Will Matthew Cause Mayhem?

By now you’ve probably heard, there’s a new storm in the Atlantic, and it’s named Matthew. OK, you probably knew that, because the hype machine from the media has gone into overdrive for the past few days. Why has that happened? Some of the computer forecast models have indicated that there’s a possibility that Matthew could hit the East Coast? How likely is that? We’ll delve into that shortly. First, we’ll get into what we do know.

Satellite loop of Hurricane Matthew from Friday afternoon September 30. Loop provided by NOAA.

As of 2pm EDT on Friday, Matthew was a Category 3 Hurricane on the Saffir-Simpson scale, with maximum sustained winds of 120 mph.The storm was centered a little less than 100 miles off the northern coast of Colombia, and was moving off towards the west-southwest at 12 mph. A Tropical Storm Warning is in effect for the coast of Colombia from the Colombia/Venezuela border to Riohacha.

It is actually pretty rare to have a storm impact the ABC Islands (Aruba, Bonaire, Curacao) and northern South America. There have been a few wind gusts to near tropical storm force in Aruba and Bonaire today, but for the most part, it’s just been a breezy and cloudy day in an area that usually is sunny and warm. When Matthew crossed the island of Martinique a few nights ago, it produced sustained winds of 40 mph and a gust to 60 mph at the airport in St. Pierre, with reports of gusts of up to 89 mph on the island. There was several reports of damage across the island.

OK, that’s what we know. Here’s what we’re fairly sure about. Matthew should turn more towards the northwest and eventually north this weekend with some more strengthening possible. It may become a category 4 hurricane. Unfortunately, it is also going to pass very close to Jamaica late Sunday and early Monday. It may even make landfall on the island. Even a glancing blow will likely result in widespread damage across the island. After that, Matthew should continue northward, and it will pass very near or over extreme western Haiti or eastern Cuba before heading into the Bahamas. Some slight weakening is possible due to interaction with the land areas, but Matthew should still be a strong hurricane (Category 2 or 3) when it enters the Bahamas.

GFS model forecast for sea-level pressure and wind speeds for Monday morning October 3. That wouldn’t be a good time to be in Kingston, Jamaica. Image provided by WeatherBell.

Now, the part that nobody knows with any certainty – what happens after Matthew gets into the Bahamas. This is the big question, and a lot of it has to do with what the upper-level pattern looks like. A trough of low pressure will be starting to move out of the Northeast while another one moves into the Great Plains. In between, a ridge of high pressure will be moving into the East. Exactly how quickly these features move eastward will determine which way Matthew goes.

Forecast tracks for Matthew from the GFS Ensemble. Image provided by Brian Tang, University at Albany
Forecast tracks for Matthew from the ECMWF Ensemble. Image provided by Brian Tang, University at Albany

As you can see from the images above, there are dozens of possibilities as to where Matthew can go. Based on the most recent model runs, a track through the Bahamas and then northward off the Carolinas is the most likely outcome, but there are still some models that have the storm stall in the Bahamas or even drift closer to Florida or possibly into the Gulf of Mexico. Once it gets up towards the Carolinas, there are even more possibilities to consider. The storm could continue up the coast and threaten the Northeast. It could start to turn northeastward and threaten Atlantic Canada. It could head harmlessly out to sea. At least one model shows it doing nearly all of the above! This model has it head out to sea, then hook back northwestward, and head towards eastern New England and Nova Scotia/New Brunswick.

At this point, we really have to wait and see how the pattern evolves before we’ll have a better idea as to what Matthew is going to do. If it is going to impact the Northeast, the time frame would be towards next weekend.So, keep an eye on Matthew’s progress if you have plans for that time frame.

Beneficial Rain Is On The Way….Or Is It?

If you’ve lived around here long enough, at some point you start to think to yourself that winter won’t ever end. You start to dream about vacations in tropical locations, or better yet, sitting in your own backyard on a sunny summer afternoon. This past summer, you probably didn’t have many complaints, as there were plenty of those sunny, warm afternoons to go around. However, because it was so sunny and warm, much of the region is now in the midst of a very serious drought.

