Heavy rain possible in South Florida next week; Jeff Masters leaving Weather Underground

Expected rainfall totals SFL

Expected rainfall totals through Tuesday in South Florida. (Image credit: NWS-Miami)

RAIN EVENT UPDATE: The National Weather Service has been talking over the past few days about an increase in precipitation across the peninsula the middle of next week. Forecasters say this event is coming into better focus, due to a trough coming down from the north and another coming up from the south.

“This trough will slowly move east across the Florida Peninsula middle of next week,” the NWS Miami office said Saturday. “At the same time, a low level trough over the Northwestern Caribbean Sea will move slowly northward into South Florida. The combination of these will bring in deeper tropical moisture to South Florida leading to scattered to numerous showers and some thunderstorms.”

Rain chances around South Florida jump from 50 percent Monday to 70 percent Tuesday and 80 percent on Wednesday.

“We will need to continue to monitor the latest forecast models on this developing trend of possible heavy rainfall over South Florida for early to middle of next week,” forecasters said.

Rain chances in Central Florida are at 30-40 percent during this period; but up to 60 percent in the Tampa area and 40-50 percent in North Florida.


SUDDEN TRACK CHANGE: Jeff Masters, who co-founded Weather Underground in 1995 and developed a popular tropical weather blog — most recently called Category 6 — is leaving the IBM-owned company at the end of the month.

Weather Underground was sold to The Weather Channel in 2012, and to IBM in 2016.

“I am grateful to weather.com and IBM for making me feel welcome and allowing me to continue covering what I love, but I’ve never felt comfortable in a large corporate environment–I was more in my element back in the old days of WU,” he said in a Category 6 blog post Friday.

Masters will be writing for the Scientific American website with a new blog called “Eye of the Storm: the Science Behind Extreme Weather.”

“I will be averaging 50 posts per year—a lot less than the 150 – 200 posts per year I’ve been doing for Category 6.”

His co-blogger, Bob Henson, will continue writing for Category 6.

“The Scientific American website does not allow comments on their posts, so I plan on engaging with the WU community in the comments section of Category 6 to discuss my posts at Scientific American,” Masters said.


Continental US - Clean Longwave Window - IR

Saturday’s Gulf of Mexico satellite showed the disturbance in the western Caribbean. (Image credit: NOAA)

TROPICS WATCH: The National Hurricane Center predicts an area of low pressure will form over the next five days in the Atlantic between the Azores and Bermuda. They gave it a 40 percent chance of becoming the next tropical depression, or Tropical Storm Melissa, as it moves toward the west.

An area of disturbed weather in the northwestern Caribbean (left) was not on the NHC’s radar, but it’s been firing up some fairly vigorous convection over the last couple of days.

The GFS is showing a couple of systems toward the end of its 16-day run in the southern Caribbean, one of which rolls into Central America and another that comes off the Central America Central America coast late in the run, and moves into the Keys and South Florida as a tropical storm.

The forecast model has been flip-flopping back and forth on development in the Caribbean for at least the last week, but there doesn’t seem to be anything of concern in Florida’s neck of the woods over the next week to 10 days or so.


Sticker shock on tab to protect Florida cities from sea level rise

The cost of protecting U.S. cities vulnerable to the effects of sea level rise will jump to $42 billion by 2040, The New York Times said in an article published Wednesday.

That’s for all cities with populations greater than 25,000 — expanding the list to smaller cities would hike the cost to $400 billion, the newspaper said, citing studies by the Center for Climate Integrity.

Climate change will cost Florida more than any other state, the Tampa Bay Times said in a followup article. “It’s not even close.”

Richard Wiles, the organization’s executive director, told The New York Times: “Once you get into it, you realize we’re just not going to protect a lot of these places. This is the next wave of climate denial — denying the costs that we’re all facing.”

The Center for Climate Integrity wants oil and gas companies to help pay for the cost of adapting cities to sea level rise.

The most expensive city to protect will be Jacksonville, Florida, according to the group, at $3.5 billion. Also in the top 10 are Tampa, at number six: $938.4 million; and St. Petersburg, at number nine: $751.4 million.

New York City comes in at number two and — somewhat surprisingly — New Orleans is down at number 10.


Keys heat index

Saturday heat index.png

CFL heat index

(Image credits: NWS-Key West, top; NWS-Miami, middle; NWS-Melbourne, bottom)

TRIPLE DIGIT REDUX: There was no escaping the heat around the Florida peninsula on Friday.

