlotte counties on the Southwest Coast, while in the Keys just a trace was recorded at Marathon and Key West picked up 0.03 of an inch.

More rain — possibly heavy — could fall Friday as the low moves slowly north along the Atlantic Coast, forecasters said. The National Hurricane Center was still giving the area a 10 percent chance of developing into a tropical system, although forecasters said upper-level winds weren’t favorable.

Meanwhile, tropical disturbance 99L — which has been ambling across the Atlantic for more than a week now — was given a 30 percent chance of development by Sunday and a 50 percent chance by mid-week. Either way, it looks like it will be an out-to-sea storm and no problem for the U.S. East Coast.

The NHC doesn’t have anything else brewing in the Atlantic, and forecast models show a fairly quiet week to 10 days.

As of Friday, we are four weeks away from the statistical peak of the hurricane season, which is September 10.