Yup, it’s been really dry for a while now. Image provided by the National Drought Monitor.

A persistent ridge of high pressure kept the Northeast dry and warm through much of the Spring and Summer. Most of the cold fronts that tried to move through the region were starved for moisture, thus their main effects were to cool temperatures and lower humidity for a day or two. Thunderstorm activity was common, but aside from localized downpours, there really hasn’t been a widespread heavy rain event across much of the region for several months. That could be changing this week.

GFS forecast showing an upper-level low pressure area sitting over the Appalachians Friday morning. Image provided by Pivotal Weather.

A slow-moving cold front will move across the region on Tuesday, bringing showers with it. While the rain likely won’t be too heavy, it should be widespread, which is good news for an area that needs all the rain it can get. The front will likely stall out right along the coastal plain, which may keep the shower activity going into Wednesday right along the coast. However, changes in the weather pattern are coming that promise to bring even more rain to the area.

An upper-level low pressure system will drop southward from the Great Lakes and take up residence across portions of the Ohio Valley and Appalachians. It will likely stay there for several days, before lifting out to the northeast this weekend. However, with the upper-level low pressure area just sitting there, low pressure will essentially remain in place at the surface as well across the same area. This will result in periods of rain and showers across much of the area right through the week. While the rain may be briefly heavy at times, persistent rainfall over several days can add up, with some areas possibly receiving 1-3 inches of rain between Tuesday and Friday, with some heavier amounts possible. Rainfall deficits in this area are on the order of 5-10 inches, so much more is needed, but this is definitely a good start.

GFS model forecast for rainfall through Saturday morning. Doesn’t look good for Northern New England. Around here? We’ll see. Image provided by Pivotal Weather.

So, if you’re in places like Pittsburgh, Syracuse, or Atlantic City, it’s going to be a pretty dismal week. Around here? Well, that’s not an easy question to answer. With the low setting up well to the southwest of the area, high pressure will try to build in from the north. This will bring cool and dry conditions into much of northern New England this week. As for southern New England, where the effects of the drought are the most pronounced, the forecast depends entirely on where the low and high set themselves up. If the high is the dominant feature, much of southern New England can expect dry and cool conditions, with gusty east to northeasterly winds bringing some clouds and drizzle in off the Atlantic at times. If the low sets up a bit closer to the region, then the forecast will trend more towards a damp scenario with periods of showers for the next several days. At this point, it’s still a little too early to tell which scenario will be the correct one. The pattern for the past several months would suggest that we stay drier. However, given what normally happens this time of year, and how the forecasts related to upper-level low pressure areas never go as planned, we wouldn’t be surprised at all if it ends up being a gray, damp week around here too. However, that’s by no means a certainty, so keep an eye on the forecast before you make any plans.

Weekly Outlook: September 26-October 2, 2016

Fall is definitely in the air as we start this week, with some frost in places to start the day. With the change in seasons, we may start to see a change in the pattern too, but there is plenty of uncertainty that goes with that. We are fairly certain about what will happen for the next few days though. High pressure moves offshore today with sunshine and seasonably cool temperatures once again. A cold front moves in tomorrow, with some showers likely. After that, things get quite tricky.

Cutoff low pressure systems are notoriously tricky to forecast and usually keep us cool and damp. This one might do just that. Image provided by Pivotal Weather.

That cold front will likely stall out near or just south of New England, and high pressure will try to build in from the north. At the same time, and upper-level low pressure system will settle into the Appalachians and remain in place for much of the rest of the week. Exactly where it sets up has big implications on the forecast though.If the high is able to build in enough, we’ll stay mostly dry, albeit it cool and breezy with an easterly flow bringing in some drizzle at times off the Atlantic. If the low sets up a bit farther north, we may have to deal with episodes of showers from Wednesday right through to the weekend. At this point, we’re not completely sure which way is right, so this is a low confidence forecast. Recent history says we stay dry, but climatology and the normal tendencies with the models say we more than likely would be cool and damp. For now, that’s the direction we’re leaning, but keep in mind, things could end up considerably different.