Maximum heat index readings in South Florida: Kendall-Tamiami Executive Airport, and Homstead Air Reserve Base, 107; Naples, 106; Miami, Fort Lauderdale, and West Palm Beach, 105;

Keys: Marathon, 106; Boca Chica Naval Air Station, 103; and Key West, 100.

East-Central Florida: Daytona Beach, 108; Melbourne and Titusville, 106; Vero Beach and Kissimmee, 103; and Orlando, 102.

West Coast: Fort Myers-Southwest Florida International Airport, 104; Brooksville, 103; Sarasota and Winter Haven, 102; Tampa, 101.

North Florida: Cross City, 108; Ocala, 106; and Gainesville, 103. The actual high in Jacksonville — not the heat index — was 97, with a dew point of 79. The dew point was a record for the date.

Another heat advisory was issued by the National Weather Service for inland Collier County and Mainland Monroe County for Saturday from 10 a.m. to 7 p.m.

After more heat Saturday and Sunday, temperatures should begin to moderate on Monday, thanks to more cloud cover and easterly winds, forecasters said.

South Florida, West Coast slammed with close to 5 inches of rain


Look for more hefty rainfall totals on the East-Central Coast into Thursday, before more sunshine — and heat — returns. (Image credit: NWS-Melbourne)

Monday was another soggy weather day in South Florida — and drivers and pedestrians found themselves sloshing around the West-Central Coast, too.

An official 1.89 inches was reported at Fort Lauderdale-Hollywood International Airport, putting the city almost 5 inches over normal for June rainfall. Cloud cover kept high temperatures down, and Naples tied a record cool maximum with 81 degrees.

It was the coolest high temperature in Naples on June 17 since 1982.

Miami officially checked in with 0.61 of an inch, while West Palm Beach racked up 0.75 of an inch.

There were numerous reports of 2 inches or more to CoCoRaHS, and an observer just north of LaBelle found 4.90 inches in his backyard bucket.

Another observer near Bowling Green in Hardee County picked up 3.50 inches. And north of Tampa, an observer near Wesley Chapel reported 3.45 inches. And a CoCoRaHS participant in Spring Hill, Hernando County, reported 3.78 inches.

The Keys have finally been getting into the act as well. Marathon had 1.34 inches on Monday, while 0.45 fell in Key West.

More heavy rain was in the forecast for Tuesday and Wednesday, but things are expected to dry out Thursday and Friday, when the sun comes out just in time for the summer solstice, driving heat index readings up into the triple digit range in South and Central Florida, according to forecasters.


The entire southeastern U.S., from Florida to Texas and as far north as Missouri, will likely see heat index readings of at least 100 degrees on Friday, the first day of summer. (Image credit: NOAA/ WPC)


Weather reports

CITIZEN WEATHER REPORTS: You got ’em, the National Weather Service in Miami wants ’em. Doesn’t matter whether you are a trained storm spotter or Mr. General Public. Call, or post to Twitter or Facebook. (Image credit: NWS-Miami)

Another round of brutal heat set to arrive with summer solstice


The summer solstice occurs Friday at 11:54 a.m. Heat index readings are expected to soar by the end of the week in places like Texas and South Florida. (Image credit: NOAA/ WPC)

Temperatures were a little more subdued around Florida on Saturday, thanks to cloud cover and sea breezes. Most locations turned in highs in the 80s — Pembroke Pines in Broward County reported a high of 81 to the National Weather Service.

Tampa was 87, and it was 89 in both Miami, Fort Lauderdale, and West Palm Beach — only the second day this month that the high failed to reach 90 in Miami.

Rain chances finally begin to diminish late in the week, and the National Weather Service in Miami said in its Sunday forecast discussion: “The return of above normal temperatures and triple digit heat indices are also possible across the region by the end of the (forecast) period.”


RAINFALL REPORT: CoCoRaHS observers near LaBelle in Hendry County reported up to 2.70 inches of rain on Saturday, while an observer east of Lake Placid in Highlands County measured 1.74 inches.

Most of the heavy rain was on or near the West Coast, but an observer in Miami reported 1.80 inches.

Parts of Sarasota County checked in with up to 2 inches, and 2.4 inches were reported in northern Pinellas County.


TROPICS WATCH: Global forecast models continue to show nothing of significance forming in the Atlantic in the next 10 days, and there’s nothing of interest on the National Hurricane Center Tropical Weather Outlook map through at least Friday. The newly minted version of the GFS shows a system trying to spin up in the northwestern Caribbean off the coast of Belize the last week of June, but fizzling out over the Yucatan Peninsula.

