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Isaias loses tropical characteristics...enters Canada

Isaias loses tropical characteristics...enters Canada
Advisory (2).jpg
Posted at 11:05 AM, Jul 28, 2020
and last updated 2020-08-04 23:05:55-04

FINAL UPDATE 8/4/20 11 PM

Isaias has transitioned to post-tropical and is weakening in Canada. The storm is no longer a threat to the U.S. This will be the final FOX 4 update on the storm.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

UPDATE 8/4/20 5 PM

Isaias is over eastern NY near Albany and will quickly move into Vermont shortly, then exit the U.S. before midnight tonight. Strong winds to tropical storm force continue from Long Island to New Hampshire. Torrential rainfall is leading to significant flooding in many areas of the Middle Atlantic and Northeast. The cleanup began early today across VA and NC due to several tornadoes that touched down last night and this morning, but the weather has significantly improved there. Tropical Storm Warnings remain in effect from northern parts of the Jersey Shore to downeast Maine. More wind damage and flooding will be possible through early Wednesday, but the rapid movement of Isaiais will take it out of the country later tonight.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

UPDATE 8/4/20 11 AM

Isaias continues to race northeast quickly along the I-95 corridor. The center is over the Eastern Shore of Maryland near Fredricktown or about 70 mi SW of Philly. The storm is rocketing northeast at 35 mph. The storm still has winds just shy of hurricane force despite having been over land for 12 hours. Part of the rest for this is its interaction with a strong jet stream now digging into the Middle Atlantic, part of the reason it is moving so fast. There have been reports of tornadoes and significant flooding in the Philadelphia area this morning. The threat will lift into the NYC Metro shortly and into Boston this evening.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

UPDATE 8/4/20 8 AM

At 800 AM, the center of Tropical Storm Isaias was located over southeastern Virginia. Isaias is moving toward the north-northeast near 33 mph, and this general motion accompanied by some additional increase in forward speed is expected through today. On the forecast track, the center of Isaias will continue to move near or along the coast of the mid-Atlantic states today, and move across the northeastern United States into southern Canada tonight. Maximum sustained winds are near 70 mph with higher gusts. Only gradual weakening is anticipated while Isaias moves north-northeastward near the mid-Atlantic coast today. A faster rate of weakening is expected to begin tonight, and the system is forecast to become post-tropical tonight or early Wednesday. Tropical-storm-force winds extend outward up to 140 miles from the center.

Sustained winds of 63 mph and a gust to 77 mph were recently reported at Third Island, Virginia, at the mouth of the Chesapeake Bay. The estimated minimum central pressure based on surface observations is 993 mb.

FOX 4 MORNING METEOROLOGIST TRENT ARIC

UPDATE 8/4/20 5 AM

The center of Tropical Storm Isaias is nearing southeast Virginia bringing strong winds, heavy rainfall and the threat of tornadoes along the Mid-Atlantic coast. The storm is rapidly moving NNE near 28mph.

Maximum sustained winds are near 70 mph with higher gusts and only gradual weakening is anticipated while Isaias moves north-northeastward today. A faster rate of weakening is expected to begin tonight, and the system is forecast to become post-tropical tonight or early Wednesday. Tropical-storm-force winds extend outward up to 140 miles from the center. The estimated minimum central pressure is 993 mb.

Sustained winds of 48 mph and a gust to 63 mph was recently reported at Duck, North Carolina. Sustained winds of 39 mph and a gust to 56 mph were also reported at Poquoson, Virginia. FOX 4 MORNING METEOROLOGIST TRENT ARIC

UPDATE 8/3/20 9 & 11 PM

Winds are now up to 85 mph with pressure down to 988 mb. Isaias will make landfall shortly near Oak Island NC. Significant storm surge threat and wind damage will be possible as the storm moves rapidly inland across eastern NC in the next few hours.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