Frost advisories and freeze warnings are in effect this morning across much of the Northeast. Image provided by NOAA.

Monday: Sunny and chilly to start the day, but clouds start to filter in during the afternoon. High 61-68.

Monday night: Becoming cloudy with showers developing after midnight.Low 51-58.

Tuesday: Showers taper off and end from northwest to southeast, lingering longest near the south coast. Some sunshine may develop late in the day across the interior. High 67-74.

Tuesday night: Clearing skies well inland, remaining partly to mostly cloudy near the coast, with a few showers still possible across the Cape. Low 49-56.

Wednesday: More clouds than sunshine, a few spotty showers or drizzle may develop, especially near the south coast. High 63-70.

Thursday: Mostly cloudy and breezy with showers possible. High 61-68.

Friday: Cloudy and breezy with more showers and drizzle possible. High 60-67.

Saturday: Intervals of clouds and sunshine, chance for more showers. High 63-70.

Sunday: A mix of sun and clouds, chance for some showers. High 62-69.

On another note, keep an eye on the tropics. There’s a disturbance that’s about 1300 miles east-southeast of the Lesser Antilles early this morning that bears watching. There’s a decent chance it could become a tropical depression later this week before moving into the Caribbean. Once it gets into the Caribbean, some models show some modest strengthening, while others develop the storm into a monster (see below). It’s what the storm does more than a week out (assuming it develops) that bears watching. Some models have it keep cruising west-northwestward across the Caribbean and into the Gulf of Mexico, and from there who knows. That would be bad for a lot of reasons. One silver lining though would be that after it moves inland and weakens it could bring us some beneficial rainfall. Other models have it turn northward, cross Hispaniola or Cuba, then head out into the open Atlantic. Still, there are other models that have it cross Hispaniola, then head northward, up the East Coast. We don’t have to explain to you why that wouldn’t be good at all. While the odds of this system doing anything up here are fairly remote, there’s a chance that it could impact the US at some point. Again, don’t worry too much, but keep an eye on what this system does, if it does anything at all.

Computer model forecasts for the track of a tropical disturbance in the Central Atlantic. Image provided by Tropical Tidbits.
Computer model forecasts for the intensity of a tropical disturbance in the Central Atlantic. Image provided by Tropical Tidbits.

Weekly Outlook: September 19-25, 2016

Do not panic! Water is going to fall from the sky today. This is actually a normal circumstance. We haven’t seen it happen that much in the past several months, but it does actually happen from time to time. There’s even a technical term for it – “Rain”.

We really need this rain, as the drought we’re in just keeps getting worse and worse. Much of the region is now in severe or extreme drought, and while today’s rain will help, it will barely put a dent in it. What we need is numerous episodes of rainfall spread out over time, and the chances of that happening should start to improve as we head deeper into fall and winter.

How much rain we get today is still a big question mark, as you can see by these two model forecasts. We could get a little, we could get a lot. At least we’ll get some rain. Of course, after today’s rain, we probably won’t see much more until a cold front comes through Friday night. Before that, we’ll have high pressure bringing us dry and warm weather once again. As for next weekend, once the front goes through, high pressure returns with more dry weather. Notice that we didn’t say more “dry and warm” weather. That’s because next weekend looks significantly cooler. How much cooler? How does highs in the 60s and lows in the 40s sound? It sounds like late September to us. While these temperatures are actually a little below normal, given how warm the past few months have been, it’ll feel like it’s a lot cooler than it really is.

Latest drought update showing Severe to Extreme Drought across much of central and Southern New England. Image provided by US Department of Agriculture.

Monday: Cloudy with periods of rain and showers expected. Some localized downpours are possible. High 71-78.

Monday night: Mostly cloudy with rain tapering off and ending. Low 60-67.

