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.

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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)

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.

NOAA ups 2017 hurricane season forecast

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There’s now a 60 percent chance of an above normal hurricane season, NOAA said Wednesday. (Credit: NOAA)

NOAA issued its updated hurricane season forecast Wednesday, calling for up to 19 named storms, nine hurricanes and five major hurricanes. That’s up from a maximum 17 named storms forecast in May.

If disturbance 99L develops east the Bahamas as some forecasts suggest, and becomes Tropical Storm Gert, that would mean up to 12 storms could form before the season ends November 30. It would take us all the way up to Tropical Storm Tammy.

Franklin has been the only hurricane so far so that would leave as many as eight yet to come, based on the high-end of the new NOAA forecast. Franklin made landfall overnight in the State of Veracruz in Mexico as a Category 1.

An average season has 12 named storms.

“We’re now entering the peak of the season when the bulk of the storms usually form,” Gerry Bell, NOAA’s lead seasonal hurricane forecaster said. “The wind and air patterns in the area of the tropical Atlantic and Caribbean where many storms develop are very conducive to an above-normal season. This is in part because the chance of an El Niño forming, which tends to prevent storms from strengthening, has dropped significantly from May.”

Interestingly, Thursday’s early run of the GFS showed no tropical development in the Atlantic through at least August 26, a week before Labor Day weekend. The European (ECMWF) shows an all-clear through at least August 20, and the CMC is the only major model holding on to 99L — taking it harmlessly out to sea — with nothing of note after that over the next 10 days.

The Navy’s model, NAVGEM, dropoed 99L and the National Hurricane Center lowered chances of development for the system in its morning tropical weather outlook from 50 percent to 40 percent.

A low pressure system moving into South Florida from the Bahamas Thursday was forecast to dump heavy rain on the southern peninsula, but it looks to be a one-day event, according to the National Weather Service in Miami. And precipitation should drop off toward the north, with the bulk of it over South Florida and the Keys.

August has been a relatively dry month, so far, up and down the peninsula. Jacksonville is ahead on rainfall for the month, but most of the East Coast cities from Daytona Beach to Miami have rainfall deficits of up to 1.5 inches, and the Keys have built up a shortfall as well. Through Wednesday, Marathon had only recorded 0.02 of an inch of rain all month.

Most of the West Coast is short of normal rainfall as well, Tampa and Naples being exceptions.

RECORD WATCH: Miami booked a record warm low temperature Wednesday with 83, beating the previous mark of 82 set in 2009. Record warm lows were tied in Fort Lauderdale (83); and West Palm Beach (83).

Emily moves off-shore after soaking state; a look at July’s torrid Florida temps

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PM UPDATE: While Tropical Depression Emily continued to slide to the north well off the U.S. East Coast, the National Hurricane Center gave a low pressure system in the eastern Atlantic a 20 percent chance of developing into the next tropical cyclone by Saturday, and a new low in the Gulf of Mexico a 10 percent chance. The Gulf low was forecast to push toward Florida’s Big Bend area. (Credit: NOAA/ NHC)

EMILY RAINFALL: Sunday-Monday totals associated with the weekend cold front and tropical storm: Sarasota-Bradenton, 4.4; Punta Gorda, 3.22; Tampa, 3.05; Naples, 2.71; Fort Myers, 2.5; Jacksonville, 2.36; Gainesville, 1.92; Vero Beach, 1.84; Fort Pierce, 1.68; Fort Lauderdale, 1.67; Marathon, 1.32; Melbourne, 1.19; Orlando, 1.15; West Palm Beach, 1.04 inches; Miami, 0.99; Key West, 0.90; Daytona Beach, 0.81.

RECORDS SET: Monday’s rain and cloud cover kept temperatures down across the state, with many cities setting or tying records for coolest maximum temperature for the date. Fort Lauderdale’s high was 83, tying a record set in 1933; West Palm Beach was only 82, tying the mark from 1933; Naples reached 86, breaking the old record of 87 set in 1949; Orlando hit 78, breaking the old record of 80 set in 1965; Melbourne topped out at 83, busting the previous record of 84 set in 2001; and the high was 81 in Vero Beach, smashing the old record of 84 set in 1974.

Jacksonville tied a record low Monday with 69, matching the mark set in 2014.

JULY SLICED AND DICED: Temperatures were above normal from Jacksonville to Key West, although Miami failed to break its record streak for consecutive days at 90 or above thanks to Monday’s rain. Still, the city ended up with an average July high of 91.9 degrees and an average low of 79.6. Overall, that was 1.6 degrees above average.

Key West finished the month 1.1 degrees above normal while Marathon was 1.4 degrees on the plus side. West Palm Beach was also 1.6 degrees above normal and Naples checked in slightly above normal.

Jacksonville was a half-degree above average.

Other cities that came in on the plus side: Daytona Beach, 1.2; Melbourne, 2.6; Vero Beach, 1.6; Fort Pierce, 1.5; Tampa, 1.2; and Fort Myers, 0.6.

The two exceptions to July’s unusually torrid temps were Orlando, which was 0.4 of a degree below the July average; and Fort Lauderdale, which matched the 30-year average on the button with an overall temperature of 84.3 degrees.