UPDATE 8/3/20 8 PM

Isaias regained hurricane status and is racing toward the NC/SC border. Tropical storm conditions are lashing the Carolina coasts. A period of hurricane conditions is expected tonight near the center across eastern NC. A tornado threat will increase later tonight across eastern NC as the shear profiles are becoming more favorable for rotating storms in the feeder bands rotating in from the Atlantic. A persistent easterly fetch will create significant flooding along the Cape Fear and Neuse River. Rain totals will exceed 6" in some areas. The storm will move into Virginia by Tuesday morning with tropical storm conditions likely along I-95 Tuesday and Wednesday all the way into New England.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

UPDATE 8/3/20 11 AM

Isaias is expected to make landfall later tonight or early Tuesday along the coast of the Carolinas. The storm will bring tropical storm conditions to northeast South Carolina, eastern North Carolina and much of the I-95 corridor through Wednesday.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

UPDATE 8/3/20 8 AM

At 800 AM, the center of Tropical Storm Isaias was located by an Air Force Reserve reconnaissance aircraft and NOAA Doppler weather radars near latitude 30.2 North, longitude 80.1 West. Isaias has picked up a little speed and is now moving toward the north near 13 mph. Maximum sustained winds are near 70 mph with higher gusts. Some strengthening is anticipated today, and Isaias is forecast to regain hurricane strength before it reaches the coast of northeastern South Carolina or southern North Carolina tonight.

Tropical-storm-force winds extend outward up to 125 miles from the center. During the past hour a wind gust to 40 mph was observed at the St, Augustine Pier, Florida, and a sustained wind of 34 mph and a gust to 40 mph were measured by a Weatherflow station at the Jacksonville Beach Pier, Florida. The estimated minimum central pressure is 994 mb (29.36 inches).

FOX 4 MORNING METEOROLOGIST TRENT ARIC

UPDATE 8/3/20 5 AM

Isaias is forecast to become a hurricane later today and that has prompted Hurricane Warnings for parts of the North and South Carolina coast.

At 5:00 AM, the center of Tropical Storm Isaias is located off the northeast coast of Florida and is moving toward the north near 9 mph. A turn toward the north and north-northeast along with an increase in forward speed is expected later today and Tuesday. On the forecast track, the center of Isaias will pass well east of the Georgia coast through this morning. The center of Isaias will then approach the coast of northeastern South Carolina and southern North Carolina within the hurricane warning area later today. The center will then move inland over eastern North Carolina tonight and move along the coast of the mid-Atlantic states on Tuesday and into the northeastern United States by Tuesday night.

Maximum sustained winds are near 70 mph. Some strengthening is anticipated today, and Isaias is forecast to regain hurricane strength before it reaches the coast of northeastern South Carolina or southern North Carolina tonight. Slow weakening is forecast after Isaias makes landfall in the Carolinas and moves across the U.S. mid-Atlantic region tonight and Tuesday.

Tropical-storm-force winds extend outward up to 125 miles from the center.
The estimated minimum central pressure is 994 mb (29.36 inches).

FOX 4 MORNING METEOROLOGIST TRENT ARIC

UPDATE 8/2/20 11 PM

Tropical storm Isaias isn't showing much change beside the fact that its central pressure increased to 995 mb. It still has maximum sustained wind of 70 mph and is moving NNW at 9 mph. Rain and storms are now wrapping around the west side of Isaias, but it remains about 70 miles due east of the Space Coast so most of the rain is staying offshore. Tropical storm force wind gusts are still possible from the Space Coast to the Florida/Georgia line. Southwest Florida will experience a dry day Monday with typical rainy season conditions for the rest of the work week.

FOX 4 METEOROLOGIST ERIC STONE

UPDATE 8/2/20 8 PM

Not much has changed with Isaias over the past few hours as it makes its way to the southeast and east of the Space Coast. Rain bands continue to move in to eastern Florida and southwest Florida, but bands have been weakening and will continue to do so over our area tonight. The breeze is subsiding as well as we can expect 5-10 mph wind overnight into Monday morning. The next complete update will be at 11 PM.