Tuesday: Becoming partly to mostly sunny. High 78-85.

Tuesday night: Clear to partly cloudy.Low 57-64.

Wednesday: Sunshine and a few clouds.High 76-83.

Thursday: Partly to mostly sunny. High 75-82.

Friday: Increasing clouds, showers are possible late in the day and at night. High 77-84.

Saturday: Intervals of clouds and sunshine, just a slight chance for an afternoon shower.  High 64-71.

Sunday:Partly to mostly sunny. High 61-68.

Finally, because we like to entertain you at times, but also let you know what’s coming, we decided to end this week’s outlook with a good laugh for everyone. There’s a model called the CFS. It’s used for long-range forecasting, and it’s really not that good. However, sometimes, it’s fun to look at. While most models only go out a few days, we have a few that go out 10 to 16 days. This model however, goes out months. On one site that we use to look at this model, it goes out 32 days. Today’s Day-32 map was quite interesting, and is not likely to happen, but what the heck, let’s have some fun.

CFS model forecast for the morning of October 20. Yes, that’s a wintry mix across much of New England as a powerful coastal storm passes close to Nantucket. No, we don’t believe it either. Image provided by Pivotal Weather.

Ready or Not, Here Comes Fall

“Summer’s going fast, nights growing colder”

Rush wrote that lyric for the song “Time Stand Still”, and it’s pretty obvious they were talking about September. No matter how you define it, summer is either just about over, or already is. Astronomical fall begins on September 22 at 10:21am EDT, but meteorological fall is defined as the period between September 1 through November 30. For some people, summer ends of Labor Day or when football starts up. No matter your definition, we’re at that time of year. While it can and does still feel like summer across parts of the nation, there are more and more signs that summer is winding down.

As the nights start to grow a little longer the farther north you go, the cooler air starts to build up a little more, especially as you head into Canada and Alaska. The cold fronts that drop down from Canada and into the Northern US start to pack a little more punch. One of those fronts is moving across portions of the Upper Midwest and the Great Plains today. The airmass moving into the Rockies and Northern Plains behind the front is sending temperatures as much as 15 to 25 degrees below normal this afternoon.

Temperatures are 15-25 degrees below normal in the Northern Rockies and Northern Plains today. Image provided by Pivotal Weather.

As that airmass settles in, low temperatures will drop into the 30s and 40s across the Northern Plains and Rockies tonight. Frost advisories and freeze warnings have been posted for western portions of North Dakota for Tuesday morning. By Wednesday morning, the coldest air will move over Minnesota, where low temperatures could drop into the upper 20s and 30s. Additional frost and freeze advisories will likely be issued for this region.

A taste of things to come soon. GFS model forecast for low temperatures across Minnesota Wednesday morning. Image provided by WeatherBell.

Cold temperatures aren’t the only noteworthy item with this cold front. As the cold air surges into the Rockies, precipitation will accompany it. That precipitation will likely fall as snow in many areas, mainly at elevations above 5000 feet. Across some of the higher peaks, more than a foot of snow could accumulate over the next day or two. Winter Weather Advisories have been issued for portions of northern Wyoming as a result.

GFS model forecast for snowfall through Wednesday morning. Image provided by WeatherBell.

Some snow is also possible across the higher elevations of the Sierra Nevada as the cooler air spreads into the West. While accumulations will be minor, this will likely be the first snowfall of the year for this region. Across the rest of the Golden State, temperatures will likely be 6 to 12 degrees below normal on Tuesday, with highs only in the 70s to lower 80s, a welcome change from the 90s and 100s they’ve had for most of the summer.

While this front will bring cooler air into our area later this week, one thing it won’t do unfortunately, is bring beneficial rainfall to the region. It will produce showers and some thunderstorms, and while a few of the storms may contain heavy downpours, they’ll be very localized. Across much of the region, rainfall totals will be generally under half an inch. This will do little to put a dent in the severe drought that much of the region is currently experiencing. Rainfall deficits of 5 to 10 inches below normal since the beginning of March are common across the region.We really need some rain, and there doesn’t look to be a lot of it on the horizon.

