The Tropics Are Starting to Get Active

It’s been a very quiet hurricane season so far, not just in the Atlantic, but in the Pacific as well, but that appears to be changing.

It’s been a quiet season compared to normal across the Atlantic and Pacific this far. Image provided by Colorado State University.

The most immediate concern is Tropical Storm Dorian. As of 2pm Monday, Dorian was centered about 95 miles east-southeast of Barbados, and was moving towards the west-northwest at 14 mph. Dorian has maximum sustained winds near 60 mph, and additional strengthen is expected. Tropical Storm Watches and Warnings are in effect for much of the Lesser Antilles, and a Hurricane Watch is in effect for St. Lucia.

Tropical Storm Dorian is approaching the Lesser Antilles. Loop provided by NOAA.

Dorian is expected to pass very close to Barbados this evening, and then close to St. Lucia or St. Vincent overnight tonight or early Tuesday. Because Dorian is not that large, the worst effects (damaging winds, torrential rainfall) will likely be limited to these islands.

Model forecasts for the track of Tropical Storm Dorian. Image provided by Tropical Tidbits.

Once Dorian moves past the Lesser Antilles, the questions become tougher to answer. The official forecast from the National Hurricane Center calls for Dorian to become a hurricane and turn northwestward, passing close to western Puerto Rico on Wednesday and then eastern portions of Dominican Republic Wednesday night and early Thursday, with some weakening as it interacts with land. In terms of the track itself, most of the forecast models are clustered in this area, give or take 100 miles. The intensity forecast is the biggest question mark for now. The Hurricane Center is calling for the storm to have maximum sustained winds of 80 mph when it reaches Puerto Rico and Hispaniola. However, looking at the various models, they are showing that it could be as strong as a Category 3 system, or as weak as a tropical depression. Intensity forecasts are still the toughest part of forecasting tropical systems, and for a small storm that has dry air all around it, this one is especially tough. Frankly, at this point, we wouldn’t be surprised with any outcome.

Model forecasts for the intensity of Tropical Storm Dorian. Image provided by Tropical Tidbits.

What about when it gets beyond Hispaniola and Puerto Rico? The official track and the various models all show the storm heading into the Bahamas and possibly towards Florida or the Southeast. It is still WAY too early to speculate on that (but that won’t stop the hype machine from Twitter and the Facebook Forecasters). First, we need to see if Dorian even survives that long. The mountains in central Hispaniola rise as high as 10,000 feet. Many storms that cross this area get torn apart by the terrain and dissipate. If (and that’s a big “if”) it survives, we’ll have to see what kind of shape it’s in when it emerges into the Bahamas before we can assess it’s future. This is all presuming the storm turns northwestward and heads towards Puerto Rico and Hispaniola. There’s nothing that says it won’t continue westward and heads towards Cuba or Jamaica. Just because none of the computer models are forecasting it does not mean it can’t happen.

Meanwhile, off the East Coast, a low pressure system is developing about 300 miles southeast of Cape Hatteras, NC this afternoon. This system could become a tropical or subtropical storm later today or tomorrow. As we mentioned in our Weekly Outlook, while the system is expected to stay well offshore and not impact the East Coast, this is far from definite. Some of the forecast models this afternoon show some moisture from the system interacting with an approaching cold front to bring some rain into parts of eastern New England Wednesday night and Thursday. Obviously, this will depend on exactly where the system tracks.

Model forecasts for the track of a developing system off the East Coast. Image provided by the University of Wisconsin.

Whether or not the system has any impact on New England, it will likely bring some gusty winds and heavy rain to portions of Atlantic Canada toward the end of this week. Rainfall totals of 2-4 inches and locally heavier are possible along with winds gusts to 50 mph along the coast, possibly higher, depending on how strong the storm gets. While this seems like an average Nor’easter, it will come on the heels of a non-tropical system that will bring heavy rain and strong winds to the same area tonight into Wednesday. Not exactly an ideal ending to summer for parts of the region.

Weekly Outlook: August 26 – September 2, 2019

First, our apologies for the brief post last week and the missing temperatures in the forecast. We at Storm HQ were taking a cruise to Bermuda for a much-needed vacation, and our internet connection on the ship was even worse than expected. It took far too long to even get what we wrote posted. We’re back in the Storm HQ World Headquarters Compound now, so we’re back to full updates.