FOX 4 METEOROLOGIST ERIC STONE

UPDATE 8/2/20 5 PM

Isaias remains a tropical storm just under hurricane strength with maximum sustained wind of 70 mph. Its moving to the NNW and is expected to make a more northerly turn late tonight and turn to the northeast Monday afternoon. Isaias will parallel Florida's east coast not making landfall until it reaches the Carolinas on Tuesday and could briefly reach hurricane status once again sometime tomorrow. Breezy NW wind continues in SWFL around 10-20 mph gusting to 25. Rain bands will continue to move through the area into tonight bringing a total of a .25" to .75". We will return to an average rainy season pattern Monday.

Convection persists with Isaias as several rain bands have moved onshore of Florida's east coast. Also West Palm Beach and Melbourne have experienced wind gusts at or near tropical storm force. This will continue until the storm moves northward early Monday morning.

FOX 4 METEOROLOGIST ERIC STONE

UPDATE 8/2/20 11 AM

Isaias has not strengthened and won't as it continues to head north. The turn NNW has occurred so the storm will parallel the FL coast keeping the strongest winds offshore and very near the coast. Expect partly to mostly cloudy skies in SWFL today with a few passing showers on the backside of the storm. Our winds will become westerly as the circulation lifts north. The storm will leave the area around Florida by Monday morning as it heads to Georgia and the Carolinas. As of the latest forecast track, the most likely area to see more significant impacts from Isaias will be eastern North Carolina and possibly parts of New England later this week.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

UPDATE 8/2/20 8 AM

Isaias continues to move NW at around 8 mph and is centered about 155 mi southeast of Cape Canaveral. The storm has seen a resurgence of thunderstorms near the center overnight but overall the storm has lost some intensity with winds down to 65 mph. All hurricane warnings have been dropped due to this weakening and it is unlikely the storm will regain strength given the forecast shear values. Tropical storm conditions remain close the Florida east coast and will affect parts of the area from the Space Coast northward to Jacksonville later today. The storm will exit the area by Monday morning.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

UPDATE 8/1/20 11 PM

Isaias remains a tropical storm with wind just below hurricane criteria at 70 mph. Its forward motion remains at 9 mph out of the northwest and has increased in pressure to 995 mb. Isaias should gain strength over the warm water of the Florida straights and return to a Category 1 hurricane sometime tonight. Strong southwesterly wind shear as well as dry air to its west is causing the deepest convection to for north and east of the storm. We will be on the western side of the storm which will be the much calmer side so expect rain bands to increase Sunday with wind speed of 10-20 mph with 20-30 mph near Lake Okeechobee. Gusty wind will also accompany rain bands.

FOX 4 METEOROLOGIST ERIC STONE

UPDATE 8/1/20 8 PM

Isaias remains a tropical storm with wind just below hurricane criteria at 70 mph. It has again slowed down, moving NW at 9 mph. Isaias should gain strength over the warm water of the Florida straights and return to a Category 1 hurricane sometime tonight. Rain bands have continued to move into SE Florida producing 1-2 inches of rain. Rainfall amounts less than .1 of an inch have been reported today in SWFL, but this will change as more bands move through our area tonight and tomorrow. Total rainfall will be a half to one inch through tomorrow. Wind this evening has been around 10-15 mph and will be around 10 overnight. Sunday will feature wind speed of 10-20 mph with 20-30 mph near Lake Okeechobee.

There has been no changes in hurricane and tropical storm warnings from the previous advisory. The next full update will be issued at 11 PM.

FOX 4 METEOROLOGIST ERIC STONE

UPDATE 8/1/20 5 PM

Isaias is now a tropical storm with maximum sustained wind of 70 mph. It is moving even slower at 10 mph to the NW and its central pressure has gone up to 993 mb. It has weakened due to wind shear, dry air, and interaction with land. It is now over open water so it is expected to strengthen into a Category 1 hurricane before coming very close to Florida's east coast. Isaias moved a bit WNW before returning to a NW movement so the cone has shifted a bit to the west. It will be very close to making landfall on Florida's east coast Sunday afternoon before turning to the north then northeast Monday and into next week.

A Hurricane Warning remains in effect for Boca Raton to the Volusia/Flagler County Line in Florida. A Tropical Storm Warning is in effect for North of Ocean Reef to south of Boca Raton Florida, Lake Okeechobee, and Volusia/Flagler County Line to Ponte Vedra Beach Florida.

