flooding

November 17, 2023 Outlook: Last call for the tropical Atlantic and a sneak peek at Thanksgiving travel weather

One-sentence summary

Potential Tropical Cyclone 22 has a narrow window to develop before tomorrow when it slams shut in the Atlantic, and today’s post covers Wednesday travel weather which looks good with a couple big exceptions.

Potential Tropical Cyclone 22

We were expecting that Potential Tropical Cyclone 22 would become Vince later today as it races northeast across Jamaica, Cuba, and the Bahamas.

How to describe PTC 22? Quick and lower-end on the intensity scale. The main concern will be heavy rain as it races off northeast into the open Atlantic. (NOAA NHC)

But a look at satellite this morning suggests that 22 is still far from organized. The window for organization will remain open a bit longer before it slams shut, and 22 or Vince or whatever merges in with a non-tropical system in the open Atlantic, as it passes Bermuda.

PTC 22 lacks much organization whatsoever this morning, and it seems like getting to a true tropical storm will be an uphill battle. (Weathernerds.org)

So if PTC 22 were to become a tropical storm as it passes Jamaica, Cuba, and/or the Bahamas and Turks & Caicos Islands, how strong could it get? Not very. The ceiling on 22 is limited, probably to a minimal tropical storm. That said, it is going to bring a good deal of rainfall to the islands as it passes by, and as much as 8 additional inches could fall for portions of Jamaica or a bit more in southeast Cuba. As much as 4 to 8 inches or so will be possible in southern Haiti.

Rainfall from PTC 22 will be about 8 more inches in Jamaica, up to a foot or so in SE Cuba, and perhaps 8 inches or more in southern Haiti. (NOAA WPC)

So flooding is the primary concern with 22 as it trucks through the Caribbean and into the Atlantic today and tomorrow. With that, we suspect that the 2023 Atlantic hurricane season will come to an unofficial close.

Thanksgiving Wednesday travel outlook

With a lot of people hitting the road next week for the Thanksgiving holiday here in the U.S., we thought it might be helpful to give you an initial read on what travel conditions may look like for Wednesday.

The forecast map for Wednesday shows a stormy Northeast US and southeast Canada, a quiet central and western US, and some scattered storms in Florida. (NOAA WPC)

So, right off the bat, travel in the West looks fine right now. No issues are expected Wednesday. The Central U.S. looks quiet as well. A cold front will deliver scattered thunderstorms to Florida, this after some potential severe weather on Tuesday in the South. But overall, other than some minor issues, the expectation is that any travel to or from Florida will be fine.

The trouble spot on Wednesday looks to be the Northeast, Great Lakes, and Canada, where a potent storm will bring a bunch of issues for Wednesday. Chief among those issues will be wind, which is likely to cause delays at Northeast hubs like Boston, the NYC metro airports, and perhaps Philly and DC. Conditions should gradually improve later in the day Wednesday it appears, but there may be cascading delays due to airline issues there. I would also watch Chicago for potential issues with wind, which can always impact the air travel system. Aside from wind, some heavy snow is likely in parts of Quebec and interior Ontario, and some lake effect snow is likely in the snow belts of Michigan and perhaps off Lakes Erie & Ontario as well.

So if your travel plans take you north and east of about Indiana, you’ll likely want to have a little extra patience this year.

November 14, 2023 Outlook: South Florida flooding risks increase on Wednesday, while a separate Caribbean system makes a brief attempt to develop

One-sentence summary

Two separate systems are on the board, with one (non-tropical system) bringing heavy rain to Florida tomorrow and then heading off to the north, while another disturbance in the Caribbean has a chance to form before racing past Jamaica, Cuba, and Hispaniola later this week or weekend.

Florida flooding: Metro South Florida at risk for considerable flash flooding on Wednesday

Just a quick update this evening on what’s happening in the world of weather, and we’ll start in Florida. Areas just north of Miami have seen some heavy rainfall today, with two bullseyes of 4 inches or more, the first near Davie and the other around Pompano Beach, where over 5 inches has fallen.

Click to enlarge for impressive rain totals today north of Miami and west of Fort Lauderdale. (NOAA/RadarScope)

As showers diminish tonight, a quiet period will unfold before another, more widespread round of rain and storms tomorrow. This one will be capable of significant rain totals in excess of 4 to 6 inches to as much as 8 inches or even more tomorrow for parts of coastal, urban South Florida. Because of this, the NWS Weather Prediction Center has Miami-Dade, Broward, and portions of Palm Beach County under a moderate risk (level 3 of 4) for excessive rainfall and flooding risk on Wednesday.

A moderate risk (level 3 of 4) is posted for southeast Florida on Wednesday, as repeated rounds of heavy rainfall are possible, leading to more significant urban flooding. (NOAA)

Intriguingly (and somewhat confusingly), all of this may congeal into an area of low pressure off Florida’s east coast that has a low (albeit not zero) chance of developing into a tropical system as it races north and east. This is *not* the same system we’re watching in the Caribbean, but this one may produce a nor’easter type impact in eastern New England or Atlantic Canada by the weekend, including a chance of heavy snow on the back side of the storm for portions of Quebec, New Brunswick, or northern Maine.

Heavy snow is possible in portions of northern Maine and eastern Canada on the backside of this developing storm near Florida, as it comes north this weekend. (NOAA)

Tropical Update: Caribbean development remains possible later this week

Meanwhile, we continue to see at least the chance that a late season tropical system will form later this week in the Caribbean. The good news is that both the GFS and European model have tended to reduce the odds of anything significant developing.

Disorganized thunderstorms in the southwest Caribbean may develop into an organized system before it races north and northeast out to sea by the weekend. (Weathernerds.org)

So what was already a low chance of a significant storm is now quite low. Certainly heavy rain is possible, if not likely across the Caribbean, but getting this thing to depression status or even TS Vince, will take some effort. Can it get there? Sure, but I’m not sure it’s the most likely outcome. Regardless, interests in the central and western Caribbean should continue to monitor this thing until it passes.