It’s a chilly start to the week, with many locations dropping into the 40s north and west of Boston this morning. Image provided by Weathermodels.com

As for the coming week and the upcoming Labor Day Weekend, we’ll start off with high pressure in control, providing the region with dry and cool conditions today, but a warming trend is expected over the next few days. Some low clouds may remain in place this morning along the coast, thanks to the onshore flow around the high pressure area to our north and a deepening system south of Nova Scotia. The high pressure system will eventually win out, with sunshine developing along the coast by afternoon as well.

A cold front will start to approach the region on Wednesday, which means we should turn warmer and more humid, but there’s a possible fly in the ointment. There’s a system off the Carolinas right now that could become a tropical or subtropical storm later today (we’ll likely have a special blog post about this storm and Dorian either later today or on Tuesday). Right now, this system looks like it will head towards the northeast, and stay well offshore, but that is not set in stone yet. A track more towards the north-northeast could bring it close enough to at least bring in some clouds to southeastern New England. A return of onshore flow would mitigate any warm and humid weather along the coast, and depending on how close the system passes, we could even see a few showers reach the Outer Cape and the Islands. Obviously, we’ll keep an eye on this situation over the next few days. We think it’s a low-probability that it has an impact on us, but that probability is nowhere near zero right now.

How close will a potential tropical system come to New England? Probably not close enough to have much impact, but it’s possible. Image provided by Tropical Tidbits.

Back to that cold front, it likely produce some showers and a few thunderstorms Wednesday night into Thursday before it moves offshore. High pressure builds in behind the front on Friday with some drier weather, but another cold front moves will approach on Saturday. This one doesn’t look like it will have much moisture to work with, so we’re only expecting a few showers. High pressure builds in behind the front with cooler weather on Sunday. For Labor Day on Monday, the “traditional end of summer”, it looks like we’ll turn a littler warmer again as the high starts to move offshore.

You’re probably wondering if we’re done with the heat for the year. The answer is “not likely”. We’ve had plenty of 90-degree days well into September (and on very rare occasions into October. In fact, at least one model is showing some very warm weather the following weekend, with temperatures well into the 80s and close to 90 again. It’s nearly 2 weeks away, so it’s hardly set in stone, but don’t take the air conditioner out of the window and out away your summer clothes just yet.

Could we have some heat return next weekend? One model thinks so. We’ll see what happens over the next 10 days. Image provided by WeatherBell.

Monday: Low clouds linger across southeastern Massachusetts in the morning, bright sunshine everywhere in the afternoon. High 68-75, coolest along the coast.

Monday night: Clear skies. Low 47-54, warmest in the urban areas.

Tuesday: Sunshine and some afternoon clouds. High 71-78.

Tuesday night: Mostly clear. Low 53-60.

Wednesday: Partly to mostly sunny. Clouds move in at night with some showers possible towards daybreak. High 75-82, a little cooler along the coast.

Thursday: Intervals of clouds and sunshine with scattered showers, possibly a thunderstorm, mainly during the morning. High 77-84.

Friday: Plenty of sun. High 78-85.

Saturday: Partly to mostly sunny, some showers are possible at night. High 79-86.

Sunday: A mix of sun and clouds. High 71-78, coolest along the coast.

Labor Day: A sunny start, then clouds move in. High 73-80.

Weekly Outlook: August 19-25, 2019

Since this forecast is being written from the North Atlantic (somewhere around 39N/73W), and after a few mojitos, we’ll keep it simple this week. The graphics and sarcasm will return next week.

Basically, we’ve got hot and humid conditions through Thursday with high pressure sitting offshore. A few showers and thunderstorms may pop up each day, but especially Wednesday and Thursday as a cold front moves through. High pressure then builds in with drier and cooler conditions for Friday and the weekend.

Monday: A mix of sun and clouds, a few showers and thunderstorms are possible.

Monday night: Partly cloudy, and showers or storms end in the evening.

Tuesday: Partly sunny, chance for an afternoon shower or thunderstorm.