Wind continues to be 10-20 mph along the coast and 15-25 mph near Lake Okeechobee. A stronger rain band will move through SWFL this evening with more on the way tonight and Sunday.

FOX 4 METEOROLOGIST ERIC STONE

UPDATE 8/1/20 2 PM

Hurricane Isaias is now barely holding on to hurricane status as it continues to weaken. Maximum sustained wind is now at 75 mph and its central pressure has increased to 990 MB. It is now over the Florida straights so a slight intensification is possible although it strengthen much as it continues to encounter dry air and strong westerly wind shear.

Weak rain bands continue to move through inland SWFL before weakening east of our coast. Bands will gradually become stronger and make their way across the SWFL coast as Isaias moves closer to Florida's east coast. Wind speed early this afternoon has been around 10-15 mph in many areas of SWFL and could become a bit stronger, up to 20 mph as the storm moves closer.

FOX 4 METEOROLOGIST ERIC STONE

UPDATE 8/1/20 11 AM

Hurricane Isaias has lost strength and now has maximum sustained wind of 80 mph as its making landfall on Northern Andros Island in the Bahamas. Everything else about Isaias has stayed the same including the forecast cone and the watches and warnings for the state of Florida since the last update. Dry air and wind shear have made Isaias look disorganized on infrared satellite, but convection still exists around the center of the storm.

As it heads closer to the east coast of Florida later today and tonight we can expect breezy northeast wind of 10-20 mph with higher values near Lake Okeechobee. Rain bands continue to impact the southeast coast and head in our direction, but are very weak by the time they reach southwest Florida. Bands will become more abundant and hold together more later today and into Sunday.

FOX 4 METEOROLOGIST ERIC STONE

UPDATE 8/1/20 8 AM

Hurricane Isaias remains at 85 mph, but the central pressure lowered again to 987 mb. Its forward speed is still out of the NW at 12 mph and the forecast cone remains the same as the previous advisory. Dry air continues to wrap around the eastern side of the storm and westerly wind shear continues to blow cloud tops to its east. Isaias continues to move along the southwestern edge of a ridge and will begin to move to the north tomorrow and then northeast Monday along the Carolina coast.

Hurricane and tropical storm warnings are in effect for the same areas of eastern Florida and Lake Okeechobee respectively as the previous advisory.

FOX 4 METEOROLOGIST ERIC STONE

UPDATE 8/1/20 5 AM

The track of Isaias has moved back to the east a bit taking the storm close to Florida's east coast late Saturday and early Sunday. The storm strengthened a bit over the past few hours as the central pressure dropped to 988 mb. Maximum sustained wind is now at 85 mph and it has slowed a bit, moving to the northwest at 12 mph. Dry air has wrapped around the east side of the storm. This as well as strong westerly wind shear should prevent Isaias from strengthening much more.

A Hurricane Warning is in effect for Boca Raton to the Volusia/Flagler County Line and a Hurricane Watch is in effect for Hallandale Beach to south of Boca Raton Florida. A tropical storm warning remains in effect for Lake Okeechobee.

Rain bands will move through SWFL later this afternoon through Sunday before the storm moves to our northeast. We can expect wind speed of 10-20 mph along the SWFL coast and near tropical storm force wind speed in and around Lake Okeechobee.

FOX 4 METEOROLOGIST ERIC STONE

UPDATE 7/31/20 11 PM

No changes to the forecast. Winds remain at 80 mph. The storm is fighting dry air and wind shear from the southwest which should prevent rapid intensification. The storm is expected to make a close approach to the coast or move inland across the Treasure Coast of Florida and then turn north up I-95 through Sunday night before exiting the state. The weather for SWFL this weekend looks fine... with gusty north winds later Saturday....and gusty west winds on Sunday with a few storms. Aside from that, no big changes to our weather is expected.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