It was also a wet month in Florida, with Miami posting 12.45 inches of rain, twice the July average. Naples had 11.24 inches, almost 4 inches above the July average. West Palm Beach’s 7.44 inches was 1.68 above normal. July precipitation was generally above average in Central, North and West-Central Florida as well.

Jacksonville finished July with 10.91 inches of rain, more than twice the normal amount.

AUGUST OUTLOOK: Florida’s above normal temperatures and rainfall should continue through August, NOAA’s Climate Prediction Center said Monday. The CPC’s 90-day forecast is for above average temperatures everywhere in the U.S., including Alaska, through the end of October.

 

Rare mid-summer front heads for Florida; East Coast continues to sizzle

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The cold front forecast to trigger a week-long rain event over most of the Florida peninsula should push into North Florida on Saturday, the National Weather Service said. Some strong storms and flooding are possible as the front sinks south, eventually stalling around the I-4 corridor. (Credit: NWS-Jacksonville)

Friday was one of the hottest days of the year up and down Florida’s East Coast — and the warmest so far in 2017 in West Palm Beach, where the temperature hit 94 with a heat index of 107.

The temperature topped out at a blistering 97 in Vero Beach, 95 in Fort Pierce and 96 in Melbourne, where the city added an incredible fourth consecutive day of record warm lows with 79, breaking the old record of 78 set in 2011. Record warm lows were also set or tied in Melbourne on Tuesday, Wednesday, and Thursday.

In West Palm Beach, it was also the hottest day since last August 6, when a high of 94 ended a three-day string of highs of 94 and 95.

Friday’s high was 93 in Miami, 92 in Fort Lauderdale, and 90 in Naples, which tied a record warm low with 79 — matching the mark set just two years ago in 2015.

It was 94 in Jacksonville and Orlando.

Even in the normally milder Keys, the high was 94 in Marathon and 90 in Key West, where Friday’s low of 84 tied the record for warmest low for the date.

It was mostly in the low 90s on the West Coast, with Tampa hitting 93.

Friday’s rainfall totals around the state were light — a very spotty inch or two fell in inland locations from Miami up to Vero Beach — but it was likely the calm before the storm. Five-to-six inches rain are forecast for Central and North Florida over the next week as a frontal boundary stalls over the I-4 corridor, NOAA’s Weather Prediction Center says.

The rare July cold front is in connection with the strong low pressure system over the Mid-Atlantic States, which was hammered by storms on Friday. Parts of Montgomery County in southern Maryland reported more than 6 inches, the Community Collaborative Rain, Hail & Snow Network reported.

South Florida looks to be in line for at least 2-3 inches next week, and showers developing over the peninsula this weekend will likely dump some needed rain along the East Coast.

TROPICS WATCH: A new tropical wave southwest of the Cabo Verde Islands earned a yellow X on the Saturday morning National Hurricane Center forecast map. It had a 20 percent chance of development by Thursday, forecasters said. The disturbance, which was packing a modest amount of convection, is part of a robust train of waves rolling over tropical areas of Africa toward the Atlantic coast.

Forecast models were all over the place in their Saturday runs, with the GFS showing long-range development in the Gulf of Mexico, the European (ECMWF) off the southeastern U.S. coast, and the Canadian (CMC) predicting a vigorous storm east of the Bahamas in seven to 10 days.

When and where Tropical Storm Emily will pop up is anybody’s guess. But signs are pointing to an active August and September that could bring a few nail-biters to Florida and other parts of the Atlantic Coast.

Drier weather in Florida’s weekend forecast; tropics take a break

Thursday’s wet conditions kept South Florida July precipitation engine running on all cylinders, cylinders, and put a lid on temperatures with plenty of cloud cover.

It was the first day of the month in West Palm Beach that the high  temperature failed to reach 90 degrees, and another 0.29 of an inch was collected in the rain bucket at Palm Beach International Airport.

Miami reported 0.06 of an inch while 0.23 of an inch fell in Fort Lauderdale. Naples reported a tenth of an inch.

It was drier in the Keys, though, with Marathon hitting a high of 92. And Key West tied a 28-year-old record warm low temperature record with 84 degrees.

East-Central coastal locations were also generally dry, but Orlando was slammed with another 1.64 inches of rain on Thursday, bringing the city’s July total to an impressive 8.53 inches — 3.91 inches over normal for this point in the month.

Record rainfall was reported in Orlando on Monday.

Drier weather was forecast to move into the peninsula for the weekend.

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Slow-moving storms soaked Central Florida earlier this week, with Orlando reporting a record 3.09 inches on Monday. (Credit: NWS-Melbourne)

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TROPICS WATCH: The Atlantic remained quiet on Friday, and the National Hurricane Center was predicting no tropical development at least through the middle of next week. None of the major forecast models show anything of consequence spinning up over the next seven to 10 days.

The Atlantic continues to be dominated by dry air, which helped destroy Tropical Storm Don and wiped 96L off the NHC forecast map earlier this week.

But conditions are expected to become more favorable for tropical development when August starts, and the tropical wave train from the coast of Africa is still in full swing. An active August and September seems likely.

Colorado State University will have another updated 2017 seasonal forecast on August 4, and hurricane expert Philip Klotzbach will begin issuing outlooks every two weeks in August and September.

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Another tropical wave was getting ready to roll off the coast of Africa on Friday. (Credit: NOAA)