Tuesday night: Partly cloudy.

Wednesday: Intervals of sun and clouds, showers and thunderstorms likely in the afternoon.

Thursday: More clouds than sun with scattered showers and thunderstorms.

Friday: A mix of sun and clouds.

Saturday: Plenty of sunshine.

Sunday: Partly to mostly sunny.

Weekly Outlook: August 12-18, 2019

After a pretty- good weekend weatherwise, we’ve got another decent day today, though humidity levels will start to creep up. After that, there’s some rain in our future.

High pressure remains in control today, but it will be offshore, so we’ll see moisture start to move into the region. You’ll notice it both at the surface, where dewpoints will start to creep up, and later of aloft, as some clouds start to move into the region. A few showers are possible Monday night as a cold front starts to approach the region, but the bulk of the activity will wait until Tuesday when the front moves through. Some thunderstorms are also possible, especially towards the South Coast where there is the potential for some heavy downpours.

This may be a bit too much, but the NAM continues to insist on some very heavy rainfall along the South Coast from Tuesday’s system. Image provided by WeatherBell.

The front pushes offshore Tuesday night then stalls south of New England while high pressure tries to build in to the north. As a result, we may have clouds lingering near the south coast while sunshine dominates farther north.

High pressure building in behind the front could send temperatures into the 40s across much of Northern New England Wednesday morning. Image provided by Weathermodels.com

Another weak disturbance will move through on Thursday with some additional clouds and possibly a few more showers, then high pressure builds in for Friday and the weekend with conditions fairly similar to what we just had this past weekend. This also includes the chance for a few widely scattered pop-up showers. These won’t be an issue for 90-95% of the region, but if you’re one of the unlucky 5-10%, they won’t last too long and shouldn’t be that heavy. Certainly nothing to cancel any plans over.

While we’re talking about next weekend, we just wanted to let you know that next week’s outlook will likely be posted at some point next Sunday morning, and not early Monday morning as usual. We’ll return to the Monday morning posting the following week.

Monday: Morning sunshine starts to fade behind increasing high clouds in the afternoon, becoming humid. High 80-87.

Monday night: Becoming mostly cloudy with a few showers possible, especially across southern New Hampshire and northern Massachusetts. Low 64-71.

Tuesday: Mostly cloudy with scattered showers and thunderstorm. High 77-84.

Tuesday night: Mostly cloudy with scattered showers and thunderstorms lingering across the South Coast and Cape Cod through midnight. Skies may start to clear out after midnight north of the Mass Pike. Low 59-66.

Wednesday: Partly to mostly sunny from the Merrimack Valley northward, intervals of clouds and sunshine elsewhere. High 73-80, coolest along the coast.

Thursday: A mix of sun and clouds, chance for a shower or two. High 72-79.

Friday: Sunshine and some afternoon clouds, slight chance for a shower. High 74-81.

Saturday: Partly to mostly sunny, just a very slight chance for a pop-up shower. High 77-84.

Sunday: Sunshine and some afternoon clouds, but a stray shower is possible again. High 79-86.

Weekly Outlook: August 5-11, 2019

We’ve actually got some fairly typical summer-time weather coming up for most of the week. Nothing too extreme, just warm and humid weather for a few days with a daily chance for thunderstorms, followed by cooler and drier weather late in the week.

We start the week off with a cold front pushing farther offshore and high pressure building in today. This will result in seasonably warm temperatures and low humidity. This won’t last long, as a warm front will move through Monday night and early Tuesday. This will allow more humid air to settle back in on Tuesday. With the warm and humid air in place, a few showers and thunderstorms may develop Tuesday afternoon.

Dewpoints will be mainly in the 50s across the region this afternoon. Image provided by Weathermodels.com

As we get into Wednesday, a slow-moving cold front will start to approach from the west. The front likely won’t move through until Thursday night or Friday morning, but again, we’ll have warm and humid conditions in place, and the approaching front will help to trigger showers and thunderstorms both Wednesday afternoon and again Thursday afternoon. Some of these storms could become strong to severe, with gusty winds, hail and heavy downpours in some of the stronger storms. It’s not going to rain all day, but if you’ve got outdoor plans Wednesday and Thursday, keep an eye to the sky during the afternoon and evening both days.