UPDATE 7/31/20 8 PM

Isaias continues to move through the Bahamas and has strengthened some. Max winds are now at 80 mph and the pressure is down to 987 mb. Additional modest strengthening is possible through Saturday as it heads north through the islands. Southwesterly shear continues to impact the storm by injecting mid-level dry air into the storm from the southwest. Not much has changed since our earlier projections. The latest Euro model is trying to bring the storm inland across Palm Beach Co. late Saturday night and Sunday morning as a hurricane then move it up the state into north Florida by Sunday afternoon with a turn back out over the Atlantic. New Full advisory at 11 PM.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

UPDATE 7/31/20 5PM

The track of Isaias has moved slightly to the west taking the storm close to Florida's east coast late Saturday and early Sunday. The storm hasn't strengthened over the past few hours as the central pressure remains at 991 mb as it moves toward the NW at 15 mph. A Hurricane Warning is in effect for the east coast of Florida from Boca Raton to the Volusia/Brevard County Line. A Hurricane Watch is in effect from the Volusia/Brevard County Line to the Flagler/Volusia County Line and from south of Boca Raton to Hallendale Beach. A Tropical Storm Warning is now in effect for Lake Okeechobee.

Rain bands will move through SWFL Saturday and early Sunday before the storm moves to our northeast. We can expect wind speed of 10-20 mph along the SWFL coast and near tropical storm force wind speed in and around Lake Okeechobee.

FOX 4 METEOROLOGIST ERIC STONE

UPDATE 7/31/20 2PM

The only difference with this intermediate advisory on Hurricane Isaias is a slightly lower pressure, meaning a bit more organized than 3 hours ago. It may strengthen a bit over the next 24 hours, but strong south to southwesterly wind shear will limit the strengthening even though Isaias is over warm water.

As for Florida, a hurricane watch is in effect for parts of Florida's east coast from north of Deerfield Beach to the Volusia-Brevard County Line. A tropical storm watch is in effect for Lake Okeechobee. The next advisory and cone update will be at 5 PM.

FOX 4 METEOROLOGIST ERIC STONE

UPDATE 7/31/20 11 AM:

Isaias has weakened some and is battling some dry air and wind shear. Winds are down to 75 mph. The forecast track remains unchanged with the track and forecast cone remaining east of SWFL. There will be the chance we could see some of the outer bands from Isaias as it bypasses the area on Saturday, but besides that, the weather looks fine for this weekend as the storm will quickly move out of the area by Sunday. The worst weather will stay on the East Coast and offshore into the Atlantic over the northern Bahamas. Strong sinking air and subsequent compressional warming on the outer edge of Isaias will make for a hot day here in SWFL with highs in the mid 90s and heat index values close to 110. very typical in the day leading up to the arrival of a tropical system.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

UPDATE 7/31/20 8AM:

Hurricane Isaias is bringing strong winds and heavy rain to the southeastern parts of the Bahamas and the Turks and Caicos Islands. Maximum sustained winds coming in around 80 mph. Tropical Storm Watches remain in place for parts of the east coast of Florida. The track of the storm looks like it will continue to stick to the eastern part of the state through the weekend.

UPDATE 7/31/20 5AM:

Hurricane Isaias has slowed down just a tad and is currently located just southeast of Grand Inagua Island. Due to low wind shear, the storm is expected to become a Category 2 Hurricane as it moves through the Bahamas Saturday. However, the storm is projected to weaken as it inches closer to Florida. Tropical Storm Watches are in place for parts of the east coast of Florida. As for Southwest Florida, the storm track remains far enough east that our area shouldn't notice any significant impacts from the storm.

SPECIAL TROPICAL UPDATE 7/30/20 11: 40 PM

Isaias becomes a hurricane. Hurricane hunters have detected winds of 80 mph with Isaias just of the coast of the Dominican Republic. A Hurricane Warning is now in effect for the central and southern Bahamas.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

UPDATE 7/30/20 11 PM

Now that Isaias has left the Dominican Republic it is headed toward the Bahamas next. The storm has a chance for some modest strengthening as it heads northwest. Upper-level wind shear being created by a trough of low pressure will prevent more significant strengthening as it approaches Florida by Saturday. The storm is expected to remain offshore as it heads north. Tropical Storm Watches remain in effect from Miami-Dade to Indian River Co. It still looks like the storm will stay far enough east of our area that we will escape any significant weather from it, barring a major shift to the west, which is looking unlikely. The storm will then race northeast to affect the NC Outer Banks then New England by Tuesday.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

UPDATE 7/30/20 5PM

Now that Tropical Storm Isaias has made landfall in the Dominican Republic and is now moving to its north, its maximum wind speed remained the same at 60 mph and continues to move toward the NW at 20 mph. One again as expected the cone has shifted to the east. That is great news for SWFL. The latest forecast takes the storm several miles off Florida's east coast. The other change we see is Isaias is forecast to become a Category 1 hurricane by Saturday which is a bit stronger than previous forecast runs.