Rainfall deficits across the Northeast from March 1 through August 31. Image provided by the Northeast Regional Climate Center.

While this early taste of fall moving into much of the Northern US this week is not uncommon for mid-September, it might not be repeated much this fall. Long-range forecasts are showing the likelihood of a warmer than normal fall across much of the United States.

Weekly Outlook: September 12-18, 2016

It’s getting tough to find ways to say the same thing every week, but we’ll try. Most of the upcoming week will be dry, but unlike much of the past few months, temperatures will start to turn cooler. Of course, this is expected, since we’re into the middle of September already and it couldn’t stay hot forever.

The week will start off on a cool note, as high pressure builds in, but as it moves offshore, we’ll warm up for Tuesday and Wednesday. Humidity will make a comeback on Wednesday as well, but a cold front will start to approach from the west. That front may give us a few showers late Wednesday and Wednesday night, but a drought-busting rainfall is not expected. After that, high pressure comes back for the end of the week, and this time, it’ll turn even cooler. How cool? Throw a blanket on the bed, because a lot of us could wake up to lows in the 40s Friday morning.Temperatures warm up again next weekend, but another cold front will start to approach, and it could bring in some showers late Sunday.

GFS model forecast for low temperatures Friday morning. Image provided by WeatherBell.

Just remember, a couple of days of cool weather is expected at this time of year. Things could be a lot worse. Out in the Northern Rockies, over the next few days, some places, mainly above 5000 feet elevation could pick up a foot or more of snow. Yeah, you read that right.

GFS model forecast for snowfall through Tuesday evening across the Northern Rockies. Image provided by WeatherBell.


No snow here for quite some time, but here are the details for the next week:

Monday: Harris K. Telemacher said it best in “L.A. Story” – Sun! Sun! Sun! High 71-78.

Monday night: Clear skies. Low 52-59.

Tuesday: Sunshine and a few clouds. High 77-84.

Tuesday night: Clear to partly cloudy. Low 59-66.

Wednesday: Morning sunshine, then increasing clouds. A few showers are possible late in the day. Humid. High 81-88.

Thursday: Becoming mostly sunny. High 67-74.

Friday: Plenty of sunshine. High 70-77.

Saturday: A mix of sun and clouds.High 73-80.

Sunday: Becoming cloudy and breezy, showers are possible in the afternoon. High 74-81.



Weekly Outlook, September 5-11, 2016

While the forecast for the upcoming week seems like it should be complicated, in reality, it isn’t, even with a former hurricane sitting just a couple of hundred miles to the south.

Hermine mills around south of the region for a few days. This gives us gusty winds, and periodic episodes of showers and steady rain into Wednesday, especially along the south coast. By Thursday, Hermine finally starts to pull away, the sun comes out, and it gets hot and humid again (summer’s not quite over yet folks). A cold front moves through Thursday night, with a few showers and thunderstorms possible.It’ll still be warm for Friday and Saturday, but without the humidity as high pressure builds in. Another front starts to approach on Sunday. Heat and humidity return ahead of it, but showers and thunderstorms accompany it as it moves through late in the day.

The strongest winds from Hermine are expected later today when gusts of 30-50 mph are possible across much of the region. Image provided by WeatherBell.

Monday: Cloudy and breezy with occasional showers and periods of steady rain at times. High 68-75.

Monday night: Cloudy and breezy with more showers possible, especially closer to the south coast. Low 59-66.

Tuesday:Mostly cloudy and breezy, more episodes of showers are possible. High 70-77.

Tuesday night:Mostly cloudy, still breezy along the south coast. Some additional showers may move through. Low 62-69.

Wednesday:Mostly cloudy with some more showers possible, still breezy across the Cape. High 77-84.

Thursday: Becoming partly sunny and humid. Some showers and thunderstorms are possible in the evening and at night. High 84-91.