Thunderstorms could drop some heavy rainfall on the region during the middle of the week. Image provided by WeatherBell.

The front finally pushes through early Friday, but an upper-level low pressure area will move across the Northeast. So, even though we’ll have some drier air moving in, a few pop-up showers and thunderstorms will be possible once again. High pressure then builds in for the weekend with cooler and drier conditions. In fact, temperatures could even end up a little below normal.

An upper-level low pressure area will help usher in some cooler weather for Friday and the weekend, Image provided by Pivotal Weather.

Monday: Sunshine and a few afternoon clouds. High 79-86.

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

Tuesday: Partly sunny and becoming humid, chance for a few showers and thunderstorms during the afternoon. High 80-87.

Tuesday night: Partly to mostly cloudy, some additional showers and storms are possible, mainly in the evening. Low 64-71.

Wednesday: Intervals of clouds and sunshine with scattered showers and thunderstorms developing. High 80-87.

Thursday: Partly sunny with another round of showers and thunderstorms possible. High 81-88.

Friday: Sunshine and some afternoon clouds, breezy, slight chance for a shower or thunderstorm. High 78-85.

Saturday: A mix of sun and clouds. High 75-82.

Sunday: Partly to mostly sunny. High 76-83.

Weekly Outlook: July 29-August 4, 2019

It’s back! The heat and humidity has returned, much to the delight of some, and dismay of others (count us among the “others”). It won’t hang around for too long though, but there’s not exactly any “cool” weather in our future.

Heat Advisories have been issued for parts of the region for Monday and Tuesday (shaded in orange on the map). Image provided by the National Weather Service.

We start the week off with high pressure anchored off the East Coast. This will result in southwesterly winds pumping warm and humid air into the region for Monday and Tuesday. Many places will likely top 90 once again, and with dewpoints remaining high, heat indices could approach 100 during the afternoons. Heat Advisories have been posted for parts of our area.

The heat index will be in the middle to upper 90s across the region Tuesday afternoon. Make sure you’re prepared if you’ll be outside. Image provided by WeatherBell.

Some spotty relief is possible during the next couple of afternoons, as some showers and thunderstorms will likely develop each day. Some of these storms could produce hail, heavy downpours, and strong winds, but a widespread severe weather outbreak is not expected. Showers and storms will become more numerous on Wednesday as a cold front approaches the region. This front will be fairly weak, but it should push through by early Thursday. Behind it, some drier air will move in, along with slightly cooler conditions for Friday.

Dewpoints in the 50s on Friday is fine by us. Image provided by Weathermodels.com

Right now, next weekend looks like it will be a typical summer weekend across the area. We’ll have temperatures in the 80s, moderate humidity levels, and some pop-up showers and thunderstorms to contend with. Nothing to cancel plans over, but something you’ll need to keep an eye on if you plan to be outdoors.

Monday: Sunshine and some afternoon clouds, chance for a pop-up shower or thunderstorm. High 85-92.

Monday night: A shower or thunderstorm during the evening, otherwise becoming clear to partly cloudy and muggy. Low 66-73.

Tuesday: Partly to mostly sunny, breezy, humid, chance for a few pop-up showers or thunderstorms again. High 88-95, a little cooler along the south coast.

Tuesday night: Partly cloudy. Low 66-73.

Wednesday: Intervals of clouds and sunshine, showers and thunderstorms becoming more likely, especially from late afternoon into the overnight hours. High 83-90.

Thursday: Any lingering showers end early, then becoming partly to mostly sunny and less humid. High 80-87, coolest along the coast.

Friday: Sunshine and some afternoon clouds. High 79-86, coolest along the coast.

Saturday: A mix of sun and clouds, chance for an afternoon shower or thunderstorm. High 81-88.

Sunday: Partly sunny, a shower or thunderstorm is possible again. High 84-91, cooler along the coast.

Weekly Outlook: July 22-28, 2019

The heat and humidity are gone (for now), but some rain is in our immediate future, but much of this week should end up being rather nice.