A trough moving into the east-central United States should cause Isaias to turn north-northwestward and northward as the western portion of the ridge erodes.

Most of the convection and strong thunderstorm activity is to its north and east and should move to our east which means this will provide little precipitation on our coast this weekend. Wind field of Isaias doesn't stretch as far to the west as it does to the north and east which also helps Southwest Florida's impact this weekend.

FOX 4 METEOROLOGIST ERIC STONE

UPDATE 7/30/20 2PM

Tropical Storm Isaias has now made landfall in the Dominican Republic. Tropical storm-force wind and heavy rain continues to better Hispaniola. Isaias still has a maximum sustained wind of 60 mph as it moves quickly to the northwest at 20 mph. The storm will continue on this path and eventually move northward and northeastward through a weakness in a ridge just east of Florida. Right now coastal SWFL is out of the cone and the forecast has Isaias moving just east of Florida's east coast. The next advisory and cone update will be at 5 PM.

FOX 4 METEOROLOGIST ERIC STONE

UPDATE 7/30/20 11 AM

Tropical Storm Isaias has winds of 60 mph and is inching closer to the Dominican Republic. Land interaction with the D.R. will likely take some steam out of Isaias before it emerges over very warm water close to the Turks and Caicos and the Bahamas. The storm is expected to ride around a large high pressure ridge over the Atlantic, the feature that has been steering it west this entire time. A weakness in the western edge of that ridge will cause the storm to turn northwest then north, then northeast near the southeast coast of Florida near Miami then ride around the edge of the high to the northeast just off the Carolina coast then into the Atlantic. The computer forecast models now have a firm handle of this eventual track and as a result, the NHC has shifted the track east with the cone now out of parts of SWFL near the coast. It is looking LESS likely we will see any big impacts from this system this weekend, but still prepare for a possible track change. Most of the bad weather with this system is on the north and east side, so a track to our east is VERY favorable for us. Next full update will come at 5 PM.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

UPDATE 7/30/20 5 AM:

Isaias will move across Hispaniola later today, however, the models tend to vary on what the Tropical Storm will do beyond that due to a tricky center. As the storm moves over land, the mountainous terrain should cause some weakening and disruption to the circulation. As the system moves through the Caribbean, it is expected to strengthen. The forecast cone continues to shift east and further changes to the storm's projected track are likely. Tropical storm watches have not been issued for Florida yet, but it is likely to happen, as parts of South Florida could start to experience Tropical Storm force winds overnight Friday into Saturday. It's still a little too early to get specific on potential impacts for Southwest Florida, but it's never to early to prepare. More details to come on-air and online.

FOX 4 FORECASTER LAUREN PETRELLI

UPDATE 7/29/20 11 PM

Tropical Storm Isaias has formed in the Caribbean after a big blow-up of thunderstorms near the center that finally tightened the circulation. The forecast track from the NHC has shifted east as reflected by the computer model forecasts this evening. The storm is still expected to maintain tropical storm strength as it heads north, and will still have to battle the high terrain of Hispaniola and then wind shear in the Caribbean. How it handles these two obstacles will be critical in its eventual strength. Tropical Storm Watches will likely be issued for parts of South Florida Thursday morning in anticipation of its arrival this weekend. Right now based on the latest forecast track the biggest impacts will be felt on the East Coast and offshore in the Atlantic, but if the storm strengthens and the wind field expands, even a storm tracking offshore or along the Florida East Coast will bring tropical storm conditions to a large part of South Florida. It's still too early to get specific on potential impacts. More updates to come

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

UPDATE 7/29/20 5PM

PTC 9 is located just to the south of Puerto Rico and continues to bring several inches of rain and tropical storm-force wind to the island. These conditions are also being seen in the U.S. and British Virgin islands. The system looks better organized and the system could acquire a well-defined center very soon. This would prompt the National Hurricane Center to name this Tropical Storm Isaias.