Experts are continuing to weigh in on how the new GFS, which launched last week, will handle tropical storm forecasts. Weather Underground blogger Bob Henson had an interesting post on the subject on Friday, emphasizing NOAA’s prediction that the FV3, the new and improved version of the GFS, will not only be better at track forecasting but also intensity forecasts. The latter has been the most difficult for the NHC to show improvement in, as forecasters themselves will readily admit.

“Once concern,” Henson says, is that apparently the old GFS did better on track accuracy after day six, and that the FV3 did better on forecasting the track for weaker storms. “FV3’s performance on hurricanes versus tropical storms and tropical depressions will bear watching in 2019 and beyond,” he said.

On the other hand, the new model may be better at predicting central pressure of storms that do form, and that could reduce the number of false alarms that the old GFS consistently had during hurricane season.

Henson writes: “The new FV3 makes some big strides toward reducing the number of ‘boguscanes’, according to NOAA/EMC physical scientist Fanglin Yang. The center’s evaluation found that the FV3 reduces the false-alarm rate for tropical cyclogenesis by 48 percent in the Atlantic and 33 percent in the East Pacific, as compared to the previous GFS.”

The jury is out, but we’ll know more in the next month or two as the heart of the season begins to unfold.

North Florida drought conditions recede; new GFS gets high marks

Panhandle cold front

WARM, BUT DRY: The cold front that’s expected to make its way down the Florida peninsula, and stall out in Central Florida, was just moving into the Florida panhandle on Thursday morning. Not much cooler weather is expected after the cold front moves through, but drier air will arrive in areas to the north of the front. In Dothan, Alabama northwest of Tallahassee, humidity levels are forecast by Weather Underground to be as low as 30 percent on Thursday. But National Weather Service forecasters in Tallahassee added: “Even though it’s a cold front… highs will actually be warmer tomorrow than the last few days!” (Image credit: NWS-Tallahassee)


DWINDLING DROUGHT: Drought conditions in Florida receded slightly this week and are now confined mostly to the northern tier of counties, from Nassau County in the northeast west into the Central Panhandle. Several counties in the Big Bend area swapped Moderate Drought for Abnormally Dry conditions, according to the U.S. Drought Monitor.

There were actually few areas of drought in the U.S. this week. Outside of North Florida and coastal areas of Georgia up through North Carolina, the only areas on Thursday’s map were in extreme northern North Dakota; western New Mexico; and parts of Washington and the Northwest.

California is clear of drought, although the southwestern corner near San Diego is Abnormally Dry.


‘MODEL-CANES’ ON THE WAY OUT? NOAA officials have high hopes for the new and improved GFS forecasting model they began using Wednesday, the Finite-Volume Cubed-Sphere, or FV3. Will their confidence be justified?

Truth be told, the European model (ECMWF) always had a little more respect than the GFS in some forecasting circles — although the GFS performed well on occasion — but NOAA officials are hoping the upgrade changes all of that.

“The significant enhancements to the GFS, along with creating NOAA’s new Earth Prediction Innovation Center, are positioning the U.S. to reclaim international leadership in the global earth-system modeling community,” Neil Jacobs, acting NOAA administrator, said in an agency news release posted after a morning press conference.

An important question for people in Florida, Texas and the southeast coast is how the new model will fare during hurricane season. That wasn’t specifically addressed in the NOAA news release, but Matt Gray, a meteorologist for NBC2 based in Fort Myers, posted a blog on the topic Wednesday night.

“How will the new FV3 GFS do when the next hurricane comes? NOAA has tested it using data from storms over the past few seasons, so we have a pretty good idea,” he said.

The new FV3 will be better than the old GFS at forecasting intensity, he said. The old model tended to over-sell intensity, or keep storms stronger longer.

“The new GFS did a lot better with how intense Hurricane Florence was when it made landfall in North Carolina last year,” Gray said. “It’s just one of many examples where the new model did a lot better with storm strength.”

An attendant advantage to the new model is that since it’s better at forecasting strength, the FV3 may be better at avoiding what some weather watchers call “ghost storms,” or what Gray calls “model-canes.” These are tropical storms or hurricanes that pop up on model runs more than 10 days in advance, with no support from other models. The next day they may be dropped.

“Since the new GFS looks like it will be better at not strengthening tropical systems too much, that may also keep these ‘fake storms’ from showing up at all.”

Track accuracy looks about the same as the old GFS, Gray said.