A cold front moved across the region last night, bringing an end to our heat wave, and taking the humidity away as well. However, that front stalled out south of Long Island, and it will remain there today. It’ll still be warm today behind the front, but closer to what we should experience during the latter half of July. A wave of low pressure will ride along the front, and it will produce some showers and thunderstorms across the area this afternoon and evening. A few of these storms may contain gusty winds and heavy downpours, but a severe weather outbreak is not expected.

Some heavy rainfall amounts are possible over the next couple of days. Image provided by Weathermodels.com

A second wave of low pressure will ride along the front on Tuesday, bringing in another round of showers and thunderstorms. Some of these storms may produce heavy downpours, which could lead to some localized flooding. One other thing you’ll notice is that it will be much cooler with plenty of cloud cover for most of the day. Many places may stay in the upper 60s to lower 70s throughout the day.

At least one model keeps temperatures in the 60s all day on Tuesday. We don’t think it’ll be quite that cool, but it’s certainly possible. Image provided by WeatherBell.

The front sags a little more southward on Wednesday as another wave of low pressure rides along it. This one will likely stay too far south to have any impact on us, except possibly Nantucket and Martha’s Vineyard, but we’ll certainly keep an eye on it. For the rest of us, high pressure starts to build back in at the surface, but with an upper-level low pressure area moving through, we’ll see clouds sprout up in the afternoon, with a stray shower or thunderstorm not out of the question.

From Thursday through Sunday, high pressure will be in control with generally dry conditions. Temperatures will slowly warm up as we head through this period, as will humidity levels, but in general, they’ll be close to what you’d expect for late July, and nothing extreme like we just had this past weekend.

Monday: Some morning sunshine, then becoming mostly cloudy with some showers and thunderstorms developing in the afternoon. High 79-86.

Monday night: Cloudy and breezy with showers and thunderstorms likely, tapering off after midnight. Low 60-67.

Tuesday: Plenty of clouds with showers and thunderstorms redeveloping in the morning, tapering off late in the day. Some storms may contain heavy rainfall. High 68-75.

Tuesday night: Mostly cloudy. Low 57-64.

Wednesday: Lingering clouds early, especially along the South Coast, then becoming partly sunny. High 74-81.

Thursday: Sunshine and some afternoon clouds. High 78-85, coolest along the coast.

Friday: Mostly sunny. High 81-88.

Saturday: Plenty of sunshine. High 83-90.

Sunday: A mix of sun and clouds. High 84-91.

Here Comes the Heat

Excessive Heat Warnings and Heat Advisories are in effect right through the weekend across much of the Northeast. Image provided by Pivotal Weather.

We warned you in our Weekly Outlook that it was coming, and it’s just about here – some brutal heat and humidity is expected for the next few days.

High pressure at the surface and aloft will be responsible for our heat and humidity through the weekend. Image provided by Tropical Tidbits.

Friday will start out with some lingering clouds and a little fog, but the sun will return and as winds shift into the southwest, so will the heat and humidity. Many locations will reach 90 on Friday, but not everyone. Dewpoints will get into the lower 70s, sending the heat index well into the 90s across the region. At night, with plenty of humidity around, temperatures likely won’t drop below the middle 70s across the region, making for an uncomfortable sleeping night if you don’t have air conditioning. This sets the stage for Saturday.

Saturday will likely be the hottest day we’ve had around here in several years. Add in the high humidity (dewpoints again in the lower to middle 70s), and well, it’ll be downright brutal outside. Since it will already be warm to start, with plenty of sunshine, temperatures will quickly jump in the morning, with many locations likely reaching 90 by lunchtime, but it won’t stop there. Temperatures will likely get into the upper 90s, with some spots, especially in the Merrimack Valley, possibly topping 100 degrees.

It’s going to be hot on Saturday. Really hot (by New England standards). Image provided by WeatherBell.