Maximum sustained wind remains at 45 mph and it continues to move quickly to the WNW at 23 mph. As the storm slows down it will become better organized, but land interaction and a strong southerly wind shear should prevent this storm from strengthening into a hurricane.

The cone has moved a bit to the east as most of the model plots are taking this storm toward the east coast of Florida this weekend. It looks like impacts of this storm for SWFL could be periods of heavy rain and windy conditions late this weekend, but there are many uncertainties with this storm. Stay tuned to Fox 4 on air and online for updates on this tropical system.

FOX 4 METEOROLOGIST ERIC STONE

7/29/20 2PM

Potential Tropical Cyclone 9 is still not a tropical storm as it has no circulation. It is moving quickly to the WNW at 23 mph. Once the storm slows down theres more of a chance a circulation will develop and we would have Tropical Storm Isaias as the maximum sustained wind is 45 mph. Right now the U.S. and British Virgin Islands as well as Puerto Rico and the Leeward Islands are experiencing heavy rain and strong gusty wind.

Tropical storm warnings are in effect from the Leeward Islands all the way through the southeastern Bahamas as this system is expected to move in a WNW direction over the next couple days. A turn to the NW is expected later in the week and into the weekend which models suggest. This would put the storm pretty close to SWFL late Saturday and into Sunday. There is still much uncertainty with this storm since its still an open wave. Interaction with land and a strong southerly wind shear will likely inhibit the strengthening of this storm.

A new cone will be generated at 5 PM with the next advisory update.

FOX 4 METEOROLOGIST ERIC STONE

7/29/20 11 AM

The forecast track with the 11 AM advisory has shifted south and west as a result of the more westward movement seen in PTC 9 than the models originally expected. The center still hasn't developed and tracking its exact movement will prove to be problematic until this happens. The latest forecast takes the storm directly across the D.R. and Haiti then brings in northward through the Florida Straits and into the eastern Gulf.

The forecast cone encompasses all of the state of Florida with the exception of the far western panhandle. Right now it appears that impacts could be felt in South Florida as early as midday Saturday with conditions deteriorating through the night into Sunday. Heavy rainfall that could lead to some flash flooding, strong winds, isolated tornadoes and coastal flooding will be possible if the current track from the NHC verifies.

The storm is expected to remain at tropical storm strength despite moving over very warm water due to expected disruptions in the circulation with land interaction with the D.R., Haiti and possibly Cuba. Also, wind shear will begin impacting the system later this week and that will act to both inject dry air into the system and try to rip the storm apart. These limiting factors are what is being reflected on the modest strength shown both in the models and the official NHC forecast.

This is subject to change, but future Isasis will have to overcome these obstacles to have a chance at being a more significant storm. The next update will be at 5 PM Eastern.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

7/29/20 8 AM

This morning, satellite shows that PTC 9 remains a trough of low pressure and has not developed a closed low-level center yet. The storm is still producing strong winds on its north side as it moves through the Lesser Antilles. Big thunderstorms have developed near the low-level center. The latest forecast cone shifts the track west and this is partly due to the fact that a strong northward component hasn't started yet. This WNW motion will continue for another couple of days with a more northerly component to the motion occurring by Friday. PTC 9 is a large storm. It is expected to officially become Tropical Storm Isaias later today with the potential from rain and wind impacts across South Florida by this weekend.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

7/28/20 11 PM

PTC #9 is moving very quickly...WNW at 25. It will be difficult to form a surface low pressure with it moving that speed, but it is expected to happen at some point in the next couple of days. When that occurs, we will have Tropical Storm Isaias. Most of the forecast models still are not bullish on developing this system into a significant storm, with most keeping it weak as it approaches South Florida this weekend.

