Chances are decreasing that a tropical storm — which would be named Nadine — will form in the next few days.

There are two tropical disturbances that are worth keeping an eye on in the Atlantic, but in the last day, risks are dropping that either will be able to organize enough to become a named storm. It’s still possible that one or both could become tropical storms, but the deck is stacked against them.

Still, both systems could produce heavy rain and strong winds, and may affect land in the Caribbean region.

The first system, which the National Hurricane Center estimates has a 40 percent chance of eventual development, is expected to slip north of the Leeward Islands, moving toward the Turks and Caicos or the Dominican Republic this weekend.

The second system, a diffuse area of spin over the southwestern Caribbean, could meander north-northwest and bring squally weather to Nicaragua, Honduras, Guatemala and/or Belize. The Hurricane Center estimates this system has only a 20 percent chance of development.

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The struggling systems represent a stark change of pace from the past month and a half, which has featured a seemingly biweekly barrage of hurricanes battering the Lower 48. The Atlantic is running about 30 percent above average in terms of ACE, or accumulated cyclone energy — a metric that quantifies how much energy a season’s storms churn through. Philip Klotzbach, a researcher at Colorado State University, expects the next two weeks to feature near or slightly above-average hurricane activity. Even if the ongoing two systems struggle, Klotzbach said, the Caribbean may be an environment that could fuel development and strengthening should any additional storms form.

There will also be a broad region of rising motion, or upward-moving air, that will pass over the Atlantic in late October into early November. That could make it easier for storms to form — if the seedlings of any nascent disturbances are present.

The first system, now nearing the Lesser Antilles

On Wednesday morning, Invest 94L — the name given to the disturbance being monitored by the Hurricane Center — was located several hundred miles east of the Lesser Antilles in the central tropical Atlantic.

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While it exhibited plenty of spin and had a well-defined low-level circulation, it was struggling to sprout thunderstorms. That’s a requirement if it’s ever going to become a tropical storm.

Why is the system now struggling to develop into a named storm?

It’s struggling for two reasons. For starters, it’s being eroded by dry air. That’s what’s cutting back on convection, or shower and thunderstorm activity. Look at the dry air enveloping it:

Secondly, it’s being knocked off course by strong east-southeasterly winds. That’s blowing any thunderstorm activity downwind, or to the west-northwest, largely detaching it from the low-level swirl. Since the whole system is being actively knocked off-kilter, it can’t really organize.

Could this system still become a hurricane?

There might be a narrow window for development late Friday into Sunday as the system passes north-northwest of Puerto Rico. By then, it will be nearing the Turks and Caicos and perhaps the Dominican Republic.

Slightly warmer water temperatures, more readily available moisture at the mid-levels of the atmosphere and relaxed upper-level winds could fuel some organization. That’s if the system doesn’t get torn apart entirely before then.

There is at least a low chance that a tropical storm, or even low-end hurricane, could form over the weekend — but it’s working against the clock.

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By late Sunday or early Monday, a cold front will bring dry air and disruptive high-altitude winds to the region, ending any development chances and disrupting whatever system may be present there.

Still, Hispaniola, the Turks and Caicos, Puerto Rico and the southeastern Bahamas should continue to monitor the evolution of the system.

The second system, now in the Caribbean

A second system over the Caribbean also has lower-end development odds.

It’s currently a disorganized batch of showers and thunderstorms over the southwestern Caribbean. There is a low chance the spin associated with the disturbance could tighten and consolidate into a storm. However, that’s looking unlikely right now.