How rare is a 100-degree reading? Since the Merrimack Valley is the likeliest spot, here is some data for Lowell. In the 131 years of temperature records for Lowell, the city has topped 100 degrees just 35 times, or about once every four years. However, it’s actually been 8 years since Lowell hit 100, with a high of 102 on July 22, 2011. Before that, you have to go back to 2002, when it hit 101 on August 14, and 100 on July 3. So that’s just 3 times in the past 17 years. Skewing that average of once every 4 years is the fact that Lowell reached 100 5 times in 1911, 4 times in 1949, and 5 times in 1952. That’s 14 among those 3 years alone. July 22, 2011 was also the last time it reached 100 at Logan Airport in Boston, where they’ve only hit 100 25 times in 147 years of records.

With temperatures in the upper 90s (or higher), and dewpoints in the lower to middle 70s, that means that the heat index will be in the range of 105 to 110 degrees or higher during the hottest part of the day. If you have any plans to be outside, whether it be by the pool, at the beach, at the NASCAR activities in Loudon, or anywhere else, make sure you try to stay hydrated, and take plenty of breaks in the shade if you can.

Heat indices will likely be well over 100 across most of the region Saturday afternoon. Image provided by Weathermodels.com

Saturday night will be another uncomfortable night, with low temperatures only dropping into the middle to upper 70s. Some of the urban locations, like Boston, may not drop below 80. This leads in to another brutally hot and humid day on Sunday. Once again, most places will likely reach 90 by lunchtime and keep going. High temperatures will again get into the upper 90s across the area, with some 100-degree readings possible. Dewpoints will remain in the upper 60s to lower 70s, so we’re looking at heat indices in the 105 to 110 degree range once again.

Sunday looks to be another scorcher, but we’re not quite convinced it will be as hot as this model is showing. Image provided by WeatherBell.

By late Sunday, a cold front will start to approach, and it may produce some showers and thunderstorms during the evening and overnight. Behind it, much more seasonable air and lower humidity settles in for Monday. There may be a little relief in spots before that as well. Thunderstorm complexes in the Midwest will ride along the top of the upper-level ridge, as it typical in the summer. Right now, it looks like this may happen both late Friday and late Saturday. Unfortunately, it looks like these may fizzle before reaching the Northeast, and if they don’t, they will likely pass southwest of our area. So, we’re not holding out hope for these to help cool us off.

Long range forecasts show that some heat may return late next week into next weekend, but not nearly to the extent of what we’ll be dealing with for the next few days.

Weekly Outlook: July 15-21, 2019

Some people do like it hot. Here at Storm HQ we’re not part of that group, but to each their own.

We’ve largely escaped it so far this summer, but it looks like we’ve got some real heat coming later this week. Before then, we’ve actually got a rather nice stretch of weather coming up.

The week starts off with high pressure in control for Monday with sunshine, warm temperatures, and low humidity levels, a perfect combination for mid-July. The high slides offshore on Tuesday, which will allow humidity levels to start to creep up a little bit. A warm front moves through Tuesday night, with a chance for a shower. By Wednesday, hot and humid air moves in, but it may also come with some showers and thunderstorms during the afternoon. We’re not looking at any severe weather, but it will take the edge off the heat in the afternoon, and also make it even more humid late in the Friday.

Thursday is looking like a fairly wet day right now. What’s left of Tropical Storm Barry will likely move across the region, with widespread showers and thunderstorms. Since it’s a tropical airmass, some of these storms may produce heavy rainfall. It’s not going to be the 10-20 inches they’re getting in the Lower Mississippi Valley, but may be enough to cause a few problems around here.

The heat index could be well over 100 Friday afternoon across most of the region. Image provided by Weathermodels.com

Once ex-Barry pulls away early Friday, things will get hot. It will also remain humid, which means Friday will be a good day to find some air conditioning. If you are going to be outside, make sure you drink plenty of liquids, and wear sunscreen. Temperatures will likely soar well into the middle to perhaps upper 90s across the area. Friday night is looking rather ugly as well for sleeping, as much of the region may not drop below the upper 70s. Some of the cities may stay above 80 all night. Saturday is shaping up to be another hot day, but not quite as humid, with temperatures again in the 90s. Cooler and much drier weather settles in for Sunday.

Low temperatures may stay in the upper 70s to near 80 Saturday morning across the region. Around NYC, temperatures may not drop below the middle 80s. Image provided by WeatherBell.

Monday: Mostly sunny. High 80-87.