There are several obstacles it will have to overcome in the coming days.

1. Dry air associated with the Saharan Air Layer that is located to the north of the system. Ingestion of this dry air will slow or halt any intensification of the system by disrupting the heat engine process that develops and strengthens tropical systems.

2. Wind shear associated with an upper trough over the western Atlantic. This trough will bring moderate southwest wind shear over the storm through Friday and this could prove to be a limiting factor.

3. Land interaction will be possible. Depending on where the eventual center forms, a track north of the islands of Hispaniola and Puerto Rico will allow it to avoid disruptive land interaction. If the center forms farther south, it has a higher chance of interacting with these features.

A storm that is weaker by the time points 2 and 3 become a factor will not be able to overcome those obstacles as easily as one that is stronger. Stronger storms can create their own environment and fight off any adverse effects more readily than a weaker storm.

So again, this is the part of the forecast where we sit, wait and watch to see what happens. Either way, just remain alert but do not panic. There are NO indications that we will have significant impacts here in South Florida from this system, but we still have a few days to watch it.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

7/28/20 5 PM

Not much has changed with this system as it continues moving west toward the Lesser Antilles. Convection associated with this tropical wave is very disorganized. It is TRYING to get its act together but is having issues with dry air and some wind shear. Hurricane Hunter aircraft have been flying around inside the system all afternoon and the storm has not reached to point where they can officially designate it a tropical storm. The latest forecasts keep the storm weak as it heads west toward the Bahamas by this weekend and eventually to South Florida. At this time, the storm will be a rain-maker to South Florida as it stands now with gusty winds based on the latest forecast track. There is a HIGH amount of uncertainty however as to how the storm will develop in the net 24-36 hours and how it will deal with the shear and dry air it will continue to face in the coming days.

As of now, there is absolutely nothing to be alarmed about with this storm. Always be prepared, but at this time we will continue to take a wait and see approach as it develops.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

FIRST UPDATE 7/28/20 11 AM

NHC begins issuing advisories on Potential Tropical Cyclone #9, a strong tropical wave located about 400 mi east of the Windward Islands. This tropical wave is showing signs of organization this morning, but the overall circulation is broad and elongated with two distinct areas of thunderstorms on its southwest and northeast side. The system continues moving west and will approach the Leeward Islands in a couple of days. Conditions are not perfect for further development as wind shear and dry air have been affecting the storm lately, but conditions are expected to improve as it moves away from the dry air currently in the Atlantic. Wind shear will likely remain an issue for it in the near-term, but conditions should become more favorable for further development once it nears the Bahamas.

Computer model forecasts vary from keeping the storm weak to strengthening it into a hurricane with a westward motion, then a turn toward the north as it approaches the U.S. It is still way too early to make a call on exactly what PTC 9 will do, and it will likely come down to a day-by-day analysis to determine the eventual outcome. Right now the official NHC forecast brings the storm into South Florida as a tropical storm this weekend. The forecast is highly uncertain and there is no cause for alarm, but as we always do in these situations, we'll watch it and adjust the forecast accordingly.

Regardless if it develops or affects the U.S., you need to be prepared for any storm this season, so take advantage of the quiet weather right now to make sure you have everything in order in case we have to deal with a storm down the road. We will keep you updated on PTC 9 in the coming days.

FOX 4 CHIEF METEOROLOGIST DEREK BEASLEY

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Tropical Storm WATCH: An announcement that tropical storm conditions (sustained winds of 39 to 73 mph) are possible within the specified coastal area within 48 hours.

Tropical Storm WARNING: An announcement that tropical storm conditions (sustained winds of 39 to 73 mph) are expected within the specified coastal area within 36 hours.

Hurricane WATCH: An announcement that hurricane conditions (sustained winds of 74 mph or higher) are possible somewhere within the specified coastal area. A hurricane watch is issued 48 hours in advance of the anticipated onset of tropical-storm-force winds.

Hurricane WARNING: An announcement that hurricane conditions (sustained winds of 74 mph or higher) are expected somewhere within the specified coastal area. A hurricane warning is issued 36 hours in advance of the anticipated onset of tropical-storm-force winds.