Friday: A mix of sunshine and clouds, drier. High 83-90.

Saturday:Mostly sunny. High 83-90.

Sunday: Increasing clouds with afternoon showers and thunderstorms possible. High 82-89.

What’s Going On With Hermine?

Labor Day Weekend is here, and the big question on everyone’s mind is “What is Hermine going to do?” We’ll try to answer that as best as we can right now.

Satellite loop of Hermine. Loop provided by NOAA.

First, we’ll give you the facts. As of 2pm EDT, Hermine was centered about 90 miles east of Duck, North Carolina, moving toward the east at 10 mph. Maximum sustained winds are near 70 mph. Hermine is now a “post-tropical” storm. What does that mean? Well, to start with, it means that’s it’s no longer tropical. It’s more like a typical Nor’easter that we see throughout the fall, winter, and spring. As you can see in the satellite loop above, most of the thunderstorm activity is now well north of the center of circulation. Tropical systems contain thunderstorm activity concentrated near the center of the storm.

Map showing current tropical storm watches and warnings as well as the extent of strong winds with Hermine. Image provided by the National Hurricane Center.

Despite the fact that Hermine is no longer tropical, Tropical Storm Warnings remain in effect for the East Coast from Ocracoke Inlet, North Carolina to Watch Hill, Rhode Island. A Tropical Storm Watch is in effect from Watch Hill up to Sagamore Beach, Massachusetts, which includes all of Cape Cod, the Islands, and the coast of Rhode Island.

So, if it’s no longer tropical, why are there tropical storm watches and warnings in effect? There are two reasons for this. The first, and simplest one, is the fact that there is a chance Hermine could re-acquire tropical characteristics as it sits over the warm waters of the Gulf Stream over the next few days. The other reason is related to Sandy. As you may recall, when Sandy slammed into New Jersey in 2012, there were no hurricane warnings in effect, despite the fact that Sandy was still a Category 1 hurricane while offshore. The reason there were not warnings was because Sandy was expected to become “post-tropical” before landfall, and the rules that the Hurricane Center had to abide by at the time did not allow them to issue watches/warnings if the system was not expected to impact the coast as a tropical system. (Yeah, we think it was stupid too.) So, they changed those rules, and this is the first test of them.

Computer model forecasts for the track of Hermine. Image provided by the University of Wisconsin.

So, what does the future actually hold for Hermine? Hermine will stall out east of the Delmarva Peninsula tonight and Sunday as it gets stuck under an upper-level low pressure system. It will then drift around south of Long Island for a few days. While it’s sitting over the warm water there, it could become a tropical system again (possibly even a hurricane), but that won’t last too long. Why? As it sits over the same area, it will churn up the waters, which will bring cooler water to the surface through a mechanism called “upwelling.” As this cooler water comes up, the system will lose the warm water it needs to sustain a tropical system, and then lose any tropical characteristics it may have gotten back. In other words, it’ll be “post-tropical” again.

Wave Watch model forecast for expected wave heights along the East Coast Monday morning. Image provided by WeatherBell.

In terms of sensible weather, Hermine is going to lay the smack down on the Mid-Atlantic states. Rough surf will pound the coast, especially in New Jersey, for several days, along with strong winds right along the coast. Wind gusts of 40-60 mph are expected along the Mid-Atlantic coast, along with some periods of rain, though the heaviest rain should stay off shore for the most part.

Expected rainfall through Thursday morning. Image provided by WeatherBell.

What about here in New England? We’re going to escape the brunt of it. There will be some very rough seas, starting on Sunday and likely continuing through at least Wednesday. It’s probably a good idea to stay out of the water if you’re heading to the beach, as the risk for rip currents will be high. Likewise, you probably don’t want to be heading out on a boat, with seas of 10-20 feet expected. If you’re taking one of the ferries to the Vineyard, Nantucket, or Block Island, there will likely be times where they have to cancel them due to rough seas. In terms of winds, the strong winds are likely right along the South Coast and across the Cape and Islands. Wind gusts of 30-40 mph or more are likely at times right through at least Tuesday. The bulk of the rain will stay to our south, but periodic showers and occasional batches of steady rain will come through at times over the next several days. The graphic above might be overdone in terms of how much rainfall we’ll get, but there will likely be some rain at times, especially the farther south you head.