Monday night: Clear skies. Low 60-67.

Tuesday: Sunshine and some afternoon clouds. High 83-90.

Tuesday night: Partly cloudy, slight chance for a shower. Low 67-74.

Wednesday: Partly sunny, humid, chance for an afternoon or evening shower or thunderstorm. High 87-94.

Thursday: More clouds than sunshine, scattered showers and thunderstorms likely, some may produce heavy rainfall. High 80-87.

Friday: Lingering clouds early, then becoming mostly sunny, hot, and humid. High 90-97.

Saturday: Sunshine and a few clouds, a late-day shower or thunderstorm is possible. High 90-97.

Sunday: Mostly sunny. High 85-92.

Trouble Brewing in the Gulf

It’s been a fairly slow start to hurricane season in the Atlantic, which is fairly normal, but things are starting to heat up in the Gulf of Mexico.

A disturbance dropped southward from the Tennessee Valley over the weekend, moving into the Gulf of Mexico on Tuesday. With plenty of warm water and only a little wind shear, the system is starting to get organized this afternoon, and could become a tropical depression later today or on Thursday.

Thunderstorm activity is getting more organized in the northern Gulf of Mexico this afternoon. Loop provided by NOAA.

As of 2pm Wednesday, the system was centered about 155 miles east-southeast of the mouth of the Mississippi River, moving toward the west-southwest at 8 mph. It is producing sustained winds of 30 mph, with some higher gusts. Steady strengthening is expected for the next few days. A Tropical Storm Watch has been posted from the Mouth of the Mississippi River to Morgan City, Louisiana. A Storm Surge Watch has also been posted from Pearl River to Morgan City.

Forecast tracks for Potential Tropical Cyclone Two from various forecast models. Image provided by WeatherBell.

The forecast models are fairly unanimous that the system will continue westward for the next 36-48 hours, but after that point things become unclear. A turn toward the northwest and eventually north is expected as an upper-level trough moves into the Great Plains, but when that turn occurs has a very significant impact on the system. A quicker turn means that the storm spends less time over the warm waters of the Gulf, and thus has less time to strengthen. A later turn means the opposite, more time over water, more time to strengthen, and the greater likelihood of it becoming a hurricane. Intensity forecasts are notoriously poor to begin with, and this system is no different. Very few models are predicting the system to reach hurricane strength, but the National Hurricane Center’s official forecast does call for the system to become a hurricane before landfall. As we mentioned already, the eventual track of the system will play a large part in determining this.

Intensity forecasts from various models for Potential Tropical Cyclone Two. Image provided by the University of Wisconsin.

Storm surge is a danger with any storm system, and this one is no different. Storm surge of 2-4 feet is likely near where the center makes landfall. Since much of southern Louisiana is already low-lying, this could result in flooding for much of the region. Wind damage will also be a concern across the region, which again will be dependent on the strength of the system. Winds will pick up Friday night across portions of Louisiana and possibly eastern Texas, with landfall most likely on Saturday right now, but this is obviously subject to change.

Rainfall forecast for the Gulf Coast for the next 6 days. Image provided by Weathermodels.com

By far, the biggest threat with this system will be rainfall. Tropical systems produce copious amounts of rainfall, and this one will be no different. Rainfall totals of 6 to 12 inches are expected across parts of the Gulf Coast, with some amounts to 20 inches possible. This would produce widespread flooding across the region, but in this case, it will just exacerbate existing flooding problems. The Mississippi River remains above flood stage across the region, and this will only worsen the flooding. On top of that, thunderstorms dropped up to 10 inches of rain on parts of New Orleans Wednesday morning, and that’s before the precipitation from the system even reaches the area. The Mississippi River is expected to crest in New Orleans at a level of 20 feet, which is also the same height that the levee system protects the city to. Obviously this will bear watching. Upstream, the River has been above “Major Flood” stage in Baton Rouge since February 26. It’s not likely to drop below flood stage until at least some time in August, if then.

River forecast for the Mississippi River at New Orleans. Record flooding is not expected, but the levee system will likely be tested once again. Image provided by NOAA.

Elsewhere, the Atlantic remains quiet, with no other systems expected to develop in the next week or so.