Hot times in Sarasota; rainfall reports needed in the Keys

CoCoRaHS Keys

KEYS COURTS COCORAHS OBSERVERS: The National Weather Service in Key West noted Wednesday that the citizen observation network turns 21 years old this month. It started in June, 1998 in Fort Collins, Colorado. You can find rainfall observations pretty much anywhere in the country, but they are scarce in the Florida Keys and Monroe County. The NWS Key West is soliciting people to sign up. “We could use your observations!” the office said Wednesday in a Facebook post. You can do so at http://www.cocorahs.org. (Image credit: NWS-Key West)

Tuesday Florida rainfall reports from CoCoRaHS: Orange County, south of Winter Garden, 2.5 inches; western Jefferson County near Waukeena, 2.28 inches; Suwanee County near Live Oak, 2 inches; northeastern Nassau County, 1.70 inches; and western Putnam County, 1.67 inches.

Parts of Hillsborough County picked up around a half-inch, while totals were light in South Florida, except an observer west of Boynton Beach in Palm Beach County reported 0.78 of an inch.


WHAT KIND OF FRONT WAS THAT? The National Weather Service in Miami said upper level troughing over the southeastern U.S., “along with its corresponding surface low, will depart toward the northeast through the latter portion of the week. In the wake of this departure, an attendant cold front will begin sliding down the Florida peninsula before stalling across Central Florida.”

This time of the year, a front is a cold front pretty much in name only. Thursday night’s forecast low in Gainesville, for example, is 69 … but Friday’s forecast high is 90. Thursday night’s low in Lake City, meanwhile, is expected to tumble all the way down to 66 degrees. Come to think of it, that sounds pretty nice.


TROPICS WATCH: Wednesday morning’s run of the GFS shows a storm developing in the Caribbean June 28 and moving toward Belize or the Yucatan Peninsula. The GFS FV3, which becomes operational for NOAA this week, does not concur. The European model (ECMWF) is clear for the next 10 days and even the Canadian forecasting model (CMC) shows clear sailing through June 22.

The National Hurricane Center says no storm formation is expected through at least Monday.


RECORD REPORT: Marathon had the state’s high temperature in Tuesday’s National Weather Service roundup with 96 — and yes, that was another record high for the date. Marathon’s low of 84 was also a record warm low.

The low in Sarasota was 80, which busted the old record warm low for June 11 of 79 set in 2007.

With fanfare, NOAA officially unveils new forecast model Wednesday

It’s here! It’s here! NOAA is launching its new-and-improved forecasting system on Wednesday, the GFS FV3, which replaces the old GFS model that has been around, in one form or another for almost 40 years.

Neil Jacobs, acting NOAA Administrator, will host a press conference at 11 a.m. EDT to talk about the transition to the new model. The old GFS will continue running until September 30, according to The Washington Post.

Actually, the FV3 has been running since last year but the GFS has continued to be the main source of everything from precipitation forecasts to temperature forecasts by the National Weather Service.

NOAA boasts that the FV3 — abbreviated for Finite Volume Cubed-Sphere dynamical core — will bring “unprecedented accuracy” to NWS forecasts. And it works faster with today’s high speed “supercomputers.”

It’s able to “zoom down to local scales and provide images of up-down air fluctuations, allowing us to resolve thunderstorms and their updraft winds,” NOAA says. “Older models assume the atmosphere experiences equal forces from above and below. This assumption can provide accurate prediction over large areas, but is unable to see the small-scale fluctuating winds that can lead to severe weather.”

The big question in Florida is how the FV3 will do with tropical storms and hurricanes. The GFS, along with the European forecast model (ECMWF), have always been the two go-to global forecast models used by meteorologists, not only at the National Weather Service but at the National Hurricane Center, particularly for developing storms.

Tropical Tidbits is a good resource if you want to see runs of the major forecasting models, including hurricane models once a system is identified as an invest. Click on “Global” models to check out the new FV3, as well as the GFS and European.


CFL forecast

(Image credit: NWS-Melbourne)

RAINFALL REPORT: Florida’s rainy season looks locked in, and it’s easy to see why June has the reputation as the wettest month in South Florida. After a dry start to the month, totals are building up from Miami to Tallahassee.

Monday’s notable rainfall totals via CoCoRaHS: Tarpon Springs, 3.66 inches; Brandon, 3.08; Hialeah, 2.34, northwest Tallahassee, 1.94; Atlantic Ridge State Preserve Park, Martin County, 1.03.

RECORD WATCH: Marathon’s record reports are like, a broken record. The low once again was only 86 on Monday, tying the record warm minimum for the month and beating the record for the date, which was 83 set in 2013. The high was 96, which also set a record.