Hermine likely won’t start to move out of the picture until the latter half of the week. Until then, we’ll just head to deal with clouds, periodic showers, occasionally strong winds, and rough surf for several days. In other words, it’ll feel like a typical April week, expect temperatures will be in the upper 60s and 70s instead of 40s and 50s.


Hurricane Hermine Heading Here?

(Note: This post was edited to reflect the fact that Hermine was upgraded to a hurricane at 3pm EDT)

We’re just about to start the Labor Day Weekend, traditionally summer’s last gasp around here, and the big question on everyone’s mind is “Will Hurricane Hermine ruin my plans?” The short answer is “maybe.”

Satellite loop of Tropical Storm Hermine. Loop provided by NOAA.

First, let’s start off with the basic facts. As of 3pm EDT, Hurricane Hermine was centered about 115 miles south-southwest of Apalachicola, Florida, and was moving towards the north-northeast at 14 mph. The storm has maximum sustained winds of 75 mph, and some more strengthening is possible before landfall just east of Apalachicola tonight.A Hurricane Warning is in effect for the coast of Florida from Mexico Beach to the mouth of the Suwanee River. Hurricane watches and Tropical Storm Warnings are also in effect for much of the remainder of the Florida Gulf Coast, as well as much of the Atlantic Coast from northeastern Florida up to North Carolina.

Map showing the extent of tropical storm force winds with Hermine and all current watches and warnings. Image provided by the National Hurricane Center.

OK, now that we’ve got the facts spelled out, here’s what we’re fairly sure about: Hermine will likely make landfall a little east of Apalachicola, Florida tonight. This will be the 1st hurricane to make landfall in Florida since Hurricane Wilma on October 24, 2005, ending Florida’s record 11-year “hurricane drought.” Once it makes landfall it will move up across Georgia and into the Carolinas, slowly weakening while dropping heavy rainfall on the region. Flooding is almost a certainty in some areas. The center of Hermine should move back out into the Atlantic off the North Carolina coastline, possibly as far north as Norfolk, Virginia by late Saturday. Once off the coast, the storm will likely drift northward and then stall east of the Delmarva Peninsula on Sunday. This is where things get tricky.

Rainfall forecast through Monday morning. Image provided by WeatherBell.

We’ve gone over what is going on currently, and what we’re fairly sure will happen over the next 2-3 days. Now, we’ll delve into the parts that we don’t have a handle on yet. Once the storm stalls east of the Delmarva Peninsula, we have a lot of questions that just can’t be answered right now. Where does it actually stall? How long does it stall? Which way does it drift once it does stall? How strong will it be? How large will the wind field be? How large will the precipitation field be? These are all important details that have a HUGE effect on the forecast. Unfortunately, we won’t have a better idea of these details for another 24 or even 48 hours.

GFS Ensemble Forecast for the position of low pressure Monday morning. Note that while the different members all have the low positioned south of Long Island, there is some variation in all directions as to exactly where the storm will be centered. Image provided by WeatherBell.

While we’re not expecting Hermine to be a hurricane once its off the Delmarva Peninsula, it could still be a tropical storm once it is east of the Delmarva Peninsula. More likely, it will become extratropical. What does that mean? To put it in simple terms, it will be more like a typical Nor’easter around here.

If you’ve got Labor Day Weekend plans, don’t scrap them just yet, but have a backup plan ready. The farther north your plans are, the less likely that you’ll be impacted. However, the closer you are to the South Coast or the Cape, the greater the chance that you may be dealing with gusty winds and/or rainfall. (Rough surf is a virtual lock at this point, so staying out of the water is probably a good idea).

We should be able to provide an update this weekend, once things become a little more certain.